Neurosensory analysis of tooth sensitivity during at-home dental bleaching: a randomized clinical trial.

Objective The objective of this study was to evaluate dental sensitivity using visual analogue scale, a Computerized Visual Analogue Scale (CoVAS) and a neurosensory analyzer (TSA II) during at-home bleaching with 10% carbamide peroxide, with and without potassium oxalate. Materials and Methods Power Bleaching 10% containing potassium oxalate was used on one maxillary hemi-arch of the 25 volunteers, and Opalescence 10% was used on the opposite hemi-arch. Bleaching agents were used daily for 3 weeks. Analysis was performed before treatment, 24 hours later, 7, 14, and 21 days after the start of the treatment, and 7 days after its conclusion. The spontaneous tooth sensitivity was evaluated using the visual analogue scale and the sensitivity caused by a continuous 0°C stimulus was analyzed using CoVAS. The cold sensation threshold was also analyzed using the TSA II. The temperatures obtained were statistically analyzed using ANOVA and Tukey's test (α=5%). Results The data obtained with the other methods were also analyzed. 24 hours, 7 and 14 days before the beginning of the treatment, over 20% of the teeth presented spontaneous sensitivity, the normal condition was restored after the end of the treatment. Regarding the cold sensation temperatures, both products sensitized the teeth (p<0.05) and no differences were detected between the products in each period (p>0.05). In addition, when they were compared using CoVAS, Power Bleaching caused the highest levels of sensitivity in all study periods, with the exception of the 14th day of treatment. Conclusion We concluded that the bleaching treatment sensitized the teeth and the product with potassium oxalate was not able to modulate tooth sensitivity.

Estudo clínico prospectivo e randomizado de restaurações de classe II utilizando resinas de baixa contração de polimerização / A prospective, randomized clinical study of class II restorations using low polymerization shrinkage composite resins

Objetivo: O objetivo deste estudo clínico, prospectivo, randomizado, duplo-cego, foi avaliar a sensibilidade pós-operatória, o desempenho clínico e os contatos interproximais após a utilização de três diferentes estratégias restauradoras. Materiais e métodos: 159 restaurações de Classe II foram realizadas em pré-molares e molares de 53 pacientes, com idade média de 48 anos (21- 78). Cada paciente recebeu ao acaso 3 restaurações, de acordo com os seguintes sistemas restauradores: PA- utilizou resina convencional, inserida pela técnica incremental (Peak Universal + Amelogen Plus, Ultradent); ABF- utilizou uma resina de baixa contração, inserida em incrementos únicos de até 4 mm, seguida da cobertura com resina nanoparticulada (Adper Single Bond+ Filtek Bulk Fill Flow+ Z350XT Body); XST- utilizou uma resina de baixa contração, inserida em incremento único de até 4 mm, seguida da cobertura com resina nanohíbrida, (XP Bond+ SDR+ TPH3). A sensibilidade pós-operatória foi avaliada utilizando uma escala analógica visual modificada (1- 6), em 24 h, 7, 30, 90 dias e 6 meses após as restaurações. Dois examinadores avaliaram o desempenho clínico das restaurações utilizando critérios USPHS modificados em Baseline, 6 meses e 1 ano após as restaurações. Os contatos interproximais foram avaliados com uma escala de classificação numérica (0-4) nos mesmos períodos que os critérios USPHS. Resultados: A maior média de sensibilidade foi relatada em 24h, sendo constatada redução significativa da sensibilidade espontânea após 30 dias, em todos os grupos. Quanto à sensibilidade ao frio, o grupo ABF não apresentou redução ao longo do tempo. Não houve diferença estatística quando a sensibilidade ao calor foi avaliada. Em relação ao desempenho clínico, cor, descoloração marginal e manchamento superficial mostraram diferenças entre os grupos. Somente o grupo XST não apresentou manchamento superficial após 1 ano. Não foram observadas diferenças entre os grupos em relação aos contatos interproximais. Conclusões: Os diferentes tipos de sistemas restauradores não influenciam na sensibilidade espontânea; no entanto, mediante ao estímulo frio, o sistema XST obteve a maior redução deste tipo de sensibilidade após 30 dias. Em relação ao desempenho clínico, início de descoloração marginal ocorreu para todos os grupos, sendo mais precocemente no sistema ABF. Um dos sistemas restauradores com resina de baixa tensão de polimerização (XST) apresentou redução do contato interproximal após 1 ano de avaliação(AU)

Objective: The aim of this prospective, randomized, double-blind clinical study was to evaluate postoperative sensitivity, clinical performance and interproximal contacts after using three different restorative strategies. Materials and methods: 159 Class II restorations were performed on premolars and molars of 53 patients, with a mean age of 48 years (21-78). Each patient randomly received 3 restorations, according to the following restorative systems: PAused conventional resin, inserted by the incremental technique (Peak Universal + Amelogen Plus, Ultradent); ABF- used a low- shrinkage resin, inserted in single increments of up to 4 mm, followed by coating with nanoparticulate resin (Adper Single Bond + Filtek Bulk Fill Flow + Z350XT Body); XST- used a low contraction resin, inserted in a single increment up to 4 mm, followed by coating with nanohybrid resin, (XP Bond + SDR + TPH3). Postoperative sensitivity was assessed using a modified visual analogue scale (1-6), at 24 h, 7, 30, 90 days and 6 months after the restorations. Two examiners evaluated the clinical performance of the restorations using modified USPHS criteria at Baseline, 6 months and 1 year after the restorations. The interproximal contacts were evaluated with a numerical classification scale (0-4) in the same periods as the USPHS criteria. Results: The highest mean sensitivity was reported in 24h, with a significant reduction in spontaneous sensitivity for all the groups after 30 days. Regarding the sensitivity to cold, the ABF group remained without reducing the sensitivity over time. There was no statistical difference when the heat sensitivity was evaluated. Regarding clinical performance, color, marginal discoloration and superficial spotting showed differences between the groups. Only the XST group did not show superficial spotting after 1 year. No differences were observed between groups in relation to interproximal contacts. Conclusions: Different types of restorative systems do not influence spontaneous sensitivity; however, when the cold stimulus was applied the XST system obtained the greatest reduction of this type of sensitivity after 30 days. Regarding clinical performance, beginning of marginal discoloration occurred for all groups, being earlier in the ABF system. One of the restorative systems with low-shrinkage stress polymerization resin (XST) showed reduction of interproximal contact after 1 year of evaluation(AU)