Determination of root dentin and cementum micro hardness

Correspondence to: Giuseppe Alexandre Romito Faculdade de Odontologia – Universidade de São Paulo. Disciplina de Periodontia Av. Lineu Prestes, 2227 Cidade Universitária São Paulo S.P. Brazil CEP 05508-900 Telefone: 55 (11) 5084-9949 ou 55 (11) 8174-3639 e-mail: [email protected] Abstract Vickers micro hardness was assessed on root dentin and cementum in 30 canines obtained from the Periodontics Discipline tooth bank. Crown and cervical portion of the root were discarded by a transverse section situated 3mm, apically, from the cemento-enamel junction on the buccal surface, thus obtaining the root specimen. On root dentin, mean micro hardness values were obtained for 3 regions: (DR1) from 0.05 to 0.1 mm of the cemento dentin junction – 30.64 VHN; (DR2) from 0.3 to 0.5 mm of the cemento dentin junction – 56.92 VHN and (DR3) from 0.8 to 1.0 mm of the cemento dentin junction – 32.70 VHN. After statistical analysis (Variance Analysis test, p < 0,05), we conclude that micro hardness at the DR2 region was statistically greater than that at the DR3 region which was, in turn, greater than that at the DR1 region. The mean micro hardness of cementum was 19.70 VHN.