Color and translucency of milled polymethyl methacrylate crowns on non-tooth-colored interim abutments with different surface treatments.

STATEMENT OF PROBLEM: The interim rehabilitation of implants has become a necessity, particularly for those placed in the esthetic regions. However, the optical properties of computer-aided design and computer-aided manufacturing (CAD-CAM) polymethyl methacrylate (PMMA) crowns on interim abutments with different surface treatments are unclear. PURPOSE: The purpose of this in vitro study was to investigate the color and translucency of CAD-CAM PMMA crowns when different surface treatments were used on titanium interim abutments. MATERIAL AND METHODS: A maxillary dentate stone cast with a narrow-diameter implant analog at the left lateral incisor site was used. Three titanium interim abutments (blue) were divided into 3 groups according to the surface treatment they received: control (steam cleaning), opaqued (120-µm Al2O3 airborne-particle abrasion and opaque application), and airborne-particle abraded (120-µm Al2O3). Thirty PMMA crowns (A2 shade) were milled (n=10). The color coordinates of the crown-interim abutment pairs and a shade tab (A2) were measured by using a colorimeter. The color differences (ΔE00) between the crowns and the shade tab and the relative translucency parameter (RTP) values of the crowns were calculated by using the CIEDE2000 formula. One-way ANOVA was used to analyze the ΔE00 and RTP values with subsequent Tukey honestly significant difference tests (α=.05). RESULTS: The abutment surface treatment significantly affected the ΔE00 of interim crowns from the shade tab (P<.001), but no significant effect was found on RTP (P=.26). The control group had the highest ΔE00 from the shade tab (P≤.011). No significant difference (P=.14) was found between the opaqued and the ΔE00 of the airborne-particle abraded groups from the shade tab. CONCLUSIONS: The surface treatments of interim abutments affected the color of CAD-CAM PMMA crowns, which differed from that of the shade tab. The color of crowns on opaqued or airborne-particle abraded interim abutments was closer to the color of the shade tab. Abutment surface treatments did not affect the translucency of crown-interim abutment pairs.

Effect of Scanner Type and Scan Body Location on the Accuracy of Mandibular Complete-Arch Digital Implant Scans: An In Vitro Study.

PURPOSE: To compare the accuracy (trueness and precision) of scans of a newly introduced intraoral scanner (IOS) (Virtuo Vivo) and a widely used IOS (Trios 3) to a laboratory scanner (LBS) (Cares 7 SERIES) for 6 implants placed in an edentulous mandible, and to investigate the effect of scan body location on trueness. MATERIAL AND METHODS: Scanbodies were tightened on 6 implants placed in an edentulous polymethylmethacrylate mandibular model. An industrial scanner was utilized to generate a master reference model STL file. Three different scanners were used to scan the model (2 IOSs and 1 LBS), and the scans (n = 10) were exported into STL files. Best-fitting algorithm was used to superimpose test scans over the MRM-STL (nominal). ANOVA and Tukey HSD tests were performed to analyze the data (α = 0.05). RESULTS: The distance deviations in Car7-LBS scans were the highest (p < 0.001), whereas those in Tri-IOS scans were the lowest (p < 0.001). Vir-IOS had lower angular deviations than those of Tri-IOS (p = 0.031). In Vir-IOS scans, SB5 had higher distance deviations than SB2 (p = 0.029) and SB3 (p = 0.044). In Car7-LBS scans, SB1 had higher distance deviations than SB3 (p = 0.015) and SB5 (p = 0.005). In Tri-IOS scans, SB1 had higher mean distance deviations than SB2 and SB5 (p = 0.005). Vir-IOS had lower precision than Car7-LBS (distance deviation data) (p = 0.01). No difference was found among scanners for the precision of angular deviation data (p = 0.840). CONCLUSION: When trueness and precision were considered, distance and angular deviations depended on the scanner type. None of the scanners outperformed others in accuracy considering all distance and angular deviations. Scan body location affected only the trueness (distance deviations).

Delphi Project on the trends in Implant Dentistry in the COVID-19 era: Perspectives from Latin America.

AIM: To establish trends in Implant Dentistry in Latin America in the COVID-19 pandemic. MATERIAL AND METHODS: A steering committee and an advisory group of experts in Implant Dentistry were selected among eighteen countries. An open-ended questionnaire by Delphi methodology was validated including 64 questions, divided in 7 topics, concerning the various trends in dental implantology. The survey was conducted in two rounds, which provided the participants in the second round with the results of the first. The questionnaires were completed on August 2020, and the online meeting conference was held on September 2020. The final prediction was developed through consensus by a selected group of experts. RESULTS: A total of 197 experts from Latin America answered the first and second questionnaire. In the first round, the established threshold for consensus (65%) was achieved in 30 questions (46.87%). In the second round, performed on average 45 days later, this level was achieved in 47 questions (73.43%). Consensus was completely reached on the item "Diagnostic" (100%), the field with the lowest consensus was "Demand for treatment with dental implants" (37.5%). CONCLUSIONS: The present study in Latin America has provided relevant and useful information on the predictions in the education and practice of Implant Dentistry in the COVID-19 era. The consensus points toward a great confidence of clinicians in the biosecurity protocols used to minimize the risk of SARS-CoV-2 transmission. It is foreseen as an important change in education, with introduction of virtual reality and other simulation technologies in implant training.

Group 3 ITI Consensus Report: Patient-reported outcome measures associated with implant dentistry.

OBJECTIVES: The aim of Working Group 3 was to focus on three topics that were assessed using patient-reported outcome measures (PROMs). These topics included the following: (a) the aesthetics of tooth and implant-supported fixed dental prostheses focusing on partially edentulous patients, (b) a comparison of fixed and removable implant-retained prostheses for edentulous populations, and (c) immediate versus early/conventional loading of immediately placed implants in partially edentate patients. PROMs include ratings of satisfaction and oral health-related quality of life (QHRQoL), as well as other indicators, that is, pain, general health-related quality of life (e.g., SF-36). MATERIALS AND METHODS: The Consensus Conference Group 3 participants discussed the findings of the three systematic review manuscripts. Following comprehensive discussions, participants developed consensus statements and recommendations that were then discussed in larger plenary sessions. Following this, any necessary modifications were made and approved. RESULTS: Patients were very satisfied with the aesthetics of implant-supported fixed dental prostheses and the surrounding mucosa. Implant neck design, restorative material, or use of a provisional restoration did not influence patients' ratings. Edentulous patients highly rate both removable and fixed implant-supported prostheses. However, they rate their ability to maintain their oral hygiene significantly higher with the removable prosthesis. Both immediate provisionalization and conventional loading receive positive patient-reported outcomes. CONCLUSIONS: Patient-reported outcome measures should be gathered in every clinical study in which the outcomes of oral rehabilitation with dental implants are investigated. PROMs, such as patients' satisfaction and QHRQoL, should supplement other clinical parameters in our clinical definition of success.