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Simultaneous irradiation of multiple flasks may have deleterious effects on the polymerization of microwave cured-acrylic resins. This study evaluated the effect of the number and position of flasks in the monomer release, Knoop hardness and porosity of a microwave-cured acrylic resin. Samples were made of Acron MC(R) (AMC, GC Dent. Ind. Corp.) processed at 500 W. The following associations of the number and position of the flasks were tested: one simple flask centrally placed on the turning plate (I, control); two flasks, one in the centre (IIa) and the other peripherally placed in the plate (IIb); two flasks centrally, one above (IIIa) and the other below (IIIb). The processing time varied according to the number of flasks: 3 or 4.5 min for one or two flasks, respectively. For monomer release, each specimen (n = 12) was put in an assay glass tube containing 6 mL of deionized water that was changed daily. Monomer levels were obtained by spectrophotometry at 206 nm. For hardness test (n = 10), 12 indentations were made in the surface of each specimen. Immersing the polished specimens in permanent ink and counting the porous in a stereo light microscope verified the porosity. Monomer release was significant before 24 h: GI = 263.1(153.3)a, GIIa = 236.9(180.2)a, GIIb = 441.5(446.2)a, GIIIa = 1216.6(857.9)b. Tukey test showed no statistically significant differences among the groups for porosity and hardness. Monomer release was affected by the position of the flask (P < 0.05).

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ResumoAs próteses parciais removíveis (PPRs) são bastante requisitadas no intuito de repor os dentes naturais perdidos e estruturas associadas. Uma correta avaliação, diagnóstico diferencial e planejamento detalhado devem ser realizados antes da confecção desse aparelho. Em alguns casos, o descaso no cirurgião dentista dá margem ao alto índice se insucesso desse tipo de trabalho, pois é delegada para o técnico em prótese dentária a parte mais importante desse processo, que é o planejamento. Objetivo: Realizar a análise comparativa do processo de planejamento de Próteses Parciais Removíveis (PPR) Classe I de Kennedy desenvolvido por laboratórios de prótese dental de Salvador. Metodologia: Três tipos de modelos Classe I de Kennedy em gesso tipo III foram confeccionados e enviados a 10 técnicos de laboratório para planejamento de uma PPR a grampo. Posteriormente, os modelos foram avaliados segundo critérios pré-estabelecidos. Resultados: A confecção da PPR, no que diz respeito a localização da base da sela, localização das margens da prótese, braços de oposição foi bem executada, porém foram detectadas limitações na indicação dos grampos e dos tipos de sela adequados para cada caso simulado. Além disso, foi possível perceber que o uso do delineador foi ignorado por todos os protéticos visitados. Conclusão: Foi possível perceber com este estudo que os técnicos avaliados não estão aptos a planejar o posicionamento e indicação dos grampos ou localização dos pilares. Palavras-chave:Planejamento; Prótese Parcial Removível; Técnico em Prótese Dentária. EVALUATION OF DENTAL TECHNICIAN'S PLANNING IN MODELS CLASS I OF KENNEDY AbstractPartial removable dentures (PRD) are frequently requested to replace lost teeth and associated structures. A correct evaluation, diagnosis and a detailed planning must be done before the prosthesis fabrication. In some cases, the negligence of the dentist leads to a high failure index, because the planning is transmitted to the dental technician. Purpose: To compare the treatment planning for Kennedy Class I RPD made by ten dental laboratories from Salvador. Método: Three types of cast Kennedy Class I RPD were performed and sent to dental laboratories for the planning of a PRD. Then, planned casts were examined following established criteria. Resultados: The location and borders of the base were well done, but indication of the clasp and kind of base were not. The pararelometer was not used by any technician. Conclusão: Technicians are not able to indicate pillars and plan location and indication of RPD clasps.

| Objective: The objective of this workwas to evaluate the influence of different methods of surface treatment on glass fiber posts with respect to their bond strength with the composite resin. Method: Twenty-four pre-fabricated posts were randomly divided into three groups (n= 8) according to the chosen surface treatment. Control Group-surface treatment with 37% phosphoric acid etching and silanization. Group 2 -conditioned with 10% fluoridric acid and silanization. Group 3 -sandblasting for 10 seconds and silanization. The specimens were obtained using the stainless steel matrix made for this study and were maintained in absolute humidity at 37 ° C for 48 hours and then subjected to the PUSH-OUT test on the test machine. Results: The results showed that the aluminium oxide blasting treatment of aluminum and silane (12.24 MPa) (G3) had statistically significant difference when compared to the treatment of hydrofluoric acid and silane (G2) (8.03 MPa) (p <0, 05). The predominant fracture type was cohesive of the composite resin (68.75%) and only a mixed fracture (2.08%) was observed. Conclusions: Thus, it is concluded that the blasting treatment of aluminum oxide and silane can be used as a surface treatment on the glass fiber post.