The restoration of endodontically treated teeth is a topic that is extensively studied and yet remains controversial. This article emphasizes the characteristics of endodontically treated teeth and some principles to be observed when restorations of these teeth are planned. It was concluded that the amount of remaining coronal tooth structure and functional requirements determine the best way to restore these teeth, indicating the material to be used, direct or indirect restorations, associated or not to posts.
Several impression materials are available in the Brazilian marketplace to be used in oral rehabilitation. The aim of this study was to compare the accuracy of different impression materials used for fixed partial dentures following the manufacturers' instructions. A master model representing a partially edentulous mandibular right hemi-arch segment whose teeth were prepared to receive full crowns was used. Custom trays were prepared with auto-polymerizing acrylic resin and impressions were performed with a dental surveyor, standardizing the path of insertion and removal of the tray. Alginate and elastomeric materials were used and stone casts were obtained after the impressions. For the silicones, impression techniques were also compared. To determine the impression materials' accuracy, digital photographs of the master model and of the stone casts were taken and the discrepancies between them were measured. The data were subjected to analysis of variance and Duncan's complementary test. Polyether and addition silicone following the single-phase technique were statistically different from alginate, condensation silicone and addition silicone following the double-mix technique (p ≤ .05), presenting smaller discrepancies. However, condensation silicone was similar (p ≥ .05) to alginate and addition silicone following the double-mix technique, but different from polysulfide. The results led to the conclusion that different impression materials and techniques influenced the stone casts' accuracy in a way that polyether, polysulfide and addition silicone following the single-phase technique were more accurate than the other materials.Descriptors: Dental impression materials; Dental impression technique; Fixed partial denture.
Electromyography has been used to evaluate the performance of the peribuccal musculature in mastication, swallowing and speech, and is an important tool for analysis of physiopathological changes affecting this musculature. Many investigations have been conducted in patients with auditory and speech deficiencies, but none has evaluated the musculature responsible for the speech. This study compared the electromyographic measurements of the superior and inferior fascicles of the orbicularis oris muscle in patients with profound bilateral neurosensorial hearing deficiency (deafness) and healthy volunteers. Electromyographic analysis was performed on recordings from 20 volunteers (mean age of 18.5 years) matched for gender and age. Subjects were assigned to two groups, as follows: a group formed by 10 individuals with profound bilateral neurosensorial hearing deficiency (deaf individuals) and a second group formed by 10 healthy individuals (hearers). Five clinical conditions were evaluated: suction, blowing, lip projection and compression, and production of the syllable "Pa". It was found that the deaf patients presented muscle hyperactivity in all clinical conditions, and that the inferior fascicle of the orbicularis oris muscle showed higher electromyographic activity rates, suggesting the need for a hearingspeech treatment with emphasis on oral motricity.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.