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Objectives: This study aimed to establish a single-session associative protocol for non-restorative management of dentin hypersensitivity (DH). Materials and Methods: Twenty-four individuals with DH and a minimum sensitivity level of 4 on the visual analog scale (VAS) were selected. The study was conducted in a split-mouth design, with each participant (n = 20) having at least 1 affected tooth in all quadrants. The management protocols consisted of control group: universal adhesive, Neural Desensitizing Protocol group: 5% potassium nitrate, Mixed Desensitizing Protocol (PAM) group: 5% sodium fluoride and 5% potassium nitrate, Remineralizing Desensitizing Protocol (PDR) group: surface-partially reacted glass technology photopolymerizable varnish. Evaluations were performed immediately after application, at 1 week, 1 month, 2 months, and 12 months using the VAS sensitivity test. Results: The scores were subjected to statistical analysis using the Friedman test (p < 0.05), Durbin-Conover test (p < 0.05), and Wilcoxon test (p < 0.05). At the 12-month evaluation, all groups showed statistically significant differences compared to the initial assessment. For the evaluation after 12 months, there was a statistically significant difference between the PAM group, the control group, and the PDR group. Conclusions: It can be concluded that all groups were effective in controlling DH, but there were significant results in the control group and PDR group. The clinical relevance of this study is to demonstrate that the application of single-session desensitizing protocols can be effective in controlling DH for up to 12 months. Trial Registration: Brazilian Clinical Trials Registry Identifier: RBR-4r63d7s.

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OBJECTIVES: This study evaluated the linear dimensional change of polymerization of three materials and two techniques of the union of molding transfers for implant-supported prostheses used in the open-tray technique. MATERIALS AND METHODS: A nylon maxilla-shaped matrix was made, two osseous integrated implants were installed, and, over these two, straight conical mini-pillars were installed. Open-tray impression transfers were attached to the mini-pillars, and a silicone guide was made to standardize the connections between the transfers. The samples were divided into six groups (n = 20): PA (Pattern Resin LS, chemically activated acrylic resin in the single step technique); DU (Durallay, chemically activated acrylic resin in the single step technique); BI (Protemp4, bisacrylic resin in the single step technique); PAC (Pattern Resin LS in sectioning and joining of segments technique); DUC (Durallay, in sectioning and joining of segments technique); and BIC (Protemp4, in sectioning and joining of segments technique). The linear dimensional change values that occurred among these transfers were measured in a profile projector (VB300; Starret) coupled to the Quadra Check device, with a resolution of 0.001 mm, performed by a single calibrated operator. STATISTICAL ANALYSIS: Data were submitted to a two-way analysis of variance and Tukey's test (p < 0.01). RESULTS: Statistically significant mean values were found in all comparisons. The PA showed the lowest mean values (µm) of linear dimensional change, both in the single-step technique and in the sectioning and joining technique, in the following order: BI 255.73 (3.81), DU 173.75 (2.30), PA 95.97 (3.20), BIC 23.82 (1.71), DUC 20.85 (2.53), and PAC 13.27 (2.09). The single-step technique showed the worst results, regardless of the material. CONCLUSION: The sectioning and joining technique reduced the dimensional change in all materials, and the Pattern Resin LS showed the lowest shrinkage mean values, followed by Durallay and Protemp4.

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OBJECTIVE: To evaluate and compare the friction of different ligature modes used in orthodontics, and to propose a new ligature model for conventional brackets ("H low-friction orthodontic ligature). MATERIALS AND METHODS: Samples were randomly divided into seven experimental groups: (1) resin H ligature (H3D), designed by the authors of this study and produced in a 3D printer, with conventional bracket; (2) metal H ligature (HFM), with conventional bracket; (3) passive self-ligating bracket (SLP); (4) "8" low-friction unconventional elastic (LT8), with conventional bracket; (5) loose conventional metal ligature (MLS), with conventional bracket; (6) conventional metal ligature fully tightened (MLT), with conventional bracket; (7) conventional elastic ligature (CEL), with conventional bracket-control. All samples were subjected to mechanical static friction testing using the EMIC DL 2000 universal testing machine. STATISTICAL ANALYSIS: To assess the normality requirement, the Shapiro-Wilk test was used, which showed a non-normal distribution for the means of the groups (p < 0.05). Therefore, statistical tests were performed to assess the existence of statistically significant differences between the groups through the Kruskal-Wallis, followed by Dunn's test, pairwise comparison, p < 0.05. RESULTS: The results obtained showed lower friction values for HFM (0.002 kgf), SLP (0.003 kgf), and LT8 (0.004 kgf)-these did not differ statistically from each other. These were followed by H3D (0.020 kgf), MLS (0.049 kgf), CEL (0.12 kgf), and, finally, MLT (0.21 kgf). CONCLUSION: The lowest friction value was found for the metal H ligature, similar to the self-ligating bracket and the "8" low-friction unconventional elastic. The resin H ligature presented intermediate friction values and the highest friction force was found for the MLT group.

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Introduction: Dentin adhesives provide union between the dental substrate and composite resin, but this union can be influenced by the cleaning agent. Objective: Evaluate the use of ozonated water as a cavity cleaning solution. Material and method: 40 bovine dental crowns were selected, divided into four groups: AD (dentin cleaning with distilled water) and AO (dentin cleaning with ozonized distilled water). Each group was divided into two storage periods (24h and 30 days) kept at 37 °C. The selected universal system adhesive was employed according to the manufacturer's instructions and light cured for 20 seconds. At that time, three cylinders were made (Tygon matrix with an internal diameter of 2 mm and a height of 2 mm) of composite resin in the crowns in the cervical, médium, and incisal regions and light cured for 30 seconds. After storage, the bonding strength was tested by micro-shear, and fracture type analysis was performed. The data were submitted to statistical analysis using the Shapiro-Wilk test with a significance level of 95%, ANOVA, and Turkey. Result: There was a statistically significant difference between the bond strength values, only in the intergroup analysis for the time of 24 hours, between the middle third of the groups (LDAO24 = 2.70 (± 2.39); LDAO30 = 3.82 (± 2.31)). The predominant fracture type for both groups was an adhesive fracture, except in the medium and incisal thirds of the AD, which was a cohesive dentin fracture. Conclusion: The utilization of ozone did not change the bond strength adhesive.

Introdução: Os adesivos dentinários proporcionam união entre o substrato dental e resina composta, porém esta união pode ser influenciada pelo agente de limpeza. Objetivo: Avaliar a influência na resistência de união (RU) de um sistema adesivo universal associado à da água ozonizada como solução de limpeza cavitária. Material e método: Foram selecionadas 40 coroas de dentes anteriores bovinos divididos em 4 grupos: AD (limpeza dentinária com água destilada) e AO (limpeza dentinária com água destilada ozonizada). Cada grupo foi subdividido em outros dois grupos de acordo com o tempo de armazenamento (24h e 30 dias) armazenados a 37ºC. A limpeza dentinária foi realizada por meio de uma seringa de 60mL de cada solução e fricção por 10 segundos. O sistema adesivo universal selecionado foi aplicado de acordo com as instruções do fabricante e fotoativado por 20 segundos. Em seguida, foram confeccionados 3 cilindros (matriz Tygon com um diâmetro interno de 2 mm e 2 mm de altura) de resina composta nas coroas nas regiões cervical, média e incisal e fotoativados por 30 segundos. Após o armazenamento foi realizado o teste de RU por microcisalhamento e análise do tipo de fratura. Os dados coletados foram submetidos a análise estatística através do teste de Shapiro Wilk com nível de significância de 95%, ANOVA e Tukey. Resultado: Houve diferença estatística significativa entre os valores de RU apenas na análise intergrupos para o tempo de 24 horas, entre o terço médio dos grupos (LDAO24 = 2,70 (± 2,39); LDAO30 = 3,82 (± 2,31)). O tipo de fratura predominante para ambos os grupos em todos os tempos foi de fratura adesiva, com exceção ao terço médio e incisal do AD, que foi fratura coesiva de dentina. Conclusão: A utilização do ozônio não alterou a resistência de união adesiva.

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This study evaluated the effect of auricular acupuncture (AA) on physical (PA) and emotional (EA) aspects of patients with temporomandibular disorders (TMDs) and compared the effect of AA with those of Sham and occlusal splints (OS). In accordance with the CONSORT guidelines, patients with TMDs were evaluated by axes I and II of the RDC-TMD. The patients were allocated among three groups: OS, Sham and AA; and followed for 8 weeks. Both intragroup and intergroup evaluation for quantitative variables were analyzed with ANOVA, one-way, followed by the Tukey test. Qualitative variables were analyzed with the Kruskal-Wallis, and Dunn tests (intergroup evaluation) and for intragroup analyses, the Friedman and Wilcoxon tests were applied. At the end of the experiment, the chi-squared test was applied to compare the three groups with respect to the number of variables that had shown improved scores. The adopted level of significance for all tests was α = 5%. Intragroup analysis showed that, in the Sham group, no improvement in performance was seen in either EA and significant was improvements in 5 variables for 9 for PA, while in the AA group, significant improvements were observed in 2 variables for EA and in 9 for PA. In the OS group at the end of this study, significant improvements were observed in 8 and 8 variables for EA and PA, respectively. The analysis of therapies used revealed that the number of variables exhibiting significantly improved outcomes after treatment was similar between the AA and OS groups, whereas the sham group showed statistically significant differences when compared with the other two groups. In conclusion, this study demonstrated that AA applied at a specific TMJ ear point was able to bring about improvements in patients with TMDs, with outcomes similar to those in patients treated with an OS. CLINICAL TRIAL REGISTRATION: RBR-69ynnw (Brazilian Registry of Clinical Trials).

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AIM AND OBJECTIVE: This study aimed to evaluate the effect of ozonated water used as an irrigant and dentin-cleaning solution on the bond strength of fiberglass pins in vitro, comparing it with the commonly used solutions. MATERIAL AND METHODS: Seventy-seven bovine roots were randomly divided into seven groups according to the irrigant and dentin-cleaning solution to be used: HP/HP, 2.5% sodium hypochlorite; DA/DA, distilled water; CHX/CHX, 2% chlorhexidine; OA/OA, 4 ppm ozonated water; HP/DA; HP/CHX; and HP/OA. In each group, the root canals were endodontically prepared by using the corresponding irrigant and stored in DA; after 7 days, they were cleared and cleaned with the corresponding cleaning solution. The fiberglass pins were cemented by using self-adhesive cement. After 7 days, the roots were sectioned (six discs each) and submitted to the push-out test. The type of fracture was analyzed with a 4.5x stereoscopic magnifying glass. The data were analyzed by the analysis of variance and the Tukey test at a 5% significance level. RESULTS: The OA/OA (11.67), HP/HP (11.21), and HP/OA (9.71) groups showed the highest mean push-out bond strength (MPa) in the cervical third. The same trend was maintained in the middle and apical thirds. CONCLUSION: Ozonated water and 2.5% sodium hypochlorite are the most relevant solutions for root dentin treatment. CLINICAL RELEVANCE: Teeth treated with ozonated water, sodium hypochlorite, and a combination of the two showed greater bond strength than those treated with other solutions.

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PURPOSE: To evaluate the effect of two desensitizing agents applied before in-office bleaching, on the degree of whitening and dentin sensitivity. METHODS: Participants were randomly assigned to the groups, according to the desensitizing agent used, with n=10 for each one. The bleaching was performed with 35% hydrogen peroxide, divided according to the desensitizing agent used prior to the bleaching procedure: Placebo (PL); Desensibilize KF with potassium nitrate and 0.2% sodium fluoride (PN); and Oxa-Gel with potassium oxalate (PO). The level of color saturation was assessed at the beginning of treatment and after 1 week of its completion by means of comparative method with the aid of a color scale. The degree of sensitivity (DS) was noted by the subjects with the aid of a visual scale throughout the time that the bleaching agent remained in contact with the teeth (5, 10, 15, 20, 25 and 30 minutes) as well as 1, 24 and 48 hours after the end of application. Pain and the degree of color saturation were evaluated using the Shapiro-Wilk test. The DS was assessed by Kruskal-Wallis and Dunn's tests. The color was evaluated by ANOVA and Tukey's HSD. RESULTS: There was no significant difference in the degree of bleaching among the groups. DS was significantly more accentuated in the 48-hour period. The DS was significantly higher for the PL group and significantly lower for the PO group. The desensitizing agents reduced the DS without affecting the effectiveness of the bleaching treatment. CLINICAL SIGNIFICANCE: Both desensitizing agents provided greater control over pain compared to the placebo group. Potassium oxalate showed greater pain control than potassium nitrate. Both desensitizing agents tested did not interfere in the degree of whitening.

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OBJECTIVES: Conduct a histological comparison of the pulp response to different materials, with a focus on the continuity and morphology of the mineralized barrier after direct pulp capping. MATERIALS AND METHODS: One hundred and eight maxillary first molars of 54 Wistar rats were subject to direct pulp capping and divided into three groups according to the materials used: calcium hydroxide (CH), mineral trioxide aggregate (MTA), and Biodentine. All cavities were sealed, and the animals were euthanized at 7, 14, and 21 days. Descriptive histological evaluation of the inflammation and formation of the mineralized barrier was performed. STATISTICAL ANALYSIS: Statistical analyses were performed using the Kruskal-Wallis test, which was complemented by the Dunn test; differences with p < 0.05 were considered statistically significant. RESULTS: The results showed that MTA and Biodentine elicited less intense inflammatory reactions than CH. With respect to the formation and quality of the dentin barrier formed, differences were observed at 21 days between the analyzed groups; the best results being obtained following treatment with MTA and Biodentine. CONCLUSION: MTA and Biodentine induced formation of a more continuous and uniform mineralized barrier with less intense pulp response than CH.

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OBJECTIVES: The aim of this study was to evaluate the bonding strength of self-adhesive luting cement to zirconia under different surface treatments. MATERIALS AND METHODS: Thirty-two zirconia samples were randomly divided into eight experimental groups based on the surface treatment employed (Control: no surface treatment; PMM: wear with diamond bur; JAT: blasting with glass beads; PMA: wear with a medium-roughness milling machine; Primer: primer application on the surface without treatment; PMM +Primer: PMM treatment plus primer application; JAT+Primer: JAT treatment plus primer application; and PMA+Primer: PMA treatment plus primer application). Cement cylinders were built on the ceramic surfaces, and the groups were subdivided according to the storage time employed (i.e., 24 hours or 60 days). After storage, the samples were subjected to microshear testing. STATISTICAL ANALYSIS: The Kruskal-Wallis test followed by the Dunn test was employed for comparison between the groups (p < 0.05). RESULTS: The PMM group yielded the optimal results and the mean values increased after both storage times following the primer application. The Control, PMA, and JAT groups gave similar results after 24 hours, while the JAT group gave superior results following primer application over this storage time. After 60 days of storage, all groups gave improved results following chemical treatment with a primer. CONCLUSION: It was concluded that mechanical preparation using the diamond bur followed by primer application significantly improved the bond strength between the ceramic and the luting cement.

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OBJECTIVE: This study evaluates the bond strength of two compositions of aesthetic translucent zirconia (TZ). MATERIALS AND METHODS: For this evaluation, test specimens were prepared from ICE Zirkon TZ and Prettau Anterior zirconia (PAZ) that were stored in distilled water at 37°C for two time periods: T1 (24 h) and T2 (90 days) to simulate aging. Two factors were evaluated for the samples-ceramic and aging time. The samples were subjected to tests of microshear strength and fracture type and were evaluated using scanning electron microscopy. RESULTS: The results were analyzed using the D'Agostino test, analysis of variance, and Tukey's test (p < 0.01). Statistically significant differences were observed for ceramic type and aging time. CONCLUSION: The results showed that PAZ provides significantly superior performance to TZ at the two aging times evaluated.