Efficacy of splint therapy for the management of temporomandibular disorders: a meta-analysis.

Temporomandibular disorders (TMD) are a group of clinical problems affecting temporomandibular joint (TMJ), myofascial muscles and other related structures. Splint therapy is the most commonly used approach to treatment of TMD, but its effectiveness is remains unclear. We therefore conducted a meta-analysis to evaluate the effectiveness of splint therapy for TMD in adults. The electronic databases PubMed, EMBASE, Cochrane Library, and ClinicalTrials.gov were searched for reports published up to March 31, 2016. Thirteen eligible studies involving 538 patients were identified. The results indicated that splint therapy increased maximal mouth opening (MMO) for patients with a MMO <45mm and reduced pain intensity measured using the visual analogue scale (VAS) for patients with TMD without specific description (TMDSD). Splint therapy also reduced the frequency of painful episodes for patients with TMJ clicking. No publication bias was observed, as determined with Egger's test for all outcomes. On the basis of this evidence, we recommend the use of splints for the treatment and control of TMD in adults.

Effect of adjunctive application of epigallocatechin-3-gallate and ethanol-wet bonding on adhesive-dentin bonds.

OBJECTIVES: To determine the effect of the combined use of epigallocatechin-3-gallate (EGCG) and ethanol-wet bonding (EWB) on resin-dentin bonds. METHODS: Sixty molars were sectioned, polished, and randomly divided into six groups (n=10) according to the following pretreatments: group 1, water-wet bonding (WWB); group 2, WWB with 0.02% (w/v) EGCG; group 3, WWB with 0.1% EGCG; group 4, EWB; group 5, EWB with 0.02% EGCG; and group 6, EWB with 0.1% EGCG. An etch-and-rinse adhesive was then used, followed by the resin composites building. The microtensile bond strength (MTBS), failure modes and interfacial nanoleakage were separately determined after 24h water storage or 10,000 runs of thermocycling. RESULTS: Both pretreatment method (P<0.05) and thermocycling (P<0.05) significantly influenced bond strength and nanoleakage. Irrespective of thermocycling, the 0.02% EGCG/ethanol (group 5) pretreated adhesive-dentin interfaces showed higher MTBS than the control group (P<0.05). Nanoleakage expression of all groups increased after thermocycling (P<0.05) except group 5. Adhesive failure was the main fracture pattern in all groups. CONCLUSION: This study showed that pretreatment with 0.02% EGCG/ethanol solutions can effectively improve immediate bond strength and bond stability of etch-and-rinse adhesives on dentin. CLINICAL SIGNIFICANCE: The adjunctive application of EGCG and EWB provides a new strategy for dentists to obtain the desired bond effectiveness during adhesive restoration in clinical practice.

Cyclooxygenase-2-1195G>A Polymorphism and Head and Neck Squamous Cell Carcinoma Susceptibility: A Meta-Analysis of 1564 Cases and 2346 Controls.

BACKGROUND The aim of this study was to investigate the association between cyclooxygenase-2 (COX-2) rs689466 (-1195 G>A) polymorphism and susceptibility to head and neck squamous cell carcinoma (HNSCC) by performing a meta-analysis. MATERIAL AND METHODS PubMed and Embase were searched for relevant cohort and case-control studies up to 13 March 2015. After data extraction and methodological quality assessment for eligible studies, the overall, subgroup, sensitivity, and cumulative meta-analyses were conducted using the Comprehensive Meta-Analysis software (version 2.2). RESULTS Finally, 5 case-control studies involving 1564 HNSCC patients and 2346 healthy controls were included. For overall population, the results of 3 genetic models showed significant association, while the other 2 presented negative association [A vs. G: OR=0.97-1.09, 95%CI=0.97-1.09; AA vs. GG: OR=1.26, 95%CI=1.01-1.57; AA vs. GA: OR=1.21, 95%CI=1.01-1.45); AA vs. (GG+GA): OR=1.20, 95%CI=1.01-1.43; (AA+GA) vs. GG: OR=0.98, 95%CI=0.84-1.15]. Publication bias was not assessed due to the limited number of included studies. CONCLUSIONS This meta-analysis indicated that COX-2 rs689466 polymorphism might be associated with increased susceptibility to HNSCC. We also suggest performing more relevant studies in order to enlarge the sample size and obtain more precise results.

Effects of different artificial ageing methods on the degradation of adhesive-dentine interfaces.

OBJECTIVES: To compare the effects of four commonly used artificial ageing methods (water storage, thermocycling, NaOCl storage and pH cycling) on the degradation of adhesive-dentine interfaces. METHODS: Fifty molars were sectioned parallel to the occlusal plane, polished and randomly divided into two adhesive groups: An etch-and-rinse adhesive Adper SingleBond 2 and a self-etch adhesive G-Bond. After the composite built up, the specimens from each adhesive group were sectioned into beams, which were then assigned to one of the following groups: Group 1 (control), 24h of water storage; Group 2, 6 months of water storage; Group 3, 10,000 runs of thermocycling; Group 4, 1h of 10% NaOCl storage; and Group 5, 15 runs of pH cycling. The microtensile bond strengths were then tested. The failure modes were classified with a stereomicroscope and representative interface was analyzed with a field-emission scanning electron microscopy (FESEM). Nanoleakage expression was evaluated through FESEM in the backscattered mode. RESULTS: The four artificial ageing methods decreased the bonding strength to nearly 50% and increased the nanoleakage expression of both adhesive systems compared with the control treatment. Adhesive failures were the predominant fracture modes in all groups. However, differences in detailed morphology were observed among the different groups. CONCLUSIONS: Water storage, thermocycling, NaOCl storage and pH cycling could obtain similar degradation effectiveness through appropriate parameter selection. Each in vitro artificial ageing method had its own mechanisms, characteristics and application scope for degrading the adhesive-dentin interfaces. CLINICAL SIGNIFICANCE: Water storage is simple, low-cost but time-consuming; thermocycling lacks of a standard agreement; NaOCl storage is time-saving but mainly degrades the organic phase; pH cycling can resemble cariogenic condition but needs further studies. Researchers focusing on bonding durability studies should be deliberate in selecting an appropriate ageing model based on the differences of test material, purpose and time.

[Study of pretreatment with ethanol to compensate premature volatilization of self-etch adhesive system].

OBJECTIVE: To evaluate the effect of pretreatment with ethanol on dentin to compensate premature volatilization of self-etch adhesive system. METHODS: Thirty-two intact human molars were randomly divided into two groups using a table of random numbers (n = 16): A, an acetone-base adhesive (G-bond) and B, an ethanol-based adhesive (Clearfile S(3) bond). Then each group was randomly assigned into foursub groups (n = 4) : group 1, no premature volatilization; group 2, premature volatilization; group 3, premature volatilization + stepwise ethanol pretreatments; and group 4, premature volatilization + absolute ethanol treatment. After composite resin building, microtensile bond strengths (MTBS) of each subgroup were then tested. Fracture modes were classified by stereomicroscopy and representative interface was observed by field-emission scanning electron microscopy (FE-SEM). RESULTS: For adhesive A, there was significant difference on MTBS among different subgroups (P < 0.05); the MTBS of group A2 [(26 ± 12) MPa] and A4 [(27 ± 7) MPa] was lower than that of group A1 [(41 ± 11) MPa] and A3 [(40 ± 11) MPa] (P < 0.05). No significant different was found between group A2 and A4 (P > 0.05); neither between group A1 and A3 (P > 0.05). For adhesive B, there was no difference on MTBS among different subgroups (P > 0.05).FE-SEM showed that the main fracture mode was located at the bottom of the hybrid layer for adhesive A groups, the collagen fibrils were capsulated by resin monomers more densely in group A1 and group A3 in comparison with other two subgroups.For adhesive B groups, the main failure modes were at the top of the hybrid layer. CONCLUSIONS: Premature volatilization can obviously decrease the bonding strength of acetone-base self-etch adhesives, but has no significant effect on ethanol-based self-etch adhesives. Dentin pretreatment with a series of increasing ethanol concentrations can effectively compensate the adverse effect of premature volatilization of acetone-base self-etch adhesives on bonding strength.

Effect of a functional desensitizing paste containing 8% arginine and calcium carbonate on the microtensile bond strength of etch-and-rinse adhesives to human dentin.

PURPOSES: To evaluate (1) the effect of a desensitizing paste containing 8% arginine and calcium carbonate on the microtensile bond strength between dentin and etch-and-rinse adhesive systems; and (2) to examine the dentin tubules occlusion quantitatively. METHODS: 48 freshly extracted intact human mandibular third molars were divided randomly into three groups. The mid-coronal dentin of each tooth was exposed and treated. Group A: no treatment; Group B: specimens were polished with a desensitizing paste containing 8% arginine and calcium carbonate using a rotary cup operating at a low speed for 3 seconds, followed by an additional duration of 3 seconds (total operation time of 6 seconds), according to the manufacturer's instructions; Group C: specimens were handled in the same way with the exception of an increased operation time of 9 seconds, twice (total operation time of 18 seconds). Each group was randomly divided into two subgroups in order to evaluate the effectiveness of two different adhesive agents. A two-step etch-and-rinse adhesive agent (Adper SingleBond 2) and a three-step etch-and-rinse adhesive agent (Adper ScotchBond Multi-purpose) were applied to dentin surfaces. Then, microtensile bond strengths of the six subgroups were tested. Dentin surfaces were analyzed using field-emission scanning electron microscopy (FESEM) and laser scanning confocal microscopy (LSCM). RESULTS: There was no significant difference in microtensile bond strength between the control group and the experimental groups treated with the 8% arginine and calcium carbonate desensitizing paste during the application of etch-and-rinse adhesives. Both FESEM and LSCM showed that the desensitizing paste occluded dentin tubules effectively.

Effect of pretreatment with calcium-containing desensitizer on the dentine bonding of mild self-etch adhesives.

Desensitizing agents are frequently applied to sensitive teeth and may affect subsequent resin bonding. The current study aimed to evaluate the bonding performance of two self-etch adhesives containing functional monomers to dentine pretreated with three new calcium-containing desensitizers. No desensitizer was applied in the control group. Groups 1, 2, and 3 were treated with an arginine-calcium carbonate-containing polishing paste, a casein phosphopeptide-amorphous calcium phosphate (CPP-ACP)-containing paste, and an experimental hydroxyapatite paste, respectively. G-Bond and Clearfil S(3) Bond were used for bonding after desensitizer treatments. The microtensile bond strength (µTBS) was tested (n = 20 beams per group) and failure mode distribution was analyzed. Scanning electron microscopy was used to observe the occlusion of dentinal tubules. The mean (±SD) µTBS values, expressed in MPa, of groups 1, 2, and 3 and the control group were, respectively, 30.81 (7.79), 44.41 (8.02), 31.49 (6.13), and 41.40 (8.67) for G-Bond and 39.63 (9.59), 32.55 (7.86), 37.50 (8.60), 27.90 (6.52) for S3 Bond. Most failures were recorded as adhesive failure (69.375%), instead of cohesive failure or mixed failure. The dentinal tubules were seldom plugged in group 2, but were mostly occluded in groups 1 and 3. Two-way anova indicated that desensitizer application in association with a compatible adhesive system should be used when endeavoring to control hypersensitivity without adverse interference in bonding.