Conventional and digital maxillary occlusal record for the manufacture of complete-arch implant-supported fixed prostheses: randomized controlled clinical trial.

OBJECTIVES: To evaluate the trueness of the digital maxillary occlusal records in comparison with the conventional records for the fabrication of complete-arch implant-supported fixed prostheses. MATERIALS AND METHODS: This randomized controlled clinical trial followed the recommendations of the CONSORT statement. Twenty participants who used a mandibular interim complete-arch fixed prosthesis and conventional complete maxillary dentures were included in the study. The participants were randomized into two types of maxillary occlusal records: conventional (COR) and digital (DOR) (TRIOS; Shape A/S). After fabricating the prostheses, the distribution and number of occlusal contact points, and the time taken to obtain the maxillary occlusal record and work model were evaluated. Descriptive analysis was used to evaluate the distribution of occlusal contact points. The Wilcoxon test was employed for assessing the number of occlusal contact points, while the Mann-Whitney U test was used for the time taken to obtain the working casts and the maxillary occlusal record and occlusal adjustment times (p < 0.05). RESULTS: There was a similarity in the jaw relation recording methods regarding the distribution of occlusal contact points. There was no difference in the number of occlusal contact points between the anterior (p = 0.439) and posterior (p = 0.227) teeth. No relationship was observed between the distribution and number of occlusal contact points (COR, p = 0.288; DOR, p = 0.183). DOR required less occlusal and clinical adjustment time, on the other hand more laboratory and total workflow time than COR (p < 0.001). CONCLUSION: The DOR may be an option for obtaining the functional space necessary for the assembly of teeth in complete-arch implant-supported fixed prostheses; however, it requires more working time. CLINICAL RELEVANCE: The digital occlusal recording method can be used to assess the interocclusal space for the virtual tooth setup of a complete-arch implant-supported fixed prosthesis.

Assessment of occlusal ridges in premolar teeth before and after dental treatment in equines / [Avaliação das cristas oclusais de dentes pré-molares antes e após o tratamento dental em equinos]

Occlusal ridges of equines appeared in the evolutionary process of the species to increase its capacity of grazing and trituration. The difference in hardness of dental tissues (cementum, dentin, and enamel) and masticatory pressure on the occlusal surface of the hypsodont tooth promote the appearance of sharp occlusal ridges. The aim of this study was to measure and compare the height of the occlusal ridges (HOR) of the fourth premolar (Triadan 408) before and after odontoplasty. Ten Mangalarga Marchador mares aged 5 to 12 years, under extensive management, were evaluated by measuring the HOR in Triadan 408, using plaster models before, immediately after (D0), 15 days (D15) and 50 days (D50) after odontoplasty. Immediately after the procedure the HOR was only 21.9% of the HOR before the occlusal equilibration; however, in 15 days after odontoplasty, 65.9% of HOR was already reestablished and 80.3% after 50 days of the procedure. HOR in the buccal side resurfaced before the lingual HOR, suggesting a higher masticatory pressure of these buccal points. Results of the present study indicate that 15 days after the dental treatment, equines already have food trituration capacity, since HOR is apparent on the occlusal surface of the premolars that underwent odontoplasty.

Cristas oclusais de equinos surgiram no processo evolutivo da espécie para aumentar sua capacidade de pastejo e trituração. A diferença na dureza dos tecidos dentários (cemento, dentina e esmalte) e a pressão mastigatória na superfície oclusal do dente hipsodonte promovem o aparecimento de cristas oclusais afiadas. O objetivo deste estudo foi medir e comparar a altura das cristas oclusais (HOR) do quarto pré-molar (Triadan 408) antes e após a odontoplastia. Dez éguas Mangalarga Marchador de cinco a 12 anos, sob manejo extensivo, foram avaliadas pela mensuração da HOR no Triadan 408, utilizando-se modelos de gesso antes, imediatamente após (D0), 15 dias (D15) e 50 dias (D50) após a odontoplastia. Imediatamente após o procedimento, a HOR era de apenas 21,9% da HOR antes do equilíbrio oclusal; entretanto, em 15 dias após a odontoplastia, 65,9% da HOR já estava restabelecida e 80,3% após 50 dias do procedimento. HOR na face vestibular ressurgiu antes da HOR lingual, sugerindo maior pressão mastigatória nestes pontos vestibulares. Os resultados do presente estudo indicam que 15 dias após o tratamento odontológico, os equinos já apresentam capacidade de trituração dos alimentos, uma vez que a HOR é aparente na superfície oclusal do pré-molar que foi submetido à odontoplastia.