IADR Abstract Archives
What lies beneth: Three dimensional evaluation of Secondary Dentin
Objectives: Dentin consists of a primary layer produced during tooth formation and a second layer- secondary dentin (SD) which forms upon tooth eruption and throughout life. The SD layer is preserved even in eroded teeth and has been previously established as a parameter for age by histology, however the effect of attrition on SD formation remains under constant debate. In the current study we aim to establish non-invasive, direct-virtual analysis of the SD layer based on its radiolucent nature as it appears in micro-computerized tomography (μCT).
Methods: Ninety lower second premolars were scanned from the Hamann-Todd Osteologic Collection of the Cleveland Museum. Scans were performed using a Skyscan 1178 μCT (Bruker) at a 17.2-micron resolution. Analysis was done using Amira (FEI), and statistics using SPSS (IBM). Histology was conducted using traditional methods and Paragon staining (Sigma) for SD conformation.
Results: Histological comparison to virtual analysis showed high correlation, validating μCT analysis as a valid tool for SD identification. An age to SD scale was established while controlling variables of age, gender, ethnicity, tooth type and attrition. SD was found to be highly correlative with age, and together with pulp and dentin volume analysis increased the accuracy of age estimation (R=0.818). Three-dimensional analysis of SD formation indicated the constrained effect of occlusal attrition, and the negligible effect of interproximal attrition.
Conclusions: Utilizing SD evaluation, we may gain insights relevant for operative dentistry while also crossing over to forensic dentistry and paleo-odontology - two fields that may gain from a non-invasive analysis allowing accurate age estimation.
Methods: Ninety lower second premolars were scanned from the Hamann-Todd Osteologic Collection of the Cleveland Museum. Scans were performed using a Skyscan 1178 μCT (Bruker) at a 17.2-micron resolution. Analysis was done using Amira (FEI), and statistics using SPSS (IBM). Histology was conducted using traditional methods and Paragon staining (Sigma) for SD conformation.
Results: Histological comparison to virtual analysis showed high correlation, validating μCT analysis as a valid tool for SD identification. An age to SD scale was established while controlling variables of age, gender, ethnicity, tooth type and attrition. SD was found to be highly correlative with age, and together with pulp and dentin volume analysis increased the accuracy of age estimation (R=0.818). Three-dimensional analysis of SD formation indicated the constrained effect of occlusal attrition, and the negligible effect of interproximal attrition.
Conclusions: Utilizing SD evaluation, we may gain insights relevant for operative dentistry while also crossing over to forensic dentistry and paleo-odontology - two fields that may gain from a non-invasive analysis allowing accurate age estimation.