Cemental tear: A risk factor in periodontal attachment loss
The phenomenon of cemental tear has been observed within unexposed as well as exposed cementum and has been described as a complete separation along the cemento-dentinal border or a partial split within the cementum along an incremental line. The objective of this retrospective study was to evaluate the influence of cemental tear as a risk factor in periodontal attachment loss.
Seventeen extracted, single-rooted teeth showing loss of attachment and having one cemental tear surface and one intact surface were examined. The teeth were stained with 0.1% toluidine blue to facilitate periodontal attachments. The teeth then were examined using a light microscope with incident light. On each tooth, loss of attachment was measured along the long axis of the root from the cementoenamel junction to the most coronal level of the periodontal ligament on intact as well as on defective surfaces. Cemental tear surfaces demonstrated a significantly greater loss of attachment than opposite intact surfaces (p < 0.00001). All measurements were carried out by one investigator. In one specimen, the cemental tear fragment was still attached to the apical root fiber after extraction. This specimen was immediately fixed in 10% buffered formalin and processed for light microscopy. Histological examination clearly revealed that the split between the root and the fragment had occurred along the cemento-dentinal border.
The authors concluded that this study demonstrated that cemental tear significantly influences loss of attachment, seems to represent an underdiagnosed phenomenon, and should be considered a possible etiologic factor in localized rapid periodontal breakdown. [I.S.]
Leknes, K.N.,T. Lie, and K.A. Selvig, J Periodont, 67:583, 1996