Indirect Restorations Research Articles

Long-term Survival Rate and Clinical Quality of Individually Layered Indirect Composite Restorations in Adolescents and Young Adults.

To evaluate the survival and clinical quality of individually layered indirect composite restorations (ICRs) in the mixed and permanent dentition at two study centers. A total of 155 adhesively cemented ICRs in 34 participants (aged 6 to 50 years and treated between 2008 and 2018) were evaluated for survival and clinical quality. All were individually layered restorations fabricated from laboratory sculptable composites by a specialized dental technician. Two calibrated independent investigators examined and graded each restoration as success, survival with repair, or failure based on the FDI criteria. The marginal quality and gap width of the restorations were analyzed by scanning electron microscopy. The periodontal health of treated teeth (TT) was evaluated in comparison with that of unrestored control teeth (CT) by measuring the pocket depth (PD), clinical attachment level (CAL), sulcus bleeding index (SBI), and the modified Turesky Plaque Index (TPI). A serial t-test (p 0.05) was used for statistical analysis of periodontal parameters. Success and functional survival rates were calculated using the Kaplan-Meier method. Molar incisor hypomineralization (MIH) was the most common indication for treatment (41%). The median age at treatment was 14.9 years (68%-CI: 7.7-29.5). The median service time of the restorations was 5.7 ± 3.4 years. 132 restorations were classified as a success, 21 as survival with repair, and 1 as a failure. The success rates at 1, 5, and 10 years were 95.4%, 87.4%, and 78.8%, respectively, and the corresponding functional survival rates were 100.0%, 98.9%, and 98.9%. The clinical quality, encompassing esthetic, functional, and biological criteria, was rated as excellent or good in over 90%. Periodontal response, however, was the only criterion showing worse results since restored teeth (TPI = 1.9) had significantly more plaque than CT (TPI = 1.7; p = 0.0001). No significant differences were observed in PD, CAL, or SBI. The mean marginal gap width was 135.7 µm and 63.8% of the restorations had perfect margins. ICRs are suitable for minimally invasive restoration of large tooth structure defects in the developing dentition of children and adolescents and for long-term temporary restoration of the adult dentition.

Comparative Analysis of Modern 3D-Printed Hybrid Resin-Ceramic Materials for Indirect Restorations: An In Vitro Study

The study investigated the impact of aging on surface roughness, color stability, and biocompatibility of hybrid resin-ceramic materials. A total of 225 specimens were produced from three three-dimensional (3D)-printed (HarzLabs Dental Sand Pro (HL), BEGO VarseoSmile Crown plus (BV), Voco V-Print c&b temp (VV)) and one milled material (Voco Grandio Blocs (VG)). Specimens were grouped into untreated, polished, and glazed surfaces. 5000 thermal cycles simulated aging. Surface roughness and color stability were analyzed, and surface topography was observed using scanning electron microscopy (SEM). Biocompatibility was evaluated with L929 cells. Surface roughness differed significantly between untreated and other groups, with no changes before and after artificial aging. Untreated milled samples were significantly smoother than 3D-printed ones. SEM analysis revealed roughest surfaces in untreated 3D-printed specimens. Polished and glazed specimens were smoother than untreated ones. Color values showed significant differences between untreated and treated/aged groups. No material showed cytotoxicity. In summary, untreated VG was smoother than 3D-printed materials, but polishing and glazing reduced roughness to levels comparable to VG. Surface treatments induced color changes, with glazing causing more changes than polishing. Aging affected color stability and biocompatibility but not surface roughness. All materials showed acceptable color changes and good biocompatibility.

Success and Survival of Composite Resin Restorations for the Management of Localized Anterior Tooth Wear: A Systematic Review and Meta-Analysis.

To systematically review the literature and assess the success and survival rates of anterior composite restorations used in the management of anterior tooth surface loss, and to estimate complete posterior occlusion re-establishment when a Dahl approach is utilized. An electronic search was performed in the following databases: MEDLINE via Ovid and Scopus, for articles published from 1970 to November 2020. The systematic review was performed according to the PRISMA and Meta-analyses guidelines. Only randomized and non-randomized clinical trials, and Cohort studies that involved the exclusive use of direct/indirect anterior composite restorations for the management of localized anterior tooth wear were included. From the 724 studies identified through the initial search, six studies fulfilled the inclusion criteria and were included in the review; three prospective and three retrospective. In total, 141 patients received 1068 direct and indirect composite restorations. Follow-up periods ranged between 5 months and 10 years. The survival rate for anterior composite resin restorations reported in this review was 88% (95% CI: 70% to 98%) over a period of 2 and 10 years; however, high heterogeneity was observed amongst included studies; (I² = 97%). Sensitivity analysis reported survival rates of these restorations of 93% (95% CI: 85% to 98%) over a period of 2 and 7 years, (I² = 83%). Success rates were reported for these restorations of 68% (95% CI: 44% to 87%) over a period of 2 and 10 years, high heterogeneity; (I² = 98%). The success of composite Dahl in re-establishing posterior occlusion was 85% (CI: 73% to 94%). The result of this systematic review and meta-analysis support the use of anterior composite restorations as a short-medium term option for the management of tooth wear. In the long-term, patients should be informed that these restorations will require monitoring, repairs, or replacements.

COMPARATIVE ANALYSIS OF STRESS-STRAIN STATE OF SINGLE-ROOTED TEETH DURING INDIRECT RESTORATION OF THE CROWN WITH STUMP INLAYS OF DIFFERENT DESIGNS

The aim of our study on the biomechanics of the tooth inlay is to select the most efficient design of stump pin inlay for indirect restoration of single-rooted teeth. Materials and methods. To implement the aim of the study, the biomechanics research was conducted in the following four designs of stump inlays: 1 - traditional, 2 - with a single-stage change in the diameter of the pin along its length, 3 - with a two-stage change in the pin along its length, and 4 - with a single-stage change in the diameter of the pin and a cap in the crown of the tooth, covering the end of the root. The mathematical modeling was performed using the common software MSC NASTRAN for finite element analysis. The package, with the help of which the elastic three-dimensional models of the dentition are built and analyzed based on the finite element procedure, determines the displacement of each node of the finite element along the axis system, with three coordinates, normal and tangential stresses, as well as equivalent Huber-Mises stresses, which are calculated according to the well-known formula of deformable solid mechanics Results. The minimum values of equivalent stresses in both the pin inlay and the dentin of the root of the tooth at the level of the apical end of the pin inlay occur when using a pin inlay with a one-stage change in the diameter of the pin and a cap on the crown of the premolar. At the same time, the values of equivalent stress in dentin at the level of the apical end of the inlay pin are closest to the maximum values of equivalent stresses observed on the surface of the root of the tooth (differences do not exceed 10%). The maximum values of equivalent stresses in both the pin inlay and the dentin of the root of the tooth at the level of the apical end of the pin inlay occur when using a pin inlay of conventional design. In this case, the difference in the values of equivalent stresses in the pin compared to the inlay with a one-stage change in the diameter of the pin and a cap is 9%, and in the dentin at the level of the apical end of the inlay pin, the difference in stresses is 10%. The maximum values of equivalent stresses in both the dentin of the root of the tooth to be restored and the pin of the stump inlay occur when applying a traditionally used pin inlay. Among the various pin inlays considered, a stump inlay featuring a single-stage change in the diameter of the pin and a cap on the crown of the tooth to be restored demonstrates the highest efficiency, yielding the lowest equivalent stresses in the dentin of the tooth's root.

Perspectives of general dental practitioners on restoring endodontically treated molars: a UK-based vignette study.

Aims To assess and compare how UK general dental practitioners (GDPs) restore endodontically treated molars and what tooth-related factors they consider relevant to their management.Method An online cross-sectional vignette survey was sent out to UK dentists via email and the use of social media platforms. Three clinical cases were designed.Results In total, 394 participants completed the survey. GDPs showed a preference towards restoring the endodontically treated molars with indirect restorations, such as crowns and onlays. Material selection varied, with a notable inclination towards gold and lithium disilicate. This was influenced by factors such as the number of remaining tooth walls, thickness of walls and the presence of parafunction.Conclusion Clinicians generally agreed on whether to place a direct or indirect restoration but there was greater disagreement when deciding on the type of restoration and material. Further evidence and education are required to help UK dentists decide more objectively whether to place an onlay or a crown, what material to select and what prognostic factors are most pertinent to the case.

Dentists’ Treatment Decisions Concerning Restorations in Adult Patients in North Norway: A Cross-Sectional Tromsø 7 Study

Plain Language SummaryA randomized population of adults over 40 years, selected among the citizens of Tromsø County in North Norway, were examined by dentists, resulting in a study group of 3,653. Clinical examinations were executed, clinical photos and X-rays taken of each patient in a dental clinic. This is part of the Tromsø 7 study. A specially designed data programme was developed, and 17 trained dentists were able to assess the clinical state of restorations. All the dentists were working as clinical teachers in dental schools. The purpose was to decide what kind of treatment they thought best for unacceptable restorations. Should they be replaced or repaired if revision was needed. Only 3.3% of all examined teeth were proposed for restoration revision, which seemed to be rather low. Among the suggested revisions, approx. 25% were recommended for repair, while 75% was assigned for replacement. Tooth-coloured material, i.e., composite, was recommended in almost 75% of the cases. Different kinds of crowns counted for 25%. A considerable difference in the number of treatment suggestions was noted among the dentists. Statistical analyses demonstrated that 16% of the difference in suggestions for restoration re-treatment depended on different dentist opinions. Secondary caries and restoration fracture were found to be the most used indications for re-treatment. Need for restoration revision seems low in North Norway. However, there is a tendency towards larger and more indirect restorations. The diagnosis of secondary caries is still a matter of uncertainty.

3D-Printed Permanent Resin Crowns on Pre-Molar and Molar Teeth; Two-Year Results of a Prospective Clinical Study.

The aim of this prospective clinical study was to evaluate the 12 and 24-month clinical results of overlay and one-piece endodontic crown restorations applied with additively manufactured 3D printed permanent ceramic-filled resin (PCR) according to the Modified US Public Health Service (USPHS) criteria. A total of 33 indirect restorations (16 overlay, 17 endocrown) (4 premolar, 29 molar) produced using PCR (Formlabs) were applied to 30 patients by a single dentist. The restorations were evaluated according to the modified USPHS criteria at baseline (7 days), 12 and 24 months times by two independent evaluators. The study registration number is NCT05168852. In the comparisons of the dependent criteria scores, the Related Samples Cochran Q test was used, and in post-hoc paired comparisons, the Bonferroni test. The Fisher-Freeman-Halton test was applied in the comparisons of categorical variables according to the restoration type groups (α = 0.05). No statistically significant difference was determined between the evaluation criteria scores at baseline, 12 months, and 24 months for the marginal adaptation (P=0.05), retention (P=1), interproximal contact (P=0.368), color match (P=1), surface texture (P=1), and patient satisfaction (P=1). The only score criteria that showed a statistically significant difference between baseline and 24 months (P=0.001) among all other criteria was marginal discoloration. This criteria's score change was from 100% A score to 69.7% A score. In the 2-year follow-up of indirect single-tooth restorations produced with 3D-printed PCR, all restorations showed acceptable clinical performance. (≥99.5%A+B score at 2 years).

Biomimetic Capabilities of Lithium Disilicate Glass-Ceramic Restorations on Posterior Teeth: Evaluation of the Long-Term Survival Rate—A 10-Year Follow-Up

In contemporary dental practice, clinicians have a variety of materials and options for restoring single teeth compromised by carious or non-carious diseases. According to studies and new concepts in biomimetic restorative dentistry, indirect ceramic restorations will play an increasingly important role in daily practice. We follow up and evaluate clinically three times over a 10-year period on eighty-six indirect restorations (n = 86) of lithium disilicate e.Max Press (Ivoclar, Schaan, Liechtenstein) in 32 patients. Restorations are evaluated in the 2nd, 5th, and 10th years after the fixation. Four of the restorations studied (n = 86) had to be replaced at year 5 follow-up because of fracture (failure rate: 4.65%; Kaplan–Maier). There are no restorations with bulky, cohesive fractures. Lithium disilicate ceramic restorations provide a good treatment alternative for a 5- to 10-year period of observation, and they can be successfully applied in dental practice in 91.73% to 98.84% of cases. Advancements in digital dentistry, including the use of intraoral scanners and CAD/CAM technology, are set to further refine the precision and efficiency of indirect restorations for distal teeth, enabling quicker turnaround times and improved fit. Additionally, ongoing developments in biomaterials promise to enhance the durability and biocompatibility of these restorations, potentially leading to better long-term success rates and patient satisfaction. The goal of this clinical study was to look at how well biomimetic ceramic overlays and onlays made of lithium disilicate held onto teeth with a IV-generation adhesive system for 10 years. The study also looked at how well the edges of the teeth adjusted and how strong the teeth were overall.

The Influence of Different Pontic Designs on Fracture Resistance of Implant-supported Fixed Partial Dentures Anchored in Polyurethane Simulating Bone-blocks of Two Different Densities: An In Vitro Study.

This study aimed to evaluate the fracture resistance of implant-supported fixed partial prostheses fabricated from monolithic zirconia with different pontic framework designs and anchored in different bone-like simulation models of two different densities. A total of 60 implants were anchored in two different in vitro bone simulation models of two different densities, namely, solid polyurethane foam blocks, 20 and 10 pounds per cubic foot (PCF) to construct implant-supported fixed partial dentures (FPDs), the pontic constructed to replace missing second premolar and first molar. Thirty models were constructed and then divided into two groups according to anchoring material D2 (n = 15) and D3 (n = 15). Each group of models was subdivided into three groups according to pontic design (n = 5). Each model was tested against fracture in a universal testing machine. The data were analyzed with a two-way univariate ANOVA and Tukey HSD test (α = 0.05). The results were statistically analyzed, and the values were considered significant at p≤0.05. The findings showed that neither change in pontic design nor change in bone type has a significant influence on the fracture resistance of the prostheses (p > 0.05). All the tested materials fell within the acceptable range for functioning under mastication, with a slight change in resistance when the pontic design was changed. Zirconia is considered the material of choice when planning implant-supported FPDs because of its high fracture strength values. Within the limitations of this study, the pontic design and synthetic polyurethane bone-simulating model had no effect on the fracture resistance of four-unit implant-supported FPDs. This study postulated that any pontic design could be used in four units of implant-supported FPDs according to functional and aesthetic needs, as long as the histological nature of the alveolar bone falls within the D2 or D3 bone type. How to cite this article: Othman MS, Abu-Eittah MRH. The Influence of Different Pontic Designs on Fracture Resistance of Implant-supported Fixed Partial Dentures Anchored in Polyurethane Simulating Bone-blocks of Two Different Densities: An In Vitro Study. J Contemp Dent Pract 2024;25(7):684-690.

Management of subgingival proximal defects

Deep proximal cavities can be progressively elevated by a restorative procedure known as deep margin elevation (DME), which improves margins for either direct or indirect restorations. Dietschi and Spreafico (1998) introduced the non-surgical alternative procedure of DME for crown lengthening. Other names for the DME concept include “coronal margin relocation,” “proximal box elevation,” and “cervical margin relocation.” A DME treatment’s therapeutic effectiveness depends on a proper indication, and its clinical efficacy is largely dependent on how well the DME is adjusted. In addition to maintaining periodontal health, a suitable DME adaption may be able to lessen bacterial buildup and the occurrence of secondary caries. Here, we report on three cases of DME that were performed when adequate isolation was possible, and caries was progressing subgingivally.

Comparison of the microtensile bond strength of direct and indirect resin restorations in the cervical region

ObjectivesTo evaluate in vitro the adhesion system of direct and indirect composite resin restorations in enamel and dentin, in cavities made in the cervical region using microtensile bond strength (μTBS) and to observe the most recurrent types of failure in the different groups. MethodsStandardized cavities were made in the line of the cementoenamel junction (CEJ) in 36 selected human premolars, which were randomly divided into 2 groups. In the Indirect Restorations (IR) group, indirect restorations were cemented in composite resin, using a universal adhesive and dual resin cement, performing selective enamel etching (SEE). In the Direct Restorations (DR) group, direct restorations were made in composite resin, performing SEE and bonding with the universal adhesive. Each specimen was sliced into sections measuring approximately 1 mm2, with enamel and dentin adhesion divided into subgroups DRe, DRd, IRe, and IRd. The sections were subjected to the μTBS test to assess bond strength in both enamel and dentin, comparing direct and indirect restorations in the cervical region. The types of failure in each group were also observed. ResultsThere was no statistically significant difference in μTBS between the DRe and IRe groups (p = 0.314) and also between the DRd and IRd groups (p = 0.145). There was a predominance of adhesive failures. ConclusionsThe bond strength of composite resin restorations was found to be equivalent in enamel and dentin, whether applied directly or indirectly. There was a predominance of adhesive fractures followed by cohesive resin fractures. Clinical significanceThe choice between direct and indirect restorations in the cervical region may consider patient preferences, but with caution, as clinical factors such as operator skill, specific tooth conditions and case complexity are crucial, and both techniques exhibit comparable bond strength.

Bacterial Adhesion and In Situ Biodegradation of Preheated Resin Composite Used as a Luting Agent for Indirect Restorations.

To evaluate surface roughness and bacterial adhesion after in situ biodegradation of the cementation interface of indirect restorations cemented with preheated resin composite. Resin composite blocks (Z250XT/3M ESPE) were cemented to bovine enamel (7 × 2.5 × 2 mm) using preheated microhybrid resin composites: (1) Filtek Z100 (3M ESPE) (Z100); (2) Gradia Direct X (GC America) (GDX); and (3) Light-cured resin cement RelyX Veneer (3M ESPE) (RXV) (n = 21). The resin composites were preheated on a heating device (HotSet, Technolife) at 69°C for 30 minutes. Disk-shaped specimens (7 x 1.5 mm) were made for biodegradation analysis with the luting agents (n = 25). The in situ phase consisted of 20 volunteers' using an intraoral palatal device for 7 days. Each device had six cylindrical wells for the blocks and the disk-shaped specimens. Biodegradation was evaluated through surface roughness (Ra), scanning electron microscopy (SEM) micromorphological analysis, and colony-forming unit (CFU) count. The film thickness of the luting agents was also measured under stereomicroscopy. Increased surface roughness was observed after the cariogenic challenge without differences between the luting agents. Higher variation and surface flaws suggestive of particulate detachment were observed for Z100. No differences were observed in CFU counts. All materials underwent surface biodegradation, and the surface roughness of the resin cements was similar to or lower than that of the preheated resin composites. The resin composites' film thickness was thicker than that of the resin cement. Clinicians should be aware of these factors when choosing the use of preheated resin composite since it can lead to reduced longevity of the cementation interface and, therefore, restorations.

Survival and Complication Rates of Polymer-Infiltrated Ceramic-Network Single- Tooth Restorations with an Observation Period of up to Three Years.

This study evaluated the clinical performance of a polymer-infiltrated ceramic-network (PICN) material for up to 3 years. Patients (N=286) received 581 indirect restorations as crowns (417), overlays (131), and inlays/veneers (33) fabricated using the PICN (VITA Enamic) by CAD/CAM procedures using intraoral scanning (Cerec Omnicam) and milling systems (Cerec MC XL). The restorations were evaluated annually and in case of complications. Data were analyzed using Kaplan-Meier estimate. Complications were classified as biological or technical failures. Until final recall (mean observation period: 18.3 months) with a dropout rate of 4.8%, 3 biological and 10 technical complications were observed. The overall success rate of the placed restorations was 97.7%. Biological complications included pulpitis and pulp necrosis. Technical complications were debonding (n=7) and fracture (n=3). PICN materials can be used as an alternative to lithium-disilicate or zirconium dioxide for single tooth reconstructions, providing that early failures included debonding and fractures.

PREVALENCE AND QUALITY OF RESTORATIVE STRUCTURES OF PERMANENT TEETH IN CHILDREN FROM LOWLAND AND MOUNTAINOUS AREAS OF THE TRANSCARPATHIAN REGION OVER THE COURSE OF OBSERVATION

Introduction: Treatment of invasive forms of caries involves the removal of demineralized hard tooth tissues and the restoration of anatomical integrity using various types of restorative materials. The choice and conditions of use of these materials have clear indications. However, the durability of restorative structures, even with strict adherence to the algorithm, is not always sufficient, especially among children living in areas with biogeochemical deficiencies. Objectives: The aim of this study was to analyze the prevalence of fillings made from different restorative materials in the permanent teeth of children living in lowland and mountainous geographical areas of the Transcarpathian region and to determine the percentage of defects in restorative structures over time. Methods: For the analysis, 525 medical records of dental patients (form 043) from two geographical areas of the Transcarpathian region were selected, specifically from Uzhhorod, University Dental Clinic LLC, and Rakhiv, the dental office of the Rakhiv District Hospital. The period of dental treatment covered was from 2018 to 2022. Paraclinical content analysis was performed to determine the number of direct and indirect restorative structures and to assess the occurrence of defects and their loss at 6 and 12 months post-treatment. Statistical probabilities and errors were determined using the computer program STATISTICA 6.1. Results. The rates of patient visits for the restoration of indirect restorations of permanent teeth in children living in the mountainous zone differ from those in children from the lowland zone of residence significantly after 6 months (4.0%; 2.1%; p<0.05), and not significantly after 12 months (10.0%; 10.5%; p>0.05). Comparing the incidence of defects, impaired fixation, or loss of various types of restorative structures in permanent teeth in children living in lowland and mountainous areas of the Transcarpathian region, it was found that the most common defects or loss of fillings made of glass ionomer cements occurred both after 6 and 12 months. The percentage distribution of the appearance of defects or loss of restorative structures made in the permanent teeth of children living in the mountainous zone from glass ionomer cements, light-curing composites on indirect restorations is 6 months (7.2%, 6.0%, 4.0%, p>0.05) and 12 months (16.3%, 11.1%, 10.0%, p>0.05). The differences are not significant. In the permanent teeth of children living in the low-lying area, the percentage of defects or loss of restorative structures made of glass ionomer cements, light-curing composites on indirect restorations is 6 months (6.7%, 4.4%, 2.1%, p<0.05) and 12 months (20.0%, 9.6%, 10.5%, p<0.05). The differences are significant. Conclusions: Thus, when comparing the percentage of defects in various restorative structures and their loss in the permanent teeth of children living in the lowland and mountainous areas of the Transcarpathian region, no significant differences were found. Specifically, for glass ionomer cements, the defect percentages were 6.7% and 7.2% after 6 months (p > 0.05) and 20.0% and 16.3% after 12 months (p > 0.05). For direct composite restorations, the defect percentages were 4.4% and 6.0% after 6 months (p > 0.05) and 9.6% and 11.1% after 12 months (p > 0.05). For indirect composite restorations, the defect percentages were 2.1% and 4.0% after 6 months (p > 0.05) and 10.5% and 10.0% after 12 months (p > 0.05). This indicates that the differences in the percentage of defects between the lowland and mountain zones are not statistically significant for any of the types of restorative structures during the specified periods.

Effect of immediate dentin sealing on the fracture strength of indirect posterior restorations:Systematic review and meta-anlysis protocol.

Background Immediate Dentin Sealing (IDS) is a technique that applies an adhesive layer immediately after tooth preparation, prior to the placement of indirect restorations. This method is gaining attention due to its potential to improve the bond strength and mechanical properties of restorations, particularly in the posterior region where restorations endure significant masticatory forces. The objectif of this systematic review and meta-analysis is to evaluate the effect of IDS on the fracture strength of indirect posterior restorations. Methods Following PRISMA guidelines, a comprehensive literature search was conducted in four databases: Web of Science, Scopus, Cochrane Library, and PubMed. Inclusion criteria focused on in vitro studies involving human teeth with indirect posterior restorations, published between 2014 and 2023. Studies using IDS were compared to those using conventional methods. The risk of bias was assessed using the Cochrane Collaboration’s tool, and a meta-analysis was performed with a random-effects model. The standard mean difference and 95% confidence intervals were calculated to compare fracture strength, with I2 statistics assessing heterogeneity. Forest and funnel plots were employed to visualize results and publication bias, respectively. Discussion The results indicate that IDS generally enhances the fracture strength of indirect posterior restorations, particularly with ceramic materials like lithium disilicate. However, the effectiveness of IDS varies depending on the material and restoration type. While some studies demonstrated improved fracture resistance with IDS, others showed minimal benefit, especially with composite restorations. Additionally, IDS improved marginal adaptation and internal fit but increased the risk of severe failures, such as root fractures. Systematic review registration PROSPERO: CRD42024584545 (Registered on 08/09/2024).

The Effects of Different Restoration Materials on the Trueness of Intraoral Scanners

Aim: This study aimed to assess how different restoration materials affect the trueness of intraoral scanners. Materials and Methods: Artificial teeth on a typodont model were prepared for crowns and fixed partial dentures (FPDs) using full metal, monolithic zirconia, and porcelain-fused-to-metal (PFM) materials. Each group underwent 10 scans with a Trios intraoral scanner, generating 60 STL files. A reference scanner created a master model using scanning spray to reduce reflection errors. The STL files were aligned with reverse engineering software for comparison and were analyzed in micrometers (μm) using Root Mean Square (RMS) and Mean Distance measurements. The Levene test and two-way ANOVA with Post Hoc analysis were used for statistical evaluation. Results: The RMS deviations for the FPDs were 77.9 ± 15.2 μm (full metal), 84.6 ± 6.9 μm (monolithic zirconia), and 130 ± 19.7 μm (PFM). For the crowns, the RMS values were 76.9 ± 6.5 μm (metal), 71 ± 8.2 μm (monolithic zirconia), and 153 ± 22.4 μm (PFM). The mean distance deviations for the FPDs were 11.4 ± 4.8 μm (metal), 11.2 ± 3.4 μm (monolithic zirconia), and 18.3 ± 2.6 μm (PFM). For the crowns, the mean distances were 8.6 ± 3.4 μm (metal), 10.2 ± 3 μm (monolithic zirconia), and 24.7 ± 3.3 μm (PFM). Significant differences were noted in the PFM groups. Conclusion: Restoration materials notably affected intraoral scanner trueness, especially PFM restorations. The restoration length did not significantly affect the accuracy.

Options for replacing a single lost anterior tooth in a dentition with reduced periodontal health

To restore comfort, function, and esthetics while maintaining occlusal stability, restoring a single missing anterior tooth in a periodontally impaired dentition is a significant task. An implant-supported crown, traditional three-unit fixed partial denture (FPD), cantilever FPD, resin-bonded FPD, or removable partial denture can be considered in a normal, healthy dentition; however, problems with mobility and poor periodontal support of the remaining dentition may make these procedures unfeasible options as it might be difficult to avoid overloading of the implant in periodontal compromised adjacent teeth, difficult to achieve proper esthetics with conventional FPD, to maintain the stability of dental arch with acrylic resin removable partial dentures is not possible and incidences of frequent debonding of resin bonded FPD are high when abutments are mobiles. Fiber-reinforced composite resin FPD is often effective in these clinical situations to provide a conservative therapy option to restore the patient’s ease and esthetics by limiting mobility.

Oral Health-Related Quality of Life Improvement After Treatment With Fixed and Removable Dental Prostheses.

Missing teeth negatively affect oral functions and masticatory efficiency, which in turn can reduce a person's quality of life (QoL). This study is aimed at evaluating the effect of dental prostheses on oral health-related quality of life (OHRQoL) in adults. This is an observational study to measure patients' OHRQoL using a cohort study design before and after treatment with different dental prostheses (fixed and removable). Ninety-seven patients who received dental prostheses responded to a questionnaire before dental prosthetic treatment and then after the completion of the treatment. The conduction was face-to-face or via telephone interviews. The questionnaire is divided into two parts to verify the demographic and the patient's related factors and to measure OHRQoL using the Oral Health Impact Profile-5 (OHIP-5). Descriptive statistics, inferential statistics, and multivariable analysis were conducted using Stata Statistical Software: Release 14.2 (2016; StataCorp LLC, College Station, Texas, United States) and were at a 0.05 significance level. Data were collected from the 97 patients, of which 70% were male with a mean age of 39.5 and 30% were female with a mean age of 43. The educational level showed that only 15% of the patients received a bachelor's degree and that the remaining 85% stopped at a high school general educational level. The received prosthetic treatment consisted of 23% single crowns, 29% fixed partial dentures (FPD), 20% removable partial dentures (RPD), and 28% complete dentures. Self-reported overall health indicated that 64% of the patients had very good health and 36% had good health or a lower quality of health. There was a significant difference in OHIP scores before prosthetic treatment (M=5.4, SD=0.57) and after prosthetic treatment (M=3.2, SD=0.49) with no significant difference in the reduction in OHIP scores between fixed prostheses (M=-2.8, SD=0.64) and removable prostheses (M=-1.5, SD=0.74). The amount of improvement in OHIP answers after wearing a prosthesis was significant (p<0.0001). Linear regression indicated that having a history of discomfort from general oral health improved (decreased OHIP score) by 2.2 after prosthetic dental treatment compared to participants without a history of general oral health discomfort when all other variables are held constant. Within the limitations of this study, it can be concluded that restoration of missing teeth with a dental prosthesis has an immense impact on individuals' QoL, regardless of the type of dental prosthetic restoration.

Performance of large language artificial intelligence models on solving restorative dentistry and endodontics student assessments

ObjectivesThe advent of artificial intelligence (AI) and large language model (LLM)-based AI applications (LLMAs) has tremendous implications for our society. This study analyzed the performance of LLMAs on solving restorative dentistry and endodontics (RDE) student assessment questions.Materials and methods151 questions from a RDE question pool were prepared for prompting using LLMAs from OpenAI (ChatGPT-3.5,-4.0 and -4.0o) and Google (Gemini 1.0). Multiple-choice questions were sorted into four question subcategories, entered into LLMAs and answers recorded for analysis. P-value and chi-square statistical analyses were performed using Python 3.9.16.ResultsThe total answer accuracy of ChatGPT-4.0o was the highest, followed by ChatGPT-4.0, Gemini 1.0 and ChatGPT-3.5 (72%, 62%, 44% and 25%, respectively) with significant differences between all LLMAs except GPT-4.0 models. The performance on subcategories direct restorations and caries was the highest, followed by indirect restorations and endodontics.ConclusionsOverall, there are large performance differences among LLMAs. Only the ChatGPT-4 models achieved a success ratio that could be used with caution to support the dental academic curriculum.Clinical relevanceWhile LLMAs could support clinicians to answer dental field-related questions, this capacity depends strongly on the employed model. The most performant model ChatGPT-4.0o achieved acceptable accuracy rates in some subject sub-categories analyzed.

Prevalence of Decay and Tooth Condition Changes Adjacent to Restored Dental Implants: A Retrospective Radiographic Study.

This study examined the association between a dental implant and changes in adjacent teeth over time. Electronic health records of 1818 patients who received a dental implant were retrospectively evaluated over 14 years (2005-2019) in a university setting. The status of the adjacent tooth and vertical and horizontal distance from the implant platform to adjacent teeth were determined using digital intraoral radiographs taken at baseline and the last follow-up visit (1-14 years, median 4 years). In total, 1085 dental implants were evaluated. There were 234 instances of a change in the adjacent tooth. Decay was observed in 83 (7.6%) of adjacent teeth; the mean time to development was 4 years (range 1-14 years). Approximately 9% of adjacent teeth received direct restorations, 4.8% received indirect restorations, 1% received endodontic root canal treatment, and 5.6% were extracted. The mean horizontal distance between the implant platform and the adjacent teeth was 3.56 mm; the mean vertical distance from the contact point to the alveolar crest on the tooth side was 6.2 mm at the first time of the reported decay on X ray. These distances did not significantly influence the occurrence of caries. The prevalence of interproximal contact loss was higher on the mesial of the implant crown at 63% compared with 20% on the distal side. This large retrospective analysis identified that teeth adjacent to a dental implant were at risk of decay and changes in their condition. In addition, the implant-to-tooth distance and inadequate emergence profile may contribute as caries risk factors in addition to hygiene and a high sugar level diet. These findings appear essential for clinicians when making treatment decisions and discussing outcomes with patients.