summary  The purpose of this study is to evaluate the interocclusal appliance efficiency in patients with temporomandibular disorder (TMD), by using computerized electromyographic (EMG) evaluation in the rest position of the mandible. Twenty‐two patients (male and female) with TMD symptoms, between 18 and 53 years of age, were examined. EMG evaluations were performed before the treatment and during the 90th, 120th and 150th day of using the interocclusal appliance therapy. In the 90th and 120th day, inserting canine guidance and group function disclusion, respectively, changed interocclusal appliance. The results showed that group function disclusion caused shorter EMG activity in the mandible rest position for the anterior temporalis muscle.

This study investigated, through computerized electrognathographic evaluations (K6-I Diagnostic System, Myotronics-Noromed Inc., Tukwila, USA), the mandibular movement pattern of 16 patients rehabilitated with complete dentures presenting no symptoms of stomatognathic functional alterations. The patients were instructed to wear an intra-oral appliance for occlusal plane coverage over their usual superior denture and were then rehabilitated with new dentures preserving a free-way space of 3 mm. After sixty days, the occlusal vertical dimension was increased and the modified inferior dentures were used for another 60 days. The obtained results were submitted to the Tukey Test and to the Friedman test, depending on which variable was under consideration, both at a significance level of 5%. The data revealed a significant decrease in free-way space when the first and the last evaluations were compared. No significant differences were found during opening and closing. It was concluded that the presence of a free-way space at the end of the treatment confirms the importance of its existence for maintaining the balance of the masticatory system, assuming the occurrence of a postural repositioning.

The aim of this study was to evaluate the fracture resistance of allceramic zirconia crowns, submitted to thermal and mechanical fatigue. Sixty bovine incisors were prepared to receive complete-coverage all-ceramic crowns. The crowns were fully made with zirconia Y-TZP using the CAD/CAM (Computer-Aided Design / Computer-Aided Manufacturing) Zirkonzahn® system. The specimens were assigned to four groups (n=15) according to each luting agent used: G1 -zinc phosphate; G2 -resin cement; G3 -glass ionomer cement; and G4 -resin-modified glass ionomer cement. The crowns were cemented using a pneumatic press with a static load of 9 kgf and submitted to an aging thermal/mechanical fatigue test, considering 60,000 cycles for the mechanical (load: 84 N -frequency: 4 Hz) and 125 cycles (4 -55 °C) for the thermal mode. The fracture resistance test was carried out using a load machine (Instron) at a speed of 1 mm/min. Data were submitted to ANOVA and Tukey test. Fracture resistance of the crowns luted with resin modified glass ionomer was observed to be significantly lower (1182,68 N ± 112,24) than that of the crowns luted with zinc phosphate cement (1448,51 N ± 182,32) and glass ionomer (1389,86 N ± 126,88) (p <0.05). No statistically significant difference was found between G1 and G3 (p> 0.05). The crowns in G2 showed no significant difference (1358,15 N ± 272,95) from those in the other groups. The fracture resistance of zirconia crowns was influenced by the luting agents.

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