Determination of the dynamics of restored teeth by 3D electronic speckle pattern interferometry

Background and Objectives The difficulties typically encountered in studying the effects of restorations on tooth reinforcement are often due to the 3‐dimensional (3D) nature of deformation. Therefore, electronic 3D‐Speckle‐Interferometry (3D‐ESPI) was used to assess the impact of different restorative materials on the deformation of teeth. Study Design/Materials and Methods Small and large MOD‐preparations in extracted premolars were restored with gold inlays, ceramic inlays, composite resin inlays, amalgam, or composite resin. The restorations and cusps were loaded (90 N) and the deformation was assessed by 3D‐ESPI. Results Teeth with small restorations were deformed only slightly and the differences between the materials were minimal (P>0.05). In contrast, teeth with large restorations displayed material‐specific deformation patterns: (a) all materials led to decreased deformation as compared with unfilled teeth, (b) elastic materials caused only local deformation, (c) non‐adhesive materials resulted in translation of the restoration and marginal discrepancies, (d) adhesive inlays brought about increased deformation of the luting resin composite, (e) loading of the cusps caused higher deformation than loading of the restorations, and (f) bonded restorations stabilized the cusps. Conclusions The results show that the deformation pattern of restored teeth is material‐specific but the extent of deformation is primarily limited by the remaining tooth substance. Lasers Surg. Med. 34:300–309, 2004. © 2004 Wiley‐Liss, Inc.