Graphic Processing Units (GPUs)-Based Haptic Simulator for Dental Implant Surgery

This paper presents a haptics-based training simulator for dental implant surgery. Most of the previously developed dental simulators are targeted for exploring and drilling purpose only. The penalty-based contact force models with spherical-shaped dental tools are often adopted for simplicity and computational efficiency. In contrast, our simulator is equipped with a more precise force model adapted from the Voxmap-PointShell (VPS) method to capture the essential features of the drilling procedure, with no limitations on drill shape. In addition, a real-time torque model is proposed to simulate the torque resistance in the implant insertion procedure, based on patient-specific tissue properties and implant geometry. To achieve better anatomical accuracy, our oral model is reconstructed from cone beam computed tomography (CBCT) images with a voxel-based method. To enhance the real-time response, the parallel computing power of GPUs is exploited through extra efforts in data structure design, algorithms parallelization, and graphic memory utilization. Results show that the developed system can produce appropriate force feedback at different tissue layers during pilot drilling and can create proper resistance torque responses during implant insertion

FIBER REINFORCED COMPOSITE AND METHODS OF FORMING THE SAME

EP1590150B1Granted Paten

A Study of Success Rate of Miniscrew Implants as Temporary Anchorage Devices in Singapore

Objective. To find out the success rate of miniscrew implants in the National Dental Centre of Singapore (NDCS) and the impact of patient-related, location-related, and miniscrew implant-related factors. Materials and Methods. Two hundred and eighty-five orthodontic miniscrew implants were examined from NDCS patient records. Eleven variables were analysed to see if there is any association with success. Outcome was measured twice, immediately after surgery prior to orthodontic loading (T1) and 12 months after surgery (T2). The outcome at T2 was assessed 12 months after the miniscrew’s insertion date or after its use as a temporary anchorage device has ceased. Results. Overall success rate was 94.7% at T1 and 83.3% at T2. Multivariate analysis revealed only the length of miniscrew implant to be significantly associated with success at both T1 (P=0.002) and T2 (P=0.030). Miniscrew implants with lengths of 10–12 mm had the highest success rate (98.0%) compared to other lengths, and this is statistically significant (P=0.035). At T2, lengths of 10–12 mm had significantly (P=0.013) higher success rates (93.5%) compared to 6-7 mm (76.7%) and 8 mm (82.1%) miniscrew implants. Conclusion. Multivariate statistical analyses of 11 variables demonstrate that length of miniscrew implant is significant in determining success

A Study of Success Rate of Miniscrew Implants as Temporary Anchorage Devices in Singapore

Objective. To find out the success rate of miniscrew implants in the National Dental Centre of Singapore (NDCS) and the impact of patient-related, location-related, and miniscrew implant-related factors. Materials and Methods. Two hundred and eighty-five orthodontic miniscrew implants were examined from NDCS patient records. Eleven variables were analysed to see if there is any association with success. Outcome was measured twice, immediately after surgery prior to orthodontic loading (T1) and 12 months after surgery (T2). The outcome at T2 was assessed 12 months after the miniscrew's insertion date or after its use as a temporary anchorage device has ceased. Results. Overall success rate was 94.7% at T1 and 83.3% at T2. Multivariate analysis revealed only the length of miniscrew implant to be significantly associated with success at both T1 ( = 0.002) and T2 ( = 0.030). Miniscrew implants with lengths of 10-12 mm had the highest success rate (98.0%) compared to other lengths, and this is statistically significant ( = 0.035). At T2, lengths of 10-12 mm had significantly ( = 0.013) higher success rates (93.5%) compared to 6-7 mm (76.7%) and 8 mm (82.1%) miniscrew implants. Conclusion. Multivariate statistical analyses of 11 variables demonstrate that length of miniscrew implant is significant in determining success

Early palatal shape change in infants with complete unilateral cleft lip and palate

Ph.DDOCTOR OF PHILOSOPH

3D printed twin block: A feasibility study

Aims: Twin blocks are appliances used for Class II skeletal discrepancies, where the lower jaw is positioned more posteriorly compared to the upper. The conventional method of fabrication of this appliance is tedious and labour-intensive; hence this study intends to explore the feasibility of a digital workflow to three-dimensionally (3D) print them. Methods: Three sets of twin blocks, identical except for amount of offset (0.0 mm, 0.1 mm and 0.2 mm), were designed and 3D printed for 5 anonymized scans of patients with Class II skeletal discrepancies. The intaglio surfaces of the 0.0 mm offset twin blocks were scanned and superimposed onto their original computer-aided-design files. The resultant colour maps, root mean square (RMS) deviations, and percentage in-tolerance values at thresholds of 0.1 mm and 0.2 mm were assessed. The fit and retention of all twin blocks were assessed on their 3D printed models via a fit and retention score (FRS). Results: The median RMS deviation was 0.10 mm; percentage in-tolerance values at thresholds of 0.1 mm and 0.2 mm were 79.90%, and 94.51%. Printing deviations occurred most often at labial and incisal edges anteriorly, and buccal and occlusal surfaces posteriorly. There was no significant difference between the total FRS for the three groups (p = 0.076). However, the frequency of satisfactory scores for upper fit (p = 0.049), lower fit (p = 0.018), upper retention (p = 0.038) and lower retention (p = 0.015) differed significantly between the three groups. Conclusion: This study demonstrated the viability of a digital workflow to 3D print twin blocks. Print accuracy was satisfactory, with 0.1 mm offset providing the best fit and retention

FIBER REINFORCED COMPOSITE AND METHODS OF FORMING THE SAME

WO2004058475A1Published Applicatio

Building confidence and competency in the delivery of local regional anaesthesia by undergraduate dental students with 3D printed anatomy models and augmented reality technology

Asian Journal of the Scholarship of Teaching and Learning9212-222Singapor