Conventional and digital maxillary occlusal record for the manufacture of complete-arch implant-supported fixed prostheses: randomized controlled clinical trial.

OBJECTIVES: To evaluate the trueness of the digital maxillary occlusal records in comparison with the conventional records for the fabrication of complete-arch implant-supported fixed prostheses. MATERIALS AND METHODS: This randomized controlled clinical trial followed the recommendations of the CONSORT statement. Twenty participants who used a mandibular interim complete-arch fixed prosthesis and conventional complete maxillary dentures were included in the study. The participants were randomized into two types of maxillary occlusal records: conventional (COR) and digital (DOR) (TRIOS; Shape A/S). After fabricating the prostheses, the distribution and number of occlusal contact points, and the time taken to obtain the maxillary occlusal record and work model were evaluated. Descriptive analysis was used to evaluate the distribution of occlusal contact points. The Wilcoxon test was employed for assessing the number of occlusal contact points, while the Mann-Whitney U test was used for the time taken to obtain the working casts and the maxillary occlusal record and occlusal adjustment times (p < 0.05). RESULTS: There was a similarity in the jaw relation recording methods regarding the distribution of occlusal contact points. There was no difference in the number of occlusal contact points between the anterior (p = 0.439) and posterior (p = 0.227) teeth. No relationship was observed between the distribution and number of occlusal contact points (COR, p = 0.288; DOR, p = 0.183). DOR required less occlusal and clinical adjustment time, on the other hand more laboratory and total workflow time than COR (p < 0.001). CONCLUSION: The DOR may be an option for obtaining the functional space necessary for the assembly of teeth in complete-arch implant-supported fixed prostheses; however, it requires more working time. CLINICAL RELEVANCE: The digital occlusal recording method can be used to assess the interocclusal space for the virtual tooth setup of a complete-arch implant-supported fixed prosthesis.

Complications and Patient-Centered Outcomes of an Implant- Supported Single Crown after Immediate and Delayed Loading: A Systematic Review and Meta-analysis.

Single implants are a predictable treatment, and immediate loading can be an option with acceptable survival rates. Clinical and patient-centered outcomes comparing immediate and delayed protocol of single implants are unclear. The purpose of this study was to assess complications, satisfaction, and quality of life of patients rehabilitated with delayed and immediate loading single crowns. An electronic search was conducted in PubMed/MEDLINE, Scopus, Web of Science, Cochrane Library, and Embase databases up to February 2023. Only prospective studies, randomized and non-randomized clinical trials comparing immediate and delayed loading were included. For the quantitative analysis, dichotomous and continuous variables were evaluated with a 95% confidence interval. A total of 20 studies were evaluated. No statistically significant difference between protocols was observed: satisfaction (I2: 0%; P = 0.42), quality of life (I2: 0 %; P = 0.05), biological complications (I2: 9%; P = 0.17) mechanical complications (I2: 58%; P = 0.84), and survival rate (I2: 0%; P = 0.38). Subgroup analysis showed significant differences only for marginal bone loss when immediate implants were placed in the mandible (IÇ: 15%; P = 0.01) and posterior zone (I2: 0%; P = 0.001). Complications and patient-centered outcomes for immediate single-implant crowns were comparable to delayed loading. Scientific evidence showed no significant difference between loading protocols for survival rates. Although several factors could interfere with the complication events, implant failures, and marginal bone loss, the subgroup analysis evidenced that only immediate implants placed in the posterior mandible zone had higher statistically significant mean marginal bone loss.

Targeting bonding protocols to increase the bond between acrylic resin or 3D printed denture bases and prefabricated or 3D printed denture teeth.

STATEMENT OF PROBLEM: The difference in chemical composition between denture base resin and denture teeth requires the development of bonding protocols that increase the union between the materials. PURPOSE: The purpose of this in vitro study was to evaluate the impact of different bonding protocols on the bond between heat-polymerized and 3-dimensionally (3D) printed acrylic resin denture bases and acrylic resin prefabricated and 3D printed artificial teeth. MATERIAL AND METHODS: Four types of artificial teeth were evaluated: prefabricated acrylic resin (VITA MFT) and 3D printed (Cosmos TEMP, PRIZMA 3D Bio Denture, and PrintaX AA Temp) bonded to 20×24-mm cylinders of heat-polymerized (VipiWave) and 3D printed (Cosmos Denture, PRIZMA 3D Bio Denture, and PrintaX BB Base) denture bases. Three bonding protocols were tested (n=20): mechanical retention with perforation + monomer (PT1), mechanical retention with perforation + airborne-particle abrasion with 50-µm aluminum oxide + monomer (PT2), and mechanical retention with perforation + Palabond (PT3). Half of the specimens in each group received 10 000 thermocycles and were then subjected to the bonding test at a crosshead speed of 1 mm/minute. The failure type was analyzed and scanning electron micrographs made. Additionally, surface roughness (Ra) and wettability (degree) were analyzed (n=15). ANOVA was used to evaluate the effect of the bonding protocol, and the Student t test was applied to compare the experimental groups with the control (α=.05). For type of failure, a descriptive analysis was carried out using absolute and relative frequency. The Kruskal-Wallis test was used to evaluate the surface changes (α=.05). RESULTS: Among the protocols, PT3 with in Yller and PT2 with Prizma had the highest bond strengths of the heat-polymerized denture base and 3D printed teeth (P<.05). When comparing the experimental groups with the control, PT3 and PT2 had greater union with the 3D printed denture base + 3D printed teeth (in Yller), with no difference from the heat-polymerized denture base + prefabricated teeth in acrylic resin. The treatment of the 3D printed tooth surfaces affected the surface roughness of Prizma (P<.001) and wettability (P<.001). CONCLUSIONS: To increase the bond between Yller 3D printed denture base + 3D printed teeth, a bonding protocol including mechanical retention with perforation + Palabond or mechanical retention with perforation + airborne-particle abrasion with aluminum oxide + monomer is indicated. For the other materials tested, further bonding protocols need to be investigated.

Impact of using magnifying dental loupes on clinical performance during tooth preparation: A systematic review.

Background: To assess whether using magnification loupes affects tooth preparation working posture performed by undergraduate students and dentistry professionals and whether it influences the quality of the preparation, operator satisfaction and procedure time. Material and Methods: This review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement and registered in the International Prospective Register of Systematic Review (CRD42023482377). Electronic searches were conducted in PubMed/Medline, Cochrane Library, Web of Science, and Scopus databases for relevant articles published up to August 2023. Clinical or laboratory studies evaluating cavities or dental preparations performed with and without magnification loupes were considered eligible. The outcomes were operator working posture, dental preparation quality, operator satisfaction, and procedure time. The quality of the studies was evaluated using the JBI Critical Appraisal tools for Quasi-Experimental Studies. Results: The searches retrieved 1493 articles. Based on the eligibility criteria, 11 laboratory studies were included, where 410 undergraduate and graduate dental students conducted dental preparations in 1851 dental specimens. Of the 11 selected studies, 6 evaluated the working posture, 6 assessed the quality of the dental preparations, 5 reported operator satisfaction, and 2 assessed procedure time. The results showed that magnifying loupes significantly improved operator working posture, but did not influence the quality of tooth preparations. Although satisfaction reports about experiences with magnifying loupes were favorable, no significant difference was found. Conclusions: Magnification loupes improved operator working posture. However, clinical studies with more scientific evidence are needed for steady conclusions regarding operator satisfaction and procedural time. Key words:Magnification, dental loupes, tooth preparation, cavity preparation, dental education.

Fabrication of digital complete dentures guided by facial scanning with a device for recording the maxillomandibular relation: A dental technique.

This article describes a technique for the fabrication of digital complete dentures guided by facial scanning using an innovative device for maxillomandibular relation records. For this, a device was designed and 3-dimensionally (3D) printed to assist in the maxillomandibular record stage. Digital files of the diagnostic casts, jaw relation record, and facial images were superimposed, and the complete denture was virtually planned. Subsequently, trial complete dentures were 3D printed, and a functional and esthetic clinical tooth evaluation was conducted. Then, definitive impressions were made, and definitive complete dentures were obtained. The method of recording the maxillomandibular relation associated with facial scanning in a digital workflow for manufacturing the dentures in a 3-appointment protocol provided better predictability of patient care and reduced clinical and laboratory time than with the conventional denture technique.

Complete denture rehabilitation for a patient with Parkinson's disease using clinical strategies: A case report.

OBJECTIVE: To present clinical strategies for prosthetic rehabilitation with complete dentures (CDs) of a Parkinson's disease patient. CASE REPORT: An 82-year-old patient sought the Department of Dentistry at UFRN, reporting retention dissatisfaction and hamper to the mandibular CD adaptation. Patient-reported a dry mouth sensation, and exhibited disordered mandibular movements, tremors, and resorbed mandibular ridge. Aiming retention and stability, double molding with zinc enolic oxide impression paste, neutral zone technique, and non-anatomic teeth were proposed as clinical strategies. At delivery, identification and relief in the supercompression areas were performed to facilitate the acceptance and use of the new dentures. CONCLUSION: The strategies promoted patient satisfaction regarding retention, stability, and comfort. This treatment may be considered for the rehabilitation of Parkinson's disease patients, favoring the adaptation process.

Factors Associated with Nonadaptation to New Mandibular Complete Dentures: A Scoping Review.

PURPOSE: To identify and map the scientific evidence regarding factors associated with the nonadaptation of completely edentulous patients to mandibular complete dentures. MATERIALS AND METHODS: This scoping review followed the PRISMA-ScR statement for Scoping Reviews and was based on guidelines proposed by Arksey and O'Malley and the Joanna Briggs Institute Manual for Evidence Synthesis. The methodology was registered on the Open Science Framework. An electronic search strategy was conducted in PubMed/MEDLINE, Web of Science, Scopus, Cochrane Library, Virtual Health Library, ClinicalTrials.gov, Google Scholar, and ProQuest databases was conducted. Studies that evaluated factors associated with adaptation to and acceptance of mandibular complete dentures were included, such as sociodemographic, psychologic, patient-related, and denture-related items. RESULTS: The search conducted in March 2022 yielded 9,978 studies. In total, 24 studies were included for data extraction. Sociodemographic factors did not interfere with adaptation to a mandibular complete denture. Psychologic factors and patient-related aspects showed greater association with nonadaptation to mandibular complete dentures than denture-reported factors. CONCLUSION: Although it is suggestive that psychologic and patient-related factors have higher association with the acceptance of new dentures, data must be interpreted with caution due to the variability of methodologies of the studies included in this review.

Impact of CAD/CAM Material and Bonding Protocol on the Bond Strength Between Denture Bases and Artificial Teeth: A Systematic Review and Meta-analysis

PURPOSE: To identify the most effective protocol for bonding denture bases and artificial teeth made with different computer-aided design and manufacturing (CAD/CAM) materials (milled and 3D-printed) and conventional heat-polymerized resins. MATERIALS AND METHODS: This review was performed according to the Preferred Reporting Items for Systematic and Meta-Analysis (PRISMA) criteria and registered in the International Prospective Registry of Systematic Reviews PROSPERO (CRD42021276084). An electronic search was performed independently by two examiners in PubMed/MEDLINE, Cochrane Library, Scopus, Web of Science, ProQuest, and OpenGrey databases for articles published up to and including December 2021. RESULTS: The electronic search returned 806 articles, and after duplicates were removed, 589 articles remained. Four articles met the eligibility criteria to be included in this study. After evaluating the different combinations of denture base materials and artificial teeth, it was found that IvoBase CAD Bond (Ivoclar Vivadent) was effective for bonding CAD/CAM denture bases to prefabricated acrylic resin teeth, which showed no differences compared to the heat-polymerized resin denture base bonded to prefabricated acrylic resin teeth (χ2: 68.56; I2: 96%; P < .001). CONCLUSIONS: The IvoBase CAD Bond bonding system can be used for the fabrication of CAD/CAM denture bases with prefabricated acrylic resin teeth.

Accuracy and reproducibility of real and virtual occlusal contact points in implant-supported fixed prostheses.

AIM: To evaluate the accuracy and reproducibility of real and virtual occlusal contact points in implant-supported, fixed complete dentures. MATERIALS AND METHODS: The study included 19 participants using mandibular interim complete-arch fixed prosthesis supported by 3 or 4 implants as opposed to conventional removable complete dentures. At installation, an examiner installed the prostheses and verified the occlusal contact points through 2 methods: recording the real contact points with carbon paper (RC) followed by occlusal photography and intraoral scanning (VC) to record the virtual contact points to obtain a screen print of the software. Then, the two images were randomized to determine the order to be inserted into Microsoft PowerPoint for blind and paired evaluation. The independent variables consisted of the distribution of occlusal contacts points (qualification through pre-defined scores based on the position of the contact points on the surfaces of the teeth) and the reproducibility of the methods by verifying the number of occlusal points. For this, a descriptive analysis was used to evaluate the distribution of occlusal contacts points and the Wilcoxon test for the reproducibility of the occlusal contact points between the methods (p<0.05). RESULTS: The methods had 100% and 73.6% real and virtual occlusal contact points, respectively, which is considered clinically excellent. There was no significant difference regarding the reproducibility of the methods by the number of occlusal contact points (RC: x̅13.32; VC: x̅13.68; p=0.715). CONCLUSION: The use of the tested intraoral scanner can be an easy and fast tool for studying and mapping the occlusion, and storing data for future treatment, with the conventional method being the preferred method for performing the occlusal adjustment.

Accuracy of models of partially edentulous arches obtained by three-dimensional printing: An in vitro study.

Aim: The aim of this study was to evaluate the accuracy of models of partially edentulous arches obtained by three-dimensional (3D) printing. Settings and Design: This was an in vitro study. Materials and Methods: Fifteen partially edentulous models were evaluated, using two methods of measuring dimensions: virtual, using the Standard Tessellation Language files of the models and software (control group), and physical, through printing the models and digital caliper (test group). For both methods, measurements were made regarding the dimensions of the teeth (width and length - buccal/lingual or palatal/occlusal) and distances between the teeth. Statistical Analysis Used: For the variable of linear measurements (width and length) and distances between teeth of the same hemiarch, the Wilcoxon test was used, while for the variable between opposite hemiarches, the paired t-test was used. Results: In the evaluation of the linear measurements, a significant difference was observed only when the width of the molar tooth was analyzed (P = 0.014). When the buccal length was measured, all teeth had linear measurements provided by the virtual method that was lower than the physical (P = 0.000), as well as the lingual/palatal length in incisors (P = 0.003) and molars (P = 0.009) and in total (P = 0.001). As for the analyses between teeth, no difference was identified between the measurements provided by the virtual method compared to the physical one. Conclusions: The 3D printer used to print partially edentulous models provided linear distortions in the teeth but without changes in the distances between teeth of the same hemiarch and between teeth of opposite hemiarches.

Use of impression technique to identify areas of super compression before installation of new complete dentures: a randomized double-blind trial.

OBJECTIVE: To identify pressure areas using an impression technique and to evaluate whether adjustment of dentures prior to installation can decrease ulcer frequency, number of adjustments, and improve satisfaction with treatment. MATERIALS AND METHODS: Fifty complete denture users were selected and randomly divided into two groups. Pressure areas were identified in 25 subjects using the impression technique with fluid silicone, and the denture base in these areas was adjusted before installation. A total of 25 subjects received new complete dentures without adjustments before installation. The number of ulcers observed was registered at 1, 7, 15, and 30 days after installation. Patient satisfaction was collected before and 1 month after the installation. The number of necessary post-installation adjustments was considered. Comparisons between the groups with respect to the number of ulcers, adjustments, and patient satisfaction were performed using the Mann-Whitney test. RESULTS: Identification of pressure areas reduced the number of ulcers after installation of the new prostheses. These results were observed in the 1- (p = 0.004) and 7-day (p = 0.002) adjustments for the maxilla and in all the adjustments for the mandible. The technique improved patient satisfaction (p = 0.031) and reduced the number of post-installation adjustments (p ≤ 0.001). CONCLUSION: A reduction in the incidence of ulcers, number of adjustments and improvement in patient satisfaction could be observed with the use of the technique.

Bond strength between denture lining material and CAD-CAM denture base resin: A systematic review and meta-analysis.

STATEMENT OF PROBLEM: An effective bond between a denture lining material and the denture base resin is necessary for proper function. Regarding the new technologies for manufacturing denture bases, a systematic search of the literature on this topic is lacking. PURPOSE: The purpose of this systematic review and meta-analysis was to evaluate the bond strength between denture lining material and computer-aided design and computer-aided manufacturing (CAD-CAM) denture base resin (milled and 3-dimensionally printed) versus conventional denture base resin. MATERIAL AND METHODS: Electronic databases (PubMed/MEDLINE, Scopus, and Web of Science) were independently searched by 4 researchers for relevant studies published up to April 2023. The population, intervention, comparison, and outcome (PICO) question was: "Comparing conventional and CAD-CAM (milled and 3-dimensionally printed) denture base materials, which promote greater bond strength when associated with denture lining material?" A meta-analysis was performed based on mean ±standard deviation bond strength values between denture base resins and denture lining material with 95% confidence intervals. RESULTS: Five in vitro studies were included. For bond strength, no difference was noted between conventional and milled denture base resin (confidence interval: -0.99 [-2.17 to 0.20]; heterogeneity: t2=0.57; Chi2:4.57; I2=78%; P=.10), and conventional resin had better values compared with those of 3-dimensionally (3D) printed (confidence interval: 3.03 [2.40-3.66]; heterogeneity: t2=0.00; Chi2:0.56; I2=0%; P<.001) when relined with soft materials. The milled denture base resin was better than the conventional (confidence interval: -0.85 [-1.33 to -0.38]; heterogeneity: Chi2:28.87; I2=93%; P<.001), with no difference between 3D printed and conventional (confidence interval: 0.18 [-4.23 to 4.59]; heterogeneity: t2=16.51; Chi2:130.99; I2=98%; P=.94) for hard liners. CONCLUSIONS: The bond strength between resins for milled CAD-CAM denture bases and denture lining material was similar to that of conventional denture base resin, regardless of the consistency of the denture lining material. The bond strength to 3D printed CAD-CAM resin was lower than that of the milled version.

Virtual facebow techniques: A scoping review.

STATEMENT OF PROBLEM: Although advances in technology continue to improve the acquisition of patient data and the manufacturing of different oral rehabilitations, the method of transferring clinical information to a virtual environment has not yet been consolidated in the literature. PURPOSE: The purpose of this scoping review was to map the existing literature on different techniques of transferring information from virtual facebows for oral rehabilitation. MATERIAL AND METHODS: This scoping review was structured using a 5-step methodology based on guidelines proposed by Arksey and O'Malley: (1) characterization of the research question, (2) identification of relevant studies, (3) selection of studies, (4) mapping of results, and (5) selection, summary and reporting of the data. The Joanna Briggs Manual for Evidence Synthesis was followed and the review was guided by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR). The guiding question for the development of this review was, "What virtual facebow techniques are being used to transfer anatomic data to the virtual environment?" RESULTS: A total of 1745 articles were found during the search, and 20 were included in this review. Nineteen of the included articles had positive results with the described techniques of registration and transfer of anatomic references to the virtual environment; however, 1 study indicated that the technique was negative. CONCLUSIONS: Based on the findings, facial scanning, 2-dimensional photographs, and cone beam computed tomography are feasible methods of acquiring extraoral anatomic landmarks. The use of a device that allows the convergence of intraoral and extraoral images by superimposing data was revealed to be a promising option.

Device trueness in passivity and misfit of CAD-CAM frameworks: Conventional versus printed casts.

STATEMENT OF PROBLEM: Obtaining a passive and well-adapted framework is challenging when intraoral scanning edentulous arches with multiple implants. The trueness of the printed casts is unclear. PURPOSE: The purpose of this clinical study was to evaluate the trueness of frameworks made from conventional and printed casts regarding clinical passivity and misfit. MATERIAL AND METHODS: Ten participants with complete mandibular fixed implant-supported interim prostheses retained by 4 implants were included. Each participant had a conventional impression and a digital scan made. The digital scan was made using an innovative device. Both conventional and digital casts were made, and the virtual images were used for milling the digital framework in cobalt chromium alloy. All frameworks were evaluated for passivity and marginal vertical misfit with the single screw test, with 4 attempts consisting of the tightened screw position, a test with all screws tightened, and an interspersed tightening test. The Kruskal-Wallis test was used to evaluate the trueness of the tested device for framework construction through the single screw test on vertical marginal misfit in the conventional and printed groups (α=.008). The Friedman test was used to assess the effect of test type (α=.05), and the Wilcoxon test was used to identify group-to-group differences (α=.017). RESULTS: The absence of space between the framework and the abutments and interferences during its placement, as well as good stability, were observed clinically. In laboratory analysis, greater framework misfits were observed in the printed group compared with the conventional group when the single screw test was applied. Comparing the 3 tests used, the greatest misfits were observed when the framework was screwed onto the printed cast. CONCLUSIONS: The innovative device tested for the intraoral scanning of multiple implants had clinically acceptable accuracy for the construction of passive and adapted frameworks. The conventional cast was more accurate than the printed cast, with lower misfit values, in all tests.

Nonadaptation to New Mandibular Complete Dentures: A Survival Analysis and Interpretation of the Time to Adaptation.

PURPOSE: To determine the average time for patients to adapt to mandibular complete dentures (CDs) and the factors associated with this critical period. MATERIALS AND METHODS: In total, 108 completely edentulous patients were rehabilitated using CDs. Adaptation was evaluated based on the following criteria: mastication, comfort, speech, and swallowing with dentures. The Kaplan-Meier method was used to estimate the average time to adaptation. The logrank test was used to assess the adaptation period and associated factors. RESULTS: Of the 108 rehabilitated patients, 89 had adapted to mandibular CDs at the 6-month follow-up. The mean time to adaptation estimated from the Kaplan-Meier curve was 78.54 days (95% confidence interval [CI] 71.04 to 86.04). The factors associated with the adaptation period were previous experience with a mandibular denture (P = .032), the professional who made the previous CDs (P = .034), frequency of appearance of traumatic lesions after 15 days of rehabilitation (P = .023), posterior mandibular ridge height (P = .005), and regular use of the new dentures (P = .002). CONCLUSIONS: Most patients adapted to mandibular dentures after 2.6 months. Lack of prior experience with mandibular dentures, use of old dentures made by a dental technician, occurrence of traumatic injuries 15 days after CD delivery, presence of a resorbed posterior mandibular ridge, and nonregular wear were associated with longer adaptation time to new mandibular CDs.

Effect of cantilever extension on bone loss in mandibular complete-arch implant-supported fixed prosthesis about 3 and 4 implants.

STATEMENT OF PROBLEM: The assessment of bone loss around implants has been widely studied, but the effect of cantilever length as a risk factor is not fully understood. PURPOSE: The objective of this randomized controlled clinical trial was to compare the peri-implant bone loss of mandibular complete-arch implant-supported fixed prosthesis supported (FPS) by 3 and 4 implants and to correlate with the size of the horizontal and vertical distal cantilever at prosthesis installation (T1) and after one year (T2). MATERIALS AND METHODS: 72 external hexagon (EH) type implants were installed in 20 participants. Of these, 24 support FPS with 3 implants (GI3) and 48 with 4 implants (GI4). The inferior implants were named 1, 2, 3, and 4 according to their location in the mandibular arch, in a clockwise direction. Digital periapical radiographs were taken at times T1 and T2 for analysis and measurement of peri-implant bone loss. The horizontal and vertical distal cantilevers were measured with a digital caliper and correlated with peri-implant bone loss. RESULTS: The survival rate of implants in GI3 was 91.66%, in GI4 it was 97.91%. The mean bone loss in GI3 was 0.88 (± 0.89) mm and in GI4 it was 0.58 (± 0.78) mm (P = 0.225). There was no correlation between distal horizontal cantilevers and bone loss in the studied groups, with GI3 being -0.25 (P=0.197) and GI4-0.22 (0.129). Larger vertical cantilevers of implants 1 (P=0.018), 3 (P=0.015) and 4 (P=0.045) correlated with greater bone loss in GI4. CONCLUSION: The number of implants in FPS did not influence peri-implant bone loss after 1 year of follow-up. Larger vertical cantilevers influenced greater bone loss in complete-arch implant-supported fixed prosthesis supported by 4 implants. Int J Prosthodont. 10.11607/ijp.8347.

Factors associated with the non-adaptation to new mandibular complete dentures: a scoping review.

PURPOSE: To identify and map the scientific evidence regarding the factors that may influence the adaptation of complete edentulous to the mandibular complete denture. MATERIALS AND METHODS: An electronic search strategy in the PubMed/MEDLINE, Web of Science, Scopus, Cochrane Library, and Virtual Health Library databases from 1945 to 2021, was conducted, according to the criteria established by PRISMA-ScR. Studies that addressed factors that influenced adaptation and acceptance to mandibular complete denture were included, such as socio-demographic and psychological aspects and patient-centered condition, and denturer-elated factors. RESULTS: The search yielded 9264 studies, of which 87 articles were considered eligible for full-text screening. Of this total, 23 were included for data extraction. Sociodemographic factors do not interfere with adaptation to a mandibular complete denture. Reports of complaints regarding pain and discomfort negatively impact the acceptance of complete dentures. Patients with a neuroticism personality have more difficulty accepting the complete dentures, being more predisposed to abandon them. CONCLUSION: The psychological condition interferes with the predictability of treatment. Older and female patients, using first mandibular dentures, with resorbed ridges, and poor technical quality had more difficulty adapting to the complete dentures. However, these data must be interpreted with caution due to the variability of methodologies of the studies included in this review. Int J Prosthodont 2023. doi: 10.11607/ijp.7774.

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.

Accuracy between intraoral and extraoral scanning: Three-dimensional deviation and effect of distance between implants from two scanning methods.

Aim: Evaluate the accuracy between the intraoral and extraoral scanning regarding the three dimensional (3D) deviation and distances between the implants, through 2 scanning methods. Settings and Design: An in vitro study. Materials and Methods: An edentulous mandibular model was used to install four implants and abutments, recommending 6 distances between the implants. Scans were performed using an intraoral (SI) and extraoral (SE) scanner for each studied group: Scanning with the scan bodies (SB) and device (SD) (n = 10). The files were imported into a surface evaluation program to assess 3D deviations and measure distances between implants. Statistical Analysis: Precision was assessed as the difference between files (Kruskal-Wallis test), while trueness was assessed from the difference between scans, applying the Wilcoxon and Mann-Whitney test. Results: As for the 3D deviations, SI showed accuracy, for the faces and positions of the implants in relation to the SE, in both scanning methods (P < 0.05). Regarding the capture of distances between implants, the SD scan obtained better trueness than the SB group (P < 0.05). Conclusion: We concluded that the type and scanning methods used did not influence the 3D deviations, while for distances, scanning with the device had better trueness.

Conventional and digital impressions for complete-arch implant-supported fixed prostheses: time, implant quantity effect and patient satisfaction.

PURPOSE: To evaluate and compare the effect of impression type (conventional vs digital) and the number of implants on the time from the impressions to the generation of working casts of mandibular implant-supported fixed complete-arch frameworks, as well as on patient satisfaction. MATERIALS AND METHODS: 17 participants, 3 or 4 implants, received 2 types of digital impression methods (DI) and conventional (CI). In DI, two techniques were performed: scanning with the scan bodies (SC) and scanning with a device attached to the scan bodies (SD) (BR 10 2019 026265 6). In CI, the making of a solid index (SI) and open-tray impression (OT) were used. The outcomes were used to evaluate the time and the participant satisfaction with conventional and digital impressions. The time was evaluated through the timing of the time obtained in the workflow in the conventional and digital impression. The effect of the number of implants on time was also assessed. Satisfaction was assessed through a questionnaire based on seven. The Wilcoxon test used to identify the statistical difference between the groups in terms of time. The Mann-Whitney test was used to analyze the relationship between the time and the number of implants. Fisher's test was used to assess the patient satisfaction (P < .05). RESULTS: The time with DI was shorter than with CI (DI, x̃=02:58; CI, x̃=31:48) (P < .0001). The arches rehabilitated with 3 implants required shorter digital impression time (3: x̃=05:36; 4: x̃=09:16) (P < .0001). Regarding satisfaction, the DI was more comfortable and pain-free than the CI (P < .005). CONCLUSION: Digital impressions required shorter chair time and had higher patient acceptance than conventional impressions.