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BMC Oral Health Feb 2024The aim of this study was to describe a novel digital technique to analyze the wear of screw-retained implant-supported metal-ceramic dental prostheses and natural tooth...
The aim of this study was to describe a novel digital technique to analyze the wear of screw-retained implant-supported metal-ceramic dental prostheses and natural tooth as antagonist.Materials and methods Ten patients were consecutively included to rehabilitate partial edentulism by dental implants. Both the screw-retained implant-supported metal-ceramic dental prostheses and the natural tooth as antagonist were submitted to a digital impression through an intraoral scan to generate a Standard Tessellation Language digital file preoperatively (STL1), at 3 months (STL2), and 6 months (STL3) follow-up. Afterwards, an alignment procedure of the digital files (STL1-STL3) was performed on a reverse engineering morphometric software (3D Geomagic Capture Wrap) and volume changes at the screw-retained implant-supported metal-ceramic dental prostheses and the natural tooth as antagonist were analyzed using Student's t-test. Moreover, Gage R&R statistical analysis was conducted to analyze the repeatability and reproducibility of the digital technique.Results Gage R&R showed a variability attributable to the digital technique of 3.8% (among the measures of each operator) and 4.5% (among operators) of the total variability; resulting repeatable and reproducible, since the variabilities were under 10%. In addition, statistically significant differences were shown at the wear volume (μm) of both the natural tooth as antagonist (p < 0.0001) and the screw-retained implant-supported metal-ceramic dental prostheses between 3- and 6-months follow-up (p = 0.0002).Conclusion The novel digital measurement technique results repeatable and reproducible to analyze the wear of screw-retained implant-supported metal-ceramic dental prostheses and natural tooth as antagonist.
Topics: Humans; Pilot Projects; Reproducibility of Results; Dental Implants; Ceramics; Bone Screws; Dental Prosthesis, Implant-Supported; Dental Restoration Failure
PubMed: 38310230
DOI: 10.1186/s12903-024-03881-y -
The Journal of Prosthetic Dentistry Apr 2024Technological advances in digital acquisition tools have increased the scope of intraoral scanners (IOSs), including scanning a removable complete denture (RCD) to...
STATEMENT OF PROBLEM
Technological advances in digital acquisition tools have increased the scope of intraoral scanners (IOSs), including scanning a removable complete denture (RCD) to replicate it. However, studies assessing the accuracy of IOSs for replicating a maxillary or mandibular RCD are lacking.
PURPOSE
The purpose of this in vitro study was to evaluate the accuracy (trueness and precision) of 3 IOSs while replicating a maxillary and mandibular RCD.
MATERIAL AND METHODS
One maxillary and 1 mandibular RCD were scanned with a desktop scanner (D2000) to obtain the reference model. Two operators scanned each RCD 5 times with 3 different IOSs (TRIOS 4, Primescan, and IS3800), following a predefined acquisition protocol. The 60 study models obtained were compared with the reference model using the Geomagic software program. For each comparison, the mean and standard deviation of discrepancy were calculated. Distances were measured on both the reference and the study model, and differences were calculated to assess whether sagittal or transverse deformations were present. The tolerance percentage of the volume of the digital model compared with the volume of the reference model was determined (difference tolerance was set at 0.1 mm). A univariate analysis of variance followed by a post hoc analysis using the Student-Newman-Keuls (α=.05) test was performed to determine the truest and the most precise IOS.
RESULTS
The TRIOS 4 and Primescan IOSs had comparable trueness, with mean dimensional variations of 47 ±27 µm and 57 ±8 µm respectively compared with the reference model. The IS3800 had a lower trueness (98 ±35 µm). Primescan was significantly more precise with a mean standard deviation of 64 ±15 µm (P<.05). The TRIOS 4 (141 ±48 µm) and IS3800 (129 ±24 µm) had comparable precision. Primescan showed the least sagittal and transverse deformation.
CONCLUSIONS
This study determined that an RCD can be replicated using an IOS, although all IOSs did not have equal accuracy. An in vivo study needs to assess whether this procedure is clinically acceptable.
Topics: Humans; Imaging, Three-Dimensional; Computer-Aided Design; Dental Impression Technique; Models, Dental; Dental Arch; Denture, Complete
PubMed: 38310062
DOI: 10.1016/j.prosdent.2024.01.011 -
Cureus Jan 2024The accuracy of definitive impressions has a significant impact on the quality of the final prosthesis. Elastic impression materials are commonly used in the traditional... (Review)
Review
The accuracy of definitive impressions has a significant impact on the quality of the final prosthesis. Elastic impression materials are commonly used in the traditional approach to replicate anatomical structures while indirectly fabricating prostheses. Digital impression has gained increasing popularity due to its various advantages, including three-dimensional previsualization, cost-effectiveness, and reduced time consumption. The objective of this study is to evaluate existing studies to provide an overview of the comparative advantages of digital impression techniques over conventional techniques. The review will focus on evaluating the accuracy, patient acceptability, operator preference, and time effectiveness of digital impression techniques in comparison to conventional techniques. The Population, Intervention, Comparison, and Outcome framework served as the basis for this study's search strategy. We conducted a comprehensive literature review by electronically searching articles published between 2000 and 2023 in PubMed, Medline, Cochrane, and the Web of Science. Furthermore, additional manual searches were conducted. The study examined the differences between optical impressions and traditional impressions in terms of accuracy, patient outcomes, and operator outcomes. It included both clinical and preclinical studies as well as randomized controlled trials. In conclusion, this review provides a short summary indicating that digital impressions exhibit comparable accuracy to conventional impressions without any statistically significant difference. This conclusion is based on an evaluation of accuracy, patient preference, and operator preference.
PubMed: 38304652
DOI: 10.7759/cureus.51537 -
The Journal of Prosthetic Dentistry Jan 2024Time and cost are factors that influence a patient's decision on dental prosthetic treatment. Evidence is needed to demonstrate that restoration using digital systems is... (Review)
Review
STATEMENT OF PROBLEM
Time and cost are factors that influence a patient's decision on dental prosthetic treatment. Evidence is needed to demonstrate that restoration using digital systems is more rapid and less costly than the conventional process.
PURPOSE
The purpose of this systematic review was to analyze and compare the duration and cost of fixed dental prostheses fabricated using digital and conventional methods from scanning or impression making to delivery of the prosthesis.
MATERIAL AND METHODS
A systematic review was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocol (PRISMA-P 2015) guidelines. The analysis methods and inclusion criteria were documented in a protocol registered in the Prospective International Register of Systematic Reviews (PROSPERO) (CRD42023458734). The bibliographic search was carried out using PubMed, Cochrane, and PROSPERO databases. The main keywords used were (Prosthodontic OR restorative dentistry OR denture) AND (CAD CAM OR Digital workflow OR Computer Dentistry OR Digital Design) AND (Economic OR cost OR Financial OR time efficiency). Two investigators undertook the different steps of article selection.
RESULTS
A total of 8 articles published between 2010 and 2023 were found for the qualitative synthesis by using the search criteria. Two studies showed that conventional impressions took more time than digital scans for the fabrication of a single crown, and 1 study showed the opposite. One study found that a digital scan was faster than conventional impression making for the fabrication of a 3-unit fixed partial denture, and another study showed the opposite. The dental laboratory technician spent more time on the conventional workflow than the digital workflow for the 3-unit framework and veneering process. No difference was found between conventional and digital workflows for clinical evaluation and chairside adjustment for the fabrication of a single crown. No articles have compared the cost of fixed prostheses.
CONCLUSIONS
The digital pathway can shorten the laboratory process. However, the duration of the impression or scan may vary depending on the technique used. Studies are needed to analyze the cost-effectiveness of the fabrication of tooth-supported restorations.
PubMed: 38302291
DOI: 10.1016/j.prosdent.2024.01.003 -
Journal of Indian Prosthodontic Society Jan 2024The purpose of this in vitro study was to comparatively evaluate the marginal and internal fits of cobalt-chromium metal custom post and core fabricated using a...
AIM
The purpose of this in vitro study was to comparatively evaluate the marginal and internal fits of cobalt-chromium metal custom post and core fabricated using a conventional technique with two digital techniques.
SETTINGS AND DESIGN
The study was designed in an in-vitro study setting.
MATERIALS AND METHODS
Five sets of custom post and core restorations were fabricated using the conventional (Group 1) and two semi digital methods (digital scanning of the resin pattern and computer aided additive manufacturing, and digital scanning of the silicone impression and subsequent computer aided designing [CAD] computer aided manufacturing fabrication) (Group 2 and 3). Marginal and internal fits of the posts were evaluated using a micro computed tomography scan at various points.
STATISTICAL ANALYSIS USED
A one way ANOVA test of the scores was made to evaluate the effect of different methods of custom post and core fabrication on marginal and internal fits. Bonferroni adjusted post hoc tests were conducted for intergroup comparison.
RESULTS
Least marginal gap was reported in Group 3 (82.5 ± 14.36 μm) followed by Group 1 (110 ± 25.19 μm) and Group 2 (112.5 ± 26.75 μm). Least internal gap at cervical, middle and apical as well as overall values were observed in Group 3 (78 ± 9.25 μm, 72 ± 7.79 μm, 160 ± 15.81 μm, 103.3 ± 4.43 μm) followed by Group 1 (113.5 ± 25.35 μm, 132.5 ± 19.92 μm, 502 ± 74.63 μm, 249.3 ± 25.44 μm) and Group 2 (114.5 ± 21.68 μm, 133.5 ± 19.57 μm, 598 ± 87.86 μm, 282 ± 28.91 μm) respectively. The results of one-way ANOVA and Bonferroni adjusted post hoc tests for marginal gap did not show any statistically significant difference between the three groups (P > 0.05) but revealed statistically significant difference (P = 0.02) in internal gap values at the cervical, middle, and apical regions as well as overall internal gap region between the three groups.
CONCLUSIONS
Better marginal and internal fits were observed in custom post and core fabricated by digital scanning of the silicone impression and subsequent CAD as compared to those fabricated by the other two groups.
Topics: X-Ray Microtomography; Research Design; Analysis of Variance; Chromium; Silicones
PubMed: 38263564
DOI: 10.4103/jips.jips_275_23 -
BMC Oral Health Jan 2024Developing competency in removable prosthodontics (RP) is challenging for undergraduate dental students because it involves threshold concepts and tacit knowledge....
BACKGROUND
Developing competency in removable prosthodontics (RP) is challenging for undergraduate dental students because it involves threshold concepts and tacit knowledge. Understanding this process can enhance learning and professional development in RP. The objective of this study was to identify the barriers hindering knowledge (threshold concept) and skill (tacit knowledge) development, and to propose strategies for achieving RP competency.
METHODS
Adopting critical theory, quantitative and qualitative approaches were implemented. The participants were third- to sixth-year dental students and recent dental school graduates. An online questionnaire was used to investigate the knowledge and skills required for achieving RP competency and barriers to RP competency development. Four focus groups were conducted to gather in-depth information. The data was analyzed using descriptive statistics and thematic analysis.
RESULTS
A total of 322 respondents completed the questionnaire (67% response rate), and 26 of them participated in focus group interviews. The four threshold concepts to achieve RP competency were the basic principles of RP, removable partial denture design, occlusion, and dental materials. The two main tacit knowledges were impression making and material handling skills. The curriculum should integrate strategies to assist dental students in overcoming intrinsic barriers such as self-experience, revision, and spatial-temporal relationship, along with extrinsic factors such as clinical correlations of content, discussions, and immediate feedback.
CONCLUSIONS
Threshold concepts and tacit knowledge in RP for undergraduate dental students have been proposed The strategies to overcome barriers comprise intrinsic and extrinsic factors that include the adoption of experiential learning. This study suggests effective teaching methods and learning strategies to maximize student learning and RP competency development when designing the undergraduate RP curriculum in dental education.
Topics: Humans; Prosthodontics; Students, Dental; Curriculum; Dental Care; Dental Occlusion
PubMed: 38263141
DOI: 10.1186/s12903-024-03874-x -
Journal of Clinical Medicine Jan 2024This study aimed to compare the clinical and radiographic outcomes of single posterior screw-retained monolithic implant crowns following a digital and conventional...
Clinical and Radiographic Outcomes of Single Implant-Supported Zirconia Crowns Following a Digital and Conventional Workflow: Four-Year Follow-Up of a Randomized Controlled Clinical Trial.
PURPOSE
This study aimed to compare the clinical and radiographic outcomes of single posterior screw-retained monolithic implant crowns following a digital and conventional workflow and to report on the survival/complication rate after a mean 4-year follow-up.
MATERIALS AND METHODS
Thirty patients with a single posterior tooth missing were rehabilitated with a bone-level implant. After a healing period of ≥3 months, they were subjected to both a digital and conventional workflow to fabricate two screw-retained monolithic implant crowns. The quantitative clinical adjustments to both crowns (intrasubject comparison) and a questionnaire were recorded at try-in. Thereafter, a crown of the digital and conventional workflows was randomly inserted. At the last follow-up, the marginal bone level (MBL), peri-implant health-related parameters (bleeding on probing (BoP), plaque, pocket probing depth (PPD)), and functional implant prosthodontic score (FIPS) were assessed. Furthermore, the implant survival and success rates and technical complications were evaluated.
RESULTS
A total of 27 patients were followed for a mean period of 4.23 ± 1.10 years. There was no significant difference between the digital and conventional workflows regarding clinical adjustments and questionnaire outcomes. More than twice as many participants recommended digital (n = 16) compared to conventional impressions (n = 7) to friends. The implant survival and success rate were 100% and 96.3%, respectively. Furthermore, two de-cementations and one fracture of the ti-base abutment occurred. There were no significant differences in BoP, plaque, and PPD metrics between the two groups. The changes in the MBL between implant crown insertion (baseline) and the last follow-up were 0.07 ± 0.19 mm and 0.34 ± 0.62 mm in the digital and conventional groups, respectively ( = 0.195). The mean overall FIPS score was 8.11 ± 1.37 (range: 5-10).
CONCLUSIONS
The clinical and radiographic outcomes of single screw-retained monolithic implant crowns were similar between both workflows after a mean of 4 years of service. The patients did not clearly prefer an impression technique for their restoration, although they would recommend the digital impression more often to friends. Thus, decision regarding clinical workflows may be based on the patient's and/or clinician's preference.
PubMed: 38256565
DOI: 10.3390/jcm13020432 -
Journal of Dentistry Mar 2024To measure the impact of the scanning distance on the accuracy of complete-arch implant scans acquired by using a photogrammetry (PG) system.
PURPOSE
To measure the impact of the scanning distance on the accuracy of complete-arch implant scans acquired by using a photogrammetry (PG) system.
MATERIAL AND METHODS
An edentulous cast with 6 implant abutment analogs was obtained. A brand new implant scan body was positioned on each implant abutment and digitized using an extraoral scanner (T710; Medit) and the reference file was obtained. Three groups were created based on the scanning distance used to acquire complete-arch implant scans by using a PG (PIC System; PIC Dental): 20 (20 group), 30 (30 group), and 35 cm (35 group). An optical marker (PIC Transfer, HC MUA Metal; PIC Dental) was placed on each implant abutment and a total of thirty scans per group were acquired. Euclidean linear and angular measurements were obtained on the reference file was obtained and used to compare the discrepancies with the same measurements obtained on each experimental scan. One-way ANOVA and Tukey tests were used to analyze trueness. The Levene test was used to analyze the precision values (α = 0.05).
RESULTS
Significant linear (P < .001) and angular trueness (P < .001) discrepancies were found among the groups. For linear trueness, Tukey test showed that the 20 and 30 groups (P < .001) and 30 and 35 groups were different (P < .001). For angular trueness, the Tukey test revealed that 20 and 30 groups (P = .003), 20 and 35 (P < .001), and 30 and 35 groups were different (P < .001) The Levene test showed no significant linear precision (P = .197) and angular discrepancies (P = .229) among the groups.
CONCLUSIONS
The scanning distance influenced the trueness of complete-arch implant scans obtained with the PG method tested. The maximum linear trueness mean discrepancy among the groups tested was 10 µm and the maximum angular trueness mean discrepancy among the groups tested was 0.02 .
Topics: Humans; Dental Impression Technique; Models, Dental; Computer-Aided Design; Imaging, Three-Dimensional; Mouth, Edentulous; Dental Implants
PubMed: 38246309
DOI: 10.1016/j.jdent.2024.104854 -
Journal of Contemporary Brachytherapy Dec 2023We report on methods and outcomes of post-operative endocavitary brachytherapy after prior irradiation and salvage surgery in a patient with maxillary alveolar squamous...
PURPOSE
We report on methods and outcomes of post-operative endocavitary brachytherapy after prior irradiation and salvage surgery in a patient with maxillary alveolar squamous cell carcinoma (SCC).
MATERIAL AND METHODS
A 67-year-old male with right maxillary alveolar SCC was referred for brachytherapy after prior definitive chemoradiotherapy and salvage posterior maxillectomy. A personalized endocavitary applicator was fabricated using dental impression plastic tray, vinyl polysiloxane paste, and four flexible catheters to deliver fourteen 3.5 Gy high-dose-rate fractions. High-risk and intermediate-risk clinical target volumes were treated to 3.7 Gy (D) and 2.4 Gy (D), with mandibular dose limited to 2.3 Gy (D) per fraction. These corresponded to total 2 Gy equivalent doses (EQD) of 72.8 Gy, 40.5 Gy, and 34 Gy, respectively.
RESULTS
The patient developed grade 2 mucositis and was disease-free for six months. He had biopsy-confirmed local recurrence at 8 months. He refused further treatment and expired within a month.
CONCLUSIONS
This simple approach to a personalized endocavitary applicator is feasible and allows for lower costs and less treatment delays, while ensuring patient comfort and convenience.
PubMed: 38230397
DOI: 10.5114/jcb.2023.133069 -
Heliyon Jan 2024There are very few studies using Benzalkonium Chloride (BAC) as an active disinfection agent for immersion techniques and there are no studies investigating the efficacy...
STATEMENT OF PROBLEM
There are very few studies using Benzalkonium Chloride (BAC) as an active disinfection agent for immersion techniques and there are no studies investigating the efficacy of repeated use of a disinfectant solution.
PURPOSE
This study evaluated an impression disinfectant by testing bacterial contamination of disinfectant batches used in a clinical setting after repeated use.
MATERIALS AND METHODS
Liquid samples were collected from impression disinfectant solutions used to disinfect dental impressions taken at a university dental clinic. The experimental samples (500 ml from 1 L of solution) were collected from teaching and professional clinics and the in-house commercial processing laboratory and stored at room temperature each day of clinic operation over five weeks. To determine to what extent the disinfectant efficacy of the active product decreased over time, the following tests were carried out: a. Inoculation b. Gram staining technique c. Matrix Assisted Laser Desorption/Ionization Mass spectrometry (MALDI- MS). Microbial growth was monitored and photographed. A culture revival was made from colonies grown on sheep blood agar, to isolate pure colonies incubated for 24 h at 37 °C. Each morphologically distinct type of colony was gram stained and MALDI spectrometry analysis was performed using the VITEK MS (BioMerieux Inc.).
RESULTS
Evidence of growth of bacteria was detected in teaching clinics' samples, and no growth from the professional clinic or the commercial laboratory.
CONCLUSIONS
The study demonstrated that the impression disinfectant solution tested is effective against common oral bacteria, despite some rare species such as and showing evidence of survival in solutions used for disinfection of impressions. However, in a high use teaching clinic environment its efficacy deteriorated. Though a second level disinfection protocol in the commercial laboratory-maintained impression disinfection.
PubMed: 38223712
DOI: 10.1016/j.heliyon.2023.e23792