E7d e n t a l e p u b .

Volume3・2016

3rd molar Extraction Surgery

by EViDENT Academia, CIMIV

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E7d e n t a l e p u b .

EViDENT Academia is a group of young dentists that focus on lecturing ideas and innovation to others. In order for a better communication, we use digital works to explain the concepts. Most importantly we not only target the dentists as audience, but also the patients too. We are also proceeding the philosophy of evidence-based dentistry, especially in fields of periodontics, prosthodontics and dental implantology. The team was planned over a year (2014-2015) and collected data of needs from undergraduate dental students and dentists with clinical experience. We share our ideas, our studies, great articles, information of all kinds of dental courses for every dentists and students to get the latest news and discuss for our own protocols.

E7 dental e-publishing is one of the online/ paperwork of EViDENT Academia. The publication contains 7 topics per volume in different aspects of dentistry. It is more like a magazine with both dental research and the enjoyment of living. Including topics of lecturing, practical sessions, photos galleries, lifestyle sharing and etc. It is designed for dentists to have a brand new thinking in the academic field.

Authors could be from anywhere! E7 epub. is an open sharing work which everyone could subscribe and we are happy to have more and more dentists, professors, students and etc. to join us. We are more than welcome to hear your work experiences, knowledge and ideas, and encourage you to share with no limitation. Lastly, we welcome any kind of suggestions which will help us improve.

EViDENT Academia

About

From Chairman Our team EViDENT Academia is based on information sharing. We believe that by sharing, we are not giving away, but instead, we are gaining knowledge. It is a pleasure to finally release our third volume and many thanks to our readers. We are currently planning some activities for young under-graduated dentists and hope to help them in future practice. Now we hope to extend our literature and connect it with hand-on practical work to expand and allow easier learning and comprehension for our readers.

Chairman

From Editors 2016 is a special year for our team. Lately we changed our name to EViDENT Academia. We organized our different brands into a simple, and very classic form to present to all our friends. As before, we focused on evidenced-based of techniques to share and support these kind of research. In the other hand, you could read our articles with the latest digital methods in Dentistry. It is like drive a sport car but with a very concrete and safe mind.

One of our course is coming during this Summer. “1 Day Prosthodontic Implant Course Undergraduate Students” with Dr. Fernando and his team MPI. (Mediterranean Prosthodontic Institute) We are excited to present our work and elevate our skills in both academic and clinical way. To me, all these works are precious and ready to share!

Editor-in-Chief

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Contents

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Calendar

Contact Email: evident.academia@gmail.com Issuu: https://issuu.com/perio.prostho.cc Facebook: EViDENT Academia Associated Blog: https://perioprosthocc.wordpress.com

E7 Dental E-publishing Volume 3, May, 2016

Publisher/ Editor-in-Chief: Chen-Che Hung Senior Editor: Wei-Hua Chen

EViDENT Academia Dental Education

Chairman: Ya-Hui Chuang Secretary-General: Chen-Che Hung

Copyright © 2016 EViDENT Academia Dental Education.

Articles may be quoted and referenced with the description from the reference data. Permission requests that exceed the above guidelines and instructions must be directed to and approved in writing by EViDENT Academia Dental Education.

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EViDENT Academia

1 … About

3 … Calendar & Contents (dental events)

4 … Caries Treatment between Conventional and Minimally Invasive Approaches

7 … The Use of Semi-precision Attachments in Removable

Prosthodontics Part 2: Treatment Planning & Attachment

Selection and etc.

18 … Periodontal Risk Assessment (PRA) in Clinical Case: Reviews and Results

22 … Introduction to Orthodontic Dental Classification

26 … Brief Introduction of Oral Cancer and Related Oral

Tumours

31 … Dental Presentation & Techniques using Apple Keynote Part 1: Mask Techniques & Background Design

33 … Risk Factors of Osteonecrosis Considered before Implant

Placement for Patient Receiving Antiresorptive Therapy

Part 1: Clinical Use & Risk Factors of ARONJ

Introduction

Caries is commonly thought of as the result of “bacteria eating” teeth. Instead, it is a consequence of bacteria fermentation. This occurs when one consumes carbohydrates and sugar, the bacteria in the mouth fermentates the food and releases acid as a by product.1 The release of acid leads to a drop in pH of the mouth, and as a consequence of that, enamel demineralisation.1 The time food remains in the mouth and the frequency of food consumption are factors that affect on caries formation.1 When theses factors can be well controlled, it is possible to control and prevent caries formation. However, caries is complex, host factors and food properties also contribute, such as teeth quality and food consistency.1 Therefore when caries is formed, it is important to treat it early to prevent further advancement of the caries into a prosthetic crown, or even an unfortunate extraction.

The treatment of caries can be separated into two main approaches, conventional and minimally invasive (MID). The conventional approach is the traditional method based on Greene Vardiman Black’s work on operative dentistry. This involves the complete removal of infected caries followed by composite restoration.2 In the case of amalgam restorations, further extension to all the fissures to prevent future decay is necessary.2

On the other hand, the minimally invasive method does not involve removal of sound enamel, it is based on conservation of tooth structure.3 There are also many differences in terms of material and instruments used.

Discussion

The conventional and minimally invasive approaches in caries treatment differ greatly in terms of caries excavation, material and instrument choice. Regarding to the different severity of caries, treatment options also differ between conventional and minimally invasive. These differences will be compared in the following discussion.

Caries Excavation

The conventional approach removes all infected caries, leaving a hard surface for restoration.2 Unlike the conventional, the goal in MID is to remove as minimally required as possible, in order to not weaken the tooth structure.2 A layer of soft infected dentine can be left when the pulp is very close, to not expose the pulp and intend to promote remineralisation.4 The process of caries excavation has more options in terms of instrument choice in MID. In the conventional approach, only rotary instruments (high-speed turbine and low-speed contra-angle) with dental burs (of tungsten carbide or diamond material) are used. In MID, many methods have been developed for caries excavation, which can be classified as mechanical and non-mechanical, rotary and non-rotary.5 Methods include the use of dental burs (of ceramic or polymeric material), manual excavators, air-abrasion, air-polishing, ultrasonication, sono-abrasion, chemo-mechanical methods, lasers and enzymes.6 Mechanical refers to using instruments that mechanically remove caries, such as using dental burs and excavators. Non-mechanical is the use of chemicals such as the system Carisolv.7 (Figure 1) Hand instruments are commonly used as a more conservative way to

Caries Treatment between Conventional and Minimally Invasive Approaches

Ya-Hui Chuang

keywords: ART, caries, minimal invasive, operative dentistry, treatment planning

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commonly used as a more conservative way to remove decay and allow the operator to feel the consistency of the decay and not to over excavate, which is common with tungsten carbide and diamond burs. The technique is called atraumatic restorative treatment (ART). As the name implicates, the process is “atraumatic”, causes less pain due to the slow and gentle movements. This allows patients to have less anxiety towards dental treatment and decreases operator stress.

Initial Caries

These caries are white spots and caries that are limited in the enamel. In conventional dentistry, enamel caries are treated by removal and restoration. In MID, no tooth structure is removed. These caries are treated by prevention of further lesion progression. Actions include patient education on caries prevention and diet recommendation, fluoride application, and resin infiltration. Resin infiltration is an effective and conservative method in treating white spots, fluorosis spots and non-cavitated caries. Resin infiltration fills in the pores and blocks acid from penetrating, thereby arrests lesion progression.8

Moderate Caries

These caries have passed the dentinoenamel junction, but remains within half of the distance to the pulp. Treatment differs mainly by the use of instruments and material use. For moderate caries treatment with conventional method is similar to initial caries, removal of caries buy rotary burs and then restoration by composite. Whereas in MID, the ART can be a choice for patients with anxiety to dental treatments and patients with difficulty to maintain position in

Fig 1 Commercial package of caries debridement Carisolv Multimix gel.

Initial Caries Moderate Caries Advanced Caries

Fig 2 Comparison between different stages of Caries

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the dental chair (such as children and patients with disability). The previous mentioned excavation methods, air-abrasion, air-polishing, ultrasonication, sono-abrasion, chemo-mechanical methods, lasers and enzymes, can also be applied.6 In MID resin-modified glass ionomer cements (GIC) can be used for fluoride releasing effects and still have the mechanical properties to withstand functional use in the mouth. Studies have shown that treatment with GIC shows the same results as restorations with composite, the survival rates are similar.9,10

Advanced Caries

These caries have extended pass half of the distance to the pulp. In cases where the caries is very close to the pulp, the conventional approach of using rotary instruments would be extremely hard to not accidentally expose the pulp, which would straight lead to a root canal treatment (RCT) in adults or direct pulp capping in younger patients. In MID, a RCT is the least wanted, therefore every treatment is intended to prevent the requirement of a RCT. In these ca r ies , the ART wou ld be recommended to slowly excavate the soft dentin and leave a thin layer of soft infected dentin to not expose the pulp and act as a protective layer which can be remineralised with GIC. This technique is called the sandwich technique where a layer of GIC is put then the cavity is restored with composite. Studies have shown good resul ts of restorations with ART.10,11 (Figure 2)

Conclusion

As knowledge is growing, technology improves greatly, so has dentistry. The treatment method of caries has evolved into several approaches. Minimally invasive dentistry has become much more common as more dentists are carrying out minimally invasive treatments in practice. Caries treatment is not merely just removal of decay and obturation with composite anymore, dentists now have many more ways to treat caries depending on the severeness.

Reference

1. Hicks J, Garcia-Godoy F, Flaitz C. Biological factors in dental caries enamel structure and the caries process in the dynamic process of demineralization and reminera l i za t ion (par t 2 ) . I JCPD. 2005;28(2):119-124.

2. Black GV, Blackwell R. G.V. Black's work on operative dentistry with which his special dental pathology is combined ... Present revision by Robert E. Blackwell ... Eighth edition. Medico-Dental Pub. Co.: Woodstock, Ill.; 1948.

3. Hamama H, Yiu C, Burrow M. Caries management: a journey between Black’s principals and minimally invasive concepts. IJDOS. 2015;:120-125.

4. Banerjee A. Minimal intervention dentistry: part 7. minimally invasive operative caries management: rationale and techniques. BDJ. 2013;214(3):107-111.

5. Banerjee A, Watson T, Banerjee D. Dentine caries excavation: a review of current clinical techniques. BDJ. 2000;188(09):476-482.

6. Banerjee A, Watson T, Banerjee D. Dentine caries excavation: a review of current clinical techniques. BDJ. 2000;188(09):476-482.

7. Maru V, Shakuntala B, Nagarathna C. Caries removal by chemomechanical (CarisolvTM) vs. rotary drill: a systematic review. Open Dent J. 2015;9(1):462-472.

8. Meyer-Lueckel HParis S. Improved resin infiltration of natural caries lesions. J. Dent. Res. 2008;87(12):1112-1116.

9. Lo E, Luo Y, Tan H, Dyson J, Corbet E. ART and Conventional Root Restorations in Elders after 12 Months. Journal of Dental Research. 2006;85(10):929-932.

10. Molina G, Faulks D, Mazzola I, Mulder J, Frencken J. One year survival of ART and conventional restorations in patients with disability. BMC Oral Health. 2014;14(1):49.

11. Frencken J, Leal S, Navarro M. Twenty-five-year atraumatic restorative treatment (ART) approach: a comprehensive overview. Clin Oral Invest. 2012;16(5):1337-1346.

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TREATMENT PLANNING

Prosthodontic Principles Although there are few scientific data to aid in attachment selection, there are some prosthodontic principles that should be used. Like other direct retainers, attachments must also provide: 2

1. Support – to resist movement of the RPD toward the tissue.

2. Retention – to resist movement of the RPD away from the tissue.

3. Reciprocat ion – to neutral ize and counteract the torqueing forces exerted by the retentive element.

4. Stabil ization – to resist horizontal movement of the RPD.

5. Fixation – to resist movement of the tooth away from the RPD and the RPD away from the tooth.

6. Passivity – to remain passive when the RPD is in its terminal position, if not, orthodontic effect would present.

Forces should be widely distributed to all available tissues, no matter which kind of retainer used. The denture base of tooth/tissue-supported removable partial dentures should be extended to the entire residual ridge within the limitation of functional muscle movements. The teeth and denture supporting area should both be used to provide support, bracing, direct and indirect retention, and stability. If one of these tissues is incapable of providing these functions, other restorations

should be considered.9 If an attachment doesn’t meet one or more of the requirements above, there might be a failure in the prosthetic treatment.

It is important that the removable partial denture framework can be properly related to the teeth and the denture base to the framework. This principle is satisfied if the entire framework is rigid and the framework contacts three or more teeth, preferably widely separated and with rest seat preparations. If there are only two abutment teeth in contact with the framework without any other way to relate the framework to the teeth, the denture wouldn’t be stable during functioning. If a resilient attachment is used, there must be an additional contact between the framework and the attachment teeth.9

Abutment Teeth for Attachments

Abutment selection

The anatomy of the abutment tooth and the space requirements for the attachment must be considered. The interocclusal space, crown height, and crown-root ratio are also important factors to be considered when making the treatment plan.13 Adequate space between the pulp and the normal contours of the tooth is necessary for the female component of an intracoronal attachment. If the pulp of the abutment tooth is large, preparation of the tooth for a crown plus additional reduction for placement of an internal attachment may

The Use of Semi-precision Attachments in Removable Prosthodontics

Part 2: Treatment Planning & Attachment Selection and etc.Hing-Ger Lau, DDS.

keywords: precision attachment, semi-precision attachment, prosthesis, prosthodontics

*the article is modified to adjust for the template.

*original copy could be found in Dentistry Degree Project of Universidad CEU Cardenal Herrera.

*for Part 1, please refer to Lau HG, The Use of Semi-precision Attachments in Removable Prosthodontics Part 1: Classification & Survival Rate, E7

dent., 2015;2:15-20

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necessitate root canal therapy. This may not preclude the use of attachments, but may be an indication for the use of an extracoronal attachment. The three dimensional size of the t oo th w i l l p red i c t t he f unc t i ona l o r biomechanical success with this attachment. For using an intracoronal attachment, vertical space of at least 4 mm and buccolingual space of 3 mm is usually required.(Figure 1, 2) 7

Unlike intracoronal attachments, extracoronal attachments need no space within the abutment crown and are unrestricted by pulpal considerations requiring less reduction of the abutment tooth. They may be employed where buccolingual space is limited. They are particularly useful where lower canines are the most distal abutments.7 However, extracoronal attachments usually require larger attachment height than intracoronal attachments do. The reason is explained in detail in the following figure 3.

Abutment Preparation

The taper of the prepared abutment is a critical factor affecting the retention of the crown. According to a research done by Anselm H.W. et al., the relationship between abutment taper and resistance to dynamic lateral loading is approximately linear.14 It means that the greater the taper, the worse the retention of the crown would be.

Teeth Splinting or Double Abutting

Studies demonstrated that the splinting abutment teeth resulted in a significant decrease in the mesiodistal and buccolingual movements of the distal abutment under vertically applied loads.9,15

An abutment tooth is subjected to additional loads, part icularly when supporting a cantilevered fixed prosthesis or a distal-extension removable prosthesis. Two or more adjacent teeth are recommended to be splinted together. When two teeth are connected there is an immediate increase in support of occlusally directed forces within 15~25%. Connecting more than two teeth increases the support against laterally inclined forces but appears to have little extra effect when occlusal directed loads are applied.16 Aydinlik et al.17 has found that a significant decrease in the magnitude of abutment tooth movement, from 6% on the loaded side and 78% on the unloaded side, can be obtained by splinting.17

Fig 1 (a) A premolar with adequate buccolingual width. (b) An incisor with insufficient buccolingual width for an intracoronal attachment.

Fig 2 (a) Maximum attachment length 6mm. (b) Minimum attachment length 4mm. (c) Inadequate attachment length < 4mm.

Fig 3 Gingival clearance (a) of about 2mm is advisable to be left between the bottom of the attachment and the residual ridge to promote the oral hygiene control and periodontal health of the area.13 (b) A space should be left occlusally as well for the porcelain to cover the attachment which improves the esthetics.

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An in vitro experiment done by Altay et al.15 has concluded that splinting doesn’t affect the direction of abutment tooth movement. They ’ ve a l so con f i rmed P i c ton and Manderson’s statement that there is a significant decrease in mesiodistal and buccolingual movements of the splinted abutment teeth but no change in the magnitude of the vertical movement. And there is also a signif icant decrease of the mesiodistal and buccolingual movements of splinted abutment teeth when the partial denture was bilaterally loaded compared to unilaterally loaded.15

Attachment Selection

Proper attachment selection requires evaluation of 3 factors: location, retention, and available space.

Location

Location is one of the most important factors that affect the selection between using a rigid or resilient attachment. In bounded saddle area, r igid precision attachments are favorable. And in distal extension saddle area, resilient semi-precision attachments that allow certain amount of movement are usually used.3,4,5,7,8,9

Retention

There are several ways to impart retention to the design. The first way is by the use of frictional force between nylon sleeve and male component of the RPD. An exchangeable nylon sleeve can be incorporated into the inner part of the female component to provide retention.(Figure 4) The use of nylon sleeves provides not only retention but also resiliency for the RPD. Greater surface contact will usually correlate with an increase in the amount of retention.3 The second way is by confining the paths of withdrawal to only one path. By the use of systems like key and keyway, we can have only one vertical path of withdrawal and therefore prevents the prosthesis from falling off from directions other than the path of withdrawal. (Figure 5) The last

way is by using mechanical retention using a lingual bracing arm. The tip of the lingual bracing arm engages to the undercut of the abutment tooth and acts as a retentive clasp and the lingual wall of the semiprecision attachment provides reciprocation. Sometimes if the lingual bracing arm is not engaging into any undercut of the abutment crown, the retention is going to be imparted by the nylon sleeve, and the bracing arm provides support and stability.

Space

Space is a principal consideration for the selection of an attachment. Vertical space is measured from free gingival margin to the marginal ridge of the abutment. Cautious placement of the superior aspect of the a t tachment w i l l c i r cumvent occ lusa l

Fig 4 Nylon sleeve incorporated in the female component of an extracoronal attachment to provide resiliency and retention. Note that the lingual bracing arm in here can provide stability and support.

Fig 5 Dislodging movements other than the path of withdrawal are resisted by the buccal and lingual (palatal) wall of the attachment.

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interferences. The length of attachments that rely on fr ict ional retention should be maximized to maintain maximum retention and resistance to dislodgment. Placement of the attachment should be as low on the tooth as possible to reduce the tipping or leverage forces applied. Buccolingual space is equally important to avoid over-contouring the crown. Additional bulk will be required buccal and lingual to the attachment for the casting alloy. Proper analysis of mesiodistal measurement ensures proper proximal contour and will provide an indication of a need for boxes in the development of the preparation. The largest attachment possible should be selected. This requires careful preparation analysis that includes the arrangement of denture teeth in a diagnostic wax-up. This will help ensure the highest functional and esthetic value to the reconstruction.3

Rotation Control

Rotation Around the Horizontal Axis

Rotation around the horizontal axis can be achieved by using two different metals, one softer than the other, in the construction of the male and female components, allowing one component to wear or even selectively machine of the components to allow some degree of reciprocal movement. The other way to achieve this is by rounding the occlusal outline of the attachment as well as any of the angles on the male component or occasionally the internal angles of the female component.

Rotation around the Longitudinal Axis

Parallel-sided walls allow no rotation around the longitudinal axis. And if an attachment is to be used in distal extension area or in abutment teeth with reduced periodontal support, some degree of longitudinal rotation must be allowed in order to release stress on the abutment tooth. Modifying the taper of lateral walls increases the distal extension saddle’s ability to rotate about the longitudinal axis. The greater is the taper, the more rotation around the longitudinal axis will be. The tapered form also permits easier insertion of the RPD and is

especially important where patients have problems of reduced manual dexterity. (Figure 6)

Attachment Selection according to Kennedy Classification

Clinical success using attachments requires an awareness of the potential forces a prosthesis can transfer to the teeth and residual ridges, as well as the methods available to reduce or distribute these forces. Analysis begins by classifying the edentulous spaces using Kennedy Classification System.

Kennedy Class III Partially Edentulous Arch

For a totally tooth-supported prosthesis restoring a posterior edentulous space, there is no tissueward movement of the denture and therefore no stabilizing fulcrum line. In such a situation there is little controversy that the best treatment would be a rigid intracoronal attachment. This attachment provides not only good retention, but also excellent support and stability because of its rigid interlocking components. However, if the long-term prognosis for one or both of the posterior abutment teeth is questionable, then a stress-breaking type of extracoronal attachment can be used with the anterior abutments in contingency planning for the future loss of these teeth because after losing the posterior abutments, the case would convert into a Kennedy class II with distal extension saddle,

Fig 6 Tapered walls prepared for semi-precision attachments.

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which a stress-breaking type of attachment would be favorable.9

Kennedy Class IV or class I and II with Anterior Modification Partially Edentulous Arch

These clinical situations are best treated with a fixed partial denture in the anterior edentulous space whenever possible.9 However, on occasion, attachment type removable partial denture designs should be considered. This is particularly true when the edentulous ridge has an uncorrectable bony d e f e c t c o m p r o m i s i n g e s t h e t i c s a n d contraindicates the use of a fixed partial denture. The removable partial denture will incorporate a tissue-colored base that will substitute for the missing tissues and provide acceptable esthetic results. The ideal removable partial denture design for such situations involves the use of a tissue bar placed close to the edentulous ridge and connected as a fixed unit to the abutment teeth on either side of the space, using crowns or resin retainers.9 Retention is provided by using a retentive clip or stud that is incorporated into the denture base and either snaps over or into the bar. However, if a rather smaller anterior edentulous area exists, it may be restored with a bounded sadd le re ta ined by r ig id intracoronal attachments.7

Kennedy Class I and II Partially Edentulous Arch

The most difficult type of treatment plan is the one involving the distal extension removable partial denture, which relies on support from both hard and soft tissues. The distal extension removable partial denture must be considered differently and in more detail than the totally tooth-supported situation when selecting attachments. Such a situation is controversial and there are a number of treatment philosophies. Depending on whether abutment teeth are periodontally involved and the bony quality of the residual ridge, different treatment philosophy should be planned.

Stress-breaker Philosophy

Some practitioners believe that the distal extension removable partial denture should use a resilient or stress-breaking attachment. The theory is that some vassal movement is inevitable during the function of a distal extension base that rests on soft tissue.3,4,5,7,8,9 Advocates of the stress-breaker philosophy believe that the loading of the distal extension will result in rotation and torqueing of the abutment tooth when the components of an attachment are rigidly connected. This may result in damage to the periodontium and unwanted orthodontic effect.9 Opponents believe that stress-breaker attachments allow the application of excessive force to the residual ridge, causing premature resorption of the denture-bearing area. Also, stress-breaker attachments are thought to be mechanically more complex than rigid attachments and may be subject to increased wear and breakage.9

Rigid Attachment Philosophy

Another concept advocates the use of the rigid attachment in constructing the distal extension removable part ia l denture. Advocates indicate that the edentulous ridge, with a precisely fitting denture base, can provide as much support as the abutment teeth. A removable partial denture with a cast metal base developed from a mucostatic impression technique is desired. However, opponents believe that the edentulous ridge cannot provide as much support for the prosthesis as the abutment teeth, stating that when tissueward loading of the prosthesis occurs, forces are transferred to the rigid attachment and abutment teeth. This applies potentially damaging torqueing forces to the abutment teeth.3,4,5,7,8,9

Floating Denture Base Concept

Another philosophy is known as the stable base precision attachment removable partial denture concept or the floating denture base concept. This concept incorporates rigid intracoronal attachments and a cast metal base made from a mucostatic impression of the residual ridge. The male portion of the attachment is connected to the denture base,

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allowing complete seating within the abutment tooth component only when the prosthesis is loaded with tissueward force. Therefore, at rest, the tissues of the denture-bearing area are in their anatomic form and the attachment is not completely seated. (Figure 7a) The denture at this stage is totally tissue supported. In function, the tissues of the denture-bearing area are displaced into their functional form and the vertical stops of the attachment contact, allowing the attachment to resist further occlusal forces. (Figure 7b) Only at this stage is the denture supported by the teeth as well as the edentulous ridge. There is an impression technique which can be applied here called altered cast technique.

With the use of altered cast, we can have a cast model with both the anatomic form of the teeth and the functional form of the residual ridge. The technique involves making the impression with materials like polysulfide first to record the anatomy of the teeth and an additional impression of the distal extension area with mucocompressive materials like impression compound. After having the first impression, the distal extension part of the model is cut. And after the second impression is taken, it’s poured together with the first model.

Proponents of this concept claim that the stimulation of the tissues under such a denture base prevents or retards residual ridge resorption. Opponents suggest that the rigid intracoronal attachment allows only vertical movement of the denture base. This does not adequately allow for any rotational movement of the base that might otherwise occur in function. Therefore, the attachment may bind, producing adverse forces on the abutment teeth.9

Force Distribution

An important factor to consider in selecting a philosophy for treating patients requiring distal extension removable partial dentures with attachments is balance between the forces

Fig 7 Floating denture base concept: (a) At rest, the tissues of the denture-bearing area are in their anatomic form and the attachment is not completely seated. (b) In function, the tissues of the attachment come into contact, allowing the attachment to resist further occlusal forces.9

(a) (b)

Healthy Periodontium Unhealthy Periodontium

Well-rounded Dense Bone Tooth and Tissue Borne Mainly Tissue Borne

Knife-edged Bone Mainly Tooth Borne Tooth and Tissue Borne / Contraindicated

Residual Ridge Quality

Abutment Teeth Periodontal Status

Tab 1 Depending on the quality of the periodontium around the abutment teeth and the quality of the residual ridge which the denture base is going to be seated on, treatment philosophy of whether using teeth supported or mucosa supported RPD system can be decided. Be aware that caution must be taken when using mainly teeth to support the denture, excessive force constantly transmitted from the saddle area could still end up damaging the abutments.3 If the periodontal status is unfavorable with a knife-edged poor-quality bone we should think of treatment options other than attachment retained dentures.

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applied to the residual ridge and abutment teeth.9 Philosophies vary greatly regarding the amount of support provided to the prosthesis by the individual structures. (Table 1)

Other factors also influence attachment s e l e c t i o n . T h e s e i n c l u d e i n t e r a r c h relationships, existing and proposed occlusal design, interocclusal space, space available for attachment selection, treatment prognosis, and prosthesis design.7,9,13

Other Application of Attachments

Intracoronal attachments can be used as a connector in long span bridgework or in situation where multiple paths of insertion exist. Larger-span bonded gold and porcelain

restorations may be split into sections. Connecting each section with an intracoronal a t tachment min imizes the e ffec ts o f dimensional changes of the metal that may accompany porcelain firing. Devitalization of tilted abutments may be avoided by the use the an attachment to connect the tilted abutment with the rest of the abutment teeth.7

(Figure 8)

Conclusion

Removable partial dentures fabricated with precision attachments are the viable options for patients in whom fixed prosthesis and implants are contraindicated. Adherence to precision techniques, proper diagnosis and periodic recall preventive therapy will result in

Tab 2 A guideline to follow when making treatment plan of partially edentulous cases using attachments as direct retainers.9

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successful treatment and preservation of the patient’s existing dentition. It’s very important that proper type of attachment is used and correct treatment for different cases must be planned. Every patient must be treated individually. Patient’s Kennedy’s class, periodontal status, bony quality of residual ridges must be studied carefully in order to select the most proper treatment philosophy for every single patient.

From a personal point of view, double abutments should be used whenever possible in order to improve the longevity of the abutment teeth and the survival rate of the a t t a c h m e n t - r e t a i n e d r e m o v a b l e prosthodontics. In Kennedy class III cases, generally rigid attachments on both sides of the saddle should be used. In some cases which posterior abutments have poor prognosis due to maybe unhealthy periodontal condition, we would consider using a resilient attachment on the anterior abutments to avoid having a rigid attachment connecting a distal extension saddle in the future after losing the posterior abutments. In Kennedy class IV cases, to restore anterior bounded saddle

area, patients are best treated with either fixed prosthodontics or rigid attachments depending on whether an anterior bony defect exists which affects esthetics or not and the support of the prosthesis should be provided by the abutment teeth.

In Kennedy class I and II cases, there are more proposals of different treatment options with semi-precision attachment. In my opinion, a resilient extracoronal attachment should be used whenever possible. I personally don’t agree with the rigid attachment philosophy. If a rigid must be used, floating denture base concept is a good option to be considered. However, some opponents say that rigid attachments can only tolerate vertical movement and as a retainer for distal extension saddle, some rotation about the longitudinal and horizontal axis must be tolerated as well. This problem could be overcome by using different types of metal for casting the male and female component and rounding the angles of the male component. Tapering of the lateral wall can increase the ability for the distal extension to rotate about the longitudinal axis.

Fig.12 (a) As demonstrated above, a mesially tilted lower third molar has been chosen as an abutment tooth for retaining a 5-unit bridge from lower first premolar to lower third molar. If no orthodontic treatment is planned in this case to bring the third molar upright, in order for the 3 abutments to obtain a uniform path of insertion for the bridge, a very aggressive preparation and thus an endodontic treatment on the lower third molar must be done. Moreover, the shape of the prepared crown wouldn’t be ideal for receiving a crown or bridge and therefore the prognosis of this treatment plan would be doubtful. (b) By the use of an attachment, devitalization of the tilted abutment tooth is avoided. The 5-unit bridge is divided into 2 parts, one is a metal ceramic crown retained by the tilted molar, and the other would be a distal extended cantilever bridge retained by the 2 premolars. An intracoronal attachment is incorporated within a metal-ceramic crown placed on to the tilted third molar and the male component of the attachment is incorporated onto the distal wall of the cantilever bridge’s pontic. In this way, the tilted third molar could be used to retain the bridge without any aggressive preparation or devitalization.

(a) (b)

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Precision and semi-precision attachments are very good opt ions to consider when conventional clasps are not available due to esthetic or other reasons. However, during the researching process of this project, I’ve found out that there are much less recent research articles published than the ones before year 2000. This may reflect the fact that the treatment with semi-precision attachment are less popular over the past few years. People nowadays often pass over this option and think of dental implants directly. The use of attachment should never be neglected since it’s still a valid treatment option with acceptable price and long-term prognosis. It can be considered when implants have been rejected as a treatment option.

Acknowledgment

Articles reviews and clinical photos were provided by Dr. Alastair Edwin Dent, DDS, MS, Department of Prosthodontics CEU Cadernal Herrera.

Reference

1. James S. Brudivik. Advanced Removable Partial Dentures. Quintessence Publishing Co, Inc

2. Robert P. Semiprecision attachment-retained removable partial dentures. QDT 1994:137-144

3. Sumit Makkar, Anuj Chhabra, Amit Khare. Attachment Retained Removable Partial Denture: A Case Report. Int. Journal of Clinical Dental Science

4. Z. Ben-Ur, I. Aviv, C. Gorfil, R. Himmel. The semiprecision connector design for distal extension removable partial dentures. Quintessence International Volume 19, Number 12/1988

5. D.R. Burns, J.E. Ward. “Review of attachments for removable partial denture design: 1. Classification and selection,” T h e I n t e r n a t i o n a l J o u r n a l o f Prosthodontics, vol. 3, no.1, pp. 98-102, 1990.

6. Mu YD, Fan YB, Yang XM. Clinical study on the abutment periodontal condition with extracoronal attachment denture. Hua Xi

Kou Qiang Yi Xue Za Zhi. 2008 Aug;26(4):371-3

7. H W Preiskel. Precision attachments for partially dentate mouth. Annals of the Royal College of Surgeons of England (1974) vol 55

8. Naveen Gupta, Abhilasha Bhasin, Parul Gupta, and Pankaj Malhotra. Case Report: Combined Prosthesis with Extracoronal Castable Precision Attachments. Hindawi Publishing Corporation, Case Reports in Dentistry Volume 2013, Article ID 282617, 4 p a g e s h t t p : / / d x . d o i . o r g /10.1155/2013/282617

9. D.R. Burns, J.E. Ward. “A review of attachments for removable partial denture design: part 2. Treatment planning and attachment selection,” The international Journal of Prosthodontics, vol. 3, no.2, pp. 169-174, 1990

10. Johannes S, Manfred W, Stephan R, Jorg H, Stefan H. Five-year clinical follow-up of prefabricated precision attachments: A comparison of uni- and bilateral removable dental prostheses. Quintessence Int 2011;42:413-418

11. Zajc D, Wichmann M, Reich S, Eitner S. A prefabricated pacision attachment: 3 years of experience with the Swiss Mini-SG system. A prospective clinical study. Int J Prosthodont 2007;20:432-434

12. Studer SP, Mader C, Stahel W, Scharer P. A retrospective study of combined fixed-removable reconstructions with their analysis of failures. J Oral Rehabil 1998;25:513-526

13. Peraire M, Rustullet O, Anglada JM, Salsench J, Gil JA. Limitation in the use of a t t a c h m e n t s i n a M e d i t e r r a n e a n population. Quintessence Int. 1996 Jul;20(7):469-71

14. H.W. Anselm Winkott, Jack I. Nicholls, Urs C. Belser. The relationship between taper and resistance of cemented crowns to dynamic loading. Int J Prosthodont 1996;9:117-130

15. O.T Altay, P. Tsolka, H.W. Preiskel. Abutment Teeth With Extracoronal Attachments: The Effects of Splinting on Tooth Movement. The International Journal of Prosthodontics, 1990;3:441-448

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16. Picton DCA, Manderson RD. On the biomechanics of complete and partial dentures, in Bates JF, Neill DJ, Preiskel HW (eds): Restoration of the Partially Dentate Mouth. Proceedings of the International Prosthodontic Symposium. Chicago, Quintessence Publ Co. 1984, pp 27-41

17. Aydinlik E, Dayangac B, Celik E. Effect of splinting on abutment tooth movement, J Prosthet Dent 1983;49:477-480

18. Rifat GOZNELI, Coskun YILDIZ, Burcin VANLIOGLU, Buket Akalin EVREN and Yasemin KULAK-OZKAN. Retention behaviors of different attachment systems: Precious versus non- precious, precision versus semi-precision. Dental Materials Journal 2013; 32(5): 801–807

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Carl Milles, Guds Hand, Bronze, 1949-1953 Millesgården, Stockholm

Because you are my help, I sing in the shadow of

your wings. I cling to you; your right hand upholds

me. (Psalm 63:7-8)

Christian Love Art ProjectClassic Art with Passages from Bible

public domain

Introduction

Periodontitis could have been considered as the most common dental disease to find in the daily clinical visit. Mild forms of periodontal disease affect 75 percent of adults in the United States, and more severe forms affect 20 to 30 percent of adults.1

Not only the scaling and root planning treatment (Sc/Rp) should be provided but also the management of the supportive therapy to control the efficient of the outcomes and possibilities of the recurrence.

Periodontal Risk Assessment (PRA) established by Lang N. and Tonetti M. provides a functional diagram (Figure 1) for the practitioners to classify their patients into different groups and records the data to have a better method monitoring their patients.2 The patient’s risk assessment for recurrence of periodontitis may be evaluated on the basis of a number of clinical conditions whereby no single parameter displays a more paramount role. The entire spectrum of risk factors and risk indicators ought to be evaluated simultaneously.2

The frame is designed into 6 different characteristics.

1. Percentage of bleeding on probing 2. Prevalence of residual pockets greater

than 4 mm (5 mm) 3. Loss of teeth from a total of 28 teeth 4. Loss of periodontal support in relation to

the patient’s age 5. Systemic and genetic conditions, and

6. Environmental factors, such as cigarette smoking.

Each parameter has its own scale for minor, m o d e r a t e a n d h i g h - r i s k p r o f i l e s . A comprehensive evaluation of the functional diagram will provide an individualized total risk profile and determine the frequency and complexity of SPT visits. Modifications may be made to the functional diagram if additional factors become important according to new evidence.2

Although significant researches have shown the importance of preventing the causes of periodontitis, attention of the diseases is still low due to the oral hygiene education to the patients. Dentists and specialists should support and encourage the patients for taking care their teeth.

Periodontal Risk Assessment (PRA)

in Clinical Case: Reviews and ResultsChen-Che Hung, DDS.

keywords: case study, periodontics, periodontitis, risk assessment, Sc/Rp, supportive treatment

*the article is also available on perio.prostho.cc.wordpress.com

Fig 1 Periodontal Risk Assessment (PRA) functional diagram designed by Lang N.P., Tonetti M.S.²

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Case Report

47 years old female patient came to the dental clinic of Universidad CEU Cardenal Herrera seeking for a periodontal treatment due to her teeth mobility at posterior region. (#30, #31) She explained her anxiety and hoped the dental treatment is secured. The diagnosis included intra-oral check-up (Figure 2) and radiographic examination, including panoramic and periapical series. (Figure 3)

BOP is significant at 3 quadrant of the oral cavity. The entire oral cavity was lack of plaque control, which is an issue for the periodontitis.3 Pocket depth (PD) is serious due to the lost of alveolar bone. Treatment of periodontal disease is essential to establish.

Clinical records is presented as the following using online periodontal chart and PRA from Perio-Tools.com.

Standard Sc/Rp procedures was proceeded. The patient was advised to use mouth rinse (Perio·Aid®) after toothbrushing at home. and revaluation was approached 3 months after the full basic periodontal treatment. (Chart 1)

Results

The results was sufficient in the PD and the mobility comparing to the periodontal recording chart. (initial records vs. revaluation records) PRA was applied to monitored the patient’s situation. One record was taken 3 months after

Fig 2 Intraoral photos of initial stage.

Fig 3 Radiographic diagnosis including panoramic and periapical series.

Fig 5 PRA records after 3 months.

Fig 4 PRA records after 1 month.

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the Sc/Rp treatment (Figure 4) and another one was taken 6 months after the Sc/Rp treatment.(Figure 5) The plaque is recurred on the molars after 6 months. However, the bone loss is controlled and the decrease of tooth mobility is achieved. The patient was satisfied and appreciated the changes. In last, oral

hygiene education was provided for her to take care her teeth in future.

Reference

1. Genco R. et al., Periodontal Disease and Cardiovascular Disease, Epidemiology and

I N I T I A L V S . E VA L U AT I O N ( P R O B I N G D E P T H C H A N G E S )

Upper Teeth (Vestibular)

Upper Teeth (Palatal)

1 . 7 1 . 6 1 . 5 1 . 4 1 . 3 1 . 2 1 . 1 2 . 1 2 . 2 2 . 3 2 . 4 2 . 5 2 . 6 2 . 7

1 º 5 2 3 2 2 3 3 2 3 2 3 2 3 3 3 3 2 3 4 2 3 3 2 2 4 2 3 3 4 2 3 3 2 3 3 3 3 3 5 4 5 5

2 º 3 2 3 3 1 3 3 1 3 1 2 2 2 2 2 2 1 2 2 1 2 3 1 3 4 1 3 3 4 3 3 2 3 3 2 4 3 2 5 4 3 4

3 º 3 3 3 3 2 2 2 2 2 2 1 2 2 2 3 2 1 2 3 1 2 3 1 4 4 1 3 3 3 3 3 2 2 3 3 3 3 2 4 3 3 3

4 º 3 3 2 2 2 2 2 2 2 1 1 2 2 2 2 2 1 2 3 1 2 2 1 4 4 1 3 3 3 2 3 1 2 2 2 2 3 2 4 4 4 3

1 . 7 1 . 6 1 . 5 1 . 4 1 . 3 1 . 2 1 . 1 2 . 1 2 . 2 2 . 3 2 . 4 2 . 5 2 . 6 2 . 7

1 º 4 2 4 4 3 4 3 3 3 3 3 4 4 2 4 3 3 3 3 2 3 3 2 3 3 2 3 3 3 3 3 2 3 3 2 2 4 6 6 5 2 5

2 º 4 4 3 4 2 2 2 1 3 3 1 3 1 1 1 1 1 2 3 1 2 2 1 2 3 1 3 3 2 2 2 2 3 3 2 3 4 3 5 7 6 4

3 º 3 2 3 3 2 2 1 1 2 1 2 2 2 2 2 1 2 2 2 1 2 3 2 3 3 2 3 3 2 2 3 2 3 3 1 2 3 3 4 5 5 3

4 º 3 4 4 3 1 3 1 1 1 1 1 2 1 1 1 1 1 2 2 1 2 2 1 3 3 1 4 3 2 3 3 2 3 3 2 2 4 3 6 6 6 2

I N I T I A L V S . E VA L U AT I O N ( P R O B I N G D E P T H C H A N G E S )

Lower Teeth (Buccal)

Lower Teeth (Lingual)4 . 7 4 . 6 4 . 5 4 . 4 4 . 3 4 . 2 4 . 1 3 . 1 3 . 2 3 . 3 3 . 4 3 . 5 3 . 6 3 . 7

1 º 5 4 5 5 4 4 3 3 4 4 4 3 4 3 4 3 2 3 3 2 3 3 2 3 3 2 3 5 2 3 2 6 6 4 2 3 3 3 6 6 3 5

2 º 4 3 3 6 1 1 3 1 3 4 3 1 1 1 2 1 1 1 2 1 3 3 2 3 3 4 3 3 3 2 3 4 3 3 3 2 2 4 5 4 3 3

3 º 4 4 3 6 2 2 2 1 2 2 2 2 2 1 1 2 1 1 1 1 1 1 1 1 1 1 3 2 2 2 3 3 3 2 2 2 2 3 4 3 3 3

4 º 3 5 5 5 3 2 2 2 3 2 3 2 2 2 2 2 2 2 1 1 3 3 1 2 2 3 3 3 1 3 2 2 3 3 3 3 3 2 3 4 3 3

4 . 7 4 . 6 4 . 5 4 . 4 4 . 3 4 . 2 4 . 1 3 . 1 3 . 2 3 . 3 3 . 4 3 . 5 3 . 6 3 . 7

1 º 5 5 4 6 2 2 3 2 3 4 1 2 4 1 4 4 2 1 3 2 2 3 2 3 3 1 3 5 4 3 3 2 4 3 1 2 3 2 4 3 3 4

2 º 3 2 3 6 2 3 2 1 2 3 1 3 3 2 3 2 1 2 2 1 2 1 1 2 2 1 2 5 5 3 2 1 3 1 1 1 1 1 5 4 3 3

3 º 4 4 3 6 2 2 2 1 2 2 2 2 2 1 1 2 1 1 1 1 1 1 1 1 2 2 3 4 4 3 2 1 2 2 2 2 2 2 6 3 3 4

4 º 5 6 3 6 2 2 2 1 2 3 2 2 1 1 2 2 1 3 3 1 1 2 1 1 2 2 2 3 4 3 2 2 1 2 2 2 3 3 4 4 3 3

Chart 1 Improvement of Sc/Rp periodontal treatment. [Initial, 1 month, 3 months, 6 months]

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P o s s i b l e M e c h a n i s m s , J A D A , 2002;133;Jun:13-22

2. Lang N.P., Tonetti M.S., Periodontal Risk Assessment (PRA) for Patients in Supportive Periodontal Therapy (SPT), Oral Health & Preventive Dentistry, 2003;1:7-16

3. Khuller N., The Biofilm Concept and Its Role in Prevention of Periodontal Disease, Rev Clín Pesq Odontol., 2009;Jan/Abr;5:1:53-57

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Introduction

The malocclusions are the main esthetics, health, and functional problems around the world, also with dental cavity and periodontal disease. It is a incorrect or misalignment relation between the teeth of the two dental arches when the jaws close. Edward Angle, who is the father of modern orthodontics, was the first to classify malocclusion. He based his classifications on the relative position of the permanent maxillary first molar. Angle claimed that the anteroposter ior dental base relationship could be assessed reliably from first permanent molar relationship, as its position remained constant following eruption. In case where the first molars were missing, canine relationship is used.

The normal occlusion is based on the relation of the maxillary and mandibular teeth when the jaws are closed in centric relation which has to be wi thout s t ra in o f muscu la ture or displacement of the condyles in the fossa. The ideal occlusion is a hypothetical concept or a standard goal; on the other hand, the normal occlusion implies the the variations around the average value. However there are 6 keys to normal occlusion created by Lawrence F. Andrews which are:

Key I Molar relationship

The first of the six keys is molar relationship. The non-o r thodon t i c no rma l mode ls consistently demonstrated that the distal surface of the distobuccal cusp of the upper first permanent molar occluded with the mesial surface of the mesiobuccal cusp of the lower second molar.

Key II Crown angulation (tip)

The gingival portion of the long axes of all crowns was moredistal than the incisal portion.

Key III Crown inclination

It refers to the labiolingual or buccolingual inclination of the long axis of the crown, not to the inclination of the long axis of the entire tooth.

Key IV Rotations

It is that the teeth should be free of undesirable rotations.

Key V Tight contacts

It is that the contact points should be tight (no spaces). People who have genuine tooth-size discrepancies pose special problems, but in the absence of such abnormalities tight contact should exist. Without exception, the contact points on the non-orthodontic normals were tight.

Key VI Occlusal plane

The planes of occlusion found on the non-orthodontic normal models ranged from flat to slight curves of Spee. There is a natural tendency for the curve of Spee to deepen with time, for the lower jaw's growth downward and forward sometimes is faster and continues longer than that of the upper jaw, and this causes the lower anterior teeth, which are confined by the upper anterior teeth and lips, to be forced back and up, resulting in crowded lower anterior teeth and/or a deeper overbite and deeper curve of Spee.

Introduction to Orthodontic Dental ClassificationWei-Hua Chen

keywords: Angle Classification, dental relationship, malocclusion, occlusion, orthodontics

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The Angle’s classification is based on where the buccal groove of the mandibular first molar contacts the mesiobuccal cusp of the maxillary first molar: on the cusp (Class I, neutroclusion, or normal occlusion); distal to the cusp by at least the width of a premolar (Class II, distocclusion); or mesial to the cusp (Class III, mesiocclusion). Each class contains two or more types or divisions. (Figure 1)

ANGLE Class I: Neutroocclusion

Molar relationship:

The mesiobuccal cusp of the maxillary first pe rmanen t mo la r occ ludes w i th the mesiobuccal groove of the mandibular first permanent molar.

Canine relationship:

The mesial incline of the maxillary canine occludes with the distal incline of the mandibular canine. The distal incline of the maxillary canine occludes with the mesial incline of the mandibular first premolar.

Line of occlusion: - Altered in the maxillary and mandibular

arches.

- Individual tooth irregularities. (crowding/spacing/other localized tooth problems)

- Inter-arch problems (open bite/deep bite/cross bite)

Mesognathic:

Normal, straight face profile with flat facial appearance.

ANGLE Class II: Distoocclusion (overjet)

Molar relationship:

The molar relationship shows the mesiobuccal groove of the mandibular first molar is distally(posteriorly) positioned when in occlusion with the mesiobuccal cusp of the maxillary first molar. Usually the mesiobuccal cusp of maxillary first molar rests in between the first mandibular molar and second premolar.

Canine relationship:

The mesial incline of the maxillary canine occludes anteriorly with the distal incline of the mandibular canine. The distal surface of the mandibular canine is posterior to the mesial

Angle Class I Angle Class II Angle Class III

Fig 1 1st molar relationship between different Angle Classification. (modified from Netter's Head and Neck Anatomy for Dentistry)

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surface of the maxillary canine by at least the width of a premolar. Line of occlusion:

It is not specified but irregular, depending on facial pattern, overcrowded teeth and space needs.

Retrognatic: Convex face profile resulting from a mandible that is too small or maxilla that is too large.

Class II Malocclusion has 2 subtypes to describe the position of anterior teeth:

- Class II Division 1: The molar relationships are like that of Class II and the maxillary anterior teeth are protruded. Teeth are proclaimed and a large overjet is present.

- Class II Division 2: The molar relationships are Class II where the maxillary central incisors are retroclined. The maxillary lateral incisor teeth may be proclaimed or normally inclined. Retroclined and a deep overbite exists.

- Class II Sub-division: Class II molar relationship exists on one side and the other side has a normal Class I molar relationship.

ANGLE Class III: mesiooclusion (negative overjet)

Molar relationship:

The mesiobuccal cusp of the maxillary first permanent molar occludes DISTALLY (posteriorly) to the mesiobuccal groove of the mandibular first molar.

Canine Relationship:

Distal surface of the mandibular canines are mesial to the mesial surface of the maxillary canines by at least the width of a premolar. Mandibular incisors are in complete crossbite.

Line of occlusion:

It is not specified but irregular, depending on facial pattern, overcrowded teeth and space needs.

Prognathic:

Concave face profile with prominent mandible is associated with Class III malocclusion.

Class III malocclusion has 2 subdivisions:

- True class III malocclusion(skeletal): It is genetic in origin due to excessively large mandible or smaller than normal maxilla.

- Pseudo Class III malocclusion (false or postural): It occurs when mandible shifts anteriorly during final stages of closure due to premature contact of incisors or the canines. Forward movement of the mandible during jaw closure can also result from premature loss of deciduous posterior teeth.

- Class III Sub-division: Class III molar relationship exists on one side and the other side as a normal Class I molar relationship.

Conclusion

The orthodontists should know about the goal of the treatment based on the basic knowledge of the normal occlusion and also know how to distinguish abnormal or malocclusion, we should understand first what is normal. Cusp fossa relationship, normal overjet, deciduous, as well as mixed dentition occlusal changes and age related changes are very basic and important for us to know thoroughly. However, the successful orthodontic treatment involves many disciplines, not all of which are within our control. Achieving the final desired occlusion is the purpose of attending to the six keys to normal occlusion.

Reference

1. Norton, LA. The effect of aging cellular mechanisms on tooth movement. Dent Clin North Am. 1988;32:437–446.

2. Angle, EH. Classification of malocclusion. Dent Cosmos. 1899;41:248–264.Angle, EH. Classification of malocclusion. Dent Cosmos. 1899;41:350–357.

3. Anderson, GM. Practical orthodontics. in: 9th ed. CV Mosby, St. Louis; 1960:144–150.

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4. Case, CS. The teaching of orthopedic d e n t i s t r y . D e n t I t e m s I n t e r e s t . 1904;26:481–500.

5. Norton NS, Netter's Head and Neck Anatomy for Dentistry, 2nd, 2012.

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Introduction

Oral cancer is part of the head and neck cancer, which includes cancers of the mouth and the pharynx. Specifically, oral cancers includes lip, tongue, salivary glands, gum, mouth, pharynx, oropharynx and hypopharynx are included. More than 90% oral and pharynx cancers happen within the squamous cell carcinoma.

Epidemiology

Incidence/ Survival Rate

Oral cancer is the 11th most common cancer in the world, accounting for an estimated 263,000 new cases; 610,600 prevalent (old and new) cases; and 127,700 deaths annually in 2008.1 Based on data from US Surveillance, E p i d e m i o l o g y , a n d E n d R e s u l t s Program(SEER) 2 , the number of new oral cancer cases per 100,000 is 11.0 per year. This is growing trend while the incidence was 10.4 per 100,000, based on 1991 SEER data. For the future estimation, the estimated new cases is 45,780. The number of death per 100,000 is 2.5 per year, a slightly improvement of death rate. With 1991 SEER data, the death rate is 2.9 per 100,000 population. And the estimated deaths is 8,650. Around 1.1% of Americans will be diagnosed with developing oral cancer. The prevalence of oral cancer was estimated to be 291,108 people in 2012. Concerning of the 5 year relative survival rate, data from 1983-90 shows 52.5% while the rate increases to 63.2% from 2005-2011 data.2

Furthermore, while we take a closer look at the subgroup, oral and pharynx cancers accounts for 3% of all types of cancer in US. From the past studies, incident rates of male are 2 - 4 times than female in oral cavity cancer.2 The trend of increase in oral cancer rates happens in age groups of 30 - 54 and 55 - 69.2 The 5-year survival rate remains around 50-55% despite of the advanced development of surgery, radiation and chemotherapy.3 The non-significant improvement indicates oral cancers are often detected at late stages.4

In Taiwan, oral cavity cancer rates No. 6 in 2012 (carcinoma in situ is excluded). The total incidence case is 7,074 and the crude cancer incidence rate is 30.22%. However, there is a huge gender difference. 6462 male cases are reported, compared with 585 female cases. Oral cancer is the 4th in male while 15th in female. The mortality cases of male and female are 2,359 and 207 separately.5

Risk Factors in Developing Oral Cancer

Tobacco use There are studies support the association between oral cancers and tobacco use.3 Evidence of 5 - 9 times greater in oral cancers for smokers than non-smokers is provided.3 Those who continue to smoke are exposed to develop a 2 - 6 times risk of second malignancy of the upper aerodigestive tract than those who stop smoking.3

Alcohol Consumption Alcohol use has been identified as a major r isk factor for cancers of the upper

Brief Introduction of Oral Cancer and Related Oral Tumours Yeh-Chen Chen, BA, MA - TTY BioPharm

keywords: carcinoma, diagnosis, oral cancer, oral pathology, tumours, risk factors

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aerodigestive tract.3 Tobacco use and alcohol consumption are significantly interacted.2

Marijuana Use of Marijuana might potentially be a risk factor and lead to potential oral cancers for youths.3

Betel Nut In Asia, chewing betel nuts is very common. Usually betel nuts are wrapping by betel nut leaf with areas nuts, lime, sweeteners and condiments. The association between oral cancers and chewing betel nuts is widely studied and confirmed that it is the single greatest risk factor for developing oral cancers in Taiwan.3,5

Human Papilloma Virus (HPV) Probably linked with some oral cancers, like HPV-16 and HPV-18 have been studied to increase up to 22% and 14% of oral cancers, respectively.3

Pathology 6

The pathologies include four types of tumour, squamous cell carcinoma (90%, tongue and buccal cancer), salivary gland tumor (palate, mouth floor or tongue base), lymphoma and melanoma.

Signs and Symptoms

- Dysphagia. Hard to swallow. - Pain or ringing in the ears. - Trismus. Pterygoid muscle invasion. - Halitosis. - White, red or speckled patches develop in

the mouth, coming with unknown-sourcing bleeding, numbness, and loss of feeling.

- Persistent sores on the face, neck, or mouth that bleed easily and do not heal within 2 weeks.

- A soreness or feeling that something is caught in the back of the throat.

- A change in the way of teeth or dentures fitting together.

Diagnosis and Staging (Table 1)

- Leukoplakia - Erythroplakia - Oral Submucous Fibrosis

Treatment Planning

Treatments are different in stages. To treat the early stage of oral cancer, surgery is usually preferred to avoid late toxicities of RT. Concerning with locally advanced condition, chemoradiotherapy is the standard unless the addition of chemotherapy is not indicated dues to poor performance status or comorbid illness. For the recurrent and metastatic stage, palliative treatment is suggested.

Practices

In reality, it’s important to understand how dentists and physicians are aware of and diagnosis early through their daily practices. A survey is conducted to understand what dentists’ and physicians’ attitude and practice in detecting signs of oral cancer.4 A gap has been found in the knowledge and practices among practicers. The oral education is also be overlooked. Only 9% of physicians and 39% of dentists could understand and point out the two most common sites on which oral cancer happens. In addition, dentists and physicians perform better on identifying the most common symptoms of easy oral cancers. (57% of the dentists and 24% of physicians respectively)7 In another study, dentists averagely could identify about 5 out of 8 health history factors. 64% of the dentists could assess 5 or more items of the oral cancer health history index.4

Internationally, the WHO oral health program works very hard to facilitate countries to build their own capability in preventing and treating oral cancers. They have tried to bridge information gap between countries and developed global surveillance systems for oral cancer and risk factors.8

Reference

1. Sankaranarayanan R, Ramadas K, Subramanian S, Amarasinghe H, Johnson N, Prevention, Early Detection, and

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Treatment of Oral Cancer, Cancer: Disease Control Priorities, 3rd, vol.3, The International Bank for Reconstruction and Development / The World Bank, 2015;11.

2. Surveillance, Epidemiology, and End Results Program, National Cancer Institute, http://seer.cancer.gov/statfacts/html/oralcav.html.

3. Neville BW, Day TA, Oral Cancer and Precancerous Lesions, Ca Cancer J Clin, 2002;52:195-215.

4. Horowitz AM, Drury TF, Goodman HS, Yellowitz JA, Oral Pharyngeal Cancer Prevention and Early Detection - Dentist’s Opinions and Practices, JADA, 2000;Apr,131,453-462.

5. Health Promotion Administration Ministry of Health and Welfare Taiwan, Cancer Registry Annual Report 2012, 2015;Feb.

6. Surveillance, Epidemiology, and End Results Program, National Cancer Institute, Lip and Oral Cavity Cancer Treatment–Health Professional Version (PDQ®), http://www.cancer.gov/types/head-and-neck/hp/lip-mouth-treatment-pdq#section/_18.

7. Applebaum E, Ruhlen TN, Kronenberg FR, Hayes C, Peters ES, Oral Cancer Knowledge, Attitudes and Practices: A Survey of Dentists and Primary Care Physicians in Massachusetts, J Am Dent Assoc, 2009;140:461-467.

8. Peterson PE, Oral cancer prevention and control – The approach of the World ..., O r a l O n c o l ( 2 0 0 8 ) , d o i : 1 0 . 1 0 1 6 /j.oraloncology.2008.05.023.

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Stage T N M

0 Tis N0 M0

I T1 N0 M0

II T2 N0 M0

III T3 N0 M0

T1 N1 M0

T2 N1 M0

T3 N1 M0

IVA T4a N0 M0

T4a N1 M0

T1 N2 M0

T2 N2 M0

T3 N2 M0

T4a N2 M0

IVB Any T N3 M0

T4b Any N M0

IVC Any T Any N M1

Tab 1 Anatomic Stage/Prognostic groups.

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Introduction

Dental photography has become one of the most significant topics in this digital dentistry era. However, the challenges are often fall on the organizing and the management of the photos. Dentists may wonder how does the experts take their clinical photos, those they have shown in the presentation. Why look photos look different even if we are using the same camera same lens and even same settings. Sometimes, the technique is not just how to take photos. It may lead to how to make a great dental presentation.

Mask Technique

Mask technique is one of the common feature in the presentation design. It is a method for the designer to crop the pictures into the correct portions and shapes. The size could be modified and focused in kinds of matter. Simply double click the object, (pictures/ photos) which will turn the frame into the mask form. (Figure 1) All you need to do is drag and

edit the portions you wish to present. Proportions should be constrained in able to modify the pictures in the accurate definition.

This technique could not only helps you to have your picture in the way you want but also makes your audiences focus on the part you want them to look at. The following figure

Dental Presentation & Techniques using Apple Keynote

Part 1: Mask Techniques & Background DesignChen-Che Hung, DDS.

keywords: dental photography, digital, mask technique, keynote, presentation design

*the presentation design program is supported by EViDENT Academia. For course info: evident.academia@gmail.com

*original work is presented using Apple iWork System.

Fig 1 Mask technique could be activated by clicking “Edit Mask” or simply double click the object you are going to modify.

Fig 2 Same intraoral photo w/o Mask Technique, A. Original clinical photo is taken using 100mm f/2.8 Macro len, B. Exact clinical photo as Fig A adding Mask technique features to focus the actual treatment planning site.

A

B

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(Figure 2) has shown the difference before and after the usage of Mask Technique. Your clinical photo could be clean and clear on the part where you are going to explain the treatment.

Clean Background

For most of the intraoral photos, we use the dental retractor and intraoral mirror/ reflector to take the shot of records. However, if the clinical photos are focused on single tooth or just a few of teeth quadrants, the contraster is recommended for better photographic results. (Figure 3) The color black on the contraster will not reflect the shadows and “clean” your background into a nice monochrome form. It may be a delicate record especially when comparing different tooth color using VITA guides or any other tooth color matching system. The photo allows prosthodontist and the technicians to have the exact same vision without the disturbance of the color of tongue and the other soft tissue. The results make these selection of clinical photos look professional and have the audience focused on your work easily. (Figure 4)

Series of Dental Presentation & Techniques are presented in different volume of E7 Dental E -pub l i sh ing . Fu l l cou rse o f den ta l presentation design are available in the following session.

the article is supported by

For more information, please contact: evident.academia@gmail.com

Fig 4 A. Intraoral photo w/o the contraster. The disturbance of tongue appeared into the background. B. Intraoral photo using the contraster. It could highlight the missing teeth at the upper right quadrant easily.

A

B

Fig 3 Types of different intraoral contrasters according to the regions of the teeth. (products manufactured by Smile Line )

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Introduction

The first report describing the relation of osteonecrosis of the jaw and patients under bisphosphonates therapy was reported in 2003.1 Bisphosphonates can inhibit the activity of osteoclast to decrease the bone resorption and the rate of bone turnover ; thus, increase bone formation which are prescribed for bone disorders such as osteoporosis, multiple myeloma, Paget’s disease, or osteolytic bone metastases.2 However, it was mentioned in studies that bisphophonates could increase callus size and delay the regression in size in animal experiments after the fractures have recovered.3 Using bisphosphonate was suggested to delay the bone healing and decrease blood supply which increase the risk of osteonecrosis.4 This condition impeded implant placement osseointegration process and i ts prognosis .5 Besides, A non-b isphospoha te an t i reso rp t i ve agen t , denosumab, has been approved to treat osteoporosis by FDA in 2010. However, a case of osteonecrosis was then reported by Aghaloo and colleagues in a patient with cancer who received denosumab therapy.6 This medical condition is needed to be considered before implant placement.

Nowadays, there is greater tendency to take denta l implant as an opt ion of ora l rehabilitation. There were cases reported that dental implant placement as a kind of invasive treatment related to osteonecrosis for patients under bisphosphonate therapy or other antiresorptive medication used. To prevent osteonecrosis, dentists should be aware of the

all risks of dental implant placement for the patients receiving antiresorptive therapy and the way of prevention, or how to manage dental condit ion before patients take bisphosphonates.

It is critical for dental professionals to know that even the patients take the same medication which leads to different prognosis related to different disease or other combined therapy. It is important to have the knowledge of the antiresorptive medication, included drugs holiday, that the patient is taking for the preoperative management, so we will be able to evaluate the risks of being treated with implant . Therefore, pat ients can get appropriate dental treatment planning and lower risk of osteonecrosis of the jaw. In 2010, there was a case of osteonecrosis of the jaw reported that the patient with cancer is under denosumab therapy.7 The year after the panel of American Dental Association proposed that antiresorptive agent-induced ONJ as the term “ARONJ.” This term includes the cases of ONJ induced by bisphosphonates or by antiresorptive agents like denosumab.

Objective

The aim of this study is to identify the risks related to osteonecrosis of the jaw, and to describe the dental management and the prognosis of dental implant placement for patients receiving antiresorptive therapy.

Risk Factors of Osteonecrosis Considered before Implant Placement for Patient Receiving Antiresorptive Therapy

Part 1: Clinical Use & Risk Factors of ARONJ

Ming-Hsueh Lee, DDS.

keywords: antiresorptive, aronj, bisphospohonates, dental implants, osteonecrosis, pharmacology

*the article is modified to adjust for the template.

*original copy could be found in Dentistry Degree Project of Universidad CEU Cardenal Herrera.

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Methodology

In this study, two search engines were used, “Google Scholar”, and “Medline” search. Medline search engine were conducted in the resource offered by University Cardenal Herrera. The reference literatures were all published from 2000 to 2015. The key words used were: Bisphosphonates, dental implant, osteonecrosis, antiresorptive therapy, ADA, d e n t a l m a n a g e m e n t , A A O M S , o r pharmacology. A total of 713 articles were found and 42 were included in this review. The inclusion criteria was articles published from 2000 to 2015 and articles published in English. Most of articles were excluded because they were not published with full text available, articles published before 2000 and in different languages, and articles describing delivery of bisphosphonates locally around implants.

Clinical Use and Pharmacology Bisphosphonate

Bisphosphonate is an ana log o f pyrophosphate which is a normal metabolic product. It can be administrated both orally or intravenously. Bisphosphonate has two extra side chains comparing to pyrophosphonate where one can enhance the affinity to hydroxyapatite and the other determine the its potency. Unlike pyrophosphate which can be hydrolysed in many anabolic process, when bisphosphonate binds to hydroxyapatite crystals, it inhibits the function of osteoclast and bone remodeling.2

The half-life of the bisphosphonates in the circulation is within two hours which are secreted via the kidneys but which can be stored in bone in a very long time; probably a few years.8 That means what we are worried about is the residual bisphosphonates which would not disappear immediately once the pa t i en ts s topped tak ing i t . Bes ides bisphosphonate would attach to the bone with higher turnover rate like the jaw. It may contribute to the cause of the healing problem or osteonecrosis.9 The detailed mechanism is not very clear.

Bisphosphonates are separated to two group, n i t rogenous (zo led rona te ) and non-nitrogenous (etidronate). Non-nitrogenous bisphosphonate were taken up by osteoclast and which leads to apoptosis directly. Second and third generation of Bisphosphonates are nitrogenous ones which block a key enzyme in pathway of cholesterol, sterol, and lipid production and also lead to the apoptosis of osteoclast.10 Non-nitrogenous BP are mainly used for osteoporosis and Paget’s disease. In the other hand, nitrogenous are used primarily for cancer patients to control the related morbidities such as hypercalcemia, bone pain, or pathological fractures.11

Non BP Anti-resorptive Medication, Denosumab

Denosumab is an human monoclonal antibody that binds receptor activator of nuclear factor-kB ligand (RANKL) which inhibits the activity and the formation of osteoclast. It is an antiresorptive medication and is used for prevention of osteoporotic fracture mainly in postmenopausal women or skeletal related events in patients with bone metastases f rom sol id tumor. Unl ike bisphosphonate, denosumab has no high affinity to the bone which means it would not be stored in the bone for a long time. The half-life of denosumab is only 32 days.12 Incidence of Antiresorptive Medication-related Osteonecrosis of the Jaw

In 2007, an American Association of Oral and Maxillofacial Surgeons (AAOMS) Task Force published a definition for bisphosphonate-related ONJ (BRONJ) requiring the following clinical characteristics: current or previous treatment with a bisphosphonate, exposed bone in the maxillofacial region that has persisted for more than eight weeks, and no history of radiation therapy to the jaws.13 Therefore, the studies we used to analyze were the data from 2007.

Osteonecrosis can occur spontaneously, too. The culmulative incidence of avascular ONJ could arrive from 0.8% to 12% which

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developed more common in hypercalcemia.4 On the other hand, oral bisphosphonate related ONJ is extremely low. Data from 2008 2

showed 0.00007% to 0.04%. And a survey investigated patients with oral BP done in 2011.14 There were 8,572 survey respondents, and 1005 of them were examined. The result i n c l u d e d 9 c a s e s , 5 h a d o c c u r r e d spontaneously and 4 occurred in previous extraction sites. The prevalence of ARONJ is around 0.1%. There was one patient without exposed bone but resulted in implant failure. Considering the number of cases, the future studies should analyze the sample size more amplified.

In 2014, AAOMS published the prevalence of ONJ in different year exposure to antiresorptive medication and separate to oncology patients and osteoporotic ones. (Table 1) Except the risk factor of the duration of therapy, the more interesting thing is that for osteoporotic patients, IV BP therapy did not lead to higher incidence of ONJ compared to oral BP therapy. (Table 1) In addition, denosumab therapy seemed to keep the same level of risk with IV BP therapy whether in oncologic patients or osteoporotic ones.

Based on its characteristic of affinity to the bone, it is surprising to get this result.

Denosumab mimics the RANK (Receptor Activator of Nuclear Factor κ B) of the osteoclast and combines the RANKL on the osteoblast cell which inactivates function and differentiation of osteoclast and possible interferes more cell signal activities that we do not understand.15 There is no clarified answer for the fact that patients with cancer have a higher incidence of ONJ. The immune system, healing abilities, or concomitant therapy are suspected. It is a topic needed to investigate more.

Risk Factors for the Development of ARONJ

Medication

In 2014 AAOMS described the activity of several risk factors. First, medication use like bisphosphonates, corticosteroids and antiangiogenic agents are well recognized as the factors related to the ONJ. Some cancer patients were treated with zolendronate, for example, there was 50 to 100 times higher possibilities to get ONJ compared to the group of cancer patients treated with placebo.16 In addition, cancer patients with bisphosphonates therapy are administrated intravenously rather than oral administration which is the first line therapy for

Incidence of Osteonecrosis

Patients with Cancer

Osteoporotic Patients

Patients without Antiresorptive Therapy

0%-0.019% 0%-0.02%

With Oral BP Unknown 0.1% (1 year exposure) to 0.21% (more than four year)

With IV BP (Zolendronate)

0.6%(1 year ) 0.9%(2 year ) 1.3%(3 year )

0.017% (3 to 6 years exposure)

Denosumab 0.5%(1 year )

1.1%(2 year ) 1.1%(3 year )

0.04%

Tab 1 Data from AAOMS in 2014.16

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osteoporotic patients. IV bisphosphonates are the most predictive factors for the ARONJ. The reason is that bisphosphonate has low intestinal absorption.8 Oral taking is absorbed in stomach in passive diffusion and upper intestine.8 Intravenous administration is more efficacious in controlling bone remodeling but also increase the incidence of ONJ.

Concurrent treatment of bisphosphonate therapy combines with bevacizumab or sunitinib use is an additive effect on the incidence of ONJ.17,18 Bevacizumab targets VEGF and prevents the blood vessel growth. Sunitinib is a tyrosine kinase inhibitors (TKI) which can inhibit neoangiogenesis. It is assumed that antiangiogenic propertiy of these durgs predispose to the onset of ONJ.17,18

Oral or Chronic Disease

Concomitant oral disease such as periodontal disease, fistula, or periapical pathology can increase the risk. Stastical data showed that alveolar bone loss caused by periodontal disease is associated to the higher incidence of ONJ after extraction.19 Also in 2015, a systemic review mentioned that ONJ is assoc ia ted wi th b isphosphonate and denosumab, and the risk factors of which are glucocorticoid use, maxillary or mandibular bone surgery, poor oral hygiene, chronic inflammation, diabetes mellitus, ill-fitting dentures.20 Chronic diseases or diabetes me l l i t us a f f ec t immune sys tem and inflammation process.4 There is no clear mechanism to clarify but this theory is supported by several current reviews.

Genetic Factors

Genetic factors are being mentioned by many articles.4,15,16,21 Theoretically, all the genes affect angiogenesis or bone remodeling, collagen formation could be the risk factor. In these years, scientist are detecting the single nucleotide polymorphism (SNP) in different genes and see its relation. A study shows that SNP) in CYP2C8 (rs1934951) was identified as a risk factor of ONJ for multiple myeloma but this association can’t be identified in

patients with castrate-resistant prostate cancer.22 Another study shows that SNP in GFBP7 and ABCC4 possible implicated the increased risk of ONJ.23 However, SNP has still a susceptible role in the risk factor. Stastically, other factors like age and sex may place the patient under the risk of ONJ.24

Bacterial Infection

It is not sure the development of ARONJ. Some studies mentioned that bacterial infection probably is one of the cause.4,16,25,26 A study in 2013, which investigated 52 patients with bisphosphonate-related osteonecrosis of the jaw (BRONJ), decribed that one hundred percent of their patients are identified Actinomyces colonies in the exposed bone. It suggests that infection with actinomyces is a common denominator in BRONJ, regardless of administration route.27 Nevertheless, bacterial infection could also be the secondary infection and affects the prognosis of BRONJ.28 Dental Alveolar Operation

Tooth extraction is the most common predisposing factor to develop ONJ. An Australian study investigated 158 patients who got BRONJ.29 The result revealed that 72% of them developed ONJ after extraction. Following of many studies of BRONJ, ARONJ also can be triggered by extraction. The incidence of ARONJ after extraction is ranged from 52% to 61 % ; especially the patients with intravenous BP increased the risk as well from 16 fold to 33 fold.16 It is assumed that the antiresorptive medication also compromise the ability of wound healing.25,30 Since the accumulation of bisphosphonate could reach a higher amount every one more year, the capability of bone remodeling goes weaker which affects osteoclast, osteoblasts, and angiogenesis.25,30 Therefore, all the dental invasive treatment such as implant placement, periodontal therapy, endodontic treatment should be carefully evaluated. Because for the patients who takes antiresorptive medication could also trigger ONJ after dental operation.

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Duration of Taking Antiresorptive Therapy

It is difficult to know for how long taking antiresorptive therapy is risky. Not all of patients with this therapy are in high risk but it is hard to define the limitation. In these ten years, there were several literatures describing about the risk of long term usage. The increased risk of ONJ related to the duration of exposure to oral bisphosphonate were various from 3 to 5 years.16,30,31

An earlier study in 2007 indicated that 30 patients with oral BP therapy (alendronate) developed ONJ after 5.8 years exposure in average.32 On the other hand, 116 patients with IV BP therapy (zolendronate) devloped ONJ only after 9.3 months (zolendronate) to 14.1 months (pamidronate). With this limited sample size, oral BP increased to it risk to ONJ around 5 years and intravenous BP still showed a rapidly increased risk to ONJ around a year.

The cases were few and caused that the statistic result varies. A larger sample size was studied in 2011 done by FDA.33 The prevalence was 4 fold increased odds of risk after 4 years or longer exposure to oral bisphosphonate. The committe of AAOMS in 2014 also took this number as a risk-increasing border.16 The patients with intravenous bisphosphonate are associated with greater risk to ONJ. However, in the committee of AAOMS in 2014 did not mention for how long the duration of this therapy would increase the risk. It is stated that invasive process should be avoided if possible.16 Hence, the patients with bisphosphonates therapy over 4 years should be considered their increased risk to ONJ but they still can be received dental invasive process after drug holiday.

To the cancer patients with intravenous bisphosphonates therapy, dentists should consult physicist or oncologists to see the possibility of discontinuing antiresorptive therapy and then consider the duration of drug holiday for patients who really need dental invasive operation.6,16,21

There was no research concerning the relationship between increased risk and subcutaneous denosumab therapy. In 2011, ADA Council on Scientific Affairs suggested that the risk of ARONJ would be very low if the duration of therapy is within 2 years.6 On the other hand, considering the incidence which the former part mentioned, the culmulative inc idence of IV b isphosphonate and denosumab are similar, patients with malignancies should be avoided dental invasive process after both IV bisphosphonate and denosumab therapy.

Other Factors

Anatomic factors of the jaw is a risk factor as well. ONJ is more likely to happen in mandible than in maxilla.16 It is assumed the incidence was related to the alveolar bone turnover rate. It is said that the mandibular alveolar bone turnover rate is 10 times that of long bones like the tibia in a study.32 Age, denture use and tobacco are also related to the increased risk of ONJ.6,34

Reference

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2. Mar io t t i A . B i sphosphona tes and osteonecrosis of the jaws. Journal of dental education, 2008, 72.8: 919-929.

3. Aspenberg P. Bisphosphonates and implants: an overview. Acta orthopaedica, 2009, 80.1: 119-123.

4. Gupta S., Gupta H., Mandhyan D., & Srivastava S. Bisphophonates related osteonecrosis of the jaw. National journal of maxillofacial surgery, 2013. 4(2): 151–158.

5. Meira H. C., Rocha M. M, De Souza Noronha V. R., Aguiar D., Guimarães E., Sousa D, Rodiguez Neto D., Mandibular o s t e o n e c r o s i s a s s o c i a t e d w i t h b isphosphonate use af ter implant

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placement: Case report. Dental Press Implantology, 2013;7(2):107-14.

6. Hellstein J. W., Adler R. A., Edwards B., Jacobsen P. L., Kalmar J. R., Koka S., Ristic H. Managing the care of patients receiving antiresorptive therapy for prevention and treatment of osteoporosis: executive summary of recommendations from the American Dental Association Council on Scientific Affairs. The Journal of t h e A m e r i c a n D e n t a l Association, 2011,142(11), 1243-1251.

7. Aghaloo TL, Felsenfeld AL, Tetradis S. Osteonecrosis of the jaw in a patient on Denosumab. J Oral Maxillofac Surg 2010;68(5):959-963.

8. Drake M. T., Clarke B. L., & Khosla S. Bisphosphonates: mechanism of action and role in clinical practice. 2008, In Mayo Clinic Proceedings ;83(9).

9. D a h i y a V. , S h u k l a P. , G u p t a S . Bisphosphonates: An update to the general dentist. 2013 Dental Hypotheses, 4(2), 39.

10. Drake M. T., Clarke B. L., Khosla S. Bisphosphonates: mechanism of action and role in clinical practice.2008, In Mayo Clinic Proceedings ,83(9) 1032-1045.

11. Troeltzsch M., Woodlock T., Kriegelstein S., Steiner T., Messlinger K., Troeltzsch, M., Physiology and pharmacology of nonbisphosphonate drugs implicated in osteonecrosis of the jaw.2012, J Can Dent Assoc, 78(c85), 1-7.

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16. Ruggiero C, Salvatore L. Thomas B. D, John F, Reginald G, Tara A, Bhoomi M, Felice R . American association of oral and maxillofacial surgeons position paper on medication-related osteonecrosis of the jaw—2014 update. Journal of Oral and Maxil lofacial Surgery, 2014, 72.10: 1938-1956.

17. Ayllon J., Launay-Vacher V., Medioni J., Cros C., Spano J. P., Oudard S. , O s t e o n e c r o s i s o f t h e j a w u n d e r bisphosphonate and antiangiogenic therapies: cumulative toxicity profile? 2009 . Annals of oncology, 20(3), 600-601.

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19. Yamazaki T., Yamori M., Ishizaki T., Asai K., Goto K., Takahashi K., Bessho K. Increased incidence of osteonecrosis of the jaw after tooth extraction in patients treated with bisphosphonates: a cohort study 2012.International journal of oral and maxillofacial surgery, 41(11), 1397-1403.

20. Khan A. A., Morrison A., Hanley D. A., Felsenberg D., McCauley L. K., O'Ryan F. C o m p s t o n J . , D i a g n o s i s a n d Management of Osteonecrosis of the Jaw: A Systematic Review and International Consensus 2015.Journal of Bone and Mineral Research, 30(1), 3-23.

21. Ruggiero S. L., Dodson T. B., Assael L. A., Landesberg R., Marx R. E., Mehrotra B., American Associat ion of Oral and Maxillofacial Surgeons position paper on bisphosphonate-related osteonecrosis of the jaws—2009 update.2009 Journal of Oral and Maxillofacial Surgery, 67(5), 2-12.

22. English B. C., Baum C. E., Adelberg D. E., Sissung T. M., Kluetz P. G., Dahut W. L., Figg W. D.. A SNP in CYP2C8 is not associated with the development of bisphosphonate-related osteonecrosis of

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the jaw in men with castrate-resistant prostate cancer. 2010,Therapeutics and clinical risk management, 6, 579.

23. Nicoletti P., Cartsos V. M., Palaska P. K., Shen Y., Floratos A., Zavras A. I. , Genomewide pharmacogenet ics of bisphosphonate-induced osteonecrosis of the jaw: the role of RBMS3. 2012, The oncologist, 17(2), 279-287.

24. Ruggiero S., Gralow J., Marx R. E., Hoff A. O., Schubert M. M., Huryn J. M., Valero V. Practical guidelines for the prevention, diagnosis, and treatment of osteonecrosis of the jaw in patients with cancer.2006 Journal of oncology practice, 2(1), 7-14.

25. Saldanha S., Shenoy V. K., Eachampati P., U p p a l N . D e n t a l i m p l i c a t i o n s o f bisphophonate-related osteonecrosis , 2012 . Gerodontology, 29(3), 177-187.

26. Kos M. Luczak K. ,Bisphosphonates promote jaw osteonecrosis through fac i l i ta t ing bac ter ia l co lon isa t ion . 2009. Bioscience Hypotheses, 2(1), 34-36.

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29. Mavrokokki T., Cheng A., Stein B., Goss A. Nature and frequency of bisphosphonate-associated osteonecrosis of the jaws in Australia.2007 Journal of Oral and Maxillofacial Surgery, 65(3), 415-423.

30. Madrid C.,Sanz M. What impact do s y s t e m i c a l l y a d m i n i s t r a t e d bisphosphonates have on oral implant therapy? A systematic review. 2009 Clinical oral implants research, 20(s4), 87-95.

31. Saldanha S., Shenoy V. K., Eachampati P.,Uppal, N. Dental implications of bisphophonate-related osteonecrosis. 2012, Gerodontology, 29(3), 177-187.

32. Marx R. E., Cillo J. E., Ulloa J. J. Oral bisphosphonate-induced osteonecrosis: risk factors, prediction of risk using serum CTX testing, prevention, and treatment.2007 Journal of Oral and Maxillofacial Surgery, 65(12), 2397-2410.

33. Background Document for Meeting of Advisory Committee for Reproductive Health Drugs and Drug Safety and Risk Management Advisory Committee. United States. Food and Drug Administration. September 9, 2011; http://www.fda.gov/d o w n l o a d s / A d v i s o r y - C o m m i t t e e s /CommitteesMeet ingMater ia ls/drugs/D r u g S a f e t y a n -dRiskManagementAdvisoryCommittee/ucm270958.pdf Accessed February 10, 2014.

34. Vahtsevanos K., Kyrgidis A., Verrou E., Katodritou E., Triaridis S., Andreadis C. G., Antoniades K. Longitudinal cohort study of r isk factors in cancer pat ients of bisphosphonate-related osteonecrosis of t h e j a w, 2 0 0 9 . J o u r n a l o f C l i n i c a l Oncology, 27(32), 5356-5362.

35. Flichy-Fernández A. J., Alegre-Domingo T., González-Lemonnier S., Balaguer-Martínez J., Peñarrocha-Diago M., Jiménez-Soriano Y., Bagán-Sebastián J. V. Study of serum CTX in 50 oral surgical patients treated with oral bisphosphonates.2012 Medicina oral, patologia oral y cirugia bucal,17(3).

36. Wang H. L., Weber D., McCauley L. K. Effect of long-term oral bisphosphonates on implant wound healing: literature review and a case report 2007.Journal of periodontology, 78(3), 584-594.

37. MEIRA H. C., ROCHA M. M., De Souza NORONHA V. R. A. , AGUIAR D. , Guimarães E., SOUSA D., RODRIGUES NETO D. J. Mandibular osteonecrosis associated with bisphosphonate use after imp lan t p l acemen t : Case repo r t . 2013 Dental Press Implantology, 7(2).

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38. Abrahamsen B., & Einhorn T. A. Beyond a reasonable doubt? Bisphosphonates and atypical femur fractures,2012. Bone, 50(5), 1196-1200.

39. Kim Y. H., Lee H. K., Song S. I., Lee J. K. Drug holiday as a prognostic factor of medication-related osteonecrosis of the jaw. 2014, Journal of the Korean Association of Oral and Maxillofacial Surgeons, 40(5), 206-210.

40. Fugazzotto PA, Lightfoot WS, Jaffin R, Kumar A. Implant placement with or without simultaneous tooth extraction in patients taking oral bisphosphonates: postoperative healing, early follow-up, and the incidence of complications in two private practices, 2007, J Periodontol.;78(9):1664-9.

41. Grant BT, Amenedo C, Freeman K, Kraut RA. Outcomes of placing dental implants in patients taking oral bisphosphonates: a review of 115 cases, 2008, J Oral Maxillofac Surg. ; 66(2):223-30.

42. Bell B. M.,Bell R. E., Oral bisphosphonates and dental implants: a retrospective study, 2008, Journal of Oral and Maxillofacial Surgery, 66(5), 1022-1024.

43. Koka S., Babu N. M. S., Norell A. Survival of dental implants in post-menopausal bisphosphonate users.2010 Journal of prosthodontic research,54(3), 108-111.

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