IADR Abstract Archives
Which Digital Method Should We Used to Register Implant Position?
Objectives: Background: Traditionally dentists register implants’ position in patients’ mouth by making impression and pouring stone models. With the advent of CAD/CAM (computer-aided design and manufacture) dentistry, cone-beam computed tomogram (CBCT), intraoral and model scanning may also be used to register implants’ position digitally.
Objectives: This pilot study aims to determine the accuracy of implant apex position registered by CBCT, intra-oral and model scanning.
Methods: An implant was inserted into the maxillary central incisor region of a manikin. A cube of 1 cm×1 cm×1 cm dimensions was machine-milled in a heat-cured acrylic stent which seated on the teeth of this manikin. Mesio-occlusal-buccal corner of this cube was selected to be the origin with Cartesian (x, y, z)-coordinates defined in both physical and various virtual domains. Coordinate-measuring machine (CMM) was used to measure the coordinates of implant apex physically that served as the gold-standard. CBCT of the manikin was taken (iCAT classic) (T1). The manikin was scanned by an intraoral scanner (3M True-definition) (T2). An open-tray impression was made on the manikin and poured into a model. This model (T3) and the manikin (T4) were scanned by a model scanner (Imetric). Data were imported into Meshlab and the coordinate of the implant apex were measured in 3D Slicer. The difference in the implant apex coordinates between the gold-standard and the CBCT/optical scanning was expressed in root-mean-square (RMS).
Results: With regard to the position of implant apex, the RMS distance of T1 from the control was 0.84mm. The RMS of T2, T3 and T4 were 0.28mm, 0.95mm and 0.29mm respectively.
Conclusions: Optical scanning of the model may be a radiation–free alternative to register implant position. Further studies are needed with sufficient sample size.
Objectives: This pilot study aims to determine the accuracy of implant apex position registered by CBCT, intra-oral and model scanning.
Methods: An implant was inserted into the maxillary central incisor region of a manikin. A cube of 1 cm×1 cm×1 cm dimensions was machine-milled in a heat-cured acrylic stent which seated on the teeth of this manikin. Mesio-occlusal-buccal corner of this cube was selected to be the origin with Cartesian (x, y, z)-coordinates defined in both physical and various virtual domains. Coordinate-measuring machine (CMM) was used to measure the coordinates of implant apex physically that served as the gold-standard. CBCT of the manikin was taken (iCAT classic) (T1). The manikin was scanned by an intraoral scanner (3M True-definition) (T2). An open-tray impression was made on the manikin and poured into a model. This model (T3) and the manikin (T4) were scanned by a model scanner (Imetric). Data were imported into Meshlab and the coordinate of the implant apex were measured in 3D Slicer. The difference in the implant apex coordinates between the gold-standard and the CBCT/optical scanning was expressed in root-mean-square (RMS).
Results: With regard to the position of implant apex, the RMS distance of T1 from the control was 0.84mm. The RMS of T2, T3 and T4 were 0.28mm, 0.95mm and 0.29mm respectively.
Conclusions: Optical scanning of the model may be a radiation–free alternative to register implant position. Further studies are needed with sufficient sample size.