The use of additive manufacturing in dentistry has exponentially increased with dental model construction being the most common use of the technology. Henceforth, identifying the accuracy of additively manufactured dental models is critical. The objective of this study was to systematically review the literature and evaluate the accuracy of full-arch dental models manufactured using different 3D printing technologies. Seven databases were searched, and 2209 articles initially identified of which twenty-eight studies fulfilling the inclusion criteria were analysed. A meta-analysis was not possible due to unclear reporting and heterogeneity of studies. Stereolithography (SLA) was the most investigated technology, followed by digital light processing (DLP). Accuracy of 3D printed models varied widely between 500 μm with the majority of models deemed of clinically acceptable accuracy. The smallest (3.3 μm) and largest (579 μm) mean errors were produced by SLA printers. For DLP, majority of investigated printers (n = 6/8) produced models with <100 μm accuracy. Manufacturing parameters, including layer thickness, base design, postprocessing and storage, significantly influenced the model’s accuracy. Majority of studies supported the use of 3D printed dental models. Nonetheless, models deemed clinically acceptable for orthodontic purposes may not necessarily be acceptable for the prosthodontic workflow or applications requiring high accuracy.

To assess FRC FPDs longevity through systematically reviewing contemporary clinical evidence. Population investigated comprised patients requiring replacement of a single missing anterior/posterior tooth. Intervention was FRC FPDs. No control/comparison selected. Outcome was longevity of FRC FPDs. The focus question was: 'What is the longevity of FRC FPDs used to replace one anterior or posterior tooth in patients?' Randomised, non-randomised, controlled, prospective and retrospective clinical studies were included. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses were applied. The Overall Strength of Clinical Recommendation (OSCR) was assessed using the Strength of Recommendation Taxonomy system. Survival of FPDs was assessed using the Kaplan-Meier method. Analysis of FPD-survival according to location and occurrence of different failures was performed using Logrank and Chi-square testing. PubMed, MEDLINE, and Web of Science databases were searched between January 2007 and December 2015. Nine studies were included, involving placement of 592 FRC FPDs in 463 patients. Follow-up periods ranged between 2 months and 8 years. Kaplan-Meier overall survival probability was 94.5% (95%C.I: 92.5%-96.5%) at 4.8 years. There was no significant difference in survival probability of anterior versus posterior FRC FPDs (P=0.278). Veneering material fracture/delamination occurred significantly more than other types of failures (Ps<0.05). A meta-analysis could not be performed. OSCR was moderate. FRC FPDs demonstrated high overall survival with predictable performance outcomes. However, long-term performance remains unclear. FRC FPDs are viable medium-term management alternatives for replacing single anterior or posterior teeth in patients.

This paper reviews the current state of computer-aided design and manufacturing (CAD/CAM) in dentistry, with a special focus on restorative dental applications. The potential, advantages, and limitations of the technology will be discussed, comparing the digital workflow to conventional techniques, based on contemporary clinical evidence. The technology does seem to offer a more streamlined and efficient means of treatment planning and delivery of care through reduced chairside time, with reported improved patient satisfaction. Nonetheless, the accuracy and treatment outcomes of CAD/CAM treatment modalities are inconsistent and do not support a superior performance to existing conventional techniques, rather a comparable one.

Khaled E. Ahmed, BDS, MSc, PhD/John Whitters, BSc, PhD/Xiangyang Ju, BEng, MEng, PhD/S. Gareth Pierce, BSc, PhD/Charles N. MacLeod, MEng, PhD/Colin A. Murray, PhD, BDS: Purpose: The aim of this study was to clinically monitor the progression of tooth wear over a period of 1 year in a cohort of referred tooth wear patients through the use of a computer-aided design/ computer-assisted manufacture (CAD/CAM) scanner and a standardized scanning/assessment methodology. Materials and Methods: Polyether impressions were made of 11 participants (130 teeth) at baseline and at 1 year. Impressions were poured in type IV dental stone and the anterior teeth were 3D scanned. A surface-matching software was used to compare 1-year and baseline scans and identify any dimensional differences. Results: Parafunctional habits were reported by all patients. All participants exhibited tooth wear ≥ 140 μm in depth and extending to ≥ 280 μm in at least one tooth. Maxillary central incisors were the most commonly and severely affected teeth. Conclusion: The ability of the developed CAD/CAM scanning methodology in clinical monitoring of tooth wear was demonstrated. Further research is needed to assess its practicality in large-scale epidemiologic tooth wear studies.