Kuan Yee Wong1,2, Roxanna Jean Esguerra3, Vanessa Ai Ping Chia4, Ying Han Tan5, Keson Beng Choon Tan6. 1. Department of Dental Surgery, Khoo Teck Puat Hospital, Singapore, Republic of Singapore. 2. Former resident in Postgraduate Prosthodontics, Faculty of Dentistry, National University of Singapore, Singapore, Republic of Singapore. 3. Private Practice, Denver, CO. 4. Department of Restorative Dentistry, National Dental Centre, Singapore, Republic of Singapore. 5. Private Practice, Singapore, Republic of Singapore. 6. Faculty of Dentistry, National University of Singapore, Singapore, Republic of Singapore.
Abstract
PURPOSE: Prior studies have defined the accuracy of intraoral scanner (IOS) systems but the accuracy of the digital static interocclusal registration function of these systems has not been reported. This study compared the three-dimensional (3D) accuracy of the digital static interocclusal registration of 3 IOS systems using the buccal bite scan function. MATERIALS AND METHODS: Three IOS systems compared were 3MTM True Definition Scanner (TDS), TRIOS Color (TRC), and CEREC AC with CEREC Omnicam (CER). Using each scanner, 7 scans (n = 7) of the mounted and articulated SLA master models were obtained. The measurement targets (SiN reference spheres and implant abutment analogs) were in the opposing models at the right (R), central (C), and left (L) regions; abutments #26 and #36, respectively. A coordinate measuring machine with metrology software compared the physical and virtual targets to derive the global 3D linear distortion between the centroids of the respective target reference spheres and abutment analogs (dRR , dRC , dRL , and dRM ) and 2D distances between the pierce points of the abutment analogs (dXM , dYM , dZM ), with 3 measurement repetitions for each scan. RESULTS: Mean 3D distortion ranged from -471.9 to 31.7 μm for dRR , -579.0 to -87.0 μm for dRC , -381.5 to 69.4 μm for dRL , and -184.9 to -23.1 μm for dRM . Mean 2D distortion ranged from -225.9 to 0.8 μm for dXM , -130.6 to -126.1 μm for dYM , and -34.3 to 26.3 μm for dZM . Significant differences were found for interarch distortions across the three systems. For dRR and dRL , all three test groups were significantly different, whereas for dRC , the TDS was significantly different from the TRC and CER. For 2D distortion, significant differences were found for dXM only. CONCLUSIONS: Interarch and global interocclusal distortions for the three IOS systems were significantly different. TRC performed overall the best and TDS was the worst. The interarch (dRR , dRC , dRL ) and interocclusal (dXM ) distortions observed will affect the magnitude of occlusal contacts of restorations clinically. The final restoration may be either hyperoccluded or infraoccluded, requiring compensations during the CAD design stage or clinical adjustments at issue.
PURPOSE: Prior studies have defined the accuracy of intraoral scanner (IOS) systems but the accuracy of the digital static interocclusal registration function of these systems has not been reported. This study compared the three-dimensional (3D) accuracy of the digital static interocclusal registration of 3 IOS systems using the buccal bite scan function. MATERIALS AND METHODS: Three IOS systems compared were 3MTM True Definition Scanner (TDS), TRIOS Color (TRC), and CEREC AC with CEREC Omnicam (CER). Using each scanner, 7 scans (n = 7) of the mounted and articulated SLA master models were obtained. The measurement targets (SiN reference spheres and implant abutment analogs) were in the opposing models at the right (R), central (C), and left (L) regions; abutments #26 and #36, respectively. A coordinate measuring machine with metrology software compared the physical and virtual targets to derive the global 3D linear distortion between the centroids of the respective target reference spheres and abutment analogs (dRR , dRC , dRL , and dRM ) and 2D distances between the pierce points of the abutment analogs (dXM , dYM , dZM ), with 3 measurement repetitions for each scan. RESULTS: Mean 3D distortion ranged from -471.9 to 31.7 μm for dRR , -579.0 to -87.0 μm for dRC , -381.5 to 69.4 μm for dRL , and -184.9 to -23.1 μm for dRM . Mean 2D distortion ranged from -225.9 to 0.8 μm for dXM , -130.6 to -126.1 μm for dYM , and -34.3 to 26.3 μm for dZM . Significant differences were found for interarch distortions across the three systems. For dRR and dRL , all three test groups were significantly different, whereas for dRC , the TDS was significantly different from the TRC and CER. For 2D distortion, significant differences were found for dXM only. CONCLUSIONS: Interarch and global interocclusal distortions for the three IOS systems were significantly different. TRC performed overall the best and TDS was the worst. The interarch (dRR , dRC , dRL ) and interocclusal (dXM ) distortions observed will affect the magnitude of occlusal contacts of restorations clinically. The final restoration may be either hyperoccluded or infraoccluded, requiring compensations during the CAD design stage or clinical adjustments at issue.
Authors: Keyan P Botsford; Michael C Frazier; Ahmed A M Ghoneima; Achint Utreja; Surya S Bhamidipalli; Kelton T Stewart Journal: Angle Orthod Date: 2019-03-28 Impact factor: 2.079