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Indian Journal of Dental Research :... Oct 20233D printing technology is replacing manual fabrication in all fields. 3D-printed impression trays should be assessed as they could replace conventional impression trays... (Comparative Study)
Comparative Study
BACKGROUND
3D printing technology is replacing manual fabrication in all fields. 3D-printed impression trays should be assessed as they could replace conventional impression trays in the future.
AIM
In-vitro comparison and evaluation of the dimensional stability and retention strength of impressions to custom impression trays fabricated using conventional method and additive technology.
MATERIALS AND METHODS
A maxillary edentulous auto-polymerizing acrylic resin model served as the master model. Two moulds were prepared from the master model in order to obtain 12 casts. One cast was scanned for 3D printing digital light processing (DLP) and fused deposition modelling (FDM) 24 impression trays using polylactic acid (PLA). Twelve casts were used to fabricate light cure impression trays. Polyvinyl-siloxane impressions were made on the master model using 36 impression trays and 18 trays each were used to assess dimensional stability and retention strength.
RESULTS
In dimensional stability analysis, one sample t-test revealed a statistically significant difference between each group and the master model followed by a one-way ANOVA. There were significant differences, but the difference was less with FDM trays (P < 0.05). In retention strength analysis, one-way Analysis of variance (ANOVA) revealed statistically significant difference between each group and post-hoc test revealed specific difference, the highest with FDM trays (P < 0.05).
CONCLUSION
Dimensional changes were observed at 30 minutes and 72 hours. Lesser dimensional changes were observed when impressions were made using FDM trays followed by DLP and light cure trays. The mean retention strength seen in descending order was FDM, followed by DLP and light cure trays. The best retention strength was noticed when impressions were made using FDM trays.
Topics: Dental Impression Technique; Dental Impression Materials; Printing, Three-Dimensional; Polyvinyls; Siloxanes; Humans; In Vitro Techniques; Models, Dental; Materials Testing
PubMed: 38739826
DOI: 10.4103/ijdr.ijdr_519_23 -
BMC Medical Education Mar 2024Despite the updated guidelines on dental impression disinfection protocols during the COVID-19 pandemic, adherence to such procedures has not been studied among dental...
Knowledge, attitude, and practice of dental health professionals toward dental impression disinfection protocol during the COVID-19 pandemic in Saudi Arabia- a cross-sectional study.
BACKGROUND
Despite the updated guidelines on dental impression disinfection protocols during the COVID-19 pandemic, adherence to such procedures has not been studied among dental health professionals in Saudi Arabia. Understanding DHPs' knowledge, attitudes, and practices regarding COVID-19 is crucial in assessing a willingness to adhere to the recommendations provided by health authorities in mitigating the spread of COVID-19 via dental impressions impacting patient safety and infection control measures. Hence, this study aimed to assess dental health professionals' (DHPs) knowledge, attitudes, and practices (KAP) toward dental impression disinfection protocol during the COVID-19 pandemic in Saudi Arabia.
METHODS
A cross-sectional study using an online survey was conducted from 14 December 2022 to 21 March 2023 among practicing dentists, dental assistants (DA), dental laboratory technicians (DT), and dental hygienists in Saudi Arabia. A validated and reliable questionnaire that consisted of 38 items along with demographic variables was prepared to collect the data. Using Google Forms, a questionnaire link was prepared and shared on the social media platforms of DHPs in Saudi Arabia. A descriptive analysis was conducted to report the percentages and frequencies. The mean knowledge, attitude, and practice scores were analyzed using an Independent t-test, ANOVA, and Pearson's correlation tests.
RESULTS
A total of 718 DHPs voluntarily participated in the survey. Most of the DHPs exhibited average knowledge 392 (54.6%), neutral attitudes 393(54.7%), and adequate 549 (76.5%) practice towards dental impression disinfection protocol. The mean knowledge score differed significantly across nationality (p = 0.013), type of DHPs (p < 0.001), qualification (p = 0.045), and experience (p = 0.028) of the study participants. Significant differences in attitude towards impression disinfection were observed in different age groups (p = 0.002), qualifications (p = 0.015), and experiences (p = 0.024) of the DHPs. Similarly, practice varied across different age groups (p = 0.010), nationality (p = 0.013), type of DHPs (p = 0.019), qualification (p = 0.044), experience (p = 0.041), and COVID-19 Infection (p = 0.006). Moreover, a significant positive correlation between knowledge-attitude (r = 0.258, p < 0.01), knowledge-practice (r = 0.283, p < 0.01), and attitude-practice (r = 0.196, p < 0.01) was observed.
CONCLUSION
DHPs considered in this study demonstrated average knowledge and attitudes toward impression disinfection, requiring improvement through continuous dental education and training. However, they displayed acceptable dental impression disinfection practices during the COVID-19 pandemic. It is highly recommended that continuing education programs should mainly reinforce the knowledge of sodium hypochlorite, iodophor, and phenolics and their concentrations to be used as an impression disinfectant. Additionally, it should focus on techniques of disinfecting elastomeric, hydrocolloid, zinc oxide and eugenol, and impression compound materials to mitigate the spread of COVID-19 based on Saudi ministry of health guidelines.
Topics: Humans; Disinfection; COVID-19; Cross-Sectional Studies; Saudi Arabia; Health Knowledge, Attitudes, Practice; Pandemics
PubMed: 38448923
DOI: 10.1186/s12909-024-05238-z -
Medical Science Monitor : International... Nov 2023BACKGROUND The aim of this study was to assess and compare the vertical/horizontal dimensions and occlusal accuracy of non-working/opposing casts obtained from three...
BACKGROUND The aim of this study was to assess and compare the vertical/horizontal dimensions and occlusal accuracy of non-working/opposing casts obtained from three different impression materials and 3D print cast. MATERIAL AND METHODS Dentulous Master models simulating a case of a fixed dental prosthesis were mounted on an articulator (control group). Opposing mandibular casts obtained from three different impression materialsand 3-dimensional print constituted test groups , ,and , respectively. Three points, anterior vertical (AV), posterior vertical (PV), and anteroposterior (AP) were compared for dimensional accuracy among casts. Occlusal accuracy was analyzed on Medit Link software at 3 teeth (#13, #17, and #27). After calculating means for each group, the differences were calculated at probability value of P≤0.05 using the single-sample t test, ANOVA, and Tukey test. RESULTS The dimensions were significantly different from those of the mounted master models except in Gp AL(E) and Gp AL(F) at AV dimension and Gp AL(E) at AP dimension (P>0.05). A statistically significant difference of the error of means among the 4 tested groupswere detected only at 2 dimensions (AV and PV) between the Gp AL(E) and Gp 3D-C and between Gp AL(F) and Gp 3D-C groups. Other groups showed no significant differences. CONCLUSIONS The opposing casts obtained from the extended-pour alginate and alginate alternative impression materials showed higher occlusal accuracy compared to conventional alginate and 3D printed casts.
Topics: Humans; Alginates; Mandible; Models, Dental; Printing, Three-Dimensional; Software
PubMed: 37924203
DOI: 10.12659/MSM.941654 -
Polymers Apr 2024The impression materials utilized today in dental medicine offer a good reproducibility and are easily accepted by patients. However, because they are polymer-based,...
The impression materials utilized today in dental medicine offer a good reproducibility and are easily accepted by patients. However, because they are polymer-based, they have issues regarding their dimensional stability. In this respect, the present work proposes a new type of dental impression, which is reinforced with rigid mouthguards. The aim of the study is to test the performances of such new impressions by comparing them to conventional ones-from this critical point of view, of the dimensional stability. Three types of polymeric materials were considered for both types of impressions: alginate, condensation silicone, and addition silicone. In order to obtain the new type of impressions, a manufacturing technique was developed, comprising the following phases: (i) conventional impressions were made; (ii) a plaster model was duplicated, and 15 rigid mouthguards were obtained; (iii) they were inserted in the impression technique, with each mouthguard positioned on the cast before the high-consistency material was inserted in the tray and the practitioner took the impression; (iv) the mouthguard remained in the tray and the low-viscosity material was inserted over the mouthguard; (v) the impression was positioned on the model, and after the material hardened, the mouthguard-reinforced impression was analyzed. In the evaluation of the dimensional stability, rigorous statistical analysis was essential to discern the performance differences between conventional and mouthguard-reinforced dental impressions. Statistical analyses employed non-parametric Mann-Whitney U tests because of the non-normal distribution of the data. They indicated a statistically significant improvement in the dimensional stability of addition silicone impressions when reinforced with mouthguards ( < 0.05), showcasing superior performance over conventional methods. Conversely, alginate and condensation silicone reinforced impressions did not exhibit the same level of stability improvement, suggesting the need for further optimization of these materials. In conclusion, from the three considered elastomers, addition silicone was found to be the prime candidate for high-precision dental impressions, with the potential to improve their quality from conventional impressions by utilizing the proposed reinforcing technique.
PubMed: 38611252
DOI: 10.3390/polym16070994 -
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 -
British Dental Journal Aug 2023Aims To develop an optimal clinical and laboratory protocol for the fabrication of 3D printing dentures.Design A prospective feasibility study across three UK dental...
Aims To develop an optimal clinical and laboratory protocol for the fabrication of 3D printing dentures.Design A prospective feasibility study across three UK dental schools.Material and methods Each patient received one conventional and one 3D-printed denture. Both dentures were constructed using the same impression, jaw registration and wax trial denture. Variables investigated included methods of digitisation of the impression and optional use of a 3D-printed baseplate for jaw registration.Results Clinicians strongly preferred 3D-printed baseplates. Patients felt that conventional and printed dentures were similar in retention and stability. More patients favoured conventional dentures over 3D-printed dentures in terms of comfort.Discussion It is feasible to combine conventional clinical work with digital techniques to produce 3D-printed dentures. 3D-printed baseplates offer a cost-effective alternative to conventional bases at the jaw registration stage. Challenges were faced in tooth positioning and managing occlusion, particularly where roots required adjustment.Conclusion 3D printing is suitable for producing baseplates for jaw registration blocks and wax trial insertions. It is feasible to produce 3D-printed dentures using conventional clinical techniques for impressions, jaw registration and wax trial insertion. The workflow used in this study for 3D-printed dentures is not superior to conventional dentures. Further work is required.
PubMed: 37558770
DOI: 10.1038/s41415-023-6114-0 -
European Journal of Dentistry May 2024This study evaluated the linear dimensional change of polymerization of three materials and two techniques of the union of molding transfers for implant-supported...
OBJECTIVES
This study evaluated the linear dimensional change of polymerization of three materials and two techniques of the union of molding transfers for implant-supported prostheses used in the open-tray technique.
MATERIALS AND METHODS
A nylon maxilla-shaped matrix was made, two osseous integrated implants were installed, and, over these two, straight conical mini-pillars were installed. Open-tray impression transfers were attached to the mini-pillars, and a silicone guide was made to standardize the connections between the transfers. The samples were divided into six groups ( = 20): PA (Pattern Resin LS, chemically activated acrylic resin in the single step technique); DU (Durallay, chemically activated acrylic resin in the single step technique); BI (Protemp4, bisacrylic resin in the single step technique); PAC (Pattern Resin LS in sectioning and joining of segments technique); DUC (Durallay, in sectioning and joining of segments technique); and BIC (Protemp4, in sectioning and joining of segments technique). The linear dimensional change values that occurred among these transfers were measured in a profile projector (VB300; Starret) coupled to the Quadra Check device, with a resolution of 0.001 mm, performed by a single calibrated operator.
STATISTICAL ANALYSIS
Data were submitted to a two-way analysis of variance and Tukey's test ( < 0.01).
RESULTS
Statistically significant mean values were found in all comparisons. The PA showed the lowest mean values (µm) of linear dimensional change, both in the single-step technique and in the sectioning and joining technique, in the following order: BI 255.73 (3.81), DU 173.75 (2.30), PA 95.97 (3.20), BIC 23.82 (1.71), DUC 20.85 (2.53), and PAC 13.27 (2.09). The single-step technique showed the worst results, regardless of the material.
CONCLUSION
The sectioning and joining technique reduced the dimensional change in all materials, and the Pattern Resin LS showed the lowest shrinkage mean values, followed by Durallay and Protemp4.
PubMed: 38806161
DOI: 10.1055/s-0044-1779422 -
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 -
JPMA. the Journal of the Pakistan... Oct 2023To determine the current trends in complete denture education in undergraduate dental colleges.
OBJECTIVE
To determine the current trends in complete denture education in undergraduate dental colleges.
METHODS
The survey-based study was conducted in April and May 2020 at undergraduate dental colleges of Pakistan, and comprised heads of the Prosthodontics Department at all dental colleges across Pakistan having at least one batch of final year dental students. Data was collected using an online predesigned questionnaire that explored theoretical and practical teaching patterns of complete denture prosthodontics in the undergraduate years, and the materials and practices of students when constructing complete dentures in the clinics. The participants were given the option of choosing more than one option where needed. Data was analysed using SPSS 23.
RESULTS
Of the 49 subjects approached, 40(81.6%) returned the forms duly filled; 11(27.5%) from public-sector institutions and 29(72.5%) from the private sector. There were 26(65%) institutions which required that their undergraduate students fabricate 2-4 conventional complete dentures. In all 40(100%) colleges, faculty gave live clinical demonstrations before students fabricated conventional complete dentures in the outpatient departments. Teaching strategy included small group discussions in 25(62.5%) institutions. Green stick 40(100%), zinc oxide eugenol 40(100%) and impression compound 39(97.2%) were the materials of choice for various steps of impression making. In all the 40(100%) institutions, students fabricated conventional complete dentures during their prosthodontics rotation. Immediate, copy and overdentures were constructed by students in 8(20%), 3(7.5%) and 8(20%) institutions, respectively.
CONCLUSION
Majority of the dental schools used similar impression materials and techniques for fabricating conventional complete dentures. Didactic teaching of conventional and unconventional complete dentures was being carried out at a huge majority of the dental institutions studied.
Topics: Humans; Curriculum; Pakistan; Education, Dental; Schools, Dental; Denture, Complete; Students
PubMed: 37876065
DOI: 10.47391/JPMA.9710 -
Plastic and Reconstructive Surgery Feb 2024Documenting complex three-dimensional (3D) cleft lip and palate malformation with plaster casts based on maxillary impressions is standard care. Presurgical orthopedic...
Documenting complex three-dimensional (3D) cleft lip and palate malformation with plaster casts based on maxillary impressions is standard care. Presurgical orthopedic treatment also requires an impression. Digital impression-taking in patients with cleft lip and palate is feasible, but procurement costs hinder clinical implementation. Individualized impression trays allow for a precise impression, limiting airway risk. The authors present an open-source impression tray library with scalable impression trays not requiring 3D modeling knowledge. The cleft lip and palate impression tray library is accessible on Open Science Framework. Different shapes are available, and the tray size is selected based on the tuber distance. This allows 3D printing with biocompatible material at the point of care complying with local regulations. The open-source cleft tray library presented offers a hybrid solution for cleft centers, pending the implementation of digital impression.
Topics: Humans; Cleft Lip; Cleft Palate; Workflow; Printing, Three-Dimensional; Dental Impression Technique
PubMed: 37184464
DOI: 10.1097/PRS.0000000000010684