ABSTRACT
OBJECTIVES: The aim of this study was to evaluate the intrapulpal temperature variation after bleaching treatment with 35 percent hydrogen peroxide using different sources of activation. MATERIAL AND METHODS: Twenty-four human teeth were sectioned in the mesiodistal direction providing 48 specimens, and were divided into 4 groups (n=12): (G1) Control - Bleaching gel without light activation, (G2) Bleaching gel + halogen light, (G3) Bleaching gel + LED, (G4) Bleaching gel + Nd:YAG Laser. The temperatures were recorded using a digital thermometer at 4 time points: before bleaching gel application, 1 min after bleaching gel application, during activation of the bleaching gel, and after the bleaching agent turned from a dark-red into a clear gel. Data were analyzed statistically by the Dunnet's test, ANOVA and Tukey's test (a=0.05). RESULTS: The mean intrapulpal temperature values (ºC) in the groups were: G1: 0.617 ± 0.41; G2: 1.800 ± 0.68; G3: 0.975 ± 0.51; and G4: 4.325 ± 1.09. The mean maximum temperature variation (MTV) values were: 1.5ºC (G1), 2.9ºC (G2), 1.7ºC (G3) and 6.9ºC (G4). When comparing the experimental groups to the control group, G3 was not statistically different from G1 (p>0.05), but G2 and G4 presented significantly higher (p<0.05) intrapulpal temperatures and MTV. The three experimental groups differed significantly (p<0.05) from each other. CONCLUSIONS: The Nd:YAG laser was the activation method that presented the highest values of intrapulpal temperature variation when compared with LED and halogen light. The group activated by LED light presented the lowest values of temperature variation, which were similar to that of the control group.
Subject(s)
Humans , Body Temperature/drug effects , Dental Pulp/drug effects , Hydrogen Peroxide/therapeutic use , Light , Oxidants/therapeutic use , Tooth Bleaching/methods , Gels , Hydrogen Peroxide/administration & dosage , Hydrogen Peroxide/radiation effects , Lasers, Solid-State/therapeutic use , Lighting/instrumentation , Materials Testing , Oxidants/administration & dosage , Oxidants/radiation effects , Thermometers , Time FactorsABSTRACT
Retentores intra-radiculares metálicos fundidos podem ser obtidos através de técnicas de moldagem e modelagem. Freqüentemente verifica-se um espaço entre o pino radicular e o remanescente do material obturador endodôntico (Falleiros, Collesi, 1988), viabilizando a contaminação da região periodontal, via canal acessório ou lateral não preenchido pelo material obturador (Shillingburg, Kessler, 1991).O objetivo deste trabalho foi comparar, radiograficamente, o espaço residual apical entre retentores intra-radiculares metálicos fundidos, confeccionados por meio das técnicas direta (modelagem) e indireta (moldagem), e o remanescente de material obturador do canal radicular. Para o levantamento dos dados deste trabalho, foram enviados para Cirurgiões-dentista questionário e filme radiográfico periapical duplo para a tomada radiográfica após cimentação do retentor intra-radicular e o espaço residual foi mensurado no software Image Tool 1.27. Houve diferença estatisticamente significante entre as técnicas de confecção dos retentores intra-raduculares. Verificou-se que o espaço residual apical foi menor nos retentores obtidos pela técnica de moldagem. Concluiu-se que a existência do espaço residual apical foi maior na técnica de modelagem que na de moldagem