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Abstract Background The advent of digital technologies has introduced novel methods for RPD fabrication, potentially enhancing the fit compared to the conventional approaches. This systematic review aimed to evaluate the methods to assess the accuracy of fit and precision of the RPD framework fabricated using conventional and digital (3D printed and milled) methods. Methods A comprehensive literature search (Registration Number CRD42023459566) was conducted across different electronic databases like PubMed/MEDLINE, Embase, Scopus, Web of Science, and Google Scholar. Studies investigating RPD fit and precision assessment using various techniques (Visual inspection and pressing test using silicone impression material, 3D digital analyses using a software, light microscopy, digital microscope at 50x, superimposition method /surface matching software program, µCT on silicone specimens and direct measurements) in in-vitro studies were included. Data extraction and quality assessment were performed to evaluate the methodological rigour of the selected studies. A narrative synthesis of the findings was carried out to evaluate the methods to assess the accuracy of fit and precision of the RPD framework fabricated through conventional and digital methods due to heterogeneity in study variables. Results Out of 413 records, a total of 8 in-vitro studies were included in this review. The key findings of the review suggest that RPD fit accuracy varies across fabrication processes including conventional techniques, resin milling, selective laser melting (SLM), and digital superimposition. Resin milling with polyether ether ketone (PEEK) offers the best accuracy. Among the different methods used in assessing the fit accuracy of the RPD framework silicone-based fit evaluation and superimposition techniques/ surface matching are commonly used methods. Conclusion Both traditional (non-computerized) and computerized methods for the assessment of fit and precision of conventional and digital RPD frameworks are used commonly. But still, formulation of a standard method for fit assessment of RPDs is warranted. In future with further refinements, digital methods would completely outperform the traditional methods.

Abstract Background This study aimed to evaluate the knowledge, awareness, and practice of intraoral scanners (IOS) and the factors affecting their accuracy amongst dental interns and practitioners. Methods This was an observational cross-sectional study in which data was collected from a representative population in Saudi Arabia, with the help of online questionnaires. The forms were distributed to 500 dental interns and practitioners and the questionnaire’s validity and reliability were evaluated for vetting and remarks. The questionnaire consisted of three parts: the participants’ demographic details, questions on the awareness and knowledge of participants regarding IOS, and the factors affecting the accuracy in clinical use of IOS. Questions were to be answered with ‘yes’, ‘no’ and ‘I don’t know’. Descriptive statistical analysis was performed using the control chart technique and the chi-squared test, with statistical significance set at p

Abstract Background Vinyl polyether silicone (VPES) is a novel impression biomaterial made of a combination of vinyl polysiloxane (VPS) and polyether (PE). Thus, it is significant to assess its properties and behaviour under varied disinfectant test conditions. This study aimed to assess the dimensional stability of novel VPES impression material after immersion in standard disinfectants for different time intervals. Methods Elastomeric impression material used –medium body regular set (Monophase) [Exa’lence GC America]. A total of 84 Specimens were fabricated using stainless steel die and ring (ADA specification 19). These samples were distributed into a control group (n=12) and a test group (n=72). The test group was divided into 3 groups, based on the type of disinfectant used - Group-A- 2% Glutaraldehyde, Group-B- 0. 5% Sodium hypochlorite and Group-C- 2% Chlorhexidine each test group was further divided into 2 subgroups (n=12/subgroup) based on time intervals for which each sample was immersed in the disinfectants – subgroup-1- 10 mins and Subgroup 2- 30 mins. After the impression material was set, it was removed from the ring and then it was washed in water for 15 seconds. Control group measurements were made immediately on a stereomicroscope and other samples were immersed in the three disinfection solutions for 10 mins and 30 mins to check the dimensional stability by measuring the distance between the lines generated by the stainless steel die on the samples using a stereomicroscope at x40 magnification. Results The distance measured in the control group was 4397.2078 µm and 4396.1571 µm; for the test group Group-A- 2% Glutaraldehyde was 4396.4075 µm and 4394.5992 µm; Group-B- 0. 5% Sodium hypochlorite was 4394.5453 µm and 4389.4711 µm Group-C- 2% Chlorhexidine was 4395.2953 µm and 4387.1703 µm respectively for 10 mins and 30 mins. Percentage dimensional change was in the range of 0.02 – 0.25 for all the groups for 10 mins and 30 mins. Conclusions 2 % Glutaraldehyde is the most suitable disinfectant for VPES elastomeric impression material in terms of dimensional stability and shows minimum dimensional changes as compared to that of 2% Chlorhexidine and 0.5% Sodium hypochlorite.

Abstract Background Developing efficient bonding techniques for orthodontic brackets and all-ceramic materials continues to pose a clinical difficulty. This study aimed to evaluate the shear bond strengths (SBS) of metal and ceramic brackets to various all-ceramic CAD-CAM materials, such as lithium disilicate CAD (LDS-CAD), polymer-infiltrated ceramic (PIC), zirconia-reinforced lithium silicate glass ceramic (ZLS), and 5YTZP zirconia after different surface treatments and thermal cycling. Materials and methods The samples were divided into two groups to be bonded with ceramic and metal lower incisor brackets. Each group was subdivided into a control group devoid of any surface treatment, 10% HF acid (HFA) etching, ceramic etch & prime (MEP), Al2O3 air abrasion, and medium grit diamond bur roughening. After surface treatment, brackets were bonded with composite resin cement, thermal cycled, and tested for shear bond strength. The failed surfaces were evaluated with a digital microscope to analyse the type of failure. The data were statistically analysed using a one-way ANOVA and Tukey HSD tests at p