Effect of ultrasonic and sonic activation of root canal sealers on the push-out bond strength and interfacial adaptation to root canal dentine.

AIM: To evaluate the effect of ultrasonic and sonic activation of two root canal sealers on interfacial adaptation and push-out bond strength (BS) to root canal dentine. METHODOLOGY: The root canals of seventy-eight roots of maxillary canines were prepared with NiTi rotary instruments under irrigation with 2.5% NaOCl and 17% EDTA. Canals were filled by lateral condensation of gutta-percha and AH Plus (n = 39) or MTA Fillapex (n = 39). Three subgroups (n = 13) were formed according to sealer activation: no activation (NA), sonic activation (SA, 20 s) and ultrasonic activation (US, 20 s). In three specimens of each subgroup, 0.1% rhodamine B was added to the sealer. Three 1-mm-thick slices were obtained from each root third. The first and second were used for push-out BS test and the third for a qualitative analysis of interfacial adaptation (gaps) and voids by confocal laser scanning microscopy (CLSM). Intratubular penetration of rhodamine B-labelled sealer was also assessed by CLSM. Data were analysed by two-way anova and Tukey's test (α = 0.05). RESULTS: AH Plus (2.58 ± 1.21) had higher push-out BS than MTA Fillapex (1.45 ± 0.71) (P = 0.000). UA (2.64 ± 1.44) had higher BS (P = 0.000) than NA (1.58 ± 0.73) and SA (1.83 ± 0.85), which did not differ significantly from each other (P = 0.3303). The coronal third had higher BS (2.48 ± 1.49) than the middle (2.08 ± 0.94) (P = 0.0003) and apical (1.48 ± 0.58) (P = 0.00) thirds. For both sealers, UA was associated with a more homogeneous filling material with better interfacial adaptation and greater quantity, density and length of tags in dentinal tubules. When UA was used, the tags had similar quantity, density and length to those formed without activation, but interfacial gaps and voids were observed. CONCLUSION: Ultrasonic activation was associated with higher BS values, deeper intratubular penetration and greater interfacial adaptation to root dentine than sonic activation and no activation techniques, AH Plus had higher BS values than MTA Fillapex irrespective of the type of activation.

Tipo e freqüência de alteraçöes dentárias e periodontais em cäes na regiäo de Jaboticabal, SP / Type and frequency of dental diseases and disorders in dogs in the region of Jaboticabal, SP

Realizou-se levantamento das alteraçöes periodontais, dentárias e da oclusäo dental espontâneas em 215 cäes necropsiados ou que morreram por razöes diversas, no Hospital Veterinário da Faculdade de Ciências Agrárias e Veterinárias da UNESP, Jaboticabal. As alteraçöes periodontais, identificadas por exame clínico, foram tabuladas considerando raça, dieta, faixa etária e sexo. Os índices gengival e de placa foram aplicados a todos os animais e análise radiográfica foi realizada quando necessária. O levantamento epidemiológico revelou elevada freqüência de alteraçöes relacionadas à presença de placa bacteriana e de alteraçöes gengivais. Observou-se também agravamento das alteraçöes com o avançar da idade, evidenciado radiograficamente. Os animais alimentados somente com raçäo apresentaram menor freqüência de alteraçöes relacionadas aos índices gengival e de placa, em relaçäo àqueles alimentados com dieta caseira. Näo se observou diferença entre sexos quanto às alteraçöes dentárias

Microbiota saprófita associada à doença periodontal em cäes / Oral flora associated with periodontal disease in dogs

Realizou-se um estudo sobre a microbiota saprófita associada à doença periodontal espontânea em cäes com o objetivo de identificar as bactérias anaeróbias predominantes nas lesöes. Com auxílio de cureta odontológica, amostras colhidas diretamente do espaço subgengival foram semeadas em meio CDC (Central for Disease Control) para anaeróbios e incubadas, em anaerobiose, a 37§C, por sete dias. A caracterizaçäo das colônias foi realizada por meio da morfologia e do teste bioquímico (Sistema API 20A). Identificaram-se os seguintes gêneros: Prevotella spp., Bacteroides spp., Propionibacterium spp., Gemella spp., Actinomyces spp., Eubacterium spp. e Porphyromonas spp