Workflow for complete dentures fabrication in three appointments: A dental technique.

This technical report describes a novel workflow for complete denture fabrication designed to abbreviate the necessary steps for dental prostheses delivery by using a 3-appointment protocol in which preliminary impressions are made in the first session together with the registration of maxillary lip support, occlusal plane, and reference lines for tooth arrangement. A trial denture is fabricated with conventional or computer-aided design and computer-aided manufacturing procedures and is evaluated in the second appointment for esthetics, the definitive impression, and the maxillomandibular relationship record to provide precise references for definitive denture fabrication.

Physical, Mechanical, and Anti-Biofilm Formation Properties of CAD-CAM Milled or 3D Printed Denture Base Resins: In Vitro Analysis.

PURPOSE: To investigate surface characteristics (roughness and contact angle), anti-biofilm formation, and mechanical properties (mini-flexural strength) of computer-aided design and computer-aided manufacturing (CAD-CAM) polymethylmethacrylate (PMMA) polymer, and three-dimensional (3D) printed resin for denture base fabrication compared with conventional heat polymerized denture base resins. MATERIALS AND METHODS: A total of 60 discs and 40 rectangular specimens were fabricated from one CAD-CAM (AvaDent), one 3D printed (Cosmos Denture), and two conventional heat polymerized (Lucitone 199 and VipiWave) materials for denture base fabrication. Roughness was determined by Ra value; the contact angle was measured by the sessile drop method. The biofilm formation inhibition behavior was analyzed through Candida albicans adhesion, while mini-flexural strength test was done using a three-point bending test. The data were analyzed using descriptive and analytical statistics (α = 0.05). RESULTS: The CAD-CAM PMMA group showed the lowest C. albicans adhesion (log CFU/mL: 3.74 ± 0.57) and highest mini-flexural strength mean (114.96 ± 16.23 MPa). 3D printed specimens presented the highest surface roughness (Ra: 0.317 ± 0.151 µm) and lowest mini-flexural strength values (57.23 ± 9.07 MPa). However, there was no statistical difference between CAD-CAM PMMA and conventional groups for roughness, contact angle, and mini-flexural strength. CONCLUSIONS: CAD-CAM milled materials present surface and mechanical properties similar to conventional resins and show improved behavior in preventing C. albicans adhesion. Nevertheless, 3D printed resins present decreased mini-flexural strength.

Influences of build angle on the accuracy, printing time, and material consumption of additively manufactured surgical templates.

STATEMENT OF PROBLEM: Although desktop stereolithography (SLA) 3D printers and photopolymerizing resin have been used increasingly in dentistry to manufacture surgical templates, studies investigating their clinical application are lacking. PURPOSE: The purpose of this in vitro study was to evaluate the effects of build angle on the accuracy, printing time, and material consumption of additively manufactured surgical templates made with a desktop SLA 3D printer and photopolymerizing resin material. MATERIAL AND METHODS: Fifty surgical templates were fabricated from 1 master digital design file using a desktop SLA 3D printer and photopolymerizing resin material at 5 different build angles (0, 30, 45, 60, and 90 degrees) (n=10). All surgical templates were digitized and superimposed with the master design file using best-fit alignment in the surface matching software program. Dimensional differences between the sample files and the original master design files were compared, and the mean deviations were measured in the root mean square (measured in mm, representing accuracy). The printing time and resin consumption for each specimen were recorded based on the information in the 3D printing preparation software program. ANOVA and the Fisher least significant difference (LSD) test were used to estimate the effects of build angles on the root mean square, printing time, and resin consumption (α=.05 for all tests). RESULTS: The groups 0 degree (0.048 ±0.007 mm) and 45 degrees (0.053 ±0.012 mm) had statistically significant lower root mean square values when compared with those of groups 30 degrees (0.067 ±0.009 mm), 60 degrees (0.079 ±0.016 mm), and 90 degrees (0.097 ±0.017 mm) (P<.001 for all comparisons, except P=.003 for groups 30 degrees versus 45 degrees). The group 90 degrees had statistically significant higher root mean square values than all other groups (P<.001 for all comparisons, except P=.010 when compared with the group 60 degrees). For the printing time, the group 0 degree required significantly less printing time than all other groups (hour:minute, 1:26 ±0:03, P<.001 for all comparisons). The group 90 degrees required significantly more printing time than all other groups (2:52 ±0:06, P<.001 for all comparisons). For resin consumption, the groups 0 degree (11.58 ±0.21 mL), 30 degrees (11.32 ±0.16 mL), and 45 degrees (11.23 ±0.16 mL) consumed similar amounts of resin. However, there was statistical significance between groups 0 degree and 45 degrees (P=.016). The group 90 degrees consumed the significantly least amount of resin (9.86 ±0.40 mL, P<.001 for all comparisons). CONCLUSIONS: With a desktop SLA 3D printer, the 0-degree and 45-degree build angles produced the most accurate surgical template, and the 90-degree build angle produced the least accurate surgical template. The 0-degree build angle required the shortest printing time but consumed the most resin in the printing process. The 90-degree build angle required the longest printing time but consumed the least amount of resin in the printing process.