toothwear · 2013. 7. 23. · utilising the charted odontogram to assess patient risk 72 summary 73...

TooThwearTHE ABC of THE Worn DEnTiTion

edited by F. Khan and w.G. Youngforeword by A. Lussi

This is one of the first books to provide a clinically focussed account of the diagnosis, prevention and treatment of all forms of toothwear. Bringing together the latest research, it is compiled by international leaders in the field to create an essential clinical guide for dental practitioners. The book covers all forms of toothwear and dental erosion, and is presented in a practical format that allows for ease of reference and helps assimilate clinical information quickly. it defines the stages of toothwear, provides schematic approaches to allow better understanding of the key role that saliva plays, and highlights the differences between acid erosion and dental caries. importantly for clinicians, it provides a framework for developing best practice management strategies by discussing diagnostic skills, treatment planning and therapeutic modalities.

An essential resource based on a solid research platform, this book will provide dental clinical professionals with the missing links they seek to diagnose, prevent, manage, restore and rehabilitate the worn dentition more confidently. it will be of value to dentists, dental therapists, dental hygienists, and students in these areas.

Key Features

• Covers all forms of toothwear and dental erosion across all age-groups

• includes discussion of best practice management strategies

• Discusses aetiology, diagnosis, prevention and treatment in a clinical context

• Contains many full colour clinical illustrations and schematic conceptualisations

• Brings together the latest clinical views and research with a wide range of international contributors

Related Titles

Comprehensive Occlusal Concepts in Clinical Practice irwin M. Becker iSBn 9780813805849

Dry Mouth, The Malevolent Symptom: A Clinical Guide Edited by Leo M. Sreebny and Arjan Vissink iSBn 9780813816234

Cover design: www.hisandhersdesign.co.uk

TooThwearThe aBC oF The worn DenTiTion

edited by F. Khan and w.G. Young

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P1: SBT Trim: 246mm X 189mmBLBK366-FM BLBK366-Khan May 11, 2011 11:4 Printer Name: Yet to Come


Toothwear: The ABC of theWorn Dentition


Toothwear: The ABC ofthe Worn Dentition

Edited by

Dr Farid Khan

and

Professor William George Young

A John Wiley & Sons, Ltd., Publication


This edition first published 2011 by John Wiley & Sons LtdC© 2011 John Wiley & Sons Ltd

Wiley-Blackwell is an imprint of John Wiley & Sons, formed by the merger of Wiley’s global Scientific, Technical and Medicalbusiness with Blackwell Publishing.

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Designations used by companies to distinguish their products are often claimed as trademarks. All brand names and productnames used in this book are trade names, service marks, trademarks or registered trademarks of their respective owners. Thepublisher is not associated with any product or vendor mentioned in this book. This publication is designed to provideaccurate and authoritative information in regard to the subject matter covered. It is sold on the understanding that thepublisher is not engaged in rendering professional services. If professional advice or other expert assistance is required, theservices of a competent professional should be sought.

Library of Congress Cataloging-in-Publication Data

Toothwear : The ABC of the worn dentition / edited by Dr Farid Khan and Professor William George Young.p. ; cm.

Includes bibliographical references and index.ISBN 978-1-4443-3655-9 (paperback : alk. paper)

1. Teeth–Abrasion. I. Khan, Farid, editor. II. Young, William George, 1939- editor.[DNLM: 1. Tooth Wear–diagnosis. 2. Dental Restoration, Permanent–methods. 3. Tooth Wear–prevention & control.

4. Tooth Wear–rehabilitation. WU 210]RK307.T66 2011617.6′075–dc22 2010047726

A catalogue record for this book is available from the British Library.

This book is published in the following electronic formats: ePDF 9781444341119; ePub 9781444341126; Mobi 9781444341133

Set in 9.5/12 pt Palatino by Aptara R© Inc., New Delhi, India

Printed in Singapore

1 2011

http://www.wiley.com/wiley-blackwell


Contents

Contributors ix

Foreword: Adrian Lussi xi

1 The multifactorial nature of toothwear 1Farid Khan and William G. Young

Toothwear processes 1Saliva protection 4Intrinsic and extrinsic acids 4Examination of facial, extraoral and intraoral soft tissues 4Toothwear in children 9Toothwear and dental caries 9Toothwear – A multifactorial process 12References 14

2 Diagnosis and management of toothwear in children 16W. Kim Seow and Sue Taji

Clinical presentations of toothwear in children 16History-taking, assessment and diagnosis 20Children at increased risk for toothwear 21Management of toothwear in children 25The global perspective 32References 32

3 Childhood diet and dental erosion 34Louise Brearley Messer and William G. Young

Dental erosion in children, adolescents and teenagers 34Concerns of patients and parents 34

v


vi Contents

Clinical appearance of dental erosion 35Dietary findings in dental erosion 35Dental erosion as a lifestyle issue 37Recommendations for patients to reduce erosion 39Dental erosion and dental caries compared 41Dietary counselling for children and adolescents 42The key messages 48References 48

4 The oral presentation of toothwear in adults 50Farid Khan and William G. Young

Diagnostic modalities 50Surface susceptibility of toothwear and site specificity of dental caries 52The clinical presentation of toothwear 53Charting toothwear 65Application of The Stages of Wear to diagnosing toothwear 71Utilising the charted odontogram to assess patient risk 72Summary 73References 73

5 Salivary protection against toothwear and dental caries 75Colin Dawes

Factors causing toothwear 75Factors causing dental caries 75Why does a tooth dissolve in acid? 77Sources and components of saliva relevant to toothwear and caries 78Conclusions 86References 87

6 Dental diagnosis and the oral medicine of toothwear 89William G. Young and Colin Dawes

The approach 89Mild, moderate or severe toothwear 89Complaint/discovery 90Development 90Attrition 91Abrasion 92Toothbrushing 92Oral hygiene 93Diet erosion 93Gastric erosion 94Sports and social 94Medical 95Addictions, fixations and confidentiality 95The cases 96


Contents vii

Summary 108References 108

7 Preventive and management strategies against toothwear 111Farid Khan and William G. Young

Aiming prevention at all ages 111Lifestyle, health and environmental risk factors 114The WATCH strategy 117Adjunctive products 117Diet diaries and review 126Patient’s reporting sensitivity 126Treatment planning 128The review appointment 129Summary 130References 131

8 Measurement of severity and progression of toothwear 134William H. Douglas and William G. Young

Non-parametric or semi-parametric approaches 134Parametric measurement of toothwear 135Reporting toothwear 137The cases 145References 151

9 Biomaterials 153Stephen C. Bayne

Introduction 153Overview of biomaterials wear 157Clinical wear performance of biomaterials 161Comments on special wear situations 165References 167

10 The role of toothwear in occlusion 168Anders Johansson and Gunnar E. Carlsson

Development of occlusion 170Patterns of toothwear on anterior palatal and posterior occlusal surfaces

and Angle’s classification 176Conclusion 179References 180

11 Restoration of the worn dentition 182Ian Meyers and Farid Khan

To restore or not to restore is a central question 182Pre-restorative treatment – preparation and planning 183


viii Contents

Restorative challenges 184Restoring the stages of wear 184Patient demands, aspirations, aesthetics and case selection 187Conservative restorative options for partial or full-mouth occlusal reconstruction 188Summary 202References 202

12 Rehabilitation of the worn dentition 205Ridwaan Omar and Ann-Katrin Johansson

Principles and strategies for rehabilitating worn dentitions 206Conclusion 226References 226

Index 229


Contributors

Stephen C. BayneProfessor and ChairCariology, Restorative Sciences, and

EndodonticsSchool of DentistryUniversity of MichiganAnn Arbor, MI, USA

Gunnar E. CarlssonEmeritus ProfessorDepartment of Prosthetic DentistryInstitute of OdontologyThe Sahlgrenska AcademyUniversity of GothenburgGoteborg, SE, Sweden

Colin DawesEmeritus ProfessorDepartment of Oral BiologyFaculty of DentistryUniversity of ManitobaWinnipeg, MB, Canada

William H. DouglasEmeritus ProfessorSchool of DentistryUniversity of MinnesotaMinneapolis, MN, USA

Anders JohanssonProfessorDepartment of Clinical Dentistry –

ProsthodonticsFaculty of Medicine and DentistryUniversity of BergenBergen, Norway

Ann-Katrin JohanssonAssociate ProfessorSpecialist in Pediatric DentistryChairmanDepartment of Clinical Dentistry – CariologyFaculty of Medicine and DentistryUniversity of BergenBergen, Norway

Farid KhanDirectorQueensland Dental GroupTM

IndooroopillyBrisbane, Queensland, Australia

Adrian LussiProfessorDirectorDepartment of Preventive, Restorative, and

Pediatric Dentistry

ix


x Contributors

University of BernFreiburgstrasse, Bern, Switzerland

Louise Brearley MesserEmeritus ProfessorPaediatric DentistryMelbourne Dental SchoolUniversity of MelbourneVictoria, Australia

Ian MeyersProfessorSchool of DentistryUniversity of QueenslandBrisbane, Queensland, Australia

Ridwaan OmarProfessorDepartment of Restorative SciencesHead of ProsthodonticsFaculty of DentistryKuwait UniversitySafat, Kuwait

W. Kim SeowProfessorDirectorCentre for Paediatric Dentistry Research

and TrainingSchool of DentistryUniversity of QueenslandBrisbane, Queensland, Australia

Sue TajiSpecialist in Paediatric DentistryBrisbane, Queensland, Australia

William G. YoungAssociate ProfessorOral PathologistBrisbane, Queensland, Australia


Foreword

In recent decades there has been a remarkablecaries decline in developed countries. This ismainly due to improved oral hygiene and flu-orides. During the same period, people withhigh awareness of health have changed theirdietary habits. Nowadays, more acidic drinksand juices are consumed compared with a fewdecades ago. These changes and other factorshave led to an increased loss of dental hard tis-sue such as toothwear.

Toothwear is a multifactorial condition ofgrowing concern to the clinician. Only a fewbooks have been published, collecting com-prehensive knowledge about this subject. Thepresent book is one of them.

The 12 chapters of the book cover impor-tant aspects of toothwear, from childhood toadults. It covers not only the multifactorial na-ture of toothwear but also the diagnosis andprevention of it. Four chapters are dedicatedto restorative aspects, dental materials, occlusalproblems and rehabilitation procedures.

The task of bringing together the currentknowledge of toothwear is not easy, but hasbeen perfectly accomplished in this book. Itgives guidelines to practitioners, dental stu-dents and teachers.

Professor Adrian LussiUniversity of Bern

Switzerland

xi

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1The multifactorial nature of toothwear

Farid Khan and William G. Young

TOOTHWEAR PROCESSES

Attrition, erosion and abrasion describe wearprocesses (Fig. 1.1). Attrition involves two-surface (tooth-to-tooth) wear. Erosion, less com-monly referred to as corrosion, results fromacidic dissolution of mineralised tooth struc-ture. Abrasion on a surface comprises wearfrom externally applied particles or objects.

When a patient presents with a heavilyworn dentition (Fig. 1.2), the clinician con-siders whether the toothwear processes haveinvolved elements of attrition, erosion orabrasion. Whilst the wear facets identifiedon the lower anterior teeth suggest attri-tion, numerous high margins on restorationspoint to involvement of erosion, removingtooth structure adjacent to these restorations.Demineralisation of tooth structure furtherpredisposes to abrasion as evident in cervicalregions, many of which have previously beenrestored. Since placement of these restorations,toothwear processes have continued. This casehighlights that interrelationships exist between

toothwear processes which potentiate oneanother.

Although the processes of attrition, erosionand abrasion can be simulated under labo-ratory conditions, clinically these processesdo not occur independently (Fig. 1.3). Thecoarse particles of foods in primitive dietspotentiated the wear facets (Young 1998) ofattrition by abrasion (Fig. 1.3a). Modern di-ets lack such abrasives; however, oral acidsthat cause erosion demineralise enamel anddentine, potentiating attrition and abrasion(Figs. 1.3b & c). A recent literature review onerosion noted that dietary acids are consideredby many researchers probably to be the mostcommon cause of acid erosion (Bartlett 2009).Exaggerated wear facets are the first sign oferosion-potentiated attrition in young adults’permanent teeth. Toothbrush and toothpastecombinations are important considerations,particularly in patients in whom dental ero-sion has also been identified, for abrasivenessbecomes potentiated when tooth structure isdemineralised. A combination of these two

Toothwear: The ABC of the Worn Dentition, First Edition. Edited by Farid Khan and William George Young.C© 2011 John Wiley & Sons, Ltd. Published 2011 by John Wiley & Sons, Ltd.

1


2 Toothwear: The ABC of the Worn Dentition

(a) Attrition (b) Erosion (c) Abrasion

pH

Figure 1.1 The processes of attrition, erosion andabrasion: (a) Attrition is wear between two tooth sur-faces. (b) Erosion is tooth surface loss from acids.(c) Abrasion is loss of tooth surface from a foreignbody.

(a)

(b) (c)

Figure 1.2 Three processes of toothwear are reported in this case: (a) Incisal attrition on incisors. (b) Occlusalerosion on premolars and molars and around amalgam restorations. (c) Various cervical regions have beenrestored previously, with further loss of tooth structure since the time of restoration. (From Young, 2001, withpermission of Dentil Pty Ltd.)

processes can lead to severe toothwear (Fig.1.4). When used on demineralised tooth struc-ture, abrasion from routine use of standardtoothbrushes and toothpaste formulations issignificant, whilst in the absence of erosion, itis considered to be minimal (Addy 2005). At-tritional facets and cuspal-cupped lesions canbe found on the same tooth (Fig. 1.5). This sug-gests that the wear facet worn by the mesiobuc-cal cusp of the upper first molar has been po-tentiated or exaggerated by occlusal erosionthat has produced the cuspal-cupped lesions.


The multifactorial nature of toothwear 3

(b) Erosion potentiating

attrition

pH

(a) Abrasionpotentiating

attrition

(c) Erosionpotentiating

abrasion

pH

Figure 1.3 Interactions of abrasion, attrition anderosion in toothwear: (a) Acids soften surfaces po-tentiating attrition. (b) Acids soften surfaces potentiat-ing abrasion. (c) Abrasion from particles harder thanenamel and dentine potentiates attritional wear.

Moreover, erosion has produced the shallowcervical lesion on the buccal surface of thistooth possibly potentiated by toothbrush abra-sion.

These interrelationships between attrition,erosion and abrasion highlight that multifacto-rial processes create a worn dentition (Fig. 1.6).Each patient has a variation in the involve-ment of attrition, erosion and abrasion. In manypatients, it is predominantly underlying ero-sion that potentiates the secondary effects of at-trition and abrasion. Appreciating that differ-ent processes are working concurrently allows

Figure 1.4 Facial surfaces of the central incisors aredevoid of enamel in a 31-year-old female gymnast.The dentine is deeply grooved by toothbrush abrasion.The approximal enamel is remarkably intact. Scanningelectron microscopy (SEM) (Bar = 1 mm). (From Khanet al., 1999, with permission from the Australian Den-tal Journal.)

Figure 1.5 An attritional wear facet (F) on a buccalcusp of a lower first permanent molar. On all cuspsare the cupped lesions of erosion not necessarily asso-ciated with attrition. A shallow buccal cervical lesion(C1) is also present on this tooth (Bar = 1 mm). (FromYoung & Khan, 2009, with permission from ErosionWatch Pty Ltd.)

the clinician to focus diagnostic, preventiveand management strategies on all three aeti-ologies. Thus, tooth tissue loss will continue ifits multifactorial nature is not recognised andaddressed.

ErosionAttrition

Abrasion

Toothwear

Figure 1.6 Toothwear is best conceptualised as acombination of erosion, attrition and abrasion.



(a) Saliva lubricationreduces

attritional wear

(b) Saliva buffers,clears and protects

against acids

pH

Figure 1.7 Saliva offers protection against attri-tional wear (a) through lubrication and (b) by raisingthe pH through buffering and clearance of acids thatproduce erosion.

SALIVA PROTECTION

Saliva is central in counteracting and balanc-ing toothwear processes, and tooth surfaces areprotected against toothwear by salivary buffer-ing capacity, salivary pellicle, acid clearanceand washing of the dentition (Dawes 2008). Theunstimulated flow rate of saliva and salivarybuffering capacity have been directly associ-ated with dental erosion (Zero & Lussi 2005).Both mucous and serous saliva protect againstattritional wear through lubrication of the teethand areas of interarch contact, as well as neu-tralise acids within the oral environment. Salivaalso reduces demineralisation by its content ofcalcium and phosphate (Fig. 1.7).

INTRINSIC ANDEXTRINSIC ACIDS

Acids that demineralise teeth are extrinsic di-etary or intrinsic, gastric or plaque in origin.Dietary acids most commonly implicated areascorbic acid (vitamin C), citric acid, sodiumcitrate and orthophosphoric acid, because theseare used as flavours and preservatives in mostacidic beverages. So, soft (Johansson et al. 2002),sports (Milosevic 1997) and energy drinks aresources, with other acids in wines. Hydrochlo-ric acid from gastric juice is the usual intrinsicacid implicated in dental erosion and toothwear

(Scheutzel 1996). A study examining 19 profes-sional wine tasters found mild-to-severe dentalerosion and found the subjects with severe den-tal erosion also to have had a history of gastritisor reduced salivary flow rate and/or bufferingcapacity (Wiktorsson et al. 1997).

The case presented in Fig. 1.8 shows thetoothwear of an elite athlete, 24 years of age.His lifestyle placed him at risk of developingsevere toothwear. His rigorous training regimesreduced the salivary protection of his denti-tion. Subsequent rehydration with acidic sportsdrinks at times of dehydration affected hisdentition. Acidic beverages and foods are im-portant contributors to erosive toothwear inmany individuals (see Chapter 3), given theircommon availability, and yet the pH alone isinsufficient to determine their erosive potential,which is instead influenced by a large range ofvariables including consumption patterns, ad-hesion and chelating properties of salivary pro-tection, and swallowing and clearance patterns(Lussi et al. 2004). Frequent episodes of reducedsaliva protection and acid drinks resulted insevere loss of enamel and dentine in thisyoung adult, principally from dental erosion.Dental erosion in athletes is a growing con-cern (Sirimaharaj et al. 2002); however, manychildren and young adults also frequentlyconsume such beverages. Increased consump-tion of sports drinks and acidic beverages, dur-ing the day and also during heavy exercise, islikely contributing to the increasing dental ero-sion prevalence (ten Cate & Imfeld 1996), par-ticularly in young individuals.

EXAMINATION OF FACIAL,EXTRAORAL AND INTRAORALSOFT TISSUES

The multifactorial nature of toothwear is fur-ther highlighted by benefits from identifyingfacial, extraoral and intraoral soft tissue fea-tures even before a worn dentition is assessed.



(a) (b)

(c)

Figure 1.8 A 24-year-old male patient with a long history of athletic training at a professional level. Acidicbeverage rehydration frequently occurred subsequent to intense physical training sessions, at times of dehydrationand low salivary protection. This allowed rapid loss of tooth structure to occur. (a) Near exposures of the pulpaltissues are evident on the lingual surfaces of the maxillary anterior teeth. (b) Extensive areas of erosion havenotably affected his first molar teeth. (c) Cervical lesions are evident on the maxillary and mandibular buccalsurfaces of canine and lateral incisor teeth. (From Young, 2003b, with permission of Dentil Pty Ltd.)

Much can be learned of lifestyles, general med-ical conditions, temporomandibular joint (TMJ)disorders and salivary gland pathology by con-sidering signs and symptoms relevant to tooth-wear. For the clinician, a schematic approachfor examination of facial, extraoral and intrao-ral features adds diagnostic information rele-

vant to the aetiology of the patient’s condition.Icons applicable to these features are includedto trigger the clinician’s mind during the exam-ination (Fig. 1.9). These icons are used through-out this text alongside clinical photographs ofinteresting cases to indicate additional findings.Visual inspection and manual palpation are all



Gingiva/Palate

Tongue

III III

Eye EarLipsSkinHair

F A C E

Submandibular gland Lymph node

N E C K

Parotid gland

Occlusion Lining mucosa

TMJ muscles

Figure 1.9 The icons for examination of the face, the oral soft tissues and the teeth, as utilised on standardisedexamination sheets applied clinically for patients with worn dentitions. (From Young & Khan, 2009, with permissionof Erosion Watch Pty Ltd.)

the clinical skills the clinician needs to makeadditional important observations. The iconsremind us to record the relevant ones. Theodontogram (Fig. 1.9, centre) describes eachtooth as an icon. Three surfaces of each toothare represented, as approximal surfaces are al-most never significantly affected by toothwearand consequently the clinician need only record

the severity of wear on the occlusal and cer-vical surfaces illustrated. Detailed methods forexamination of the worn dentition are providedin Chapter 4.

Eye contact is the first event ofexamination. Trust and empathyare established and concern is

communicated between the patient and the



Figure 1.10 Lacrimal duct aplasia with epiphora incongenital dysfunction of major salivary glands. (FromYoung et al., 2001, with permission of Oral Surgery,Oral Medicine, Oral Pathology.)

clinician. Yet, for the clinician concerned withtoothwear, the patient’s eyes can communi-cate insights into medical conditions and syn-dromes that explain why the patient is at risk.The lacrimal glands produce tears which havemany similarities to saliva. Hence, conjunctivi-tis and dry mouth in Sjogren’s syndrome areobvious examples wherein both lacrimal glandsand saliva fail to protect mucosal surfaces. Ex-amination of the eye and discussion with thepatient might reveal lacrimal duct aplasia withepiphora (Fig. 1.10), as found in this patientwith congenital dysfunction of major salivaryglands, who experienced severe dental erosion(Young et al. 2001).

The skin of the lower lip is partic-ularly susceptible to sun damage,

as the vermilion border is usually not pig-mented in Caucasian people in the subtropics.Outdoor work frequently damages the pa-tient’s skin (Fig. 1.11). Actinic cheilosis is oftenidentified on the lower lips of patients whoare regularly exposed to the sun in their sportsactivities and outdoor occupations. This mayindicate a lifestyle involving frequent work-related dehydration, which by reducing salivaprotection against acids in the mouth, putspatients at risk of toothwear.

Figure 1.11 Sun-affected damaged lip from a life-time of dehydrating outdoor work in a 60-year-old con-struction worker with a heavily worn dentition.

The patient’s facial hair gives clues to hor-monal status. Thus, lanugo – a fine, fair, fa-cial hair – is noticed at puberty in both boysand girls. It is also found in patients with thehormonal upsets of anorexia nervosa and as aresult of hormone replacement therapy at themenopause. Thus, lanugo may alert the clini-cian to consider this further when compiling aclinical history.

Evidence of skin irritation or presenceof eczema (Fig. 1.12) may be evidentperiauricularly or on any part of thebody and may suggest syndromic as-

sociations as in cases of hereditary ectodermaldysplasia. Hearing loss in young patients maybe part of a syndrome. In congenital rubellasyndrome, the patient has glaucoma, bilateralhearing aids, and a congenital heart defect as atriad (Young et al. 2001). This triad of signs hasconsiderable relevance to dental treatment, asconsidered further in Chapter 6.

The TMJ can click, or evenlock, when the patient opens andcloses their mouth. The musclesof mastication may be painful to

palpation in TMJ pain–dysfunction syndrome.When the teeth are clenched, the masseter mus-cles tense and become prominent. Behind thismuscle and in front of the ear lies the preauric-ular crease (Fig. 1.12).



Figure 1.12 Eczema around and behind the ear ofa patient with ectodermal dysplasia.

When the parotid glands are en-larged and prominent, the preau-ricular creases are obliterated. Thefirm glands can be felt behind theclenched masseter muscles, denot-

ing sialadenosis.Indentations of the lateral bordersof the tongue indicate that the pa-tient presses their tongue against

the lingual surfaces of the teeth during para-functional habits (Fig. 1.13).

The lining mucosae are studdedwith minor mucous glands. Lin-ing mucosae cover the undersur-faces of the tongue, the floor ofthe mouth, the labial sulci and the

soft palate. When saliva covering these surfacesis viscous, frothy and white, it is slow-flowingsaliva. When thrush (Candida albicans) is foundon these surfaces, it indicates loss of immu-nity conferred by saliva against this micro-organism. Linea alba, white calluses on the buc-

Figure 1.13 White lines on the buccal mucosa(linea alba) and lateral indentations of the tongue indi-cate parafunctional habits. (From Young, 2001b, withpermission of Dentil Pty Ltd.)

cal mucosae along the occlusal plane, occurs inpatients who have parafunctional habits, suchas bruxism (Fig. 1.13).

Gingivitis and gingival recessionmay indicate poor oral hygiene and

periodontal changes or toothbrush trauma. Thegingivae and the hard palate contain virtuallyno salivary gland tissue, except at the back ofthe vault where the hard palate joins the softpalate.

Occlusion of the teeth may showdeep overbite, overjet or open bitebetween the anterior teeth. Cross-

bite may be found in the posterior quadrants.Angle’s class I, II or III malocclusion is delin-eated from the relationship of the mesiobuccalcusp of the maxillary first molar to the mesio-and distobuccal cusps of the mandibular firstmolar. All variations in occlusion have signifi-cance for finding exaggerated wear facets.

The submandibular glands, whenenlarged, are best appreciated bybimanual palpation. The fingersof one hand are placed below the



lower border of the mandible and pressed intothe submandibular triangle of the neck. A fin-ger of the other hand feels along the lingual sul-cus in the floor of the mouth. Normal salivaryglands are difficult to feel, but the volume ofenlarged, slightly firm submandibular glandscan be appreciated both in the floor of themouth, behind the mylohyoid muscle, and inthe submandibular triangle. This enlargementis sialadenosis. It is neither a lumpy tumour nora tender inflammation. A tender lump may bean inflamed lymph node within the gland.

The lymph nodes of the neck are pal-pated to rule out inflammation or tu-mour. In sialadenosis, the lymph nodes

are normal.The thyroid gland is palpatedas part of the neck examination.Changes in this gland relate to hor-monal changes and therapy, but no

specific link to salivary gland dysfunction hasbeen made.

TOOTHWEAR IN CHILDREN

Few of these facial features and salivary glandor soft tissue changes observed in adults arefound during the examination of the child-patient with toothwear. Eye and ear changes arerare. The skin of the face and lips may showlanugo found at puberty in boys and girls. Themajor salivary glands are underdeveloped inyoung children. They may be affected at pu-berty, but are more usually normal. The tem-poromandibular joints and muscles of masti-cation are affected only if severe trauma hasaltered their growth. Tongue indentations andlinea alba are rarely found, even in childrenwhose parents give testimony of night grindinghabits. Rarely oral thrush may be found on thetongue, palate and gingivae.

Consequently, the best indicator of excessivetoothwear in children is a reduction in occlusalvertical dimension within the deciduous denti-tion. As shown in Fig. 1.14, the patient’s perma-

nent anterior teeth and permanent first molarsare relatively unaffected by wear. However, thedeciduous canines and molars attest to occlusalsurface loss from erosion potentiated by attri-tion. On the upper teeth, the surfaces most af-fected are the occlusal and palatal slopes. Onthe lower teeth, it is the occlusal and buccalsurfaces that are most worn. When the clini-cian encounters this clinical presentation in themixed dentition, caution must be exercised be-fore concluding that the pattern of wear is theresult of bruxism. This 11-year-old patient gavea history of early childhood gastric reflux andongoing asthma with long-term medications,which reduced saliva protection against intrin-sic acids and those in frequently consumed softdrinks and other acidic beverages. Patients ofall ages may be affected by intrinsic acids, and60% of the population may experience refluxat some stage in their lives (ten Cate & Imfeld1996). However, longer term exposure to in-trinsic acids is required to result in signifi-cant toothwear. As conceptualised in Fig. 1.15,the most severe lesions on the deciduous teethare on surfaces least protected by saliva fromthe major glands. Intrinsic and extrinsic acidswould further affect certain parts of the den-tition and particular tooth surfaces more thanothers. Further investigation is warranted toidentify multifactorial aetiology. The presenta-tion of and reasons for toothwear in childrenand appropriate management approaches arefurther considered in Chapters 2 and 3.

TOOTHWEAR ANDDENTAL CARIES

It is rare for the clinician to encounter activedental caries in patients with worn dentitions.This is because erosion, attrition and abrasionare not caused by bacteria. In fact, the metabolicactivities of cariogenic organisms that convertsimple sugars to acids are inhibited by the lowpH found on the surfaces susceptible to den-tal erosion, as key enzymes in Streptococcus



(a)

(b) (c)

Figure 1.14 This 11-year-old male patient has (a) incisal attrition, chipping and mild thinning of enamel acrossthe anterior teeth. (b) The maxillary teeth show heavily worn surfaces on deciduous canine and molar teeth withnear exposures of the pulp. (c) The lower permanent canine and incisor teeth have erupted, but as yet wereunworn. Near exposures on the heavily worn lower deciduous molar teeth are evident. (From Young, 2001a, withpermission from the Australian Dental Journal.)

mutans cease to metabolise at pH values of 4.2or below at which they become increasinglyunviable (Meurman & ten Cate 1996). In thecase illustrated in Fig. 1.16, the astute clinicianwould have no problem discriminating buccalcervical lesions on the lower anterior teeth withundermined enamel edges as arrested cariesof dentine from shallow cervical erosions. This19-year-old female patient was a professionaldancer, who consumed fluoridated water in thefirst 12 years of her life and had no other ac-tive caries lesions. In her early teenage years,

the patient commenced binge eating of sugarysnacks between ballet rehearsals. This presum-ably caused the observed dental caries. How-ever, a few years subsequently, attacks of self-induced vomiting and high consumption ofsoft drinks increased the higher influence ofintrinsic and extrinsic acid consumption. Thischanged the nature of her oral pathology.

The distribution of both the lesions of ero-sion and caries (Fig. 1.17) can in part be ex-plained by loss of saliva protection from dehy-dration. Acids from sugars, produced by dental



Figure 1.15 Conceptualisation of the 11-year-old patient shown in Fig. 1.14. Mild attrition is present on hisincisors (green). Two deciduous canines and eight molar teeth are severely worn (orange). The two permanentlower molars show the amount of erosion (yellow) that occurred since age 6, when they erupted into his mouth.Mucous is secreted from the inner surfaces of the lips, cheeks, back of the palate, and sublingual glands. Seroussaliva flows from the parotid glands through ducts that open on the inner surface of the cheeks (taps). In thefloor of the mouth serous and mucous saliva are mixed from the submandibular ducts (taps) with mucous from thesublingual gland. (From Young, 2003a, with permission of Erosion Watch Pty Ltd.)

plaque bacteria at sites of caries, usually donot contribute to demineralisation on surfacessusceptible to dental erosion. Also, these sur-faces are normally protected by saliva. Reducedsaliva flow in anorexia nervosa and bulimia(Milosevic & Dawson 1996) placed this patient,in recent years, at risk of both gastric and di-etary acids that cause erosion but not dental

caries. Patients with poor oral hygiene are atgreater risk of developing dental caries and/orperiodontal disease. Most patients with moder-ate or severe toothwear, however, present withgood oral hygiene and low levels of plaque ac-cumulation. Dental erosion from intrinsic acidsinvolves the strongest acids with a pH as lowas 1, whilst soft drinks and fruit juices may

toothwear · 2013. 7. 23. · utilising the charted odontogram to assess patient risk 72 summary 73...

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