Reuse of healing abutments : ethical, biological and professional training implications

The aim was to estimate the prevalence of reuse of healing abutments, the methods used in disinfection and to analyze the reasons that lead to the reuse of these components by professionals who work in rehabilitation with dental implants. For this, an

Avaliação da resistência de união de restaurações de resina composta com diferentes sistemas adesivos, em dois tempos de armazenamento

Water degradation of dentin bonding agents may influence bond strength in composite resin restorations after some periods of time. The aim of this study was to evaluate the influence of storage time with thermociclyng and type of dentin bonding agents used on the composite resin restorations microshear bond strength. Twenty molars were used and divided into two evaluation periods (24 hours and 6 months, plus thermocycling). Each tooth had its occlusal surface dentin exposed, and received three units of test made of Flow composite resin, with the following adhesive systems: Scotchbond multipurpose (3M/ESPE – group 1), Clearfi l SE Bond (Kuraray – group 2) and Adper Single Bond (3M/ESPE – group 3). Subsequently to the microshear bond strength testing, data were analyzed by ANOVA, Tukey and Student t tests (α = 0,05). The results showed that there were no differences between Scotchbond multipurpose, ClearFil SE Bond and Adper Single Bond on microshear bond strength after 24 hours of storage. After 6 months, ClearFil SE Bond demonstrated higher resistance than Scotchbond multipurpose. Scothtchbond multipurpose presented a reduction in its performance when 6 months passed. ClearFil SE Bond and Adper Single Bond suffered no influence resultant from the storage period.A degradação hidrolítica dos adesivos dentinários pode influenciar a resistência de união das restaurações de resina composta ao longo do tempo. O objetivo deste trabalho é avaliar a influência do tempo de armazenamento associada à termociclagem e do tipo de adesivo dentinário empregado sobre a resistência de união de restaurações de resina composta. Foram utilizados 20 molares hígidos, os quais foram divididos em 2 tempos de avaliação (24 horas e 6 meses + termociclagem). Cada dente teve a dentina relativa à superfície oclusal exposta, a qual recebeu 3 corpos de prova de resina Flow com os sistemas adesivos: Scotchbond multiuso (3M/ESPE - Grupo 1), ClearFil SE Bond (Kuraray - Grupo 2) e Adper Single Bond (3M/ESPE - Grupo 3). Após o teste de microcisalhamento, os dados foram analisados estatisticamente pelos testes ANOVA, Tukey e t-student (?=0,05). Os resultados mostraram que os adesivos Scotchbond multiuso, ClearFil SE Bond e Single Bond não apresentaram diferenças na resistência de união em 24 horas de armazenamento. Após 6 meses, o adesivo ClearFil SE Bond obteve resistência superior ao Scotchbond multiuso. O adesivo Scotchbond multiuso sofreu redução na resistência de união após 6 meses de armazenamento. Os adesivos ClearFil SE Bond e Single Bond não sofreram influência do tempo de armazenamento e da termociclagem

Shear bond strength of composite resin luted in bovine teeth by different luting techniques

The aim of this study was to evaluate Z250 (3M/ESPE) composite resin shear bond strength, luted to bovine enamel using Zync Phosphat, Glass Ionomer cement and resin luting cement with 3 different composite resin superficial treatment. It was made 75 specimens of bovine incisors and composite resin, that was conformed in a 3mm matrix, lightcured during 20 seconds. The specimens were devided in 5 groups: Group 1 – luted with Zync Phosphat; Group 2 – luted with Glass Ionomer cement; Group 3 – luted with resin luting cement; Group 4 – luted with resin luting cement and composite resin etching/bonding; Group 5 – luted with resin luting cement and composite resin Al2O3 microetching. The specimens were tested in Universal testing machine, throught shear bonding strength, with 0,5 mm/minute speed. Results were statistically analysed by ANOVA and Tukey tests (α= 0,05), that showed Group 4 (resin luting cement and composite resin etching/bonding) has being statistically superior from the others; Group 3 (Resin luting cement) and Group 5 (Resin luting cement and composite resin microetching) did not show statistically significant difference from each other; Group 1(Zync Phosphat) and Group 2 (GIC) showed lowest bond strength and did not show statistically significant difference from each other. The best demonstrated composite resin cementation technique was resin luting cement and restorations etching/bonding, in relation to shear bond strength

A successful approach to conrol burning mouth syndrome using matricaria recutita and cognitive therapy

The burning mouth syndrome (BMS) has no specific clinical and laboratory signs. Its etiology is yet to be elucidated, but it is considered to be affected by multifactorial, psychological, and local and systemic factors. This condition is considered of great morbidity, and the main complaint of patients maybe associated with xerostomia, thirst, and altered taste. The present study aims to report two cases of BMS and to evaluate the outcome of cognitive therapy (CT) plus phytotherapy in the control of BMS. The patients were female, Caucasian, and aged between 58 and 69 years. The most BMS-affected anatomical parts were the lips and the tongue. In the clinical approach, oral and systemic evaluation, and disease management with CT plus chamomile tea were done. The patients were reassured, and their response to therapy one year after was found to be excellent despite few exacerbations in periods of great emotional stress. Thus, we conclude that psychological treatment is vital in the management of BMS, as CT, along with Matricaria recutita phytotherapy, displayed excellent results in the control of BMS

Resistência à fratura de fragmentos dentários colados com diferentes materiais e técnicas

OBJECTIVE: This study evaluated in vitro the shear bond strength of experimentally fractured human tooth fragments reattached with different adhesive materials and retentive techniques. METHODS: Forty-eight sound mandibular incisors were randomly divided into 6 groups (n=8). Their incisal edges were cut off in 5 groups, representing an enamel-dentin fracture. Intact teeth were used as control (Group 1). The fragment edges were reattached with adhesive system (Scotch Bond Multipurpose – 3M ESPE) (Group 2), adhesive system and composite resin (ICE – SDI) (Group 3), adhesive system and composite resin with circumferential bevel (Group 4), adhesive system and composite resin with internal dentin groove (Group 5), and adhesive system and composite resin with the circumferential bevel and internal dentin groove (Group 6). Shear bond strength was determined in a universal testing machine. Fracture modes were identified by light microscope. Kruskal-Wallis was used to analysis resistance to fracture and fracture patterns. RESULTS: The results showed statistically significant differences (p<0.05) among groups. The intact teeth (Group 1) showed higher fracture resistance than the other groups. Groups 2 and 6 did not differ and were statistically superior to other techniques. Group 4 presented statistically higher than in Group 5, which in turn was more resistant than Group 3. CONCLUSIONS: None of the fragment reattachment techniques was able to achieve the strength of sound teeth. Fragments reattached only with adhesive system or with adhesive system and composite resin with the circumferential bevel and internal dentin groove showed the best performance for resistance to fracture.INTRODUÇÃO: Este estudo analisou in vitro a resistência à fratura por cisalhamento de fragmentos dentários de incisivos inferiores humanos colados por diferentes técnicas. MÉTODOS: 48 incisivos inferiores hígidos foram divididos aleatoriamente em 6 grupos n=8). Cinco grupos tiveram os seus bordos incisais seccionados. Dentes hígidos foram usados como controle (Grupo 1). Os fragmentos dentários foram colados com sistema adesivo (Scotch Bond Multipurpose – 3M ESPE) (Grupo 2), sistema adesivo e resina composta (ICE – SDI) (Grupo 3), sistema adesivo e resina composta com técnica de bisel (Grupo 4), sistema adesivo e resina composta com técnica de canaleta (Grupo 5), sistema adesivo e resina composta com bisel e canaleta (Grupo 6). Todos os grupos foram submetidos ao ensaio de cisalhamento para avaliação da resistência à fratura dos fragmentos e os padrões de fratura foram identificadas em microscópio. A análise dos dados de resistência à fratura e dos padrões de fratura foi feita através de teste não-paramétrico de Kruskal-Wallis. RESULTADOS: Os resultados encontrados demonstraram diferenças estatisticamente significativas (p<0,05) entre os grupos. Dentes hígidos (Grupo 1) apresentaram maior resistência à fratura do que os demais grupos. Os Grupos 2 e 6 não diferiram entre si, e foram estatisticamente superiores às demais técnicas. O Grupo 4 apresentou resultados estatisticamente superiores ao Grupo 5, que por sua vez foi mais resistente do que o Grupo 3. CONCLUSÃO: Nenhuma das técnicas de colagem de fragmento foi capaz de atingir a resistência dos dentes hígidos. As técnicas de colagem de fragmento realizadas apenas com sistema adesivo ou com resina composta com a técnica de canaleta no fragmento associada ao bisel foram aqueles que apresentaram melhores desempenhos em relação à resistência a fratura

Hot air stream reduces cytotoxicity of light-cured calcium hydroxide based cements

The light-cured calcium hydroxide based cements have incomplete polymerization and unconverted monomers can cause pulp cell damage. The aim of this study was to evaluate the influence of a warm and hot air stream on the cytotoxicity of light-cured calcium hydroxide based cements. The materials Dycal (conventional cement), Biocal, Hidrox-Cal, and Ultra-Blend Plus (light-cured calcium hydroxide cements) were submitted to cytotoxicity analysis after polymerization, without vs. with previous heat treatment with a warm (37°C) and a hot (60°C) air stream. Following polymerization, cements were maintained in culture medium for 24 hours and 7 days, and subjected to the MTT test. Data were analyzed using analysis of variance (ANOVA) followed by post-hoc Student-Newman-Keuls (<0.05). The results indicated significant differences between the materials according to their composition, i.e., light-cured cements treated with a jet of warm air showed similar cytotoxicity levels to those observed for conventional cement, suggesting that they may be considered alternatives in cases requiring pulp-capping treatment. Application of a hot air stream reduced cytotoxicity of materials tested