Effect of water storage on microshear bond strength of four dental adhesive systems to dentin

AIM: To evaluate the microshear bond strength of 4 dental adhesive systems after 1 year-water storage. MATERIAL AND METHODS: The sample consisted of 120 cylinders of composite, obtained from 24 bovine incisors, which were divided into four experimental groups: G1-Scotchbond Multi-Purpose, G2-Single Bond 2, G3-Clearfil SE Bond, G4-Adper Easy One and two storage times in distilled water: T0 - 24h and T1 - 1 year. A bivariate analysis was performed using the ANOVA and Tukey test (α=0.05). Results were evaluated inter-and intra-group in both times. RESULTS: After 24 hours, G1T0 (39.68A ± 11.55) showed higher bond strength (MPa) followed by G2T0 (22.71B ± 4.07), G3T0 (18.94BC ± 7.29) and G4T0 (13.30C ± 3.94). After 1 year of storage only G1T1 (33.95A ± 6.35) and G3T1 (13.59BC ± 2.63) maintained the bond strength values (p ≥ 0.05), while G2T1 (10.62C ± 4.32) and G4T1 (4.49D ± 2.49) presented a decrease in this values. CONCLUSION: The hydrophobic two-step adhesive systems maintained the bond strength after 1-year water storage.

Low- level laser therapy for temporomandibular disorders ( tmd) treatment: a systematic review of randomized trials

AIM: Conducting a systematic review of randomized clinical trials focusing on the efficacy of LLLT on pain control in patients with TMD, diagnosed by the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). MATERIAL AND METHODS: Search was performed at PubMed/MEDLINE database with the terms: (1) "Laser AND temporomandibular disorders"; (2) "Laser AND temporomandibular disorders AND RDC/TMD"; (3) "Low-level laser therapy AND temporomandibular disorders"; (4) "Low-level laser therapy AND temporomandibular disorders AND RDC/TMD"; (5) "Low-level laser therapy AND temporomandibular joint dysfuntion syndrome"; (6) "Low-level laser therapy AND temporomandibular joint dysfuntion syndrome AND RDC/TMD"; (7) "Laser AND temporomandibular joint dysfuntion syndrome" (8) "Laser AND RDC/TMD"; (9) "Low-level laser therapy AND RDC/TMD". Inclusion criteria: articles need to be randomized clinical trial performed in humans; evaluate the effect of LLLT in the treatment of TMD diagnosed by the use of RDC/TMD; published in English or Portuguese in the last 10 years. Protocol studies and pilot studies were excluded. RESULTS: Ten studies were included. The type of laser used was Gallium Aluminum Arsenide (GaAlAs) diode, with exception of 1 paper, which used super pulsed Gallium Arsenide laser. Eight studies reported decreased in pain levels, in two articles there was no statistically significant difference between test and placebo groups. CONCLUSION: In most studies, LLLT was effective in pain remission, but there is no standardization in parameters like wavelength, output power and frequency. Studies with more complex experimental designs, standardized diagnostic criteria for TMD and defined protocols for the use of LLLT are needed to determine its efficacy in the treatment of TMD.

Análise comparativa entre os ensaios de cisalhamento e micro-cisalhamento / Comparative analysis between shear tests and micro-shear

O propósito deste estudo foi avaliar comparativamente a metodologia do teste da união dentina/compósito através do cisalhamento e micro-cisalhamento utilizando duas estratégias de união: autocondicionante e condicionamento ácido total. Quarenta incisivos bovinos tiveram suas coroas incluídas em tubos de PVC com resina acrílica. As faces vestibulares foram planificadas até a exposição do tecido dentário com lixas de carbeto de silício. Para o ensaio de cisalhamento, foi delimitada uma área de 4mm de diâmetro na qual foi aplicado o sistema adesivo de acordo com o fabricante. Um cilindro de compósito restaurador (Filtek Z250 - 3M ESPE) de 4mm de diâmetro e altura de de 5mm foi construído na área. As amostras para micro-cisalhamento foram confeccionadas utilizando-se tubos de Tygon com diâmetro interno de 0,7mm e altura de 0,5m nos quais o mesmo compósito restaurador foi inserido. O carregamento para ambos os testes foi realizado à uma velocidade de 1,0mm/min com fio ortodôntico de 0,3mm de diâmetro...

Síndrome de Classe II Divisão 1ª de Angle como conseqüência da respiração bucal / Class II Syndrome First Division of Angle as Consequence Breathing Buccal

O objetivo do presente estudo é estabelecer uma relaçäo entre a síndrome de classe II divisäo 1§ de Angle e as consequências que a respiraçäo bucal poderá provocar no desenvolvimento do complexo crânio facial e consequentemente nas posiçöes dentais