909 Physical Properties of the Enamel of Deciduous and Permanent Teeth

Friday, March 23, 2012: 2 p.m. - 3:15 p.m.
Presentation Type: Poster Session
J.M. GOMES-SILVA, Faculdade de Odontologia de Ribeirão Preto-University of Sao Paulo, Ribeirão Preto, Brazil, C. TORRES, USP, Ribeirão Preto, Brazil, M.A. MENEZES-OLIVEIRA, Uniube, Uberaba-Minas Gerais, Brazil, L.C. PARDINI, University of Sao Paulo, Ribeirao Preto-SP, Brazil, M.C. BORSATTO, FORP - USP, Ribeirão Preto, Brazil, and R.G. PALMA-DIBB, Departamento de Odontologia Restauradora, Faculdade de Odontologia de Ribeirao Preto, Ribeira Preto, SP, Brazil
Objectives: There is still little research and information on the precise composition and the micromorphology of the enamel of deciduous teeth, and the existing literature reveals controversial findings. The results of studies in permanent teeth are frequently extrapolated to deciduous teeth, and the majority of works explores these substrates alone. It is thus necessary to know the composition and structure of the enamel of deciduous teeth and determine in which ways this tissue actually differs from the enamel of permanent teeth. Comparison of these substrates under different aspects is fundamental to establish preventive and restorative protocols, as well as materials and techniques that are specific and effective for deciduous and permanent teeth. Therefore, the aim of the present in vitro study was to perform a comparative analysis of the enamel of deciduous and permanent teeth.

Methods: The physical properties were evaluated by the tests:  Permeability (n=12), Microhardness (n=12), Radiodensity (n=10) and Ultimate Tensile Strength (n=15). Data distribution and homogeneity were analyzed. Data distribution was normal and homogenous. Thus, one-way analysis of variance (type of substrate) was used for the Permeability; two-way analysis of variance (type of substrate and depth) was used for the Microtensile Bond Strength test (p<0.05); data from Radiodensity and test were analyzed using the Student’s t-test.

Results: Considering the limitations of an in vitro investigation, the findings revealed that with respect to the physical properties, the enamel of deciduous teeth presented greater permeability and radiodensity and lower ultimate bond strength and substrate when compared with the enamel of permanent teeth.

Conclusions: Therefore, the enamel of deciduous teeth presented different physical properties compared to the permanent teeth.

Keywords: Assessment, Enamel, Physical, Structure and Surfaces