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Because the study of occlusion is a basic area in dentistry, its components, physiology and integration with the stomatognathic system (SS) have been the subject of interest in the scientific literature. However, the focus given to this issue has changed substantially. Currently, new approaches have been proposed in order to update concepts and to demonstrate the full integration and functionality of this system within the human body. With this approach, the authors proposed the following literature review aimed at gathering recent papers (published from 2000 to 2010) with innovative study design, methodology and/or results. The authors' intention is to show the main trends in the study of occlusion and the SS. The literature review was conducted in the PubMed database, using initially the term 'dental occlusion' as a key-word. As items of interest were found, papers were grouped by categories according to their main subject matter. Forty-seven articles were selected and the main categories obtained were: 1. functional magnetic resonance imaging (fMRI); 2. brain activation; 3. masticatory/occlusal function; 4. body function and physical performance; 5. osseoperception; 6. finite element models; and 7. occlusion and pain. Observing the current literature, the authors found that recent studies present different methodologies for the study of occlusion. These studies have allowed scientists to obtain detailed information about the physiology of occlusion and the SS, as well as about its integration in the body. Research in this area should be continued in order to clarify, in detail, the role of each component of the SS and its interaction with human physiology. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the effect of 37% carbamide peroxide on the bond strength of conventional or resin-modified glass-ionomer cements when used as a cervical barrier in endodontically-treated teeth., Materials and Methods: After root canal instrumentation and obturation, 40 specimens of the cement-enamel junction were obtained after transversal root canal sectioning from human extracted canines. The root canal specimens were standardized and filled with the following materials (n = 10, each group): G1: zinc phosphate (control), G2: Ketac glass-ionomer, G3: vitrebond glass-ionomer or G4: GC GL glass-ionomer. After 24 hours, the specimens were subjected to an application of 37% carbamide peroxide for 21 days, changed each 7 days and stored in an artificial pulp chamber. The specimens were then submitted to push-out bond strength testing with an electromechanical test machine (EMIC) and the failure mode in each specimen was analyzed with confocal microscopy (LEXT)., Results: G3 and G4 showed higher bond strengths values than the other groups (p < 0.05), and were similar to each other (p > 0.05). G1 showed the lowest bond strength value (p < 0.05)., Conclusion: Glass-ionomer cements showed higher bond strength values than the zinc phosphate cement, and resin-modified glass-ionomer cements presented the highest push-out values to root canal dentin (GC, GL and Vitrebond)., Clinical Significance: Glass ionomer cements are recommended to use as cervical barrier materials before the internal dental bleaching, but its efficiency is questionable.

Aim: This study evaluated the effect of ultrasonic vibration on the tensile strength required to remove intraradicular post cemented with different materials., Materials and Methods: Bovine teeth were selected, and 7 mm of the cervical root canals were prepared to size 5 Largo drill, the posts were cemented with zinc phosphate, Enforce (resin) or Rely X (glass ionomer). The specimens were divided into six groups (n = 10), according to the following procedures: GI-cementation with zinc phosphate associated with traction force; GII-cementation with zinc phosphate associated with ultrasonic activation and traction force; G111-cementation with Enforce associated with traction force; GIV-cementation with Enforce associated with ultrasonic activation and traction force; GV-cementation with Rely X associated with traction force; and GVI-cementation with Rely X associated with ultrasonic activation and traction force. The tensile test was conducted using the electromechanical testing machine, the force was determined by a specialized computer program and ultrasonic activation using the Jet Sonic Four Plus (Gnatus) device in 10P., Results: Concerning to average ranking, GI showed statistically significant difference in comparison with GII and GVI (p < 0.05); there was no statistical difference in GIII and GIV when compared to other groups (p > 0.05)., Conclusion: The ultrasound favored the intraradicular post traction regardless of the employed cement in greater or lesser extent., Clinical Significance: The post removal is a routine practice in the dental office, therefore, new solutions and better alternatives are need to the practitioner. We did not find in the literature many articles referring to this practice. Thus, the results from this study are relevant in the case planning and to promote more treatment options.

The aim of this study was evaluate the dental enamel after whitening treatment with Opalescence Boost PF™ 38%, correlating the structural alterations in the surface of the enamel with its respective pH and verify if whitened teeth submitted to different finishing and polishing techniques show similar surface texture to healthy teeth (control group). Sixty premolars were divided in 6 groups (n = 10), which had been immersed in artificial saliva during all the experiment. Protocol whitening was performed according to the manufacturer recommendations, and then the specimens were submitted to different polishing technique with Sof-Lex Pop On™ disks, Flex Diamond™ felt disks using two different micrometric polishing pastes (Enamelize™ and Diamond Polish™) and two nanometric polishing pastes (Lummina-E Diamond and Lummina-E Alumina), according to the groups. Representative specimens were analyzed in scanning electronic microscopy (SEM). Whitening gel used in this experiment had modified the morphologic aspect of the enamel surface. It was found that two nanometric polishing pastes (G5 and G6) promoted a less rough surface compared to control group even after the whitening process.

Background. Fracture by trauma is one of the most common types of dental injury in the permanent dentition among children and teenagers. Aim. The aim of this study was to report the treatment performed to an atypical dental trauma case in a maxillary central incisor of a young patient by means of reattachment of the tooth fragment. Case Description. A 12-year-old male patient suffered a vertical crown fracture to the maxillary right central incisor. After clinical and radiographic examinations, a conservative restorative treatment which consisted in the reattachment of the tooth fragment with flow resin was performed in order to preserve the dental element and to obtain maximum aesthetics. Conclusion. The reattachment of fractured fragment is a fast and easy technique that can be used successfully as an option to restore dental element which suffered trauma. Clinical Significance. This technique restores the aesthetics and function of the dental element with minimal discomfort to the patient.

This study evaluated three surface treatments and their effect on the shear bond strength between a resin cement and one of three ceramics. The ceramic surfaces were evaluated with scanning electron microscopy (SEM) as well. Specimens were treated with 50 μm aluminum oxide airborne particles, 10% hydrofluoric acid etching, or a combination of the two. Using a matrix with a center hole (5.0 mm x 3.0 mm), the ceramic bonding areas were filled with resin cement following treatment. The specimens were submitted to thermal cycling (1,000 cycles) and the shear bond strength was tested (0.5 mm/minute). The failure mode and the effect of surface treatment were analyzed under SEM. Data were submitted to ANOVA and a Tukey test (α = 0.05). Duceram Plus and IPS Empress 2 composite specimens produced similar shear bond strength results (p > 0.05), regardless of the treatment method used. Hydrofluoric acid decreased the shear bond strength of In-Ceram Alumina specimens. For all materials, surface treatments changed the morphological surface. All treatments influenced the shear bond strength and failure mode of the ceramic/resin cement composites.

This study evaluated factors that may influence the presence or absence of interproximal papillae. Clinical evaluation consisted of visual determination, and quantitative analyses were made using millimeter grids on radiographs. Patients (n = 45) were divided into three groups according to age. Data were analyzed using the chi-square test followed by the Student t test (α = .05). The distance from the contact point to the bone crest had significant influence on papilla presence in both anterior and posterior sites (P < .05), whereas the width between roots of adjacent teeth did not. The papilla was missing more frequently in anterior sites. The presence of papillae was not age-dependent.

This study compared the dimensions of gingival papillae in anterosuperior areas presenting at natural teeth (teeth sites) or single-tooth implants adjacent to natural teeth (implant-tooth sites) by analyzing determined distances. A total of 45 teeth and 46 implant-tooth sites were carefully selected. Clinical evaluation consisted of visual and quantitative analyses with millimeter grids on radiographs. Implant-tooth sites showed a smaller gingival papilla dimension than tooth sites (P < .01). Both evaluated distances (contact point to bone crest and between the roots of adjacent teeth or implant platform to root of adjacent tooth) in all groups significantly influenced the presence/absence of gingival papillae (P < .01).