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.

The adjunctive effect of photodynamic therapy for residual pockets in single-rooted teeth: a randomized controlled clinical trial.

Residual pockets are challenging sites that require additional periodontal therapy. The aim of this study was to evaluate the effect of a single photodynamic therapy (PDT) as an adjunct to scaling and root planning (SRP) in residual pockets in single-rooted teeth. A blind, split-mouth, randomized controlled clinical trial was conducted in systemically healthy subjects presenting at least two residual pockets (probing pocket depth (PPD) ≥ 5 mm with bleeding on probing (BoP)) in single root teeth in supportive periodontal therapy. The selected sites were assigned to receive (1) PDT + SRP or (2) SRP. In sites treated by PDT as adjunctive to SRP, the laser system included a handheld battery-operated diode laser with a wavelength of 660 nm, a power output of 60 mW, and energy density of 129 J/cm(2), together with methylene blue as a photosensitizer (10 mg/ml). Clinical parameters were assessed at baseline and 3 months post-therapies. Clinical parameters improved significantly after both therapies (p < 0.05), whereas higher probing pocket depth reduction and clinical attachment level gain were observed in the PDT + SRP group at 3 months (p < 0.05). In addition, sites treated by the combined approach yielded a significant reduction in the number of sites with PPD <5 mm without BoP after 3 months compared to sites treated by conventional SRP alone (p < 0.05). PDT as an adjunctive to mechanical debridement demonstrated additional clinical benefits for residual pockets in single-rooted teeth and may be an alternative therapeutic strategy in supportive periodontal maintenance.

Diagnóstico de cárie oclusal in vitro com laser fluorescente em dentes humanos submetidos à desmineralização e remineralização / Diagnostic of occlusal caries in vitro by fluorescent laser on demineralization and remineralization of human teeth

O objetivo do presente estudo foi avaliar in vitro, o diagnóstico de cárie oclusal em dentes humanos submetidos ao processo de desmineralização e remineralização, utilizando laser fuorescente. Foram utilizados trinta terceiros molares humanos hígidos, os quais foram divididos em três diferentes grupos de tratamento: Grupo Controle - dentes imersos em solução remineralizante; Grupo Des - dentes imersos em solução desmineralizante e Grupo Des-Re- dentes imersos em solução desmineralizante e em solução remineralizante. Os dentes de cada grupo foram inicialmente submetidos à avaliação para diagnóstico de cárie oclusal utilizando um laser fuorescente e ao final de cada tratamento as amostras foram avaliadas novamente por três examinadores calibrados entre si (correlação de Spearman r=0,87). Os resultados mostraram que o laser fuorescente foi capaz de detectar as variações minerais ocorridas na estrutura dental quando os mesmos foram submetidos ao processo de desmineralização (p<0,05), no entanto o laser fuorescente não foi capaz de detectar diferença signifcativa (p>0,05) em dentes remineralizados. O laser fuorescente pode ser utilizado como um meio auxiliar no diagnóstico de cárie oclusal, porém pode apresentar resultados falso-positivos em relação ao ganho mineral.

The aim of this study was to evaluate in vitro diagnosis of occlusal caries in teeth submited to the demineralization and remineralization, using laser fuorescence. Thirty human third molars were used, which were divided into three diferent treatment groups: Group Control - teeth immersed in remineralizing solution, Group Des - tooth immersed in demineralizing solution and Group De-Re - teeth immersed in demineralizing solution and in remineralizing solution. The teeth of each group were initially subject to an assessment for the diagnosis of occlusal caries using a laser fuorescent and the end of each treatment the samples were evaluated again by three calibrated examiners from each other (Spearman correlation r = 0.87). The results showed that the fuorescent laser was able to detect minerals changes in tooth structure when they were submited to the demineralization (p<0.05), however the laser fuorescence was not able to detect a signifcant diference (p>0.05) in teeth remineralized. The fuorescent laser can be used as a complementary tool in the diagnosis of occlusal caries, but may have false-positive results in relation to mineral gain on dental structural.