a comparative evaluation of the combined occluding …
TRANSCRIPT
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“A COMPARATIVE EVALUATION OF THE COMBINED OCCLUDING EFFECT
OF SODIUM FLUORIDE VARNISH AND ER:YAG LASER IRRADIATION ON
DENTINAL TUBULES-A CONFOCAL LASER SCANNING MICROSCOPE AND
SCANNING ELECTRON MICROSCOPE- AN IN VITRO STUDY.”
By
Dr. SAHIL R. KAWLE
Dissertation Submitted to the
Rajiv Gandhi University of Health Sciences, Karnataka, Bangalore
In partial fulfillment of the requirements for the degree of
MASTER OF DENTAL SURGERY
In
Conservative Dentistry and Endodontics
Under the guidance of
Dr. PRAHLAD A. SARAF, M.D.S.
DEPARTMENT OF CONSERVATIVE DENTISTRY AND ENDODONTICS
P.M.N.M. Dental College and Hospital, Bagalkot,
Karnataka-587101
2016- 2019
Scanned by CamScanner
Scanned by CamScanner
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LIST OF ABBREVIATIONS
ABBREVATIONS FULL NAME
CDH Cervical Dentine Hypersensitivity
CFFM Computerized Fluid Filtration Method
CLSM Confocal Laser Scanning Microscope
CO2 Carbon Dioxide Laser
CSPS Calcium Sodium PhosphoSilicate
oC Degree Celsius
DH Dentinal Hypersensitivity
DL Diode Laser
Er Cr:YSGG Erbium, Chromium doped Yttrium, Scandium, Gallium and
Garnet
Er:YAG Erbium doped Yettrium Aluminium Garnet
ESEM Environmental Scanning Electron Microscope
Fig. Figure
GaAlAs Galium Aluminium Arsenide
HAP Hydroxyapatite
He-Ne Helium Neon Laser
Hz Hertz
µm Micrometer
Min Minutes
Mm Millimeter
MJ Mega Joules
n-Hap Nano-Hydroxyapatite Agents
NaF
Sodium Fluoride
Nd:YAG Neodymium doped Yettrium Aluminium Garnet
% Percentage
P Probability Value
Sec. Seconds
SEM Scanning Electron Microscopy
SPSS
Statistical Package For Social Science
VAS Visual Analogue Scale
LIST OF TABLES
Table No. CONTENTS Page No. 1. Normality of tubules diameter of dentinal tubules scores by Kolmogorov
Smirnov test.
27
2. Normality of depth of penetration of die in dentinal tubules scores by
Kolmogorov Smirnov test.
27
3. Summary of tubules diameter scores in four study groups (A, B, C and D)
27
4. Comparison of four study groups (A, B, C and D) with respect to mean
tubules diameter scores by one way ANOVA
27
5. Pair wise comparisons of four study groups (A, B, C and D) with respect
to mean tubules diameter scores by Tukeys multiple posthoc procedures
28
6. Comparison of two study groups (E and F) with respect to mean depth of
penetration of die in dentinal tubules scores by independent t test
28
LIST OF GRAPHS
Sl.No. Contents Page no.
1 Comparison of four study groups (A,B,C and D) with respect
to mean of tubules diameter of dentinal tubules scores.
29
2 Comparison of two study groups (E and F) with respect to
mean depth of penetration of die in dentinal tubules scores
30
LIST OF FIGURES
S.No. Contents Plate No. 1. Teeth specimens for study 1
2. Tooth section of specimens 1
3. Armamentarium 2
4. Er:YAG Laser 2
5. Tooth Sectioning 3
6. Sodium Fluoride varnish Application 3
7. Rhodamine B dye Application 3
8. Er:YAG Laser Application 3
9. Scanning Electron Microscope 4
10. Confocal Laser Scanning Microscopy 4
11. SEM images 5
12. CLSM images 5
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ABSTRACT
“A COMPARATIVE EVALUATION OF THE COMBINED OCCLUDING EFFECT
OF POTASSIUM FLUORIDE VARNISH AND ER:YAG LASER IRRADIATION
ON DENTINAL TUBULES-A CONFOCAL LASER SCANNING MICROSCOPE
AND SCANNING ELECTRON MICROSCOPE- AN IN VITRO STUDY.”
BACKGROUND AND OBJECTIVE: Dentin hypersensitivity (DH) is one of the most
frequent problems causing patients. Various treatment modalities have been proposed for
dentin hypersensitivity, but to date, no single agent or form of treatment has been found
effective. The Er:YAG lasers have promising potential for the treatment of dentine
hypersensitivity. Lasers in combination with sodium fluoride varnish appear to show better
efficacy compared to either treatment modality alone. Thus the aim of this in vitro study was
to compare and evaluate the combined occluding effect of sodium fluoride varnish and
Er:YAG laser irradiation on dentinal tubules through scanning electron microscope and
confocal laser scanning microscopy.
MATERIAL AND METHOD: Forty five extracted maxillary premolar teeth were included
in this study. 3-mm-thick horizontal slice was prepared from the cemento-enamel junction of
each tooth using a slow-speed diamond saw. Each slice was transversely separated into two
halves as buccal and lingual 90 samples was obtained and these samples was randomly
divided into six equal groups. Groups A, B, C and D was used for the evaluation of tubule
occlusion with Scanning Electron Microscope (SEM). Groups E and F was separated for
dentin permeability with Confocal Laser Scanning Microscopy (CLSM).
RESULTS: Results of present study reveals that SEM analysis presented occlusion and
narrowing of dentinal tubules in all treatment groups, but more prominent occlusion was
observed in the combined treatment group. CLSM shown less dye penetration for combined
Er:YAG laser and sodium fluoride (NaF) varnish than alone treatment modality. Intergroup
comparisons regarding the tubule diameters and the number of the open dentinal tubules per
100 µm2 revealed statistically significant difference in favour of combined group ( p < 0.05).
The difference between single effects of Er:YAG laser and NaF in all parameters were found
statistically significant.
CONCLUSION: Within the limitation of this study of this in vitro study,it can be concluded
that, all the treatment modality for reducing dentinal hypersensitivity were effective for the
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occlusion and narrowing of dentinal tubules. The more prominent occlusion was observed in
the combined treatment of Er:YAG laser and sodium fluoride varnish on dentinal
hypersensitivity. Therefore, whether used alone or in combination of Er:YAG laser and
sodium fluoride varnish, Er:YAG laser irradiation is effective for the treatment of dentinal
hypersensitivity.
KEYWORDS: Dentin hypersensitivity, Confocal Laser Scanning Microscopy, Er:YAG
laser, Scanning Electron Microscope, Sodium Fluoride varnish.
Introduction
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INTRODUCTION
Dentine Hypersensitivity (DH) is a common occurrence and a concern among
patients. Currently, DH represents a challenging problem to the dental profession, in
view of a substantial increase in the population during the late 20th century.
According to the ‘‘hydrodynamic theory’’ movements of fluid within exposed
dentinal tubules are responsible for the stimulation of pulpal mechano receptors. It is
characterized by short, sharp pain arising from exposed dentin in response to stimuli,
typically thermal, evaporative, tactile, osmotic, or chemical and which cannot be
described to any other dental defect or disease. Many factors, such as abrasion,
erosion, attrition and gingival recession following scaling and root planing (SRP).
Some other factors, including age, sex, occlusion incompatibility, oral pH, local
bacterial plaque and the level of the patient’s oral health can also seriously affect
dentinal hypersensitivity1.
Currently there are at least two recognized mechanisms of action of
desensitizing agents: (1) blocking fluid movement by occluding tubules and (2)
blocking pulpal nerve activity by altering the excitability of the sensory nerves. A
wide variety of chemical and physical agents have been used for the treatment of the
dentin hypersensitivity such as anti-inflammatory agents (corticosteroids); protein
precipitants (formaldehyde, silver nitrate, strontium chloride hexahydrate); tubule
occluding agents (calcium hydroxide, potassium nitrate, sodium fluoride); and tubule
sealants (resins and adhesives).2
There are several methods used for the treatment of DH. These methods
include instructions for proper brushing, dietary advice, occlusal adjustment, use of
desensitizing products, irradiation of low-power or high-power lasers, the use of
adhesive systems and adhesive restorations. A product containing the combination of
an aqueous solution of 35% hydroxyethyl methacrylate and 5% glutaraldehyde
(Gluma desensitizer, Heraeus Kulzer GmbH) is considered to be an efficient
desensitizing agent. Dentinal tubules are inherently blocked by the glutaraldehyde and
this counteracts the hydrodynamic mechanism that gives rise to DH. Nano-
hydroxyapatite (n-Hap) agents, generally considered among the most biocompatible
and bioactive materials available in dentistry, which has the potential to repair dental
enamel are effective in occluding dentinal tubules are also used in treatment of DH.3
Introduction
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Calcium sodium phosphosilicate, known by the trade name NovaMin, contains
calcium, sodium, phosphate and silica and is initially used for bone regeneration.
NovaMin has also been used as a desensitizing agent for occluding dentin tubules.
NovaMin-containing agents, including NUPRO Sensodyne Prophylaxis Paste with
NovaMin (with and without fluoride (NPP)), which is used to reduce DH following
periodontal dental treatment, such as scaling-root planning.4
Synthetic hydroxyapatite (HAP) has been described as a biocompatible and
biomimetic compound which is able to reduce hypersensitivity and to potentially
enhance remineralization. Recently, toothpastes containing HAP have proved
clinically effective for treatment of DH. A particular crystalline zinc substituted
hydroxyapatite used for the treatment of DH was analyzed with various
physicochemical methods. Because of its particle size of about 200–400 nm, these
Hydroxyapatite crystallites are well suited to occlude open dentin tubuli. For testing
dentin permeability, different in vitro methods have been described, based either on
measuring the diffusion or the perfusion of marker substances through dentin before
and after material application, simulating a one-time use of a product or compound.
Hydroxyapatite as such interacts with saliva proteins forming the enamel pellicle due
to its high polarity. Many different salivary proteins can bind to the enamel surface,
e.g. proline-rich proteins, cystatins, statherins, histatins and others. Two mechanisms
of protein adsorption are reasonable, a direct mineral-protein interaction and a
protein-protein interaction.5
The Colgate Sensitive Pro-Relief daily paste which contains a Pro-Argin™
formulae (containing 8% arginine and calcium carbonate as well as 1450 ppm sodium
monofluorophosphate) and the Sensodyne Rapid Relief (containing 8% strontium
acetate and 1040 ppm sodium fluoride) as also used in the treatment of DH. Arginine
is a relatively recent addition to the dentine tubular occlusion technologies,whereas
strontium salts have been used in dentifrices for more than half a century. Clinical
studies show 8% arginine-based dentifrices reduce DH immediately and following 3
day and 8 week applications compared to control, 2% potassium nitrate or citrate and
1450 ppm sodium monofluorophosphate fluoride based dentifrices. Similarly, 8%
strontium based dentifrice in silica base reduces DH significantly compared to 1450
ppm sodium fluoride in silica base and an 8% arginine and 1450 ppm sodium
monofluorophosphate.6
Introduction
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An early in situ randomised control trial using dentine samples treated with
8% strontium acetate based dentifrice, showed a dentine surface deposit resistant to
water rinsing. In addition, 8% strontium acetate based dentifrices have shown
significant dentine tubular occlusion compared to 8% arginine, 5% potassium nitrate,
strontium chloride, fluoride,
1% and 3% polysaccharide and 1% phosphate salt based dentifrices, chlorhexidine
and water in vitro following acidic challenge. Although 8% arginine-based dentifrices
have demonstrated dentine tubular occlusion and resistance to an acid challenge
invitro there is some debate as to the robustness of the occlusion when faced with an
acidic challenge.6
Calcium sodium phosphosilicate (CSPS) is an ingredient found in a number of
professional use and over-the-counter dental products designed to provide relief from
DH. CSPS is a bioactive glass (CaO-Na2O-P2O5-SiO2) and was originally developed
as bone repair material in the early 1970s.CSPS has been reported to form a direct
bond with calcified tissue following exposure to an aqueous environment. Once in an
aqueous environment CSPS has been reported to undergo a series of chemical
reactions that result in an increase of the local pH to approximately 9. This creates an
environment suitable for silica release, formation of a porous silica gel surface and the
formation of calcium apatite.7
A reservoir of calcium and phosphate is formed beneath the silica gel and
these ions are released into the aqueous environment through the porous surface.
CSPS incorporated in dentifrice formulations has been reported to physically occlude
dentine tubules, increase dentine mineralization and provide relief from the pain of
DH. In vitro, in situ and clinical efficacy studies have demonstrated significant levels
of dentine occlusion and relief from dentine hypersensitivity, following treatment
with CSPS containing dentifrices.7
Sodium fluoride gel (NaF), which belongs to the tubule-occluding agents
family is the most commonly used agent by clinicians. This agent’s primary
mechanism relies on the mechanical occlusion that is accomplished by precipitation
of insoluble calcium fluoride crystals within the tubules without adhesion and thus
this agent cannot resist the stresses of the oral environment and degrades over time.8
In recent years new developing technical modalities lasers and topical ozone
gas have been proposed for the treatment of DH. Laser systems such as He-Ne, diode,
Co2, Nd:YAG and erbium lasers (Er,Cr:YSGG,Er:YAG) have been used as potential
Introduction
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treatment alternatives. Among these laser systems, Er:YAG laser has drawn attention.
Er:YAG laser with 2.94 µm wavelength is highly absorbed in water and less in
hydroxyapatite and is considered to be one of the low-risk lasers without producing
thermal effects. The mechanism behind the laser’s effect on dentine hypersensitivity is
thought to be laser-induced occlusion, narrowing of dentinal tubules or direct nerve
analgesia. The efficacy of laser in dentinal hypersensitivity therapy can be related to
both high power, causing coagulation of fluids contained in the dentinal tubules
having a melting effect with crystallization of dentine inorganic component, and the
direct action of laser to low power on nerve transmission with suppression of the pulp
nociceptive nervous fibers, blocking diffusion of pain to the central nervous system.9
The Er:YAG laser appears to be suitable for successful reduction of dentine
hypersensitivity. Its thermomechanical ablation mechanism and the high absorption of
its wavelength by water may lead to a decrease in dentinal fluid movement by
evaporating the superficial layers of dentinal fluid. To increase the effectiveness of
dentin hypersensitivity treatment researchers postulated combination treatments, such
as lasers and chemical agents. Combination of Er:YAG laser and 5% sodium fluoride
(NaF) varnish seemed to show efficacy when compared with either treatment alone, in
treating dentine hypersensitivity.10
The erbium laser family, including the Er;Cr:YSGG laser, is well-known for
its dental hard tissue ablation ability. This phenomenon is mostly attributed to high
absorption in the bonded water content of the crystallized structure of the tooth, which
leads to abrupt expansion and subsequently explosion of dental hard tissue.10
It has been indicated in the literature that when Er:YAG laser was applied with
lower than the ablation thresholds of dental hard tissues, it was supposed that Er:YAG
laser evaporated the superficial layers of the dentinal fluid and produced a decrease of
the rate flow thereby reducing sensitivity a decrease of the rate flow thereby reducing
sensitivity.10
Aims And Objective
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AIMS AND OBJECTIVE
The aim of this in vitro study was to compare and evaluate the combined occluding
effect of sodium fluoride varnish and Er:YAG laser irradiation on dentinal tubules
through scanning electron microscope and confocal laser scanning microscopy.
Review Of Literature
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REVIEW OF LITERATURE
An in vitro study was conducted by Ogul L et al, to evaluate the in vitro
effects of Er:YAG laser and an in-office desensitizing paste alone or in combination
by using scanning electron microscopic (SEM) analysis. Forty dentine specimens
obtained from freshly extracted impacted third molars were included and divided into
four groups. Group I served as the control, whereas Group II, Group III and Group IV
recieved Er:YAG laser, a desensitizing paste (DP) containing 8% arginine and
calcium carbonate and DP + Er:YAG laser in combination, respectively, evaluated
under SEM which presented occlusion and narrowing of dentinal tubules in all
treatment groups, but more prominent occlusion was observed in the combined
treatment group. Intergroup comparisons regarding the tubule diameters and the
number of the open dentinal tubules per 100 µm2 revealed statistically significant
difference in favor of combined group. The difference between single effects of
Er:YAG and DP in all parameters were found statistically non significant.
An in vitro study was conducted by Gholam Ali Gholami et al is aimed to
evaluate the occluding effects of Er;Cr:YSGG, Nd:YAG , CO2 and 810-nm diode
lasers on dentinal tubules. Fifteen human third molars were collected and ground-
sectioned vertically on the buccal and lingual surfaces to yield two dentin disks of 2-
mm thickness. Then, four sites for laser irradiation and one control site were marked
in the cervical areas of the dentin disks. Before laser application, specimens were
exposed to a 14% EDTA solution to expose dentinal tubules and were then evaluated
by scanning electron microscopy (SEM). The tubules’ entrance diameters were
determined by ‘‘scale-bar’’ software, which is specifically designed for SEM. The
mean diameters for the tubules were then estimated for each site. The mean dentinal
tubule entrance diameters for Er;Cr:YSGG, 810-nm diode, CO2 and Nd:YAG, were
1.73, 3.27, 2.10 and 1.64 microns, respectively, compared with 3.52 microns before
laser irradiation. However, tubular diameter reduction in all laser groups was found to
be statistically significant and thus concluded Nd: YAG, Er; Cr: YSGG, and CO2
lasers, through their ability to melt peritubular dentin, can occlude dentinal tubules
partially or totally and therefore reduce patients’ hypersensitivity symptoms. The 810-
Review Of Literature
[Type text] Page 7
nm diode laser sealed tubules to a far lesser degree, with negligible effects on
desensitization.
An in vivo study was conducted by Reza Birang et al, to evaluate the
comparative effect of Nd:YAG laser and Er:YAG laser on human teeth
desensitization. A group of nine patients with a total of 63 chronic hypersensitive
teeth were selected and were randomly allocated into three groups. Group 1, Nd:YAG
laser, group 2 Er:YAG laser and group 3 serves as control group without any
treatment. Assessment of pain was performed by a visual analogue scale (VAS) after
stimulation of sensitive tooth by using the sharp tip of an explorer. This test was
performed before treatment, immediately after that and at 1, 3 and 6-month intervals
after treatment by one blinded examiner. Analysis of VAS score between the three
groups at the time of treatment did not show any significant difference. However, by
using repeated-measurement analysis of variance test, significant differences were
seen in the three groups between before-treatment VAS score and after treatment.
This statistically significant difference in the control group demonstrated a placebo
effect. However, the effect of using Nd:YAG and Er:YAG lasers was stronger than
this placebo effect, so that after removing the effect of the placebo, differences
immediately after, 1,3 and 6 months post treatment between all three groups still were
statistically highly significant. Compared to the Er:YAG laser group, using Nd:YAG
laser resulted in a significant reduction of VAS score at each follow-up examination.
Although using Nd:YAG and Er: YAG laser in desensitization of hypersensitive teeth
showed a placebo effect limited to a short time, results of this study demonstrated that
both of these lasers have an acceptable therapeutic effect. The observed effects
seemed to last for at least 6 months. It was concluded that Nd:YAG laser is more
effective than Er:YAG laser in reduction of patients’ pain.
An in vitro study was conducted by Gokser Cakar et al, to evaluate the
occluding effect of erbium:yttrium-aluminum-garnet (Er:YAG) and carbon dioxide
(CO2) lasers as mono therapy and in combination with topical fluoride gel on human
dentinal tubules by scanning electron microscopic (SEM) examination. Thirty-six
dentine specimens with exposed dentinal tubule orifices were included in this study.
The samples were divided into six groups. Group A served as controls, group B was
treated with 2% sodium fluoride (NaF) gel alone, groups C and D were irradiated with
Review Of Literature
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Er:YAG and CO2 lasers, respectively and groups E and F received NaF gel plus
Er:YAG and CO2 laser irradiation, respectively. Under SEM analysis, numerous
exposed, normally-structured dentinal tubule orifices were seen in the control group.
Some narrowing of the exposed tubule orifices was seen in group B. A melted,
irregular surface structure with small peaks was observed in group C. The surface of
group D also had a melted appearance, but a fibrillar deformation. However, the
surface morphologies seen were remarkably different in groups E and F. While the
tubule orifices were obviously occluded but depressed into craters in group E, the
surface structure of group F primarily showed a smooth appearance. In terms of
numbers and diameters of open dentinal tubules, there was no significant difference
between the laser-alone and combination groups, whereas the difference was found to
be significant when the control and NaF groups were compared with each other and
the remaining laser-alone or combination groups. The dentinal tubules in all laser
groups were occluded after laser irradiation, but more marked occlusions were
observed when laser and NaF gel were combined.
An in vitro study was conducted by Hare Gursoy et al, to evaluate the
occluding effect of topical gaseous ozone application and Er:YAG laser on human
dentine tubules by scanning electron microscopic (SEM) analysis. Twenty-four
dentine specimens were divided into three groups. Group I, including specimens
treated only with citric acid, served as the control. Group II was treated with Er:YAG
and Group III received only topical gaseous ozone application. Diameters and the
number of open dentinal tubules per 100 µm2 were counted from SEM
photomigrophraphs at 2000 magnification. In terms of diameters and numbers of open
dentinal tubules per 100 µm2, both treatment modalities presented significant
occlusion. The mean values of the diameters and the number of open dentinal tubules
per 100 µm2 were observed in Group I, Group II, and Group III, in decreasing order.
Significant differences were found among the groups in favor of the topical gaseous
ozone applied group and concluded that the dentine tubules in both treatment groups
were occluded, however more marked occlusion were seen in ozone treated group.
An in vitro study was conducted by Wan Hong Lan et al, to evaluate the
combined occluding effect of sodium fluoride varnish and Nd:YAG laser irradiadition
on human dentinal tubules. Thirty-six dentin specimens with exposed dentinal tubules
Review Of Literature
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orifices were used in this study.The samples were randomly divided into four groups.
Group A, B and C were varnished by sodium fluoride,where as group D serves as
control.Then group C was lased by Nd:YAG laser by light painting. Three hours
later,group B and C were brushed by an electrical toothbrush for 30 min. Under SEM
observation,the control group shows numerous exposed dentinal tubule orifices and
the sodium fluoride varnished specimens showed closure of exposed dentinal tubule
orifices. After electrical tooth brushing, most of the sodium fluoride varnished was
brushed away, except in the specimen that were irradiated by Nd:YAG laser. Over
90% of the dentinal tubule orifices were occluded by sodium fluoride varnished
combined with Nd:YAG laser irradiation.
An in vivo study was conducted by Schwarz F et al, to evaluate and compare
the desensitizing effects of an Er:YAG laser and Dentin ProtectorA on cervically
exposed hypersensitive dentine. A group of 30 patients showing a total of 104
contralateral pairs of hypersensitive and caries-free teeth was selected and randomly
allocated in a split mouth design to either (1) Er:YAG laser or (2) the application of
Dentin Protector A where at one pair served as an untreated control in each patient.
The degree of sensitivity to a thermal stimulus was determined qualitatively with an
evaporative stimulus defined as a three second air blast at a distance of 2 mm from
each site to be tested. A qualitative registration of the degree of discomfort was
determined according to an arbitrary pain scale in 4 degrees. Recordings were
assessed before treatment, immediately after, 1 week, 2 and 6 months after treatment
by 1 blinded examiner. Both treatment forms resulted in significant improvements of
discomfort immediately after and 1 week post treatment. After 2 months, the
discomfort in the Dentin Protector A group increased up to 65% of the baseline score
and even up to 90% after 6 months, whereas the effect of the laser remained at the
same level that was achieved immediately after treatment. The differences
immediately after, 1 week, 2 and 6 months post treatment between both groups were
significant. Compared to the untreated control group, both treatment forms resulted in
a significant reduction of discomfort at each follow-up examination.
An in vivo study was conducted by Sebnem Dirikan Ipci et al, to evaluate and
compare the efficacy of Co2 and Er:YAG lasers alone and in combination with topical
sodium fluoride (NaF) in the management of dentine hypersensitivity. A group of 50
Review Of Literature
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patients presenting with a total of 420 hypersensitive teeth were randomly allocated
into five groups. Group 1 was treated with 2% NaF, groups 2 and 3 were lased by a
Co2 or Er:YAG laser and groups 4 and 5 received NaF plus the Co2 and the Er:YAG
laser, respectively. The degree of thermal sensitivity was determined with an
evaporative stimulus consisting of a 1-sec air blast at a distance of 2 mm from each
site tested. Quantification of the degree of discomfort was determined according to a
four-point pain scale before treatment and 1 week, 1 months, and 6 months after
treatment. All treatment forms resulted in significant improvement of discomfort. At 1
week, 1 month, and 6 month, cold air blast scores were significantly reduced
compared to baseline scores, except for the NaF group. In the NaF group, there was a
statistically significant increase in mean degree of discomfort at 6 mo compared with
1 week and 1 month. Comparison of the other treatment regimens revealed that cold
air blast scores were significantly lower for the other four treatments than for NaF gel
alone. No superiority was found for desensitization among the Co2, Er:YAG, Co2,
NaF and Er:YAG,NaF groups and thus concluded that both the Co2 and Er:YAG
lasers have promising potential for the treatment of dentine hypersensitivity. Lasers in
combination with NaF gel appear to show better efficacy compared to either treatment
modality alone.
An in vivo study was conducted by Azher Banu Pathan et al, to evaluate the
effectiveness of three desensitizing agents on dentinal tubule obliteration and their
durability in use on the dentinal tubules. Sixty specimens were obtained from 30
extracted sound human maxillary first premolars. Each tooth was mesiodistally
sectioned to obtain 30 buccal and 30 lingual surfaces and enamel was removed in
order to simulate hypersensitive dentin. Specimens were divided into four groups with
15 specimens each. Group 1 samples were immersed in artificial saliva, Group 2
samples were coated with Vivasens, Group 3 samples were coated with VOCO
Admira Protect and Group 4 samples were coated with Neo Active Apatite
suspension. These specimens were examined under scanning electron microscope
(SEM) to find out the occluding ability of the respective products. The specimens
were brushed to find out their durability for 1 week and 1 month and were examined
under SEM. The results showed that Group 1 differed significantly from the Vivasens,
Admira, and Neo Active Apatite groups at 5% level of significance. The Vivasens
Review Of Literature
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group differed significantly from the Admira and Neo Active Apatite group.The
Ormocer-based Admira Protect showed the best results.
An in vitro study was conducted by Samet Tosun et al, to evaluate the dentinal
tubule occlusion potential and penetration of Clinpro White Varnish (5% sodium
fluoride tricalcium phosphate) in the presence or absence of Nd: YAG laser. Seventy-
five dentin samples collected from 38 freshly extracted human molars were randomly
divided into five groups (n 15). Groups A, B, D and E were varnished with Clinpro,
whereas group C (no treatment) served as the control group. Groups B and E were
further irradiated with Nd:YAG laser. All study groups were subjected to pH cycling.
Groups A, B and C were evaluated for tubule occlusion using scanning electron
microscopy. Groups D and E were evaluated for penetration with confocal laser
scanning microscopy (SEM). Tubular occlusion of groups A and B were significantly
greater than group C. Tubular occlusion of group B were significantly greater than
group A. Penetration depth for group D was significantly greater than group E. Laser
application improved the tubular occlusion capacity of Clinpro,on the contrary, laser
reduced the penetration of Clinpro.
An in vivo study was conducted by Ozlem K et al,to determine and compare
the efficiency of the glutaraldehyde-containing agent (GCA), Nd:YAG, Er,Cr:YSGG
lasers and the combination of them on the dentin hypersensitivity (DH) treatment.
This study was performed with the participation of 17 healthy adult patients having
100 teeth with DH; the patients were randomly divided into five groups according to
the treatment protocol: (1) application of GCA on sensitive teeth, (2) Nd:YAG laser
irradiation on sensitive teeth, (3) application of GCA on sensitive teeth and then
Nd:YAG laser irradiation, (4) Er,Cr:YSGG laser irradiation on sensitive teeth, (5)
application of GCA on sensitive teeth and then Er,Cr:YSGG laser irradiation.
Sensitivity levels were assessed by the Yeaple probe on the buccal surfaces of the
teeth at a force setting of 10 g. Measurements were performed for 30 min, after 7, 90,
and 180 days of the therapy to assess the effects of desensitization. After sessions, DH
was significantly reduced in all groups at each measurement point. The Er,Cr:YSGG
laser with or without GCA application were the most effective ones in DH treatment.
Comparison of the treatment regimens demonstrated that the scores achieved with the
Yeaple probe were not significantly higher for the Nd:YAG laser groups than the
Review Of Literature
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GCA alone group.This clinical study shows that the Er,Cr:YSGG laser have
promising potential for the treatment of DH.
An in vivo study was conducted by Sevda Kurt et al, to evaluate and compare
the efficacy of Er:YAG laser, Nd:YAG laser, PrevDent nano-hydroxyapatite
toothpaste plus Repairing Serum Kit (PNH), and NUPRO Sensodyne Prophylaxis
Paste with NovaMin (NPP) on dentin permeability reduction. Forty dentin discs
obtained from bovine incisors were divided into four study groups: Er:YAG laser-
treated Nd:YAG laser-treated PNH-treated and NPP-treated groups. The quantitative
changes in permeability of each dentin disc were measured using a computerized fluid
filtration method (CFFM) before and after desensitizer treatments. The dentin
surfaces and tubules were also morphologically detected by scanning electron
microscopy (SEM). In all groups, dentin permeability was significantly reduced after
the desensitizer and laser treatments. Among the groups, significant difference was
observed in only when comparing the Er:YAG laser and NPP-treated groups. SEM
analysis revealed physical changes in the dentin surface in all groups. All tested
desensitizers and laser treatments exhibited reduced dentin permeability. Also, surface
changes, such as complete or partial occlusion or shrinkage of dentin tubules, were
observed in all groups. Although the laser groups performed best, the PNH protocol
can be considered as an alternative therapeutic product.
An in vivo study was conducted by Romeo Umberto et al, to compared the
effectiveness of GaAlAs diode laser alone and with topical sodium fluoride gel (NaF).
The study was conducted on 10 patients and 115 teeth with dentinal hypersensitivity
assessed by air and tactile stimuli measured by Numeric Rating Scale (NRS). Teeth
were randomly divided into G1 treated by 1.25% NaF; G2 lased with diode laser
fluence G3 received NaF gel plus laser G2. NRS was checked at each control.
Significant pain reduction was showed.The NRS reduction percentages were
calculated, and there was a concrete decrease of DH above all in G3 than G2 and G1
and thus concluded that diode laser is a useful device for DH treatment if used alone
and mainly if used with NaF gel.
An in vivo study was conducted by Sandra Ribeiro Cunha et al, to evaluate the
association between Nd:YAG laser and two desensitizing dentifrices containing 15%
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[Type text] Page 13
NovaMin or 8% arginine, as potential treatments for dentin hypersensitivity (DH).
DH was simulated by EDTA application for 2 min. Specimens were then analyzed
with an environmental scanning electron microscope (ESEM) to ensure open dentin
tubules (ODT), counted by using ImageJ software. Specimens were randomized into
eight groups (n = 10): Laser (L), Laser+ Photoabsorber (LP), Arginine (A),
Arginine+Laser (AL), Arginine+Laser+Photoabsorber (ALP), NovaMin (N),
NovaMin+Laser (NL), and NovaMin+Laser+Photoabsorber (NLP). Laser irradiation
was performed with 1 W, 4 irradiations of 10 second each, with 10 second intervals
between them. After treatment, specimens were again analyzed by ESEM and
submitted to erosive/abrasive cycling for 5 days. A final ESEM analysis was
performed. None of the associations tested presented better tubule occlusion than
NovaMin by itself. Arginine was the only treatment that presented improved tubule
occlusion when associated with Nd:YAG laser.
An in vivo study was conducted by I.DURAN et al, to compare the long-term
effectiveness of five desensitizing products on 25 male and 27 female patients (total
52) aged 21–67 years (mean 36 ± 7 years) suffering from cervical dentine sensitivity.
All subjects were seen by the same examiner (ID) who was blinded to the applied
treatment for 3-month clinical study. Patients were asked to record their overall
sensitivity by marking a point on a 10 cm Visual Analogue Scale (VAS). 277
sensitive teeth were treated by one of the five desensitizing products, of A paired
(split mouth) study design was used and selection of quadrants was randomized. At
the post-treatment and at 10 days and 3 months periods, sensitivity measurements
were recorded by the same investigator (ID). Statistical analysis showed that all of the
VAS scores at post-treatment evaluation points were significantly decreased
compared with baseline data. There was a significant reduction in mean sensitivity
scores in the Protect Liner F and the Health-Dent Desensitizer groups when compared
with Fluoline varnish at the 10-day time point. At 3 months, the Protect Liner F group
continued to show a significantly reduced sensitivity level when compared with
Health-Dent Desensitizer, Single Bond, Fluoline and Gluma Desensitizer. The present
study demonstrated that although at the end of 3-month evaluation period all
desensitizers showed lower VAS sensitivity values compared with baseline, there
were differences in the level of reduction of cervical dentine sensitivity.
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An in vitro study was conducted by Eleftherios Terry R. Farmakis et al, to
evaluated the efficacy of bioglass and Nd:YAG laser irradiation on dentinal tubuli
orifice occlusion (DOO) by comparing samples examined under environmental
scanning electron microscope (ESEM) after applying each desensitizing approach
separately and in combination. Forty-eight human molars were collected, randomly
organized in 4 equal groups and had their cervical dentin exposed. Additionally, in
half of the specimens of each experimental group, the smear layer was removed
(subgroups A1, B1, C1, and D1). Group A received NovaMin paste treatment for 5
minutes (NM) to the experimental surface. Group B received Nd:YAG laser
irradiation. Group C received NM followed by laser. Group D was treated with laser
followed by NM. All specimens were stored for 24 hours and evaluated for DOO
under ESEM by 4 blinded observers.The presence of a smear layer significantly
contributed to DOO regardless of the treatment modality. Compared with group A, all
other treatments delivered significantly more occluded dentin orifices. A layer
formation was observed in subgroups C2 and D2. Under these experimental
conditions, a smear layer was essential for successful DOO. Laser irradiation alone
and combined with NovaMin proved superior to NovaMin alone on DOO. This
combined approach has the potential to improve the outcome of treatment for cervical
dentin hypersensitivity. The biological significance of this newly formed layer needs
to be elucidated.
An in vivo study was conducted by Felice Femiano et al. This study compares
sensitivity reduction after dental restoration with and without prior diode laser (DL)
irradiation for cervical dentine hypersensitivity (CDH) from non-carious cervical
lesions (NCCLs) unresponsive to desensitizing agents. Eighty-eight teeth of 28
subjects, with CDH from NCCL were included in this study. NCCLs of each oral
quadrant were randomized in two groups (study group (SG)) to estimate the
sensitivity reduction after dental restoration (SG-1) compared with the DL irradiation
used prior to restoration placement (SG-2). The subjects were asked to rate the
sensitivity experienced during air stimulation using a visual analog scale before
(baseline), immediately after and at 6 and 12 months from restoration. The outcomes
showed a significant reduction of discomfort compared to baseline for NCCLs of SG-
2 with the decrease of 78.5, 78.9 and 78.1 % immediately and at 6 and 12 months
after restoration, respectively; in comparison with the decrease of 70.1, 67, and 65.3
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[Type text] Page 15
% for NCCLs of SG-1 immediately and at 6 and 12 months after restoration,
respectively; and compared to baseline. The DL irradiation prior to dental restoration
can further improve the painful symptomatology of CDH from NCCL unresponsive to
desensitizing agents.
An in vitro study was conducted by Po-Jen Hsu et al, to evaluate the combined
occluding effects of fluoride-containing dentin desensitizer and neodymium:yttrium
aluminum garnet (Nd-YAG) laser irradiation on human dentinal tubules. All six of the
groups of dentin samples (A–F) included in this study received applications of
fluoride-containing dentin desensitizer Groups A and B served as controls, Groups C
and D were treated with 0.5 M vitamin C solution, whereas groups E and F underwent
brushing with an electric toothbrush, Groups B, D, and F received Nd-YAG laser
irradiation, to allow observations of the occluding effects on the dentinal tubules
before and after Nd-YAG laser irradiation. Scanning electron microscopy (SEM)
revealed that the fluoridated dentinal tubule-occluding agent (FDTOA) formed a fine
crystalline deposit on the dentin surface. After soaking in 0.5 M vitamin C solution
for three hours, the crystalline deposit of the FDTOA was completely dissolved.
Furthermore, brushing of the teeth 3,600 times removed most of the occluding agent.
When the application of FDTOA was combined with Nd-YAG laser irradiation, the
dentin melted and then recrystallized. The occluding agent was thus ‘burned into’ the
dentinal tubules, and could neither be dissolved by vitamin C solution nor removed by
brushing. concluded that the FDTOA combined with Nd-YAG laser irradiation burns
the occluding agent into the dentinal tubules, thereby resisting the effects of an acidic
diet and brushing and increasing the duration of the desensitizing effect.
An in vitro study was conducted by T. Pamir et al, to evaluate the efficacy of
three desensitizing agents vs. placebo. One hundred and six hypersensitive teeth of 26
patients were included in this study, and the baseline hypersensitivity level of all teeth
was established as ‘moderate’ by using Visual Analogue Scale (VAS). The teeth were
divided into four groups: to the first group 5% potassium nitrate bio-adhesive gel, to
the second 2% sodium fluoride bio-adhesive gel and to the third one step adhesive
system Prompt L-Pop were applied as desensitizing agents. Group 4 was the control
group in which a desensitizer-free bio-adhesive gel was used as placebo. Post
treatment and eighth week control measurements were recorded on VAS. It was
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observed that the efficacy of three desensitizing agents did not differ from each other
and except for placebo all reduced moderate dentin hypersensitivity effectively. 5%
potassium nitrate, 2% sodium fluoride bio-adhesive gels and one step bonding agent
Prompt L-Pop were effective in reducing moderate dentine hypersensitivity.
An in vitro study was conducted by S. A. M. Corona et al, to evaluate in vivo
the use of low-level galium–aluminium– arsenide (GaAlAs) (BDP 600) laser and
sodium fluoride varnish (Duraphat) in the treatment of cervical dentine
hypersensitivity. Twelve patients, with at least two sensitive teeth were selected. A
total of 60 teeth were included in the trial. Prior to desensitizing treatment, dentine
hypersensitivity was assessed by a thermal stimulus and patients’ response to the
examination was considered to be a control. The GaAlAs laser was irradiated on
contact mode and fluoride varnish was applied at cervical region. The efficiency of
the treatments was assessed at three examination periods: immediately after first
application, 15 and 30 days after the first application. The degree of sensitivity was
determined following predefined criteria. Data was submitted to analysis and no
statistically significant difference was observed between fluoride varnish and laser.
Considering the treatments separately, there was no significant difference for the
fluoride varnish at the three examination periods and for laser therapy, significant
difference was found solely between the values obtained before the treatment and 30
days after the first application. It may be concluded that both treatments may be
effective in decreasing cervical dentinal hypersensitivity. Moreover, the low-level
GaAlAs laser showed improved results for treating teeth with higher degree of
sensitivity.
An in vitro study was conducted by N. Gautham Kumar et al, to evaluate
clinically and under scanning electron microscopy (SEM) the efficacy of Nd:YAG
laser irradiation alone and in combination with 5% sodium fluoride varnish in the
management of dentin hypersensitivity. The study was conducted on 40 patients
divided into four groups who had at least one tooth of Grade III mobility with
clinically elicitable dentin hypersensitivity. Following the pretreatment assessment of
hypersensitivity using the visual analog scale (VAS) and cold air blast test, the
selected tooth in all the groups received 1% citric acid treatment for 1 minute. Group
1 patients received no further treatment; group 2, 3, and 4 patients received additional
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treatment with 5% sodium fluoride varnish, Nd:YAG laser for 2 minutes and a
combination of 5% sodium fluoride varnish and Nd:YAG laser, respectively. Two
hours following treatment, hypersensitivity was again assessed and the teeth were
extracted, sectioned and scanned using scanning electron microscopy (SEM) The
mean VAS score in group 1 showed a 27% increase from baseline, but groups 2, 3,
and 4 showed a decrease of 33%, 44% and 62%, respectively. The mean cold air blast
score showed a 22% increase in group 1, but values decreased by 43%, 50%, and 83%
in groups 2, 3, and 4, respectively. The number of patent tubules also progressively
decreased from group 1 through group 4. The combination of Nd:YAG laser and 5%
sodium fluoride varnish seems to show an impressive efficacy, when compared to
either treatment alone, in treating dentin hypersensitivity. The SEM findings seem to
relate to the clinical findings in that reduction in number/patency of tubules was
associated with improvement in treatment efficacy
An in vitro study was conducted by Anely Oliveira Lopes et al, to assess
different protocols for the treatment of dentin hypersensitivity with low-power laser
(with different doses), high-power laser and a desensitizing agent, for a period of 12
and 18 months. The lesions from 32 patients (117 lesions), were divided into nine
groups (n = 13): G1: Gluma Desensitizer, G2: low-power laser with low dose, G3:
low-power laser with high dose, G4: low-power laser with low dose + Gluma
Desensitizer, G5: low-power laser with high dose + Gluma Desensitizer, G6:
Nd:YAG laser, G7: Nd:YAG laser + Gluma Desensitizer, G8: low-power laser with
low dose + Nd:YAG laser, and G9: low-power laser with high dose + Nd:YAG laser.
The level of sensitivity of each volunteer was assessed by visual analog scale of pain
(VAS) with the aid of air from the triple syringe and exploration probe, 12 and 18
months after treatment. All analysis were performed separately for air and probe
stimulus, all treatments were effective in reducing dentinal hypersensitivity and the
results were considered not statistically different from those at 12 months and 18
months.
An in vitro study was conducted by Zahi badran et al, to obliterate the exposed
dentinal tubules by introduction of laser desensitization was introduced as an
alternative efficient tool for the immediate treatment of tooth hypersensitivity. Nine
freshly extracted single-rooted teeth were immersed for 30 min in a sodium
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[Type text] Page 18
hypochlorite solution (NaOCl 3%). The teeth were then thoroughly brushed until
organic debris had been completely eliminated. The specimens were then left for 24 h
in saline buffer. On each buccal side of the root of the included teeth, two deep
dentinal cavities were prepared using a diamond bur mounted on a high-speed
handpiece. The teeth were then embedded in putty in small petri dishes. All cavities
were then acid-etched with 37% phosphoric acid. After 20 s, the phosphoric acid was
removed by rinsing with saline buffer for 40 s. Immediately after rinsing, an Er:YAG
laser device was used to irradiate one test cavity in each tooth for 30, 60 and 120 s.
They were then viewed with a scanning electron microscope at 20 kV under high-
vacuum conditions. None of the irradiated samples showed signs of thermal damage
(cracking, melting or carbonization) to the irradiated dentin.
An in vivo study was conducted by Anisha Merh et al, to evaluate the
immediate efficacy of diode laser versus desensitizing paste containing 8% arginine
and calcium carbonate in the treatment of dentine hypersensitivity. Fifty patients with
complain of tooth hypersensitivity were randomly selected for an 8 week clinical trial
with the set inclusion and exclusion criteria. Each patient was assigned to one of the
two study groups: Group 1 (n=25) - 8% arginine and calcium carbonate paste and
Group 2 (n=25) - Diode laser, who received a baseline evaluation of tactile
hypersensitivity with the help of dental explorer and an air blast hypersensitivity. The
effectiveness of the therapy was assessed by VAS Scale of 10, along with the hard
and soft tissue evaluation, at 4 examination periods: 1) immediately after the
application of the diode laser 2) after 15 days 3) after 4 weeks & 4) after 8 weeks. 8%
arginine and calcium carbonate showed significant results (67.27%) than diode laser
(56.55%) at immediate and 4 weeks evaluation by mechanical stimulus and
immediate evaluation by air stimulus. Diode laser showed highly significant results in
progressive decrease in the dentin hypersensitivity till 8 weeks whereas 8% arginine
showed highly significant results till 4 weeks. The immediate efficacy of 8% arginine
and caco3 was higher as compared to diode laser. Diode laser showed progressive
reduction till 8 weeks whereas showed progressive reduction only till 4 weeks.
An in vivo study was conducted by Harshul Sharma et al, to evaluate
the efficacy of MI varnish and Clinpro XT varnish in reducing dentinal
hypersensitivity. Patients with cervical dentinal hypersensitivity were selected for the
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[Type text] Page 19
study. The teeth to be tested were isolated. Then, a blast of air and ice cold water was
applied on the tooth surface and the score was measured by visual analog scale. The
patients were randomly assigned to one of the treatment groups (Group 1: MI varnish;
Group 2; Clinpro XT varnish). The sensitivity scores were recorded immediately and
after 1 week of therapy. Although both varnishes were shown to reduce the dentinal
hypersensitivity in patients, MI Varnish was a better agent to reduce dentinal
hypersensitivity than Clinpro XT varnish.
An in vivo study was conducted by Marilia De Lima Soares et al, to compare
the efficacy of neodymium-doped yttrium-aluminum garnet (Nd:YAG) laser, gallium-
aluminum-arsenide (GaAlAs) laser and 2% neutral fluoride gel in the treatment of
dentinal hypersensitivity. Twenty-three patients were evaluated, involving a total of
48 quadrants with at least 1 tooth with dentinal hypersensitivity. Pain intensity was
recorded on a visual analog scale at the time of clinical examination (baseline),
immediately after treatment, and 1 week post treatment. Teeth were treated with 60
seconds of 2% neutral fluoride gel application or 60 seconds of laser treatment
Nd:YAG laser at a distance of 0.5 cm or GaAlAs laser in contact as well as sham
treatments so that patients remained blind to their treatment group. All treatments
provided adequate pain reduction immediately post treatment, but laser treatments
resulted in significantly greater reductions in pain intensity.
An in vitro study was conducted by Sneha Anil Rajguru et al, to compare the
effects of two desensitizing dentifrices containing NovaMin and arginine on dentinal
tubule occlusion with and without citric acid challenge in vitro using confocal laser
scanning microscopy (CLSM).Forty dentin discs were randomly divided into Groups
I and II containing twenty specimens each, treated with NovaMin and arginine
containing dentifrices, respectively. Groups I and II were divided into subgroups A
and B where IA and IIA underwent CLSM analysis to determine the percentage of
tubule occlusion while IB and IIB underwent 0.3% citric acid challenge and CLSM
analysis. A novel grading system was devised to categorize tubule occlusion. In
Group II, the percentage of occluded tubules was highest for IIA and least for IIB
having statistical significance. In Group I, the difference between IA and IB was
statistically insignificant. On the comparison between IB and IIB statistically
indifferent result was obtained, whereas the difference between IA and IIA was
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statistically significant.The results of grading system were for IA 50% of samples
belonged to Grade 2, for IIA 60% Grade 3, and for IB 70% and for IIB 90% Grade 2.
Dentinal tubule occlusion with arginine containing dentifrice was significantly higher
than NovaMin. However, it could not resist citric acid challenge as effectively as
NovaMin. The effects of NovaMin were more sustainable as compared to arginine
containing dentifrice, thus proving to be a better desensitizing agent.
An in vitro study was conducted by Sian Bodfel Jones et al, to evaluate the
ability of a dentifrice containing the bioactive material calcium sodium
phosphosilicate (CSPS) to remineralise the surface of dentine and physically occlude
patent tubules in a 20 day in situ randomised clinical study. Changes in surface
microhardness and surface topography of dentine specimens treated for 5, 10, 15 and
20 days, twice daily with either a dentifrice containing 5% CSPS or a fluoride-only
containing placebo dentifrice were compared. The substantivity of any mineral
deposits formed on the surface of dentine were investigated by the application of an
intra-oral dietary acid challenge twice daily during the final 10 days of treatment.
After 5 and 10 days of treatment, the dentine samples in both treatment groups
demonstrated an increase in surface microhardness. After 10 days of treatment the
increase in surface hardness was directionally greater for the specimens treated with
5% CSPS dentifrice. Introducing an intra-oral acid exposure resulted in a reduction in
surface micro-hardness which was significantly greater for the specimens treated with
the placebo dentifrice compared to the dentifrice containing 5% CSPS, at day 20.
Occlusion of the patent tubules was evident at each time-point and was significantly
greater for the 5% CSPS containing dentifrice on days 5 and 10. On day 15 both
dentifrices demonstrated the same degree of occlusion. This in situ study
demonstrated that dentifrice containing 5% CSPS may have potential to mineralise
and occlude the dentine in the oral environment.
An in vitro study was conducted by Ryan C. Olley et al, to investigate the
dentine occlusion and acid resistance of dentifrices developed to treat dentine
hypersensitivity. This was a single centre, single blind, randomised, split mouth, four
treatments, two period crossover, in situ study in healthy subjects. Subjects wore
buccal intra-oral appliances each fitted with four dentine samples over four
consecutive days with one study product applied per appliance; 8% strontium acetate
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in silica base, 1040 ppm sodium fluoride (Sensodyne1 Rapid Relief), 8% arginine,
calcium carbonate, 1450 ppm sodium monofluorophosphate (Colgate Sensitive Pro-
Relief1), 1450 ppm sodium fluoride (control paste) and water. On days 3 and 4, two
agitated grapefruit juice challenges (ex vivo) occurred for 1 min. At the end of each
treatment day 1 dentine sample was removed from each appliance for scanning
electron microscopy (SEM). The extent of tubule occlusion was measured using an
examiner-based visual scoring index. In total, 28 subjects completed the study. On
day 2, both test dentifrices demonstrated significantly better dentine tubule occlusion
than water and control paste (8% strontium and 8%). After 3 and 4 days of twice
daily brushing with acid challenges on days 3 and 4 the strontium-based dentifrice
demonstrated significantly better dentine occlusion than all other treatments
Strontium acetate and arginine-based dentifrice result in statistically significant
dentine tubular occlusion compared to controls, but the arginine-based dentifrice is
more susceptible to acid challenge.
An in vitro study was conducted by Karl Anton Hiller et al, to evaluate the
effect of toothpastes with different active ingredients on dentin permeability using an
extended protocol including multiple applications and several thermal ageing cycles
in the presence or absence of human saliva. The Null hypothesis was that dentin
permeability of a hydroxyapatite containing toothpaste (BR), a potassium nitrate (SP)
and an arginine and calcium carbonate (EH) containing toothpaste were similar.
Dentin permeability was measured as hydraulic conductance using a commercially
available capillary flow system (Flodec, Geneva) and results were expressed as %
relative to matching controls. Without saliva, the ranking (best first) of dentin
permeability was BR(61%) < SP(87%) < EH(118%), with saliva EH(63%) <
SP(72%) < BR(88%). Saliva increased or decreased permeability dependent upon the
test material. BR reduced dentin permeability significantly more in absence of saliva,
with saliva EH was superior to BR. Repeated material application decreased and
thermal ageing increased dentin permeability. The different tooth pastes reduced
permeability differently, the best being BR without saliva, the least EH without saliva.
The newly introduced test conditions (ageing, saliva, multiple applications)
influenced single results significantly.
Material And Methods
[Type text] Page 22
MATERIALS AND METHODS:
SOURCE OF DATA:
Forty five extracted maxillary premolar teeth were collected from the
Department of Oral and Maxillofacial Surgery, P.M.N.M Dental College and
Hospital, Bagalkot.
MATERIALS USED IN THE STUDY:
• Distilled water with thymol
• Artificial Saliva
• Scaler
• Low speed hand piece
• Low speed Diamond saw
• High speed round diamond bur
• 1% citric acid
• Rhodamine B isothiocyanate dye
• Sodium fluoride varnish
• Er:YAG laser
• Scanning Electron Microscope (SEM)
Material And Methods
[Type text] Page 23
• Confocal Laser Scanning Microscopy (CLSM)
METHODS OF COLLECTION OF DATA
Freshly extracted maxillary premolar teeth were collected and stored in 4oC
distilled water with thymol until further processing.
INCLUSION CRITERIA:
• Maxillary first premolar teeth.
• Teeth with completely formed apices.
• Non carious teeth.
EXCLUSION CRITERIA:
• Carious teeth.
• Fractured teeth.
• Restored teeth.
METHODOLOGY:
Forty five intact human premolars stored in distilled water (4°C) mixed with
thymol was used in this study. Prior to their preparation, soft tissue and debris was
removed using a scaler and a low-speed handpiece with non-fluoride pumice powder.
A 3-mm-thick horizontal slice was prepared from the cemento-enamel junction of
each tooth using a slow-speed diamond saw. Each slice was transversely separated
into two halves as buccal and lingual. To expose the dentinal tubule orifices, the
cementum layer from each slice was removed with a high-speed bur. Smear layers on
the dentinal tubule orifices will be removed by 1% citric acid for 5 min and then
samples was washed with distilled water. By this way 90 samples was obtained and
these samples was randomly divided into six equal groups. Groups A, B, C and D was
used for the evaluation of tubule occlusion with SEM.
Groups B, D, E and Group F were applied with sodium fluoride varnish and
Group C, D and Group F was irradiated using a Er:YAG laser Group A was untreated
Material And Methods
[Type text] Page 24
and served as control group. Groups E and F was separated for dentin permeability
with CLSM
Er:YAG Laser Irradiation:
For groups C, D and F, following sodium fluoride varnish application, the
dentine specimens was irradiated with an Er:YAG laser with a straight quartz round
tip of 600 µm diameter at an energy level of 60 mJ/pulse and a repetition rate of 30
Hz, without water irrigation.The laser beam was swept in a mesio-distal fashion for
10 sec with the beam directed perpendicularly to the dentine surface in non-contact
mode at a distance of 3–4 mm.
Dentin Analysis Via Confocal laser Scanning Microscopy:
Topical sodium fluoride applied to the samples of groups E and F was labelled
with rhodamine B isothiocyanate dye (0.1% by weight) to determine the effect of
different methods over the penetration depth of the potassium fluoride varnish. CLSM
was used in fluorescent mode to obtain images. A Helium-neon laser was used as the
light source.
Dentin Analysis Via Scanning Electron Microscopy:
The potential of sodium fluoride to occlude dentin tubules totally or partially was
evaluated as the samples of groups A, B, C and D was washed with deionised water
and gently dried with air by using a three-in-one syringe. The samples was coated
with a thin layer of gold (20–30 nm) under vacuum in an ion-sputtering device in
order to increase conductivity. Following SEM images was recorded. Image analysis
were performed at 2000x to determine the diameter of the open tubules.
STATISTICAL ANALYSIS:
The scores thus obtained were tabulated and statistically analyzed by
Kolmogorov Smirnov test, Analysis of variance (ANOVA) followed by Tukeys
posthoc procedures and independent tests were applied.
Sample size estimation
Page | 26
Sample size
Standard deviation in the 1st group S1 =.20
Standard deviation in the 2nd
group S2 =.25
Mean difference between 1st and 2
nd sample =0.2974=d
Effect Size =1.32177777777778
Alpha Error (%) = 5
Power (%) = 95
Sided = 2
Number needed (n)= 15 in each group should be taken
Formula
212/12
2βα
2
z+zd
)(S=n
Where, Z1-α/2= Z-value for α level= 1.96
Z1-β= Z-value for β level= 1.682
Results
Page | 27
Table 1: Normality of tubules diameter of dentinal tubules scores by Kolmogorov
Smirnov test
Groups Z-value p-value
Tubules diameter scores
Group A 0.7360 0.6510
Group B 1.1690 0.2424
Group C 0.6400 0.8070
Group D 0.5230 0.9480
Table 2: Normality of depth of penetration of die in dentinal tubules scores by
Kolmogorov Smirnov test.
Depth of penetration of die in dentinal tubules
Group E 0.3890 0.9980
Group F 0.5250 0.9460
Table 3: Summary of tubules diameter scores in four study groups (A, B, C and D)
Groups N Min Max Mean SD SE
Group A 15 4.25 5.21 4.73 0.20 0.05
Group B 15 3.55 4.60 3.75 0.25 0.06
Group C 15 2.40 2.86 2.60 0.13 0.03
Group D 15 1.35 2.05 1.71 0.16 0.04
Table 4: Comparison of four study groups (A, B, C and D) with respect to mean
tubules diameter scores by one way ANOVA
Sources of
variation
Degrees of
freedom
Sum of
squares
Mean sum
of squares
F-value p-value
Between groups 1 1628.03 1628.03 107.3176 0.0001*
Within groups 28 424.77 15.17
Total 29 2052.80
*p<0.05
Results
Page | 28
Table 5: Pair wise comparisons of four study groups (A, B, C and D) with respect to
mean tubules diameter scores by Tukeys multiple posthoc procedures
Groups Group A Group B Group C Group D
Mean 4.73 3.75 2.60 1.71
SD 0.20 0.25 0.13 0.16
Group A -
Group B P=0.0002* -
Group C P=0.0001* P=0.0002* -
Group D P=0.0001* P=0.0001* P=0.0001* -
*p<0.05
Note: * indicates difference between two groups found to be statistically significant
Table 6: Comparison of two study groups (E and F) with respect to mean depth of
penetration of die in dentinal tubules scores by independent t test
Groups n Mean SD SE t-value P-value
Group E 15 35.07 3.52 0.91 10.3594 0.0001*
Group F 15 20.33 4.24 1.09
*p<0.05
Results
Page | 29
Graph 1: Comparison of four study groups (A,B,C and D) with respect to mean of
tubules diameter of dentinal tubules scores.
0.00
0.50
1.00
1.50
2.00
2.50
3.00
3.50
4.00
4.50
5.00
Group A Group B Group C Group D
4.73
3.75
2.60
1.71
0.20 0.25 0.13 0.16
Mea
n v
alue
Mean SD
Results
Page | 30
Graph 2: Comparison of two study groups (E and F) with respect to mean depth of
penetration of die in dentinal tubules scores
0.00
5.00
10.00
15.00
20.00
25.00
30.00
35.00
40.00
Group E Group F
35.07
20.33
3.52 4.24
Mea
n v
alue
Mean SD
Discussion
Page | 31
DISCUSSION
In current study, the efficacy of a sodium fluoride desensitizing varnish in
combination with Er:YAG laser irradiation for treatment of dentin tubule occlusion
was assessed. Citric acid has been reported to be the preferred agent to expose
dentinal tubule orifices. Thus, soaking in freshly prepared dentin discs in 1% citric
acid for 5 min was used to eliminate the remnants of the naturally-occurring smear
layer with no harmful effects on the surface structure. Topical application of sodium
fluoride exerts a beneficial desensitizing effect on exposed dentine and cementum.1
Sodium fluoride, relies on interactions occurring between sodium fluoride
(NaF) and calcium ions in dentinal fluid. At the end of this reaction, calcium fluoride
crystals (CaF2) form that are deposited on the dentinal tubules, mechanically
occluding the opening. However, as these crystals are small in diameter (about
0.05mm), the application of NaF solution alone may not be effective in narrowing the
diameter of dentinal tubules of hypersensitive teeth and may require repeated
applications. To overcome this limitation, the use of NaF in different forms (i.e
varnish, gel), combination of sodium fluoride with other chemicals such as tricalcium
phosphate, resin and application of sodium fluoride with laser systems may be
proposed.4
The laser parameters having an effect on the amount of energy applied to a
given surface include power level (W), exposure time (seconds), energy density
(J/cm2), distance from the surface and the angle between the target tissue and the tip.
When the Er:YAG laser power level is more than 1.5 W/cm2, it is likely that the
dentin cracks and fissures and the dentin’s protein structure alter, causing damage to
the pulp.5
Er:YAG lasers are effectual in both medical and dental applications because of
having a thermomechanical ablation mechanism and because of the high absorption of
their wavelength by water reductions in dentinal hypersensitivity have been reported
with the use of the Er:YAG laser, due to its action of evaporating the water, in the
dentine, which leads to degranulation or coagulation of the organic elements, causing
their accumulation and blockage of dentinal tubules which is most essential for
reduction of dentinal hypersensitivity.8
Recently, application of various lasers, including He-Ne, CO2, Nd:YAG,
Er:YAG and 810-nm diode lasers have been presented as a potential alternative
Discussion
Page | 32
strategy for the treatment of dentinal hypersensitivity. These lasers can result in either
an occluding effect on dentinal tubules or a desensitization effect by reducing the
pulpal nerve’s pain threshold. The occluding effects of these lasers have rarely been
compared. On the other hand, there have been some reports about the biological
effects of low level lasers in decreasing tooth sensitivity. Since the mechanism of low
level lasers is different from that of high level lasers, the comparison of these two
types of effects could be the subject of a new study.8
Since there are many different and often contradictory reports about the
occluding effects of different lasers, the study was mainly aimed at comparing the
effects of Er;Cr:YSGG, Nd:YAG, CO2 and 810-nm diode lasers by scanning electron
microscopy (SEM). Although occluding effects are not the only effect of lasers that
decrease sensitivity, and recently, effects of lasers on nerve ends have also been
considered important, occluding effects are still considered to be the most effective
method for decreasing tooth sensitivity. Therefore, laser therapy should be attempted
in human studies and if successful, then as a part of patients treatment plans as well.11
The laser therapy had no adverse effect on the pulp. In this long term clinical
study, both Nd:YAG and Er,Cr:YSGG lasers and sodium fluoride desensitizer
resulted in a decrease in dentinal hypersensitivity with no adverse effects on tooth
vitality but, factors which influence the treatment of dentinal hypersensitivity are the
the clinical equipment, economy, patient cooperation, time efficiency of application
and clinician’s proficiency with the technique may affect the treatment measures be
used for for treating dentinal hypersensitivity. Randomized and controlled clinical
studies are necessary for finding the most suitable treatment modality.11
The application of desensitizing agents to those dentinal tubules exposed to
the oral environment constitutes the basis of traditional dentinal hypersensitivity
treatment. Desensitizing agents try to constrain painful stimuli either by means of
covering the dentinal tubules with coating mechanisms or by means of adjusting
tubule contents via protein precipitation, coagulation, or the creation of insoluble
calcium complexes. Owing to the fact that the application of tubule sealing agents
brings some drawbacks, such as the need for repetitive applications, extended
duration of treatment and patient compliance, the usage of alternative treatment
modalities has become necessary. The formulation of glutaraldehyde-containing agent
(GCA) consists of fluoride, hydroxyethyl methacrylate (HEMA), glutaraldehyde and
benzalkonium chloride. The glutaraldehyde reacts with the albumin in dentinal fluid
Discussion
Page | 33
that leads to the precipitation of this protein. In the literature, it is claimed that HEMA
polymerization takes place, which leads to the formation of deep tags so that the
dentinal tubules are completely occluded12
Nakabayashi and Honda developed a reactive copolymer consisting of
polymethyl methacrylate and polystyrene sulphonoic acid which bonded to the smear
layer covered dentine. In a longitudinal study, the ability of this resin system to
occlude was evaluated on the different dentine specimens. Presumably, the tubule
occlusion produced by the pain-free resin desensitizer would last long enough (i.e. 1–
2 months) to permit natural physico-chemical reactions to occlude the tubules and
maintain the desensitization.15
The fluoridated dentinal tubule-occluding agent used in treating dentin
hypersensitivity results in immediate relief from dentin hypersensitivity. However, the
agent used to block the dentinal tubules was incapable of binding to the walls of
dentinal tubules and thus was kept in place only by mechanical means; therefore, the
agent could be dissolved by vitamin C solution or worn away by the action of an
electric toothbrush and may eventually become ineffective. Thus the stability of the
fluoridated dentinal tubule-occluding agent is not definitive and its long-term
effectiveness may decrease with time, therefore combination of laser with fluoridated
varnish is used in the current study.18
Gelskey et al used an Nd-YAG laser combined with a He-Ne laser to reduce
dentin hypersensitivity to air by 58% and hypersensitivity to mechanical stimulation
by 61%. Lan and Liu used an Nd-YAG laser to reduce dentin hypersensitivity to air
by 65% and hypersensitivity to mechanical stimulation by 72%. Unfortunately, the
cure rate for treating dentin hypersensitivity using Nd:YAG laser is not very
satisfactory. So in the current study Er:YAG laser is being selected to reduce the
dentinal hypersensitivity. Although low-level lasers and fluoride varnishes present
distinct modes of action, both treatments provided a significant overall relief in
dentine hypersensitivity (particularly for the sharpest pains) and showed similar
performance.19
The desensitizing agents provide a significant relief in sharp painful
symptomatology and can be reapplied, in case of recurrent discomfort, as they consist
of non-invasive methods. Nevertheless, the ideal treatment technique, one which
should not irritate the pulp, nor cause pain, should be easy and practical to perform,
effective for a long period, as well as accessible to the great majority of population, is
Discussion
Page | 34
still to be developed. There is a need for a more systematic approach to the clinical
management of cervical dentine hypersensitivity, particularly in determining the long-
tem effect of the currently available desensitizing agents. For more effective
treatment, further investigation is required to increase the understanding of the
mechanisms and aetiology of dentinal pain. The findings revealed by both laboratory
and clinical research are extremely important to support the development or
improvement of therapies that may acutely contribute to the treatment of dentinal
hypersensitivity sufferers.20
Er:YAG laser is considered as a gold standard for the treatment of dentinal
hypersensitivity because it has been shown to have the capacity to obliterate the
dentinal tubules, by melting and resolidifying dentin, without pulp injuries or cracks
in irradiated dentin, when used with an adequate protocol. Moreover, a depth of
sealing of 4 μm within the dentinal tubules has been shown, so that there was
immediate improvement of dentinal hypersensitivity. However, little is known about
its in vivo effects in the long term and associations with other treatments. The
Er:YAG laser had an additional analgesic effect when compared with the other high-
power lasers. This probably occurred because the irradiation might have temporarily
altered the final part of the sensory axons and blocked both the C and Aβ fibers,
preventing the patient from feeling pain.22
Low intensity laser irradiation is capable of occluding exposed dentinal
tubules. The occluding effect is proportional to the duration of irradiation when using
the same energy and frequency settings. sixty second of irradiation seemed sufficient
for almost total occlusion of in the irradiated spot. With this duration, heat damage to
the pulp is unlikely to occur with the energy settings used. The main advantage of
Laser is the immediate effect after a single treatment session. Several studies have
shown that Laser can be maintained over time A clinical study compared Er:YAG
Laser to the topical application of 5% sodium fluoride paste which resulted in
effective for the occlusion and narrowing of dentinal tubules for the
treatment of dentinal hypersensitivity.23
According to Landry and Voyer, there is no ideal desensitizing agent and any
treatment for dentin hypersensitivity should be effective by only one application and
should satisfy the following parameters proposed by Grossman (1934): not irritating
pulp, not causing pain, easy application, long-lasting effect, not discoloring or
staining teeth, not irritating soft tissues or periodontal ligament, low-cost.24
Discussion
Page | 35
Er:YAG and Nd:YAG lasers are thought to be able to treat dentin
hypersensitivity by occlusion or narrowing of the dentinal tubules. The Nd:YAG laser
helps to obtain a non-porous structure by melting the surface; Nd:YAG laser
treatment also has an additional analgesic effect by blocking nerve conduction.
Various clinical and laboratory studies have proven the superiority of various laser
types; studies have shown that Er:YAG and Nd:YAG lasers provide similar results
and that two lasers can be used successfully in the treatment of dentinal
hypersensitivity.
The Confocal Laser Scanning Microscope (CLSM) is an optical microscope
that includes a laser light as a light source and an electronic system which helps on
image processing. It obtains high-resolution and extremely thin optical image
sections, removing the interference caused by the light arriving from the different
optical fields across the thickness of the sample and focusing on a single plane
(confocal). Therefore, since the images obtained are digital images, unsuspected
magnifications for optical microscopy can be obtained. CLSM images are notably
higher than those obtained with the conventional optical microscope because the
generated images contain volumetric and texture details impossible to obtain with the
conventional ones. CLSM is a promising imaging method, which enables the
researchers to observe varnish penetration beneath the hard tissues without any
destruction of samples. This systems track fluorescently labelled agents throughout
biological specimens. Depth of penetration of dye in dentinal tubules is obtained by
CLSM image which provide vital details of dentinal hypersensitivity so CLSM is
choosen for current study to evaluate the degree of dye penetration for dentinal
hypersensitivity.31
Scanning Electron Microscope (SEM) allows the visualization of images at
high magnification (50x -10,000 x). In this technique, an electron beam scans the
surface of the sample to produce a variety of signals, the characteristics of which
depend on many factors, including the energy of an electron beam and the nature of
the sample, since a beam of electrons hit the sample and the response is collected by a
detector, as described by Saghiri et al. There is no usage of light and color of sample
does not influence on the image, which is something very important in dentistry,
where dental tissues and dental materials tend to be white or have light colors, which
makes the usage of optical microscopes hard. SEM is used to assess the volume of
dentinal tubules occlusion per square millimeter after the irradiation of Er:YAG laser
Discussion
Page | 36
and sodium fluoride varnish which is useful to know the diameter of tubule occlusion
and number of open dentinal tubules to assess the degree of dentinal
hypersensitivity.32
This study was performed in in-vitro conditions, further long-term in-vivo
studies are required to evaluate the effect of combination of Er:YAG laser and sodium
fluoride varnish in the treatment of dentinal hypersensitivity.
Conclusion
Page | 37
CONCLUSION
Within the limitation of this study of this in vitro study,it can be concluded
that,
1. All the treatment modality for reducing dentinal hypersensitivity were
effective for the occlusion and narrowing of dentinal tubules.
2. The more prominent occlusion was observed in the combined treatment of
Er:YAG laser and sodium fluoride varnish on dentinal hypersensitivity.
3. Therefore, whether used alone or in combination of Er:YAG laser and sodium
fluoride varnish, Er:YAG laser irradiation is effective for the treatment of
dentinal hypersensitivity.
Summary
Page | 38
SUMMARY
Dentin hypersensitivity is a common occurrence and a concern among
patients. It is characterized by short, sharp pain arising from exposed dentin in
response to stimuli, typically thermal, evaporative, tactile, osmotic, or chemical and
which cannot be ascribed to any other dental defect or disease. The two most common
pathways that lead to dentin exposure and dentin hypersensitivity are gingival
recession and enamel erosion.
Er:YAG lasers are effectual in both medical and dental applications because of
having a thermomechanical ablation mechanism and because of the high absorption of
their wavelength by water. The mechanism of Er:YAG laser is the occlusion, by
partial melting, of the exposed dentinal tubules after low intensity irradiation, also, an
analgesic effect of laser irradiation on pulpal nerves may be implicated in the instant
desensitization.
Sodium fluoride gel (NaF), which belongs to the tubule-occluding agents
family is the most commonly used agent by clinicians. This agent’s primary
mechanism relies on the mechanical occlusion that is accomplished by precipitation
of insoluble calcium fluoride crystals within the tubules without adhesion and thus
this agent cannot resist the stresses of the oral environment and degrades over time.
So the combined effect of laser and sodium fluoride varnish is used in current study.
The present study was done to compare and evaluate the combined occluding
effect of sodium fluoride varnish and Er:YAG laser irradiation on dentinal tubules
through scanning electron microscope and confocal laser scanning microscopy. In the
present study forty five extracted maxillary premolar teeth were collected. A 3-mm-
thick horizontal slice was prepared from the cemento-enamel junction of each tooth
using a slow-speed diamond saw. Each slice was transversely separated into two
halves as buccal and lingual. Ninety samples was obtained and these samples was
randomly divided into six equal groups. Groups A, B, C and D was used for the
evaluation of tubule occlusion with SEM. Groups E and F was separated for dentin
permeability with CLSM.
Groups B, D, E and Group F were applied with sodium fluoride varnish and
Group C, D and Group F was irradiated using a Er:YAG laser. The dentine specimens
was irradiated with an Er:YAG laser with a straight quartz round tip of 600 µm
diameter at an energy level of 60 mJ/pulse and a repetition rate of 30 Hz, without
Summary
Page | 39
water irrigation. The laser beam was swept in a mesio-distal fashion for 10 sec with
the beam directed perpendicularly to the dentine surface in non-contact mode at a
distance of 3–4 mm.
Topical sodium fluoride applied to the samples of groups E and F was labelled
with Rhodamine B isothiocyanate dye to determine the effect of different methods
over the penetration depth of the potassium fluoride varnish. CLSM was used in
fluorescent mode to obtain images. A Helium-neon laser was used as the light source.
Groups A, B, C and D was washed with deionised water and gently dried with
air by using a three-in-one syringe. The samples was coated with a thin layer of gold
(20–30 nm) under vacuum in an ion-sputtering device in order to increase
conductivity. SEM images was recorded. Image analysis were performed at 2000x to
determine the diameter of the open tubules.
Normality of tubules diameter and depth of penetration of die in dentinal
tubules scores was statistically analysed by Kolmogorov Smirnov test. The tubules
diameter and depth of penetration of die in dentinal tubules scores follows a normal
distribution. Therefore, the parametric one way ANOVA followed by Tukeys posthoc
procedures and independent tests were applied. Comparison of four study groups (A,
B, C and D) with respect to mean tubules diameter scores was performed by one way
ANOVA. The p value is 0.001.
Pair wise comparisons of four study groups (A, B, C and D) with respect to
mean tubules diameter scores was performed by Tukeys multiple posthoc procedures.
Difference between two groups was found to be statistically significant. Comparison
of two study groups (E and F) with respect to mean depth of penetration of die in
dentinal tubules scores was performed by independent t test. The group E shows
highest dept of penetration of die in dentinal tubules than group F.
Results of the current study shows that combination application of sodium
fluoride and Er:YAG laser on dentinal tubules is the best treatment option for dentinal
hypersensitivity than the application of sodium fluoride varnish and Er:YAG laser
alone.
Bibilography
Page | 40
BIBILOGRAPHY
1. Ogul L, Tunar, Hare Gursoy, Gokser Cxakar, Bahar Kuru, Sebnem Dirikan
Ipci, Selcuk Yılmaz. Evaluation of the effects of Er:YAG laser and
desensitizing paste containing 8% arginine and calcium carbonate and their
combinations on human dentine tubules: a scanning electron microscopic
analysis. Photomed Laser Surg 2014;321:540-545.
2. Gholam Ali Gholami, Reza Fekrazad, Azadeh Esmaiel-Nejad, Katayoun A.M
Kalhori. An evaluation of the occluding effects of Er;Cr:YSGG, Nd:YAG,
CO2 and diode lasers on dentinal tubules: A scanning electron microscope in
vitro study. Photomed Laser Surg 2011;29:115-121.
3. Reza Birang, Jamshid Poursamimi, Norbert Gutknecht, Friedrich Lampert,
Maziar Mir. Comparative evaluation of the effects of Nd:YAG and Er:YAG
laser in dentin hypersensitivity treatment. Lasers Med Sci 2007;22: 21–24.
4. Gokser Cakar, Bahar Kuru, Sebnem Dirikan Ipci, Zeynep Merve Aksoy, Imer
Okar, Selcuk Yilmaz. Effect of Er:YAG and CO2 lasers with and without
sodium fluoride gel on dentinal tubules: A scanning electron microscope
examination. Photomed Laser Surg 2008;26:565-571.
5. Hare Gursoy, Gokser Cxakar, Sxebnem Dirikan Ipci, Bahar Kuru, and Selcuk
Yilmaz. In vitro evaluation of the effects of different treatment procedures on
dentine tubules. Photomed Laser Surg 2012;30:695-698.
6. Rajguru SA, Padhye AM, Gupta HS. Effects of two desensitizing dentifrices
on dentinal tubule occlusion with citric acid challenge: Confocal laser
scanning microscopy study. Indian J Dent Res 2017;28:450-456.
7. Ryan C. Olley, Peter Pilecki, Nathan Hughes, Peter Jeffery, Rupert S. Austin,
Rebecca Moazzez, David Bartlett. An in situ study investigating dentine
tubule occlusion of dentifrices following acid challenge. J Dent 2012;40:585-
593.
8. Wan Hong Lan, Hsin Chen Liu, chun Pin Lin. The combination effect of
sodium fluoride varnish and Nd:YAG laser irradiation on human dentinal
tubules. J Endod 1999;25:424-426.
9. Schwarz F, Arweiler N, Georg T, Reich E. Desensitizing effects of an Er:YAG
laser on hypersensitive dentine. A controlled, prospective clinical study. J Clin
Periodontol 2002;29:211–215.
Bibilography
Page | 41
10. Jones SB, et al. A randomised clinical trial investigating calcium sodium
phosphosilicate as a dentine mineralising agent in the oral environment. J Dent
2014;1:1-8.
11. Sebnem Dirikan Ipci, Gokser Cakar, Bahar Kuru, Selcuk Yilmaz. Clinical
evaluation of lasers and sodium fluoride gel in the treatment of dentine
hypersensitivity. Photomed Laser Surg 2009;27:85-91.
12. Pathan AB, Bolla N, Kavuri SR, Sunil CR, Damaraju B, Pattan SK. Ability of
three desensitizing agents in dentinal tubule obliteration and durability: An in
vitro study. J Conserv Dent 2016;19:31-36.
13. Samet Tosun, Emre Culha, Ugur Aydin, Abdul Semih Ozsevik. The combined
occluding effect of sodium fluoride varnish and Nd:YAG laser irradiation on
dentinal tubules—A CLSM and SEM study. SCANNING 2016;9999:1–6.
14. Ozlem K, Esad GM, Ayse A, Aslihan U. Efficiency of lasers and a
desensitizer agent on dentin hypersensitivity treatment: A clinical study. Niger
J Clin Pract 2018;21:225-30.
15. Sevda Kurt, Tugrul Kirtiloglu, Nasibe Aycan, Yilmaz, Ertan Ertas, Hasan
Orucoglu. Evaluation of the effects of Er:YAG laser, Nd:YAG laser and two
different desensitizers on dentin permeability: In vitro study. Lasers Med Sci
2018;33:765-773.
16. Romeo Umberto, Russo Claudia, Palaia Gaspare, Tenore Gianluca, Del
Vecchio Alessandro. Clinical study treatment of dentine hypersensitivity by
diode laser: A clinical study. J Int Dent 2012;1:1-8.
17. Sandra Ribeiro Cunha, Stephanie Assimakopoulos Garofalo, Tais Scaramucci,
Denise Maria Zezell, Ana Cecilia Correa Aranha. The association between
Nd:YAG laser and desensitizing dentifrices for the treatment of dentin
hypersensitivity. Lasers Med Sci 2017;32:485-493.
18. I. Duran, A. Sengun. The long-term effectiveness of five current desensitizing
products on cervical dentine sensitivity. J Oral Rehabil 2004;31:351–356.
19. Eleftherios-Terry R. Farmakis, Konstantinos Kozyrakis, Marouan G. Khabbaz,
Ulrich Schoop, Franziska Beer, Andreas Moritz. In vitro evaluation of dentin
tubule occlusion by Denshield and Neodymium-doped Yttrium-Aluminum-
Garnet laser irradiation. J Endod 2012;38:662– 666.
20. Felice Femiano, Rossella Femiano, Alessandro Lanza, Michele Lanza, Letizia
Perillo. Effectiveness on oral pain of 808-nm diode laser used prior to
Bibilography
Page | 42
composite restoration for symptomatic non-carious cervical lesions
unresponsive to desensitizing agents. Lasers Med Sci 2016;31:1527-1532.
21. Po-Jen Hsu, Jeng-Huey Chen, Fu-Hsiung Chuang, Rong-Tai Roan. The
combined occluding effects of fluoride-containing dentin desensitizer and
Nd:YAG laser irradiation on human dentinal tubules: An in vitro study. J Med
Sci 2006;22:24–29.
22. N. Gautham Kumar, D.S. Mehta. Short-Term assessment of the Nd:YAG laser
with and without sodium fluoride varnish in the treatment of dentin
hypersensitivity – A Clinical and Scanning Electron Microscopy Study. J
Periodontol 2005;76:1140-1147.
23. Anely Oliveira Lopes, Carlos de Paula Eduardo, Ana Cecilia Correa Aranha.
Evaluation of different treatment protocols for dentin hypersensitivity: An 18-
month randomized clinical trial. Lasers Med Sci 2017;32:700-708.
24. Zahi Badran, Herve Boutigny, Xavier Struillou, Serge Baroth, Olivier Laboux,
Assem Soueidan. Tooth desensitization with an Er:YAG laser: In vitro
microscopical observation and a case report. Lasers Med Sci 2011;26:139–
142.
25. Anisha Merh, Kiran Singhbal, Vaishali Parikh, Sachi Mehta, Gauravardhan
Kulkarni. Comparative evaluation of immediate efficacy of diode laser versus
desensitizing paste containing 8% arginine and calcium carbonate in treatment
of dentine hypersensitivity: An in vivo study. J Evol Med Dent Sci
2015;4:4346-4355.
26. Sharma H, Gupta C, Thakur S, Srivastava S. Comparative evaluation of
calcium phosphate-based varnish and resin-modified glass ionomer based
varnish in reducing dentinal hypersensitivity: A randomized controlled clinical
trial. Eur J Dent 2017;11:491-495.
27. Marilia De Lima Soares, Geane Bandeira Porciuncula, Mara Ilka Holanda
Medeiros De Lucena, Luiz Alcino Monteiro Gueiros,Jair Carneiro Leao,
Alessandra De Albuquerque Tavares Carvalho. Efficacy of Nd:YAG and
GaAlAs lasers in comparison to 2% fluoride gel for the treatment of dentinal
hypersensitivity. J Gen Dent 2016;1:66-70.
28. Karl-Anton Hiller, Wolfgang Buchalla, Isabel Grillmeier, Christina Neubauer,
Gottfried Schmalz. In vitro effects of hydroxyapatite containing toothpastes on
Bibilography
Page | 43
dentin permeability after multiple applications and ageing. Scientific Reports
2018;8:4888.
29. S. A. M. Corona, T. N. Do Nascimento, A. B. E. Catirse, R. F. Z. Lizarelli, W.
Dinelli, R. G. Palma-dibb. Clinical evaluation of low-level laser therapy and
fluoride varnish for treating cervical dental hypersensitivity. J Oral Rehab
2003;30:1180-1189.
30. Pamir T. The efficacy of three desensitizing agents in treatment of dentin
hypersensitivity. J Clin Pharm Ther 2005;30:73–6.
31. Ariadna Garcia-Herraiz, Rafael Leiva-García, Francisco Javier Silvestre, Jose
Garcia-Anton. Applications of Confocal Laser Scanning Microscopy in
dentistry study of the changes of the post-extraction sites. Current Micro Adv
Sci Tech 2012:1:569-581.
32. Thais Cachute Paradella, Marco Antonio Bottino. Scanning Electron
Microscopy in modern dentistry research. Braz Dent Sci 2012;15:43-48.
P.M.N.M Dental College and Hospital, Bagakot
Department of Conservative Dentistry and Endodontics
WRITTEN CONSENT
Dear Sir / Madam,
This is to inform you that your extracted teeth will be stored and used for a research
study being conducted by Dr. SAHIL R. KAWLE, Post graduate student, Department of
Conservative Dentistry and Endodontics, P.M.N.M Dental College, Bagalkot.
Your participation in the research is voluntary.
Dr. SAHIL R. KAWLE
PG Student
Department of Conservative Dentistry and Endodontics
P.M.N.M Dental College, Bagalkot.
Name of the patient:
Age:
Sex:
Contact:
Dear doctor,
I have no objection to donate the extracted teeth for research purpose and I hereby give my
voluntary consent.
Date and time:
Place:
“A COMPARATIVE EVALUATION OF THE COMBINED OCCLUDING EFFECT OF
SODIUM FLUORIDE VARNISH AND ER:YAG LASER IRRADIATION ON
DENTINAL TUBULES-A CONFOCAL LASER SCANNING MICROSCOPE AND
SCANNING ELECTRON MICROSCOPE- AN IN VITRO STUDY.”
PROFORMA
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GROUP A
GROUP B
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GROUP C
GROUP D
GROUP E (SODIUM FLUORIDE) DEPT OF PENERATION OF DIE IN
DENTINAL TUBLES
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GROUP F (SODIUM FLUORIDE +
Er:YAG LASER)
DEPT OF PENERATION OF DIE IN
DENTINAL TUBULES
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Scanned by CamScanner
Scanned by CamScanner
COLOUR PLATE 1
Teeth specimens for study
Tooth section of specimens
STUDY SPECIMENS
COLOUR PLATE 2
Armamentarium
Er:YAG Laser
COLOUR PLATE 3
Tooth Sectioning Sodium Fluoride varnish
Application
Rhodamine B dye Application Er:YAG Laser Application
PROCEDURE
COLOUR PLATE 4
Scanning Electron Microscope
Confocal Laser Scanning Microscopy
COLOUR PLATE 5
GROUP A SEM IMAGE GROUP B SEM IMAGE
GROUP C SEM IMAGE GROUP C SEM IMAGE
SEM IMAGES
COLOUR PLATE 6
GROUP E CLSM IMAGE
GROUP F CLSM IMAGE
CLSM IMAGES