Influence of myofunctional therapy on the perioral muscles. Clinical and electromyographic evaluations

The purpose of this study was to evaluate the influence of oral myofunctional therapy on the superior and inferior orbicularis oris (OOS and OOI) and mentalis (MT) muscles at rest and with lips closed in mouth breathing patients with no nasal airway obstruction. The sample consisted of 13 children aged 5-10 years. Clinical and electromyographic evaluations were performed before and after treatment. The results showed that muscles (P < 0.05) and functions (P < 0.01) improved after therapy, which can be observed by clinical evaluations. The electrical activity increase between rest and closed lip positions was statistically significant for the muscles studied. Before therapy the significant minimal level (s.m.l.) was P<0.01 and after therapy it was P<0.05. When the difference between the rest and closed lip positions before and after therapy was compared, a statistically significant decrease (P <0.05) in the electrical activity of the OOI and MT muscles was observed. There was no correlation between the root-mean-square (RMS) of the OOI and MT muscles with the morphological and functional evaluations. The therapy can improve morphology and function of the muscles in mouth breathing patients with no nasal airway obstruction.26756456

Effects of resin luting agents and 1% NaOCl on the marginal fit of indirect composite restorations in primary teeth

Objective: The purpose of this study was to provide information regarding the marginal adaptation of composite resin onlays in primary teeth previously treated with 1% sodium hypochlorite (NaOCl) (pulp irrigant) using two different resin luting agents. Material and Methods: Forty extracted sound primary molars had their crowns prepared in a standardized machine and were randomly divided into 4 groups (n=10): G1 (1% NaOCl irrigation+EnForce); G2 (EnForce); G3 (1% NaOCl irrigation+Rely X); G4 (Rely X). The onlays were made with Z250 composite resin on plaster models. After luting, the tooth/restoration set was stored in 100% relative humidity at 37 degrees C for 24 h and finished with Soflex discs. Caries Detector solution was applied at the tooth/restoration interface for 5 s. The specimens were washed and four digital photos of each tooth were then taken. The extents of the gaps were measured with Image Tool 3.0 software. The percentage data were submitted to a Kruskal-Wallis test (alpha=0.05). The Relative Risk test analyzed the chance of a gap presence correlated to each group. Results: There were no statistically significant differences (p>0.05) among the groups. The relative risk test revealed that some groups were more apt to have a presence of gaps than others. Conclusion: Neither the 1% NaOCl treatment nor the resin luting agents caused any alterations in the dental substrate that could have influenced the marginal adaptation of composite onlays in primary teeth.19545546

Marginal adaptation of pit and fissure sealants after thermal and chemical stress. A SEM study

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Purpose: To evaluate the in vitro marginal adaptation (gap formation) in the fissure of different sealer materials (resin sealant, glass-ionomer cement, resin-modified glass-ionomer cement, and adhesive system) submitted to thermal and chemical stress, using scanning electron microscopy evaluation (SEM). Methods: 80 impacted human third molars were randomly assigned to the following experimental groups (n=10): FluroShield (F), Helioseal Clear Chroma (H), Vitremer (V), Fuji II-LC (FII), Ketac-Molar (KM), Fuji IX (FIX), Single Bond (SB), and Clearfil Protect Bond (CF). All groups were subjected to thermocycling and 14 days of pH cycling. A blinded and calibrated examiner performed SEM analysis. Gap formation was scored according to: 0= no sealant marginal gaps; 1= sealant marginal gaps present or total sealant loss. The score 0 was considered a success, while score 1 represented failure. Data were analyzed by Kruskal-Wallis and Bonferroni tests (P< 0.05). Results: The success rates of SB (100%) and V (90%) were similar, but statistically superior to F (30%), H (20%), FIX (20%0), and CF (0%) (P< 0.05). A tendency for similar behaviors of FII and KM to SB and V was observed and for similar behaviors of F, FIX and H to CF. The worst results were obtained for CF. (Am J Dent 2008;21:377-382).216377382Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

NaOCl effects on primary and permanent pulp chamber dentin

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Objectives: The dentin quality of primary and permanent pulp chamber was inspected by Fourier-transformed Raman spectroscopy (FT-Raman) and scanning electron microscopy (SEM). Fragments of pulp chamber dentin were obtained from 20 human molar crowns (primary and permanent). Methods: The fragments were assigned to 8 groups (n = 5)-Primary teeth: G1, pulp chamber dentin; G2, pulp chamber dentin irrigated with NaOCl 1% (30 min); G3, pulp chamber dentin irrigated with NaOCl 1% (30 min) and etched by 35% phosphoric acid; G4, pulp chamber dentin etched by 35% phosphoric acid. Permanent teeth: G5, pulp chamber dentin; G6, pulp chamber dentin irrigated with NaOCl 1% (30 min); G7, pulp chamber dentin irrigated with NaOCl 1% (30 min) and etched by 35% phosphoric acid; G8, pulp chamber dentin etched by 35% phosphoric acid. The spectra were subjected to the Cluster analysis. The SEM images were scored. Results: Inorganic content: There was a difference between primary and permanent dentin. The groups treated with NaOCl were statistically similar between them, but differed from the groups not treated. Organic content: There was no difference between primary and permanent dentin. The groups became similar after NaOCl and phosphoric acid treatments. The microscopic images showed the presence of calcospherites on permanent dentin and their absence on primary dentin. Conclusions: The NaOCl changed the inorganic content in both dentitions; regardless of the following phosphoric acid etching. However, the chemical changes caused by NaOCl were not detected by SEM when it was followed by etching. (C) 2008 Elsevier Ltd. All rights reserved.369745753Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)FAPESP [#05/50811-9, 01/133848

Compressive strength recovery by composite onlays in primary teeth. Substrate treatment and luting agent effects

Objectives: To evaluate 1% NaOCl treatment and two resin luting agent effects on compressive strength recovery in composite onlays on primary teeth and to analyze the fractures type. Methods: Forty sound primary molars crowns were prepared in the standard machine and randomly divided into four groups (n = 10): G1 (1% NaOCl/30 min + EnForce); G2 (without 1% NaOCl EnForce); G3 (1% NaOCl/30 min + Rely X); G4 (without 1% NaOCl + Rely X). The onlays were made using Z250 composite on plaster models. Ten sound teeth were used as control group (CG). All groups were submitted to compression mechanic test in a universal test machine INSTRON at 1 mm/min cross-head speed. After that, the data (kgf) were submitted to ANOVA test (alpha = 0.05). Finally, the fracture types were classified in a crescent scale (1-5) related with severity degree and submitted to Fisher's Exact Test (p 0.05). The results from fracture type showed that types 5 and 4 fractures (most severe) present the highest percentage to experimental groups. Conversely, the CG showed higher percentage of fracture types 2 and 3. Conclusions: This research found that the composite onlays recovered the compressive strength compared to sound teeth, regardless of the substrate treatment and cement agent used. Nevertheless, no group showed similar type of fractures to CG, which had more frequency of less severe fracture types. (c) 2005 Elsevier Ltd. All rights reserved.34747848

Influence of NaOCI Irrigation and Water Storage on the Degradation and Microstructure of the Resin/Primary Dentin Interface

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Purpose: To evaluate the influence of NaOCI irrigation and water storage on the degradation and microstructure of the resin/dentin interface of primary teeth bonded with three different adhesive systems using the microtensile bond strength test (mu TBS) and scanning electron microscopy (SEM). Materials and Methods: Ninety sound primary molars were used. Eighteen groups were formed according to different adhesive systems (Adper Single Bond 2, SB; Clearfil Protect Bond, CP; Adper Prompt L-Pop, APL) with or without 0.5% NaOCI irrigation and water-storage time (24 h, 45 days, 90 days). The middle dentin was exposed. In the NaOCI group, NaOCI irrigation was performed for 30 min, and all groups were restored with composite (Charisma). Sticks with a 1-mm(2) cross-sectional area were prepared for the pTBS test. The data were analyzed by ANOVA and Tukey's test (p < 0.05). The failure modes, presence or absence of resin tags, and the resin/dentin interface were evaluated by SEM, and data were analyzed using Cochran-Mantel-Haenszel statistics (p < 0.05). Results: The pTBS of APL was significantly lower than the other groups regardless of treatment and storage time. A significant decrease of pTBS values after 90 days of water storage occurred only in the non-NaOCI irrigation groups. After 90 days of storage, resin tags partially disappeared in APL and CP, and in SB, 100% of the resin tags remained. Conclusion: The choice of adhesive system is one of the factors when bonding to primary dentin is considered. In this study, the etch-and-rinse and the two-bottle self-etching adhesive system produced the highest pTBS values irrespective of prior NaOCI irrigation even up to 90 days of water storage.133213220Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)FAPESP [05/58808-7