Physicochemical properties of dentinogenesis imperfecta with a known DSPP mutation

Aim: To investigate the chemical and mechanical properties of teeth affected by a 1-bp deletion (c.2688delT) in the DSPP gene. Methods and Materials: Maxillary first premolars were extracted from the affected individual at age 9 years due to the orthodontic reason for crowding. A sample was imbedded in epoxy resin and sectioned buccolingually, after micro-computerized tomography (mu CT) images were taken. Scanning Electron Microscopy (SEM), Energy Dispersive Spectrometry (EDS) and Vickers microhardness testing were also performed. Results: mu CT reconstruction and analysis showed an irregularly obliterated pulp chamber and an extremely small pulpal volume in the DGI-II sample. The mineral density and microhardness scores were smaller in the dentin of the DGI-II sample compared to the wild-type. Mg content was lower in the dentin of the DGI-II sample compared to the wild-type. Conclusion: This study shows that dentin affected by a 1-bp deletion in DSPP has a reduced mineral density, diminished microhardness and reduced Mg content.