Dentin hypersensitivity and toothache among patients diagnosed with Molar-Incisor Hypomineralization: A systematic review and meta-analysis

OBJECTIVES

To determine the prevalence of dentin hypersensitivity (DH) and toothache in patients with Molar-Incisor Hypomineralization (MIH); and evaluate whether patients with MIH have greater likelihood of presenting DH/toothache than controls.

DATA

Studies evaluating DH/toothache in patients with MIH were included. Studies focusing on other enamel defects were excluded.

SOURCES

Eight databases, including grey literature, were searched in January 2024.

STUDY SELECTION

The methodological quality of studies was assessed using the Joanna Briggs Institute checklist for Cross-sectional studies. Proportion and association meta-analyses, subgrouped by diagnostic methods, were conducted. The certainty of evidence was assessed using GRADE approach.

RESULTS

Fifteen studies were included in the qualitative analysis and fourteen in the meta-analyses. Two studies fulfilled all items of the methodological quality checklist. The overall prevalence of DH/toothache among patients with MIH was 45 %. Prevalence rates of 30 %, 47 %, and 55 % were estimated based on proxy reports, self-reports, and air stimulation, respectively. The overall prevalence of DH/toothache per tooth was 22 %, ranging from 16 % to 29 % according to the diagnostic method. Patients with MIH demonstrated higher likelihood of presenting proxy reports of DH/toothache compared to those without MIH (OR: 1.51, 95 % CI [1.23-1.85], P < 0.01, I2: 0 %). The certainty of evidence was very low, mainly due to the low methodological quality of included studies and high inconsistency.

CONCLUSIONS

The global prevalence of DH/toothache was 22 %, per tooth, and 45 % per patient. Estimates vary according to diagnostic methods. Patients with MIH showed higher likelihood of presenting proxy reports of DH/toothache than controls.

CLINICAL SIGNIFICANCE

This systematic review contributes valuable information to the dental literature by assessing the prevalence and associated factors of DH/toothache in patients with MIH. The findings can guide future research, inform clinical practices and public policy makers, and ultimately improve the management of oral health of patients with MIH.

REGISTRATION

PROSPERO CRD42023432805.

Assessment of color changes and adverse effects of over-the-counter bleaching protocols: a systematic review and network meta-analysis

OBJECTIVES

To assess color change efficacy and the adverse effects of varied over-the-counter (OTC) bleaching protocols.

METHODOLOGY

The study included randomized clinical trials evaluating color changes from OTC bleaching agents. Nine databases were searched, including the partial capture of the grey literature. The RoB2 tool analyzed the individual risk of bias in the studies. Frequentist network meta-analyses compared treatments through common comparators (∆Eab* and ∆SGU color changes, and tooth sensitivity), integrating direct and indirect estimates and using the mean and risk differences as effect measures with respective 95% confidence intervals. The GRADE approach assessed the certainty of the evidence.

RESULTS

Overall, 37 remaining studies constituted the qualitative analysis, and ten composed the meta-analyses. The total sample included 1,932 individuals. ∆Eab* was significantly higher in groups 6% hydrogen peroxide (HP) strips (≥ 14 h). ∆SGU was significantly higher in groups at-home 10% carbamide peroxide (CP) (≥ 14 h), followed by 6% HP strips (≥ 14 h) and 3% HP strips (≥ 14 h). At-home 10% CP (7-13 h) and placebo showed lower risks of tooth sensitivity without significant differences between these treatments.

CONCLUSION

Considering the low level of evidence, OTC products presented satisfactory short-term effects on tooth bleaching compared to the placebo, with little to no impact on dentin hypersensitivity and gingival irritation.

CLINICAL RELEVANCE

OTC products are proving to be practical alternatives for tooth whitening. However, patients should be advised about the possible risks of carrying out such procedures without professional supervision.

Effect of topical application of ibuprofen/arginine on the in-office bleaching-induced tooth sensitivity: A randomized, triple-blind controlled trial

OBJECTIVE

The application of anti-inflammatories as topical desensitizers before dental bleaching is an approach to reduce bleaching-induced tooth sensitivity (TS). This randomized controlled trial compared the risk and intensity of TS and the color change resulting from in-office dental bleaching after using an experimental desensitizing gel containing ibuprofen and arginine.

METHODS

Sixty-two participants with upper canine shades A2 or darker were randomly assigned to either the ibuprofen-arginine desensitizing group or the placebo group. The desensitizing gel was applied for 15 min before in-office bleaching with 35 % hydrogen peroxide gel for 50 min (2 sessions). To assess the absolute risk and intensity of TS, visual (0-10) and numeric rating (0-5) scales were used, and group comparisons were made using the McNemar test, Wilcoxon test, and paired Student t-test (α = 0.05). Color change was evaluated using Vita Classical, Vita Bleachedguide (ΔSGU), and Vita EasyShade (ΔEab, ΔE00, and ΔWID) before and one month after the bleaching procedure. Group comparisons for color change were done using a paired t-test (α = 0.05).

RESULTS

The odds ratio for TS was 0.14 [95 % CI 0.02 to 0.6], meaning lower odds of TS for the desensitizing gel. A lower intensity of TS was also observed for the experimental group (p < 0.005) up to 48 h after bleaching. All color evaluation tools demonstrated effective and similar whitening for both groups (p > 0.05).

CONCLUSIONS

Using the experimental desensitizing gel containing ibuprofen and arginine effectively reduced the risk and intensity of TS without compromising the bleaching efficacy.

CLINICAL RELEVANCE

The topical application of ibuprofen/arginine on the in-office bleaching reduced risk and intensity of bleaching-induced tooth sensitivity.

Comparison of in-office and at-home bleaching techniques: An umbrella review of efficacy and post-operative sensitivity

Objectives

The objective of this umbrella review is to evaluate the efficacy and adverse effects of different teeth whitening techniques in-office (IO) and at-home (AH), regarding chromatic changes and teeth sensitivity.

Materials and methods

The search was carried out from several databases. The included studies were all systematic reviews with or without meta-analysis of RCT or quasi-RCT. The participants were patients that underwent external dental bleaching in permanent vital teeth. The interventions were in-office (IO) bleaching techniques and at-home (AT) bleaching techniques with different bleaching agents and concentrations.

Results

The search resulted in a total of 257 articles, and 28 SR were included in the qualitative analysis and nine in the quantitative analysis. There is no difference between in-office and at-home techniques in terms of color change (p = 0.95) and post-treatment sensitivity (p = 0.85). There is similarity risk and intensity of teeth sensitivity between AH and IO bleaching. IO bleaching with light-activated systems with low concentrations of bleaching agent showed similar results to IO bleaching techniques with high concentrated bleaching gels. With the application of the criteria of the AMSTAR 2 tool, the reviews were considered critically low to high.

Conclusions

There are no significant differences in terms of color change between the different bleaching techniques compared. Teeth sensitivity is always present regardless of the technique used. The use of light activation systems did not increase the intensity and risk of post-operative sensitivity.

Molar incisor hypomineralization and oral health-related quality of life: a sample of 8-12-years-old children

OBJECTIVES

The study aimed to evaluate the impact of molar incisor hypomineralization (MIH) and tooth sensitivity on the oral health in terms of the quality of life (OHRQoL). In addition, the impact of tooth maturity on tooth sensitivity was evaluated in the study.

MATERIALS AND METHODS

Children aged 8-12 years with and without MIH participated in this descriptive cross-sectional study. They were chosen through the convenience sample technique. The Pediatric-Oral-Health-related-Quality-of-Life (POQL) scale was used to assess OHRQoL. The presence of the MIH and decayed, filled and missing teeth due to caries (using dmft/s, DMFT/S indexes) were recorded. The tooth sensitivity and dental maturity status were evaluated with the Shiff-Cold-Air-Sensitivity-Scale (SCASS) and Demirjian-method, respectively. Statistical analysis of the data was performed by Pearson Chi-Square Test and Mann-Whitney U test (p<0.05).

RESULTS

In this study, the participants were a total of 260 children, half were affected by the MIH. Their mean POQL scores were higher than those of the children without MIH with a statistically significantly difference in the total child scale score (p=0.014). Among the children with the MIH, child total QoL score was found to be higher in SCASS positive response group (p=0.011). The teeth with MIH (p<0.001) showed higher response to the stimulus. According to the dental age and dental maturity categories of the children with MIH, the total child scale score was found to be higher in the SCASS category (p=0.011), and the response status to the SCASS was statistically significant (p=0.042 and p=0.05, respectively).

CONCLUSIONS

Among the children with MIH, the OHRQoL was found to be negatively affected. The teeth with the MIH tend to reveal more tooth sensitivity than healthy teeth. Many conditions such as having MIH, and tooth sensitivity might have an impact on the OHRQoL. In addition, more sensitivity to the stimulus was observed in the teeth with lower tooth maturity status; the dental age and dental maturity might have effects on tooth sensitivity.

CLINICAL RELEVANCE

Considering the negative impacts due to MIH, the evaluation of OHRQoL is critical for dentists to employ a well-defined guide in their clinical decisions.

Glutaraldehyde-based desensitizer does not influence postoperative sensitivity and clinical performance of posterior restorations: A 24-month randomized clinical trial

OBJECTIVES

To evaluate the influence of a glutaraldehyde-based desensitizer (GL) on postoperative sensitivity (POS) in posterior bulk-fill resin composite restorations using an adhesive applied in the self-etch (SE) and etch-and-rinse (ER) strategies; and to assess the clinical performance of the restorations.

METHODS

Posterior resin composite restorations (n = 228) at least 3 mm deep were inserted in 57 subjects using a split-mouth design. The adhesive was applied with/without prior application of a GL. A resin composite was used for all restorations. Spontaneous POS (risk and intensity), as well as POS caused by stimulation with an air blast and assess the response to horizontal and vertical percussion was assessed using two scales in the baseline and after 7, 14, and 30 days. In addition, some parameters were evaluated using FDI criteria up to 24 months of clinical service.

RESULTS

No significant POS was observed (p > 0.05). A higher absolute risk and intensity of spontaneous POS was observed within 7 days (35.1%), without statistically significant differences among groups. At 24 months 5 restorations were considered clinically unsatisfactory, and 73 restorations showed minor discrepancies in adaptation, with no significant differences between groups (p > 0.05).

SIGNIFICANCE

A GL agent does not influence POS in posterior restorations with bulk-fill resin composite. It may be considered a dispensable clinical step in the restorative protocol.

The effect of combination treatment of CO2-laser irradiation and tetracalcium phosphate/dicalcium phosphate anhydrate on dentinal tubules blockage: an in vitro study

The aim of this study was the evaluation of the in vitro efficacy of a carbon dioxide (CO2) laser, a tetracalcium phosphate/dicalcium phosphate anhydrate (TP/DP) desensitizer and the combination of the desensitizer and additional CO2 laser irradiation as a treatment modality for cervical dentin hypersensitivity. A total of 48 dental specimens, prepared from extracted human premolars and molars, were divided into four groups: a control group, a TP/DP desensitizer paste group, a CO2 laser (10.600-nm wavelength) group, and a paste and laser group. The specimens were coated with nail varnish except in the marked area and were then immersed in 2% methylene blue dye for 1 h. The specimens were then washed, dried, and cut longitudinally. Thereafter, photos of 40 dentin specimens were taken and evaluated. The area of penetration was assessed and reported as percentage of the dentin surface area. Additionally eight dental specimens were examined with the aid of a scanning electron microscope and evaluated. Significant differences in the penetration depth were found for all experimental groups compared to the control group. The lowest penetration area was detected in the paste-laser group (16.5%), followed by the laser (23.7%), the paste (48.5%), and the control group (86.2%). The combined treatment of the CO2 laser and a TP/DP desensitizer was efficient in sealing the dentinal surface and could be a treatment option for cervical dentin hypersensitivity.

Comparative evaluation of diode laser alone and in combination with desensitizing toothpaste in occlusion of dentinal tubules - A SEM study

Background

In regular dental practice, dentinal hypersensitivity is a common oral condition affecting the adult population. Although a variety of treatment procedures are available, there is no single method that proved to be potent in eliminating dentine hypersensitivity and providing patients with complete relief. Hence the present study performed to estimate the occlusion of dentinal tubules using a diode laser alone and in combination with various desensitizing toothpaste, using the scanning electron microscope.

Materials and methods

This in-vitro study consisted of five groups wherein cervical cavities were prepared on the extracted teeth followed by the application of 17% EDTA. The cavities were then treated with Novamin toothpaste, pro-arginine toothpaste, diode laser, and in combinations respectively. Then SEM analysis was done and the results obtained were statistically analyzed using tukey's multiple post hoc analysis for intra and inter group comparisons.

Results

The groups which were treated with a combination of diode laser and the desensitizing agent showed statistically significant (P < 0.05) better dentinal tubule occlusion than other groups.

Conclusion

The use of a diode laser has an added benefit in treating dentinal tubule occlusion when compared to desensitizing kinds of toothpaste.

Influence of smoking on the effectiveness of tooth whitening: a systematic review

OBJECTIVES

Perform a systematic review to evaluate the influence of smoking on the effectiveness of tooth whitening (TW) and to analyze whether tooth sensitivity is different between smokers and non-smokers.

MATERIALS AND METHODS

A systematic review modeled according to the PRISMA guidelines was conducted. PubMed, Embase, Web of Science, Cochrane, Scopus, and OpenGrey databases were searched for related clinical trials. The population, exposure, comparison, outcomes (PECO) was individuals who had TW performed, smoking individuals, non-smoking individuals, and effectiveness of TW, respectively. Risk of bias was assessed with the ROBINS-I tool, and data from included studies were extracted by two researchers independently. The certainty of the evidence was evaluated using the GRADE (Grading of Recommendations, Assessment, Development, and Evaluations) approach.

RESULTS

Five studies were selected for qualitative analysis. The ROBINS-I tool classified 3 studies as having a moderate risk of bias, one study as having a serious risk of bias, and one with a critical risk. GRADE performed only for color change results and showed a low certainty of evidence. Limited evidence suggests that effectiveness of TW between smokers and non-smokers is similar. The tooth sensitivity also does not seem to be influenced by smoking. Due to the heterogeneity of the data, a meta-analysis could not be performed.

CONCLUSIONS

Effectiveness of TW between smokers and non-smokers is comparable. The tooth sensitivity also does not seem to be influenced by smoking.

CLINICAL RELEVANCE

The effectiveness of bleaching among smokers and non-smokers appears to be similar. Tooth sensitivity during TW also appears not to be influenced by smoking.

Use of infrared photobiomodulation with low-level laser therapy for reduction of bleaching-induced tooth sensitivity after in-office bleaching: a double-blind, randomized controlled trial

The purpose of this study is to evaluate the use of infrared photobiomodulation with low-level laser therapy (PBM) to reduce bleaching-induced tooth sensitivity (TS) after in-office bleaching. Eighty-three participants were randomized in blocks into two groups. In the experimental group, the patients received an application after each session of in-office bleaching (35% hydrogen peroxide, 1 × 50 min; 2 sessions with 1-week interval), while the laser application was simulated in the control group. The PBM system was operated in continuous mode, using 3 J of energy. A dose of 100 J/cm2 was applied for 30 s with 808 nm (100 mW of power) in the middle third of the crown. The risk and intensity of TS were recorded immediately after bleaching, 1 h, 24 h, and 48 h after each bleaching session, with a visual scale analog (0-10) and a five-point numerical scale (0-4). The color was recorded at the beginning, weekly, and 1 month after the end of the bleaching (VITA Classical, VITA Bleachedguide, and digital spectrophotometer). The risk of TS was 98% (95% CI 88 to 99%) for the laser group and 95% (95% CI 83 to 99%) for the control (RR = 1.03; 95% CI 0.94 to 1.12; p = 1.0). Similarly, no difference in the intensity of TS was detected for both pain scales (p > 0.65). Improvement in color change, regardless of the group, was observed (p > 0.15). The application of an PBM did not reduce the risk and intensity of TS when applied after the procedure using the parameters recommended by the manufacturer.Trial registration number and date of registration: RBR-4HCVSG-04/06/2019.

Evaluation of the effects of 980 and 810-nm high-level diode lasers in treating dentin hypersensitivity: A double-blinded randomized clinical trial

Background

Dentin hypersensitivity is a prevalent problem, manifested as a short sharp pain. Researchers have used different lasers to treat this condition. The present study aimed to evaluate the effect of 980 and 810-nm high-level diode lasers on dentin hypersensitivity to determine proper laser parameters for clinical applications.

Materials and Methods

In this double-blinded randomized clinical trial, seven patients with 60 teeth affected by dentin hypersensitivity were selected for the present double-blind, randomized clinical trial. The patients' teeth were randomly matched and assigned to three groups: Group 1: 980-nm diode laser; Group 2: 810-nm diode laser; and Group 3: Control, which received only the guiding beam. The laser parameters were 1-W power, continuous wave mode, a distance of 1 mm, no contact, a 45° irradiation angle, and a 30-s exposure time using to-and-fro movements. The treatment consisted of two sessions with a 1-week interval. Pain severity was determined with the visual analog scale (VAS) at all the study intervals using a dry ice spray. The data were analyzed with SPSS version 20 using one-way ANOVA, repeated measures ANOVA, and least significant difference tests. Significance level was set at α = 0.05.

Results

The changes in VAS were significant only in the first stage (P = 0.046). The mean VAS scores decreased over time in the 810-nm and 980 laser groups. A comparison of VAS changes relative to the baseline revealed significant changes in VAS scores at all the time intervals with both lasers. The two 810 and 980-nm laser groups did not exhibit any significant differences for 2 months postoperatively (P = 0.098).

Conclusion

The application of 810 and 980-nm diode lasers at 1-W power and an exposure time of 30 s was effective in decreasing pain in patients with dentin hypersensitivity, with no significant difference between these two lasers.

Resin-based materials to control human dentin permeability under erosive conditions in vitro: A hydraulic conductance, confocal microscopy and FTIR study

OBJECTIVES

To characterize the behavior of three different polymeric agents before and after an erosive challenge on dentin permeability, to analyze their degradation in both conditions, and to analyze their degree of conversion (DC).

METHODS

The permeability of human dentin disks (1.0 ± 0.2 mm) was measured with smear layer, after its removal, after treatment (LpTreat) with Gluma Desensitizer, PRG Barrier Coat (PBC) or Icon infiltrant (n = 11/group) and after exposure to citric acid (LpEro) (6%, pH 2.1, 1 min). The specimens were analyzed under a Laser Scanning Confocal Microscope (n = 2/group) and the products' DC were calculated. Data were subjected to 2-way repeated measures ANOVA and post-hoc Bonferroni (permeability analysis), to paired t-test (for specimens treated with Icon) and to t-test (DC analysis) (α < 0.05).

RESULTS

Icon showed the lowest LpTreat and LpEro values, while PBC and Gluma did not differ from each other under these conditions. Icon and PBC showed LpEro similar to a dentin with smear layer. Under the Laser Scanning Confocal Microscope, more deposits were noticeable on dentin after treating with PBC. Gluma presented the deepest penetration in dentin. The DC of PBC was the highest.

SIGNIFICANCE

Icon caused the highest reduction on permeability values, followed by PBC and Gluma. PBC generated more deposits covering dentin and seemed to be more efficient after an erosive challenge. The association of a polymeric resin with inorganic ion-releasing fillers seem to be a great strategy to manage dentin hypersensitivity under erosive conditions.

The effect of photobiomodulation using low-level laser therapy on tooth sensitivity after dental bleaching: a systematic review

The authors aimed to conduct a systematic review to assess data from the current literature on the effectiveness of low-level laser therapy (LLLT) in preventing tooth sensitivity (TS) after tooth whitening (DB). PRISMA guidelines for systematic reviews were followed. Clinical trials evaluating the treatment of LLLT in patients with sensitivity after tooth whitening were selected. A full bibliographic search was performed on May 4, 2021, in the following databases: Embase, MEDLINE via PubMed, SciELO, VHL Regional Portal, Web of Science, Gray Literature, Scopus, ClinicalTrials.gov and Cochrane Library. This study followed Cochrane's recommendations for analyzing risk of bias. A total of 1054 studies were found (255 studies were excluded because they were duplicates and 785 because of titles and abstracts). Only 14 articles were selected for analysis, of which eight were excluded because they had one or more exclusion criteria, resulting in six articles included in this systematic review, the vast majority being classified as low risk of bias. The studies reviewed indicated that LLLT showed promise in preventing TS after TB. However, evidence is limited and more clinical trials with low risk of bias are needed to reach a definitive conclusion on the action of LLLT in pain control after TB.

LED photobiomodulation effect on the bleaching-induced sensitivity with hydrogen peroxide 35%-a controlled randomized clinical trial

OBJECTIVES

The aim of this study was to evaluate the effect of a protocol of photobiomodulation (PBM) with light-emitting diodes (LED) on the clinical risk of bleaching-induced sensitivity.

MATERIALS AND METHODS

Sixty-four volunteers were selected and randomly divided in two groups, placebo (PG) and LED (LG). The LG received PBM irradiation and tooth bleaching, while the PG received tooth bleaching and simulation of the irradiation. The occurrence of painful sensitivity was recorded during the dental bleaching; immediately after bleaching; and 24, 48, and 72 h after tooth bleaching. At the same measurement times, data were collected on the intensity of sensitivity (VAS and NRS scale) and teeth affected by bleaching-induced sensitivity. A questionnaire sought to measure how the painful sensitivity influenced basic daily activities. Tooth color measures were performed using subjective and objective methods.

RESULTS

LED irradiation decreased the occurrence of sensitivity at all studied evaluation times as well as its intensity, with the exception of the 72-h data when both groups presented no difference. Teeth affected by bleaching-induced sensitivity were significantly greater in the PG. Color measurements presented no differences between the groups in the recently after and later measures.

CONCLUSIONS

PBM with LED decreases sensitivity risk and sensibility intensity during and after office bleaching and causes no influence on the shade degree of whitening achieved. The decrease in tooth sensitivity provided more comfort and less suffering while drinking.

CLINICAL RELEVANCE

LED irradiation is a promising intervention in the control of bleaching-induced sensitivity.

TRIAL REGISTRATION

RBR-7hpfwj. Sensitivity intensity measured by the VAS scale (0-10) in the first whitening session (Graphic A) and second whitening session (Graphic B). Significance level set at ≤ 5%. *Mann-Whiteney U test. Columns followed by the same letter are significant different (ap < 0.001; bp < 0.001; cp < 0.001; dp =0.013; ep < 0.001; fp < 0.001; gp < 0.001; hp = 0.002).

Effects of desensitizing dentifrices on dentin tubule occlusion and resistance to erosive challenges

Background

Many studies have demonstrated efficacy of casein phosphopeptide (CPP) containing products for dentin tubule occlusion for treatment of dentin sensitivity, but their effectiveness under dynamic erosive challenges remains to be elucidated. The purpose of the present study was to investigate the effectiveness of a desensitizing dentifrice containing CPP in occluding dentin tubules and resisting erosive challenges in comparison to that containing polyvinyl methyl ether/maleic acid (PVM/MA) copolymers.

Methods

A total of 33 dentin discs were prepared from coronal sections of human third molars and divided into 3 groups: a toothpaste containing CPP; a toothpaste containing PVM/MA and submicron silica; and a regular toothpaste (Controls). A soft-bristle toothbrush was used to brush the dentin discs with the dentifrices for 45 strokes in 30 s at a force of approximately 200 g. The brushing cycle was repeated after immersion of the dentin discs in artificial saliva overnight. The dentin discs were then challenged in orange juice for 10 min in an incubator rocking at 120 rpm. Three fields were randomly selected on each dentin disk surface to assess dentin tubule occlusions after each brushing cycle and after orange juice challenge with a 3D laser scanning microscope. Specimen cross sections were examined with a scanning electron microscope equipped with energy dispersive spectroscopy (SEM/EDS).

Results

After the first and second cycles of brushing, dentin tubules were occluded on average by 56.3% and 85.7% in CPP group, 66.2% and 88.1% in PVM/MA group, and 0.0 and 13.0% in the controls, respectively. There were no statistically significant differences in dentin tubule occlusions between the CPP and PVM/MA groups after two cycles of brushing (p>0.05). After dynamic erosive challenges with orange juice, 20.3% of the dentin tubules in the CPP group, 79.1% in the PVM/MA group and none in the control remained occluded (P<0.05). SEM/EDS imaging showed that dentin tubules were blocked with plugs containing dentifrice substances in CPP and PVM/MA groups after treatments, but none in the controls.

Conclusions

Desensitizing dentifrices containing CPP or PVM/MA could effectively occlude dentin tubules after two cycles of brushing. PVM/MA in combination with submicron silicon dioxide exhibited stronger resistance to dynamic erosive challenges by acidic beverages. Inorganic fillers that can enter dentin tubules and resist erosive challenges may be key for desensitizing dentifrices.

Bioactive toothpastes in dentin hypersensitivity treatment: A systematic review

The use of bioactive materials is a recent proposal in the treatment of dentin hypersensitivity (DH) due to the ability to stimulate the neoformation of a barrier on dentin surface. Questions have arisen about the effectiveness of the materials to reduce DH when compared to the control groups (placebo or non-bioactive substance). Thus, the aim of this systematic review was to evaluate the randomized controlled trials in adult patients for DH treatment with a dentifrice containing bioactive glass, applied either at-home or in-office. Methods: The study was registered in PROSPERO and followed PRISMA guidelines. Searches were carried out in four databases (Pubmed/Medline, CENTRAL, Wbb of Science, LILACS) spanning from February 2020 to March 2020, with no language or publication date restrictions. A supplementary hand-search was performed by checking the list of references. The so-called gray literature of the national and international databases for theses and dissertations, as well as unfinished, in progress and unpublished studies were also searched. Results: After reading the titles and abstracts, articles that were duplicated (74 records) or unrelated to the systematic review (76 records) were excluded. Fifteen studies were evaluated considering seven at low risk of bias, four at high risk and four at moderate risk. Conclusion: The bioactive compounds at low concentrations (2.5–7.5%) can be used as treatment of DH both at-home and in-office.

The effectiveness of propolis extract in reducing dentin hypersensitivity: A systematic review

OBJECTIVE

This systematic review was performed to evaluate the effectiveness of propolis on dentin hypersensitivity reduction.

DESIGN

The search was conducted in Pubmed, Scopus, Web of science, Latin American and Caribbean Health Sciences Literature data base (Lilacs), Brazilian Library in Dentistry (BBO), Embase, and Cochrane Library aiming to identify relevant randomized clinical trials that evaluated the effect of propolis on dentin hypersensitivity. The Cochrane Collaboration tool was used for assessing the risk of bias.

RESULTS

From the total of 63 articles found in the search, six clinical trials were selected. All studies reported that propolis was more effective in reducing hypersensitivity than the placebo. No side effects were observed.

CONCLUSIONS

Overall, propolis extract can be considered an effective, safe and low-cost alternative to reduce the dentin hypersensitivity.

Is the at-home bleaching treatment applied only on the lingual surface as effective as that on the buccal surface? A randomized clinical trial

OBJECTIVES

This double-blind randomized clinical trial compared the effectiveness and bleaching sensitivity (BS) of at-home dental bleaching performed on the buccal surface and on the lingual surface.

METHODS

Using a split-mouth design, 25 patients were assigned to two bleaching groups: 10% hydrogen peroxide (White Class 10%, FGM) applied once daily for 60 min to the buccal surface (BSB) and 10% hydrogen peroxide (White Class 10%, FGM) applied once daily for 60 min to the lingual surface (LSB), both for 14 days. The color was evaluated before bleaching, after the first and second weeks, and 1 month after the bleaching using Vita Classical and Vita Bleachedguide scales and a Vita Easyshade spectrophotometer. BS was recorded daily using a 0-4 numerical rating scale and a 0-10 visual analogue scale. The following statistical tests were used: color changes (Mann-Whitney), absolute risk of BS (McNemar's exact), and the intensity of BS (Mann-Whitney). In all statistical tests, the significance level was 5%.

RESULTS

Significant bleaching was observed after the end of bleaching in both groups, with higher bleaching effectiveness for BSB when compared to LSB (p < 0.05). Regarding BS, no significant difference was observed between groups (p = 1.00).

CONCLUSIONS

The 10% hydrogen peroxide (White Class 10%, FGM) applied in at-home bleaching performed on the lingual surface did not promote a similar result of color change compared to on the buccal surface. Regarding BS, there was no significant difference between the groups.

CLINICAL RELEVANCE

The at-home bleaching performed on the lingual surface promotes a lower result in the color change. BS is similar between the groups.

CLINICAL TRIAL REGISTRATION NUMBER

RBR-283byt.

Obliterating potential of active products for dentin hypersensitivity treatment under an erosive challenge

OBJECTIVES

To compare the effect of 5 desensitizing agents on the hydraulic conductance (Lp) of dentin and to analyze its surface under a Laser Scanning Confocal Microscope (LSCM) before and after an erosive challenge.

METHODS

Lp was analyzed in the following sequence: in the presence of smear layer (pMin), after a 15-second acid etching (pMax), after treatment with a desensitizing agent (pTreat) and after a 1-minute erosive challenge (6% citric acid - pEro). Fifty 1.0 ± 0.2 mm-thick dentin disks were prepared from sound human third molars and were randomly distributed into 5 groups (n = 10): FG-Fluoride gel (control), SA-Sensiactive, PR-Sensitive Pro-Relief, NP-Desensibilize Nano-P and EV-Enamel Pro Varnish. Data were analyzed by two-way ANOVA and Tukey tests (α<0.05). Additional specimens were analyzed under a Laser Scanning Confocal Microscope (LSCM) and by Energy Dispersive X-ray Spectroscopy (EDS).

RESULTS

All materials reduced the Lp in some extent, except for FG and EV. After the erosive challenge, SA was the only material effectively able to keep the same Lp of the post-treatment phase, while the other products showed lower resistance upon an erosive challenge. Under the LSCM, the SA and NP materials were more effective to obliterate the opened dentin tubules and demonstrated higher resistance upon an erosive challenge. The EDS analysis evidenced levels of Ca, O, P, Si, Na and S.

CONCLUSIONS

Product containing potassium oxalate was the most effective in reducing Lp of dentin samples before and after an erosive challenge. Under a LSCM, products containing potassium oxalate or hydroxyapatite crystals seemed to be occluding the dentin tubules after an erosive challenge.

Analysis of permeability and biological properties of dentin treated with experimental bioactive glasses

OBJECTIVES

To evaluate obliterating capability and biological performance of desensitizing agents.

METHODS

50 dentin blocks were distributed according to the desensitizing agent used (n = 10): Control (Artificial saliva); Ultra EZ (Ultradent); Desensibilize Nano P (FGM); T5-OH Bioactive Glass (Experimental solution); F18 Bioactive Glass (Experimental solution). Desensitizing treatments were performed for 15 days. In addition, specimens were subjected to acid challenge to simulate oral environment demineralizing conditions. Samples were subjected to permeability analysis before and after desensitizing procedures and acid challenge. Cytotoxicity analysis was performed by using Alamar Blue assay and complemented by total protein quantification by Pierce Bicinchoninic Acid assay at 15 min, 24-h and 48-h time points. Scanning electron microscopy and energy dispersion X-ray spectroscopy were performed for qualitative analysis. Data of dentin permeability was analyzed by two-way repeated measures ANOVA and Tukey's test. For cytotoxicity, Kruskal-Wallis and Newman-Keuls tests.

RESULTS

for dentin permeability there was no significant difference among desensitizing agents after treatment, but control group presented highest values (0.131 ± 0.076 Lp). After acid challenge, control group maintained highest values (0.044 ± 0.014 Lp) with significant difference to other groups, except for Desensibilize Nano P (0.037 ± 0.019 Lp). For cytotoxicity, there were no significant differences among groups.

CONCLUSION

Bioglass-based desensitizers caused similar effects to commercially available products, regarding permeability and dentin biological properties.

CLINICAL SIGNIFICANCE

There is no gold standard protocol for dentin sensitivity. The study of novel desensitizing agents that can obliterate dentinal tubules in a faster-acting and long-lasting way may help meet this clinical need.

Topical application of a desensitizing agent containing potassium nitrate before dental bleaching: a systematic review and meta-analysis

OBJECTIVES

To conduct a systematic review and meta-analysis to evaluate the risk and intensity of tooth sensitivity (TS) after topical application of desensitizers containing potassium nitrate before dental bleaching.

METHODS

We searched PubMed, Scopus, Web of Science, LILACS, BBO, Cochrane Library, and SIGLE. We also surveyed gray literature without restrictions. We meta-analyzed the data using the random-effects model to compare potassium nitrate and placebo in terms of risk and intensity of TS and color change (∆SGU or ∆E). The quality of the evidence was rated using the GRADE approach. The risk of bias (RoB) of the included studies was analyzed using the Cochrane RoB tool.

RESULTS

After the database screening, 24 articles remained. A significant 12% lower risk for the groups where desensitizing agents were applied (p = 0.02), with a risk ratio of 0.88 (95% CI 0.78 to 0.98). About the intensity of TS, a significant average mean difference of - 0.77 units of VAS units (95%CI - 1.34 to - 0.19; p = 0.01) in favor of the desensitizer group. In the NRS scale, a significant average mean difference of - 0.36 (95% CI - 0.61 to - 0.12; p value = 0.004) in favor of the desensitizer group. No significant difference was observed in color change (p > 0.28) in ∆SGU and ∆E.

CONCLUSIONS

Although a significant reduction in the risk and intensity of TS was observed in groups treated with a potassium nitrate at some point during the bleaching, the clinical significance of this reduction is subtle and clinically questionable. Color change is not affected by the use of agents.

CLINICAL RELEVANCE

The reduction in the risk and intensity of TS with the topical application of potassium nitrate-based desensitizing agents in dental bleaching is subtle and maybe clinically questionable.

Dental hypersensitivity in individuals with cleft lip and palate: Origin and therapies

Background. Dental hypersensitivity is due to the exposure of the dentin layer after wear of enamel or cementum, exposing the dentinal tubules and the nerve endings of odontoblasts within these tubules. The present study aimed to assess the factors related to dental hypersensitivity in individuals with cleft lip and palate and the most common therapy received.

Methods. The medical records of 536 patients with cleft lip and/or palate (281 males, 255 females) with a mean age of 18 were analyzed in a single center. The inclusion criterion was patients reporting dental hypersensitivity from May 2015 to October 2019. The origin of dental hypersensitivity was evaluated considering orthodontic movement, periodontal diseases, and reversible and irreversible pulpitis. The therapy indicated by the dental professionals for dental hypersensitivity were recorded. Descriptive statistics were performed.

Results. Of 61 teeth with dental hypersensitivity, 10 were attributed to orthodontic movement, 21 to periodontal problems, 27 to reversible pulpitis, and three to irreversible pulpitis. The most used therapies were the application of fluoride varnish and prophylaxis, dentifrice indication for dental sensitivity, free gingival grafts, pulpectomy, desensitizing agent application, conservative endodontic treatment (direct pulp protection), and restoration of non-carious cervical lesions.

Conclusion. Reversible pulpitis was the most prevalent etiologic factor of dental hypersensitivity in individuals with cleft lip and palate. Dentifrices for dental sensitivity and fluoride varnish application were frequently recommended.

Low level laser therapy, Er,Cr:YSGG laser and fluoride varnish for treatment of dentin hypersensitivity after periodontal surgery: A randomized clinical trial

This clinical trial aimed to compare the effects of low-level laser therapy (LLLT), Er,Cr;YSGG laser, and fluoride varnish, as compared to the placebo laser on decreasing dentin hypersensitivity (DH). This randomized, double-blinded clinical trial included 60 jaw quadrants in 24 patients who underwent periodontal surgery. The quadrants were randomly assigned to 4 groups and received treatments as follows. Group 1: LLLT with a combination of red and infrared wavelengths, group 2: Er,Cr:YSGG laser (0.25 W and 0.5 W), group 3: fluoride varnish, and group 4: placebo laser. The sensitivity response to the cold spray was recorded using visual analogue scale (VAS) at baseline, immediately, and 1 week post-treatment. The data were analyzed by repeated measures analysis at the significance level of P<0.05. There was a significant reduction in DH after treatment by low-level lasers, Er,Cr:YSGG laser, or fluoride varnish compared to the baseline data (P<0.05), but the placebo group displayed no significant alteration in DH (P=0.069). At 1 week, the VAS score in the Er,Cr:YSGG laser group was significantly lower than that of the LLLT (P= 0.043) and placebo (P<0.001) groups. Furthermore, the subjects who received fluoride varnish exhibited significantly lower DH compared with the placebo group (P = 0.023). Er,Cr:YSGG laser was the most effective strategy in dealing with DH, as it caused the greatest pain reduction over the study period and showed a significant superiority over LLLT and placebo groups. Alternatively, the application of fluoride varnish could be recommended for attenuating DH following periodontal surgery.

A randomized, controlled, two-month pilot trial of stannous fluoride dentifrice versus sodium fluoride dentifrice after oxalate treatment for dentinal hypersensitivity

OBJECTIVES

To compare the effects of a stannous fluoride dentifrice and a sodium fluoride dentifrice on dentinal hypersensitivity when used with an oxalate-based regimen combining in-office and at-home treatment.

MATERIALS AND METHODS

In this single-center, randomized, controlled, double-blind, pilot clinical trial, 30 subjects were professionally treated at baseline with a 3% oxalate/potassium salt solution on up to two target teeth, then randomized 1:1 to either 0.454% stannous fluoride or 0.243% sodium fluoride overlabeled dentifrice. Both groups were given 6 sensitivity strips (3.14% potassium oxalate gel) and a soft, manual toothbrush. Subjects were permitted to apply strips on up to two teeth, up to three times per tooth, at home as desired throughout the study. Dentinal sensitivity (cold air blast challenge) was assessed at baseline, immediately after post-professional treatment, and at day 60 using the Schiff scale and a Visual Analog Scale (VAS).

RESULTS

Immediately after professional oxalate treatment, the overall mean Schiff and VAS score decreased 25.6% and 22.4% from baseline, respectively (p ≤ 0.001 for both). At day 60, further reductions in both mean scores were seen in both groups. There were no significant differences between the groups at day 60. All treatments were well tolerated.

CONCLUSIONS

In subjects treated with oxalates for dentinal hypersensitivity, both stannous fluoride and sodium fluoride dentifrices are well tolerated, are feasible for routine use, and do not detract from the desensitizing effects of an in-office and at-home oxalate combination treatment regimen.

CLINICAL RELEVANCE

Either stannous fluoride or sodium fluoride dentifrices can be recommended to dentinal hypersensitivity patients who undergo professional oxalate treatment.

An in vitro analysis of the effect of adjunctive use of ozonated oil with a desensitizing agent on dentinal tubule occlusion

Introduction

Dentinal hypersensitivity (DH), is a commonly encountered clinical problem, the management of which is by two main approaches that involve blockage of nerve activity and tubular occlusion. Desensitizing agents containing arginine and calcium carbonate have emerged effective in occluding tubules. Ozone removes the smear layer and opens up the dentinal tubules for easy penetration of these desensitizing agents.

Objective

To comparatively evaluate the effect of ozonated oil on the patency and occlusion of dentinal tubules with and without adjunctive application of a desensitizing agent containing arginine.

Materials and methods

80 dentin specimens that were distributed into 4 groups as Group 1 (control), Group 2 (ozonated oil), Group 3 (desensitizing agent) and Group 4 (desensitizing agent following the application of ozonated oil), underwent an acid challenge. Scanning electron microscopic (SEM) images of the dentin specimens were obtained prior to any treatment, after the application of the therapeutic agents and after acid challenge and mean tubule occlusion scores were recorded in each case employing a suitable scoring system. The statistical analysis employed One-way ANOVA test followed by Tukey's Post hoc test and Student Paired t-test for intergroup and intragroup comparisons of the mean tubule occlusion scores respectively.

Results

Group 2, treated with ozonated oil alone showed a statistically significant increase in the number of open dentinal tubules. Group 4 showed more compact deposits of desensitizing agent and more densely occluded tubules as compared to Group 3 which was more retained in the former even after acid challenge.

Conclusion

Adjunctive application of the desensitizing agent containing arginine, with ozonated oil has a synergistic effect, where the latter causes opening of dentinal tubules allowing more compact penetration of the former and thus may be a potentially more effective treatment approach in the management of DH.

Effectiveness of fluoride varnish, diode laser, and their combination in treatment of dentin hypersensitivity: A randomized split-mouth clinical trial

Background:

Dentin hypersensitivity is a common dental problem with no permanent cure and predictable prognosis.

Aim:

The aim of this study was to evaluate the effectiveness of fluoride varnish (sodium fluoride [NaF]), diode laser, and the combination of NaF and diode laser in the treatment of dentin hypersensitivity.

Settings and Design:

This was a randomized split-mouth clinical trial.

Materials and Methods:

Sixty patients aged 20–60 years suffering from dentin hypersensitivity to air-blast, cold, and tactile stimulation corresponding to 4 cm and above on the Visual Analog Scale (VAS) in three quadrants with at least two hypersensitive teeth per quadrant were selected. Hypersensitive teeth were allotted to Group 1 – 5% NaF varnish application alone, Group 2 – 810-nm gallium–aluminum–arsenide laser (GaAlAs) diode laser (0.5 W) irradiation alone, and Group 3 – NaF varnish application, followed by diode laser irradiation. VAS score was recorded at baseline, 1 week, 2 weeks, 1 month, 3 months, and 6 months.

Results:

A statistically significant reduction in dentin hypersensitivity was observed in all the three groups, from the baseline to the 1^st-, 3^rd-, and 6^th-month follow-ups (P < 0.05). Group 2 and Group 3 demonstrated a significantly higher reduction (P < 0.05) in dentin hypersensitivity for all the stimuli as opposed to Group 1 at all follow-up intervals. However, no statistically significant difference (P > 0.05) was present between Group 2 and Group 3 at all follow-ups.

Conclusion:

Diode laser is significantly more effective than fluoride varnish alone in the treatment of dentin hypersensitivity over a period of 6 months.

Effectiveness of diode laser and fluoride on dentin hypersensitivity treatment: A randomized single-blinded clinical trial

Background:

This randomized single-blinded clinical trial aimed to evaluate the effectiveness of diode laser and fluoride in the treatment of dentin hypersensitivity (DH) due to gingival recession.

Materials and Methods:

Twenty-eight individuals randomly distributed across three groups participated: 10 individuals who were treated with diode laser, nine who were treated with fluoride, and nine who received placebo. Pain was assessed with the Visual analog scale (VAS). Evaporative stimulus and tactile stimulus were evaluated with the verbal rating scale (VRS). VAS was applied shortly after, 6 h after, 12 h after, and 24 h after the single-session treatment for DH, whereas VRS was applied shortly after, 15 min and 7 days after the treatment. Participants' quality of life was assessed with the validated Brazilian version of the Dentine Hypersensitivity Experience Questionnaire assessing functional limitations, coping behaviors, emotional, and social impacts caused by DH. Descriptive statistics and the ANOVA test were used. Values of P < 0.05 were statistically significant.

Results:

Diode laser significantly reduced the DH to the evaporative stimulus (P = 0.002). The application of fluoride did not change the degree of DH to evaporative and tactile stimuli (P > 0.05). The group of individuals who were treated with diode laser presented a higher reduction in DH (25.4%) when compared to the group of individuals treated with fluoride (17.1%), and the group of individuals among whom placebo had been used (2.9%). Descriptive analysis indicated that the items measuring the emotional and social impacts of DH were those with a more negative impact on the individuals.

Conclusion:

Therapy with diode laser was more effective in reducing DH than therapy with fluoride.

Crystal growth in dentinal tubules with bio-calcium carbonate-silica sourced from equisetum grass

BACKGROUND/PURPOSE

One effective way to deal with dentin hypersensitivity is to develop materials to seal the tubules. The porous bio-calcium carbonate-silica (BCCS) contained well-dispersed CaCO₃ would form calcium phosphates to seal the dentinal tubules when mixed with an acidic solution. The acidic hydrothermal treatment and calcination to isolate the BCCS from the agricultural waste like equisetum grass was used, which would be more environmentally friendly than chemically synthesized mesoporous biomaterials. The aim of this study was to develop mesoporous materials from natural resources to occlude the dentinal tubules which could be more environmentally-friendly.

METHODS

Dentin disc samples were prepared and treated with different methods as follows: (1) BCCS mixed with H₃PO₄; (2) BCCS mixed with KH₂PO₄; (3) Seal & Protect® was used as a comparison group. Sealing efficacy was evaluated by measuring the depths and percentages of precipitate occlusion in dentinal tubules with SEM.

RESULTS

The N₂ adsorption-desorption isotherm of the BCCS demonstrated a pore size of around 15.0 nm and a surface area of 61 m²g-1. From the results of occlusion percentage and depth, the BCCS treated with H₃PO₄ or KH₂PO₄ demonstrated promising sealing efficacy than the commercial product.

CONCLUSION

This synthetic process used the agricultural waste equisetum grass to produce bio-calcium carbonate-silica would be environmentally friendly, which has great potential in treating exposed dentin related diseases.

Prior Application of 10% Potassium Nitrate to Reduce Postbleaching Sensitivity: A Randomized Triple-Blind Clinical Trial

OBJECTIVE

To evaluate if the topical application of 10% potassium nitrate applied before in-office bleaching is effective to reduce the risk and intensity of tooth sensitivity (TS), as well as to evaluate if its application can jeopardize color change.

MATERIALS AND METHODS

A randomized, split-mouth triple-blind clinical trial was conducted on 43 young patients with incisors A2 or darker. Half of the patient's upper arch received either the application of a 10% potassium nitrate or placebo gel for 10 min in a university setting. In-office bleaching was performed in three 15-min applications in two clinical sessions (1-week interval) using 35% hydrogen peroxide. Risk and intensity of TS was recorded with a 0-4 Numeric Rating Scale and a 0-10 Visual Analogue Scale during bleaching, 1 hour, 24 hours, and 48 hours after bleaching. Color was evaluated before and 1 month after bleaching with shade guides (Vita Classical and Vita Bleachedguide) and a spectrophotometer. The risk of TS (McNemar's test) and intensity of TS (Wilcoxon signed-rank for Numeric Rating Scale and paired t-test for Visual Analogue Scale) were statistically evaluated. Color change was compared using paired t-test. Significant level was set at 5%.

RESULTS

No significant difference was observed in the absolute risks of TS between groups (RR = 1.11; 95% CI 0.97 to 1.27; P = .12), which exceeded 87% for both groups. Similarly, no difference in TS intensities was detected (P > .05). Significant whitening was observed with all color measurement instruments with no difference between groups (P > .05).

CONCLUSION

The topical application of 10% potassium nitrate, before in-office bleaching, did not reduce the risk and intensity of TS and did not jeopardize color change.

Dentin Tubule Occlusion Potential of Novel Dentifrices Having Fluoride Containing Bioactive Glass and Zinc Oxide Nanoparticles

OBJECTIVE

To compare the in vitro potential of dentin tubule occlusion of two novel experimental dentifrices consisting of fluoride containing bioactive glass (BG) with zinc oxide nanoparticles.

MATERIALS AND METHODS

Forty-eight dentin discs (n = 48) were divided into 6 groups (n = 8), based on their brushing dentifrices: Group 1 = artificial saliva (AS; control); Group 2 = fluoride dentifrice (Colgate Palmolive©, UK); Group 3 = experimental nonactive agent dentifrice; Group 4 = experimental dentifrice with 1.5% BG; Group 5 = experimental dentifrice with 4% BG; and Group 6 = BioMinF© dentifrice. Postbrushing, the discs were subjected to acidic challenge with 6% wt citric acid (pH = 4.0) for 1 min. Scanning electron microscope (SEM) and energy-dispersive X-ray (EDX) spectroscopy were performed pre- and post-citric acid challenges, and percentages of tubule occlusion assessed.

RESULTS

SEM micrographs of group 1 (AS) show no tubule occlusion (0%), whereas those of groups 2 and 3 show partial tubule occlusion (25 to <50% of tubules occluded). The SEM micrographs of dentifrices containing fluoride-BG (groups 4, 5, and 6) show that most of the tubules (>50 and <100%) were occluded. For all the groups (excluding group 1), pre- and post-citric acid challenge values are statistically significant (p < 0.05). EDX analysis reveals the presence of zinc in experimental dentifrices only.

CONCLUSION

The results of novel experimental dentifrices are comparable to those of the BioMinF©, in terms of tubule occlusion. Dentifrices containing BG could serve as an alternative in dentin sensitivity management.

Fabrication of calcium phosphate composite polymer/SLS-stabilized emulsion-based bioactive gels and their application for dentine tubule occlusion

OBJECTIVES

Calcium phosphate/SLS/P123 composite bioactive gels were prepared to achieve dentine tubule occlusion.

METHODS

Gels containing calcium phosphate particles were prepared in a water-in-oil microemulsion system with a mixture of triblock copolymer pluronic (P123) as a co-surfactant and sodium lauryl sulfate (SLS) as a surfactant in cyclohexane. Subsequently, calcium chloride dihydrate and sodium hydrogen phosphate aqueous solutions were added in a water phase. Finally, slow evaporation of the oil phase at room temperature was performed to produce a hybrid gel. The obtained gels were investigated for their toxicity by the sulforhodamine B (SRB) assay and applied on human dentine specimens to examine their ability to occlude dentine tubules.

RESULTS

The size and morphology of the calcium phosphate particles embedded in the gel depended on the concentration of P123 and SLS, which were used as a template for mineral precipitation. The prepared calcium phosphate particles (200-500 nm in diameter) with the maximum polymer and surfactant content exhibited spherical shapes. Further, on reducing their content twice and tenfold yields micro-particles with flower-like shapes. These bioactive gels were able to occlude into dentine tubules after 3 days of application with a plugging rate of 79.22% when using the smallest particles. In addition, calcium phosphate nanorods were transformed into dentine tubules with a maximum depth of 6 μm on increasing the amount of gel.

CONCLUSIONS

The bioactive gels were effectively used as bioactive fillers to occlude exposed human dentine tubules.

Dentin tubule obturation of a bioglass-based dentin desensitizer under repeated exposure to lactid acid and brushing

Background

Dentin hypersensitivity is a frequent finding especially in periodontitis patients. Conventional treatment aims for obstruction of dentin tubules by disabling liquid and osmotic fluctuation to and from the pulpal chamber. A novel bioglass-based desensitizer was shown to obstruct tubules and to resist periodic exposure to lactic acid. Whether this obstruction is resistant to brushing had not been tested so far. Accordingly, the present study aimed to assess dentin tubule obstruction after repeated acid exposure and brushing.

Methods

Sixty dentin discs were cleaned with 17% EDTA, mounted into a pulp fluid simulator and randomly divided into 3 groups: No surface treatment in Group A, Seal&Protect® in group B and DentinoCer in group C. Discs were exposed to 0.1 M non-saturated lactic acid thrice and standardized brushing twice a day for 12 days. At baseline and after 2, 4 and 12 d samples were removed from the setting and prepared for top-view SEM analysis to assess tubule obstruction using the Olley score. Discs were then vertically cut and the section surface morphologically assessed using backscatter imaging. For both vertical and sectional surfaces EDX analysis was used to characterize the surface composition in the tubular and inter-tubular area.

Results

Group A showed clean tubular lumina at all time points. From day 2 onwards dentin showed exposed collagen fibers. Group 2 initially showed a complete surface coverage that flattened out during treatment without ever exposing tubules. At baseline, samples of Group C displayed a complete homogeneous coverage. From day 2 on tubules entrances with obstructed lumen became visible. While on day 4 and 12 the dentin surface exposed collagen fibers the lumina remained closed. EDX analysis of the vertical and horizontal views showed that P and Ca were predominant elements in both the inter- and tubular dentin while Si peaks were found in the tubule plugs.

Conclusion

While group B displayed a packed layer on the surface during the whole investigation time group C samples lost their superficial layer within 48 h. Tubule plugs containing considerable Si proportions indicated previous presence of DentinoCer, while high Ca and P proportions suggest obturation by dentin-like material.

Impact of toothpaste on oral health-related quality of life in people with dentine hypersensitivity

BACKGROUND

Dentine hypersensitivity can impact functional status and everyday activities such as eating and talking. This study aimed to assess changes in oral health-related quality of life measures in individuals with dentine hypersensitivity following long-term use (24 weeks) of a commercially available toothpaste marketed for dentine hypersensitivity relief.

METHODS

This study was conducted across two sites and enrolled 75 adults with ≥2 non-adjacent sensitive teeth. Participants were assigned to twice-daily brushing with toothpaste containing 0.454% w/w stannous fluoride (1100 ppm fluoride). Every 4 weeks, participant-reported outcomes were assessed using the Dentine Hypersensitivity Experience Questionnaire (DHEQ), a condition specific oral health-related quality of life scale that has five domains and includes questions on social and emotional impact, restrictions, adaptations and effect on life overall. Responses to a clinically applied evaporative (air) stimulus were assessed using the examiner-observed Schiff sensitivity scale and Labelled Magnitude Scales (LMS), which included dentine hypersensitivity-specific descriptors of intensity, duration, tolerability and descriptive qualities of the participant's response.

RESULTS

Participant-reported outcomes demonstrated reduction of the impact of dentine hypersensitivity over time on health-related quality of life, as measured by the DHEQ. This reached statistical significance from Week 8 onwards (p < 0.0001 versus baseline) for the Total DHEQ score, with scores continually decreasing at each timepoint. Most domain scores followed a similar pattern. Statistically significant reductions were also detected for the examiner-observed Schiff Sensitivity Scale scores at all timepoints (including at 4 weeks) (p < 0.05), which were mirrored by LMS responses. The toothpaste was generally well-tolerated.

CONCLUSIONS

These results show that long-term use of a sensitivity toothpaste containing 0.454% w/w stannous fluoride has a beneficial, ongoing, impact on the oral health-related quality of life of people with dentine hypersensitivity.

TRIAL REGISTRATION

This study was registered at Clinicaltrials.gov ( https://clinicaltrials.gov/ct2/show/NCT02752958 ) on April 27, 2016.

Are combined bleaching techniques better than their sole application? A systematic review and meta-analysis

OBJECTIVES

A systematic review and meta-analysis were performed to answer this research question: "Does combined in-office (IO) and at-home (AH) bleaching produce improved color change and lower tooth sensitivity (TS) better than solely AH or IO bleaching in adults?"

MATERIAL AND METHODS

Randomized controlled trials in adults that compared combined versus sole application bleaching were included. The risk of bias (RoB) was evaluated using the Cochrane Collaboration tool. Meta-analyses were conducted for color change in shade guide units (∆SGU) and with a spectrophotometer (∆E*), risk, and intensity of TS, using the random effects model. Heterogeneity was assessed with Cochran's Q test and I² statistics. GRADE assessed the quality of the evidence. PubMed, Scopus, Web of Science, LILACS, BBO, Cochrane Library, SIGLE, IADR abstracts, unpublished, ongoing trial registries, dissertations, and theses were searched on August 28, 2017 (updated on January 29, 2019).

RESULTS

Twelve studies remained. Two were considered to have low RoB. For combined vs. IO bleaching, no significant difference for ∆E*, ∆SGU, and risk of TS were observed; data were not available to analyze the intensity of TS. For combined vs. AH bleaching, no significant difference for ∆E*, ∆SGU, but lower TS to risk (RR 1.40, 95% 1.10 to 1.80) and intensity (MD 1.40, 95% CI 0.18 to 2.63) were detected for AH bleaching. Quality of evidence was graded as low or very low in all meta-analyses.

CONCLUSION

Lower risk and intensity of TS was observed for the solely AH group without jeopardizing color change. However, more studies are still encouraged due to the low quality of evidence for most of the outcomes.

CLINICAL RELEVANCE

If clinicians are to choose between combined or sole AH bleaching, the solely AH may be preferable; combined bleaching may potentiate the risk of TS without benefits in color change. For combined or sole IO bleaching, no important clinical difference in color change and risk of TS were detected; however, intensity of TS could not be compared due to lack of data. Further studies should be conducted due to the low/very low quality of the evidence.

Effect of artificial saliva on permeability of dentin treated with phosphate containing desensitizer measured by digital flow meter

The aim of this study was to investigate the effects of artificial saliva on permeability measured using a highly sensitive digital flow meter of dentin discs treated with a phosphate containing desensitizer compound (Teethmate desensitizer; TD). Four random groups (n=10) were treated either with TD or distilled water (DW), then stored in artificial saliva (AS) or DW for 1 day, 1 week and 1 month. Flow rates under 2 kPa pressure were calculated as percentage reduction (PR%) from the baseline. The PR% of TD/AS group was significantly lower after 1 day and 1 week, but the PR%s of 1 month groups among TD/AS, TD/DW and DW/AS were not significantly different. The SEM photograph of TD/AS group displayed that the dentin surface was densely covered with mineral deposits. Ca and phosphate ions from the artificial saliva could penetrate into the tubules and precipitate as hydroxyapatite, resulting in the reduction in permeability.

Limited Evidence Suggests That Many Types of Desensitizing Toothpaste May Reduce Dentin Hypersensitivity, but Not the Ones With Strontium or Amorphous Calcium Phosphate

ARTICLE TITLE AND BIBLIOGRAPHIC INFORMATION

Effect of desensitizing toothpastes on dentine hypersensitivity: A systematic review and meta-analysis. Hu M-L, Zheng G, Zhang Y-D, Yan X, Li X-C, Lin H. J Dent (2018)75:12-21.

SOURCE OF FUNDING

The authors reported that this research did not receive any specific funding from the public, commercial, or not-for-profit sectors.

TYPE OF STUDY/DESIGN

Systematic review with meta-analysis of data.

Prevalence of Dentinal Hypersensitivity and Dental Erosion among Competitive Swimmers, Kerala, India

Background

Professional swimmers face a hidden occupational hazard due to improper maintenance of pool. Ill maintained pools can lead to erosive effects on dental health and thus needs to be evaluated.

Methodology

Fifty-six competitive swimmers from two training centers were contacted and surveyed for swimming exposure and oral health. A visual analog scale was used to rate the tooth sensitivity. Dental erosion and dental caries were recorded according to WHO oral health assessment criteria (2013). The dentinal hypersensitivity experience was assessed using the dentine hypersensitivity experience questionnaire - 15 (DHEQ-15). Data were analyzed using Chi-square test and multivariate analysis.

Results

The prevalence of dentinal hypersensitivity and dental erosion was found to be 69.6% and 48.2%, respectively. The common surfaces affected by dental erosion were palatal surfaces of maxillary anterior, followed by lingual surfaces of mandibular anterior. There was a direct association between duration of the stay in pool and dental erosion. The DHEQ-15 questionnaire revealed that more than 80% of the participants never felt these sensations had any serious long-term effects on oral health.

Conclusions

Oral health professional must understand dental erosion among competitive swimmers as an occupational oral health hazard and provide early counseling and necessary invasive and noninvasive care.

Diazepam as attenuator of pain induced by dentin hypersensitivity in rats exposed to stress

The pain in dentin hypersensitivity (DH) has distinct sensory and emotional origins, with variations that occur in different intensities for each individual. The aim of this study is to evaluate the effects of diazepam in the attenuation of the pain induced by DH.

DESIGN

Fifty male Wistar rats were divided into five groups: control group received water ad libitum (C); stress group received water ad libitum plus stress (S); DH induced by erosion challenge with isotonic solution ad libitum (G); DH and stress (GS); and DH, stress and diazepam (GSD) groups. Animals of the GS group were exposed to the New York Subway Stress Model. Animals treated with diazepam (GSD group) received 1 mg/kg every 3 days, from the 15th day of treatment until the end of the stress-inducing period. The body weights of rats were weekly registered. After 30 days, all groups were submitted to the DH test, which was assessed using cold water stimuli, and were graded 0, 0.5, 1, 2, or 3. Dental elements were evaluated using scanning electron microscopy (SEM).

RESULTS

1) Groups G and GS presented the highest DH scores, which confirms that stress increased pain response; 2) GSD group had significantly reduced DH scores compared to G and GS groups; 3) SEM of dental elements showed exposed dentin tubules in G, GS, and GSD groups, as expected.

CONCLUSIONS

diazepam attenuated pain induced by dentin hypersensitivity in rats exposed to stress.

Evaluation of the effects of Er:YAG laser, Nd:YAG laser, and two different desensitizers on dentin permeability: in vitro study

The purpose of this in vitro study was to evaluate and compare the efficacy of erbium-doped yttrium aluminum garnet (Er:YAG) laser, neodymium-doped yttrium aluminum garnet (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 (2940 nm; 0.2 W, 80 mJ/pulse, 3 Hz); Nd:YAG laser-treated (1064 nm; 1 W, 10 Hz); 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 data were analyzed using the Wilcoxon, paired-samples t, Kruskal-Wallis, and Mann-Whitney U tests. 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 (p < 0.05). Among the groups, we detected a significant difference in only when comparing the Er:YAG laser- and NPP-treated groups (p = 0.034). SEM analysis revealed physical changes in the dentin surface in all groups. This in vitro study shows that all tested desensitizers and laser treatments 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. In addition, clinical and laboratory studies should be performed for this product, and their efficacy should be assessed by combined therapy with lasers.

Tooth sensitivity with a desensitizing-containing at-home bleaching gel-a randomized triple-blind clinical trial

OBJECTIVES

Desensitizing agents are usually included in the composition of bleaching agents to reduce bleaching-induced tooth sensitivity (TS). This randomized clinical trial (RCT) evaluated the risk and intensity of TS and color change after at-home bleaching with a desensitizing-containing (3% potassium nitrate and 0.2% sodium fluoride) and desensitizing-free 10% carbamide peroxide (CP) gel (Whiteness Perfect, FGM).

METHODS

A triple-blind, within-person RCT was conducted on 60 caries-free adult patients. Each participant used the gel in a bleaching tray for 3 h daily for 21 days in both the upper and lower dental arches. The absolute risk and intensity of TS were assessed daily through the 0-10 VAS and NRS scale for 21 days. Color change was recorded using shade guides (Vita Classical and Vita Bleachedguide) and the Easyshade spectrophotometer at baseline, weekly and 30 days after the end of the bleaching. The risk and intensity of TS were evaluated by the McNemar and Wilcoxon Signed Rank tests, respectively. Color change (ΔSGU and ΔE) were evaluated by the Mann-Whitney test and a paired t-test, respectively (α = 0.05).

RESULTS

No difference in the TS and color change was observed (p > 0.05).

CONCLUSIONS

The incorporation of potassium nitrate and sodium fluoride in 10% carbamide peroxide at-home bleaching gel tested in this study did not reduce the TS and did not affect color change (RBR-4M6YR2).

Effect of topical application of dipyrone on dental sensitivity reduction after in-office dental bleaching: A randomized, triple-blind multicenter clinical trial

BACKGROUND

Tooth sensitivity commonly occurs during and immediately after dental bleaching. The authors conducted a trial to compare tooth sensitivity after in-office bleaching after the use of either a topical dipyrone or placebo gel.

METHODS

A split-mouth, triple-blind, randomized, multicenter clinical trial was conducted among 120 healthy adults having teeth that were shade A2 or darker. The facial tooth surfaces of the right or left sides of the maxillary arch of each patient were randomly assigned to receive either topical dipyrone or placebo gel before 2 in-office bleaching sessions (35% hydrogen peroxide) separated by 2 weeks. Visual analog and numerical rating scales were used to record tooth sensitivity during and up to 48 hours after bleaching. Tooth color change from baseline to 1 month after bleaching was measured with shade guide and spectrophotometer measures. The primary outcome variable was absolute risk of tooth sensitivity. An intention-to-treat analysis was used to analyze data from all patients who were randomly assigned to receive the dipyrone and placebo gels.

RESULTS

No statically significant difference was found in the absolute risk of tooth sensitivity between the dipyrone and placebo gels (83% and 90%, respectively, P = .09; relative risk, 0.92; 95% confidence interval, 0.8 to 1.0). A whitening effect was observed in both groups with no statistically significant difference (P > .05) between them. No adverse effects were observed.

CONCLUSION

Topical use of dipyrone gel before tooth bleaching, at the levels used in this study, did not reduce the risk or intensity of bleaching-induced tooth sensitivity.

PRACTICAL IMPLICATIONS

Topical application of dipyrone gel does not reduce bleaching-induced tooth sensitivity.

Molecular basis of dental sensitivity: The odontoblasts are multisensory cells and express multifunctional ion channels

Odontoblasts are the dental pulp cells responsible for the formation of dentin. In addition, accumulating data strongly suggest that they can also function as sensory cells that mediate the early steps of mechanical, thermic, and chemical dental sensitivity. This assumption is based on the expression of different families of ion channels involved in various modalities of sensitivity and the release of putative neurotransmitters in response to odontoblast stimulation which are able to act on pulp sensory nerve fibers. This review updates the current knowledge on the expression of transient-potential receptor ion channels and acid-sensing ion channels in odontoblasts, nerve fibers innervating them and trigeminal sensory neurons, as well as in pulp cells. Moreover, the innervation of the odontoblasts and the interrelationship been odontoblasts and nerve fibers mediated by neurotransmitters was also revisited. These data might provide the basis for novel therapeutic approaches for the treatment of dentin sensibility and/or dental pain.

[Effect of a nano hydroxyapatite desensitizing paste application on dentin bond strength of three self-etch adhesive systems]

Objective: To evaluate a nano-hydroxyapatite (nano-HA) desensitizing paste application on the bond strength of three self-etch adhesives. Methods: Three dentin specimens of about 1 mm thick were cut from two teeth. Scanning electron microscope (SEM) was used to evaluate the dentin surfaces without treatment, after citric acid treatment and after nano-HA treatment. Thirty-six intact third molars extracted for surgical reasons were cut to remove the occlusal enamel with isomet, and then were etched with 1% citric acid for 20 s to simulate the sensitive dentin and divided into two groups randomly using a table of random numbers (n=18): the control group (no treatment) and the HA treated group (with nano-HA paste treatment). Each group was divided into three subgroups randomly using a table of random numbers (n=6). Subgroup A, B and C was bonded with G-Bond, Clearfil S(3) Bond and FL-Bond Ⅱ according to the manufacture's instruction separately. At 24 h after bonding procedure, and after water storage for 6 months, microtensile bond strength of the specimens was tested and the failure mode was analyzed. Results: SEM obeservation showed that citric acid could open the dentin tubules to set up the sensitive dentin model, and the nano-HA could occlude the dentin tubules effectively. For subgroup A, bonding strength of specimens treated with nano-HA ([41.14±8.91] MPa) was significantly high than that of the control group ([34.27±6.16] MPa) at 24 h after bonding procedure (P<0.05). However, after 6 month water ageing, the bonding strength of the control group and the HA treated group showed no significant difference (P>0.05). For subgroup B, specimens with nano-HA application showed lower bonding strength ([30.87±6.41] MPa) than that of the control group ([36.73±5.82] MPa) at 24 h after bonding procedure (P<0.05), and after 6 month water ageing, the bond strength of nano-HA application ([25.73±6.99] MPa) was also lower than that of the control group ([32.33±5.08] MPa) (P<0.05). For subgroup C, the bond strength of the control group and the HA treated group have no significant difference either before or after 6 month water ageing (P>0.05). Failure mode analysis showed that more than half of the samples in all groups were adhesive failure. Conclusions: Nano-HA treatment decreased the bond strength of subgroup B, while had no adverse effect on subgroup A and subgroup C.

Evaluation of Five Different Desensitizers: A Comparative Dentin Permeability and SEM Investigation In Vitro

BACKGROUND/OBJECTIVE

The purpose of this study was to evaluate the efficacy and durability of five different dentin desensitizers (Gluma Desensitizer Powergel, Bifluorid 12, Gluma Self Etch Bond, D/Sense Crystal, Nupro Sensodyne Prophylaxis Paste with Novamin) on tubule occlusion and dentin permeability reduction in vitro.

METHOD

The quantitative changes in permeability of 100 dentin discs were measured after desensitizer treatments and following post-treatments of 6% citric acid challenge for 1 min or immersion in artificial saliva for 24 hours under hydrostatic pressure generated by a computerised fluid filtration meter. Qualitative SEM analyses were also carried out.

RESULTS

Dentin permeability decreased after desensitizer application in all groups. Nevertheless, only the difference between 'Gluma Self Etch Bond' and 'Nupro Sensodyne Prophylaxis Paste with Novamin' groups was significantly different (p<0.05). Dentin permeability increased significantly after post-treatments (p<0.05). There was no statistically difference among the citric acid-subgroups (p>0.05). Of all the artificial saliva-subgroups, only the difference between 'D/Sense Crystal' and 'Bifluorid 12' was significantly different (p<0.05). In SEM analysis, morphological changes were detected on the dentin surface and within the tubules following desensitizer treatments and post-treatments.

CONCLUSION

All the desensitizers significantly reduced dentin permeability by changing the morphology of the dentin surface and/or dentinal tubules. Following post-treatments, there was some reduction in the efficacy of the desensitizers which was represented by the reduction in permeability values. SEM analysis revealed some physical changes in the dentin structure which can partly give an explanation to the reduced efficacy of tested desensitizers.

Complete Coverage of a Class III (RT2) Gingival Recession With the Combination of a Free Subepithelial Connective Tissue Graft and a Laterally Positioned Flap

INTRODUCTION

Gingival recession (GR) presents a major concern for patients, especially when associated with tooth sensitivity or esthetic concerns.

CASE PRESENTATION

This report describes the complete coverage of a Class III GR with the combination of a free subepithelial connective tissue graft and a laterally positioned flap. After treatment for GR of the mandibular right canine with 12 mm of clinical attachment loss, there was complete coverage and an increase in keratinized gingiva.

CONCLUSION

A promising technique is presented that yielded 100% defect coverage and gingival tissue enhancement.

Predictive factors on the efficacy and risk/intensity of tooth sensitivity of dental bleaching: A multi regression and logistic analysis

OBJECTIVES

The aim of this study was to identify predictor factors associated with the whitening outcome and risk and intensity of bleaching-induced tooth sensitivity from pooled data of 11 clinical trials of dental bleaching performed by the same research group.

METHODS

The individual patient data of several published and ongoing studies about dental bleaching was collected and retrospectively analyzed. At the patient-level, independent variables (bleaching techniques [at-home and in-office protocols], sex, age and baseline tooth color in shade guide unit [SGU]) as well as dependent variables (color change in shade guide units (ΔSGU), color change in the CIEL*a*b* system (ΔE), risk and intensity of TS in a visual analog scale) were collected. Multivariable linear regression and multivariable logistic regression models were carried out using backward elimination whenever the p-values were higher than 0.05.

RESULTS

A significant relationship between baseline color and age on color change estimates was detected (p<0.001). Every increase of one SGU in the baseline color resulted in an increase of approximate 0.66 in the final ΔSGU and 2.48 for the ΔE. For every increase of one year in the participant's age we observed a decrease of the whitening degree of 0.07 for the final ΔSGU and 0.69 for the ΔE. The bleaching technique was shown to be a significant predictor of ΔSGU (p<0.001) but not of ΔE. In regard to TS, baseline color and bleaching technique are significant predictors (p<0.001). The risk of TS for at-home bleaching was 51% (95% CI 41.4-60.6) and for the in-office 62.9% (95% CI 56.9-67.3).

CONCLUSIONS

Younger patients with darker teeth reach a higher degree of whitening. Patient with darker teeth and submitted to at-home bleaching presents lower risk and intensity of TS.

CLINICAL SIGNIFICANCE

The baseline color of the teeth and the patient's age is directly related to the effectiveness of dental bleaching and TS.

Prevalence of dentinal hypersensitivity and study of associated factors: a cross-sectional study based on the general dental population of Davangere, Karnataka, India

BACKGROUND

Dentin hypersensitivity (DH) is a common clinical finding with a wide variation in prevalence and aetiological factors. The aim of this cross-sectional study was to determine the prevalence and examine some associated aetiological factors of DH in a study of an Indian population residing in and around Davangere district of Karnataka.

MATERIAL AND METHODS

A total of 404 patients (3,859 teeth) were examined for the presence of DH by means of a questionnaire and intraoral tests (air and tactile stimuli). Plaque, gingival recession, abrasion/erosion, labioversion and toothbrushing habits were noted.

RESULTS

A total of 795 teeth, in 404 patients, were diagnosed as having DH, giving an overall prevalence figure for DH of 20.6%. The chi-square test and the Z-test values for proportions were used to evaluate statistical correlations. The 36-45 years' age group was the cohort with the highest number of subjects with DH, and female subjects had greater predilection for DH compared with male subjects. Incisors were the tooth type most affected. DH was significantly correlated with gingival recession, labioversion and abrasion/erosion (P<0.05). Both gingival recession and abrasion/erosion were significantly correlated with brushing once daily in a horizontal direction and use of a toothbrush with medium-hardness bristles (P<0.05).

CONCLUSION

The prevalence of DH in the Indian population is 20.6%, with a higher predilection for DH in the age cohort 36-45 years and in female subjects. DH is a multifactorial entity with several aetiological factors, making its diagnosis and treatment a challenge for the clinician.

Pre- and postoperative dexamethasone does not reduce bleaching-induced tooth sensitivity: A randomized, triple-masked clinical trial

BACKGROUND

Tooth sensitivity (TS) is the most common side effect of dental bleaching therapies. Dexamethasone has been used with tooth bleaching to reduce TS. The efficacy of dexamethasone for this purpose has not been well studied.

METHODS

The authors conducted a triple-masked, randomized, clinical trial with a parallel design involving 63 healthy participants who received either a placebo or dexamethasone. The placebo or dexamethasone (8 milligrams) was administered 1 hour before the in-office bleaching (35% hydrogen peroxide) and extra doses of 4 mg were administered every 6 hours for a total of 48 hours. TS was recorded on 2 scales: visual analog scale (0-10) and numeric rating scale (0-4) in different periods. The color evaluations were performed before and 1 month after dental bleaching with visual shade guides VITA Classical (VITA Zahnfabrik) and VITA Bleachedguide 3D-MASTER (VITA Zahnfabrik), and for a shade guide evaluation, the authors used a digital spectrophotometer, VITA Easyshade (VITA Zahnfabrik). The absolute risk of TS was evaluated by a Fisher exact test. Data of TS intensity using the NRS scale for the 2 groups were compared with Mann-Whitney and Friedman tests, whereas data from the visual analog scale were evaluated by 2-way repeated measures analysis of variance. The color changes between groups were compared using a t test (α = .05).

RESULTS

In both groups, the authors detected a high risk of TS, which was approximately 90%. No significant difference was observed in terms of TS intensity. A whitening of approximately 3 shade guide units of the VITA Classical was detected in both groups, which were statistically similar.

CONCLUSIONS

The use of dexamethasone before bleaching did not reduce the risk and intensity of bleaching-induced TS.

PRACTICAL IMPLICATIONS

The use of the steroidal anti-inflammatory agent dexamethasone was not capable of preventing TS arising from in-office dental bleaching.

Dentin hypersensitivity induces anxiety and increases corticosterone serum levels in rats

AIMS

Investigate the relationships between experimentally induced dentin hypersensitivity (DH) with behavioral, endocrine and dentin erosion data.

METHODS

Male Wistar rats divided into four groups, two controls and two experimental, received tap water or isotonic solution (Gatorade®, lemon, pH2.7) for 30 or 45 days. The DH test was performed by a cold water stimulus on molars. A score (0-3) was given to the rats' pain response. Anxiety was evaluated by the elevated plus maze model and by serum corticosterone levels. The dentin erosion was observed by scanning electron microscopy (SEM). Anatomopathological studies were performed on the stomach, adrenal, kidney, and liver.

RESULTS

Relative to control groups, experimental rats showed: 1) increased hypersensitivity scores (control group, 0; experimental groups, 2 (limits 0.5-3) on the 30th day and 2 (limits 1-3) on the 45th day); 2) reduced percentage of time and entries in the open arms and in serum corticosterone levels; 3) totally exposed dentinal tubules on the 30th day in SEM analysis of the teeth; and 4) no alterations in the anatomopathological and histological evaluations.

CONCLUSIONS

The treatment with isotonic solution for 30 days was able to induce DH after erosive challenge and severe DH was observed after isotonic solution treatment for 45 days. The pain induced by cold stimuli was consistent with the grade of DH. The close relationships between dental erosion, response to pain, serum levels of corticosterone and the EPM behavior responses reveal the effects of DH at several levels.

Comparative evaluation of NovaMin desensitizer and Gluma desensitizer on dentinal tubule occlusion: a scanning electron microscopic study

Purpose

In this study, the effect of calcium sodium phosphosilicate (NovaMin) desensitizing agent, which is a powder-based system, and hydroxyethyl methacrylate and glutaraldehyde (Gluma desensitizer), which is liquid-based system, on dentinal tubule occlusion was analyzed by scanning electron microscope. The effects of the above two along with one control group were compared to determine the more effective method of sealing the dentinal tubules after initial application.

Methods

Twenty specimens were allocated to each of 3 groups: Control, Gluma desensitizer, and NovaMin. Two additional samples were also prepared and treated with Gluma and NovaMin; these samples were longitudinally fractured. The specimens were prepared from extracted sound human premolars and were stored in 10% formalin at room temperature. The teeth were cleaned of gross debris and then sectioned to provide one to two dentin specimens. The dentin specimens were etched with 6% citric acid for 2 minutes and rinsed in distilled water. Control discs were dried, and the test discs were treated with the desensitizing agents as per the manufacturer's instructions. The discs as well as longitudinal sections were later analyzed under the scanning electron microscope. The proportions of completely occluded, partially occluded, and open tubules within each group were calculated. The ratios of completely and partially occluded tubules to the total tubules for all the groups was determined, and the data was statistically analyzed using nonparametric tests and statistical significance was calculated.

Results

NovaMin showed more completely occluded tubules (0.545±0.051) while Gluma desensitizer showed more partially occluded tubules (0.532±0.075). The differences among all the groups were statistically significant (P≤ 0.05).

Conclusion

Both materials were effective in occluding dentinal tubules but NovaMin appeared more promising in occluding tubules completely after initial application.