Full Crown Research Articles

In vitro analysis of flowable and high viscosity bulk fill composite versus conventional composite in core build up of endodontically treated teeth.

This study aimed to test the load to fracture of flowable and high viscosity bulk-fill composites compared to a convetional (packable) composite used to build up pulpless teeth. 45 endodontically treated premolars were restored with fiber posts then divided into three groups (N = 15) according to the core build-up material. SDR group: (Smart Dentine Replacement), (BF): Filtek One Bulk Fill and (CC) Filtek Z350 packable composite. After core build up the teeth received full coverage crowns. Load to fracture (Newton) was recorded for each specimen. One-way ANOVA and Tukey multiple comparisons test were used. The highest load at fracture was shown by (CC) group (1067N), followed by (BF) group (879N), and the SDR group (838N). One way ANOVA and Tukey's multiple comparisons test demonstrated no significant differences between CC, SDR, and BF groups (p > 0.05). The three materials showed comparable load to fracture. Further studies with simulation to occlusal forces and oral temperature are required.

Advanced Adhesive Approach to Support a Minimally Invasive Full Mouth Rehabilitation.

Patients who exhibit severe loss of tooth structure are challenging to rehabilitate. Conventional treatment of these patients may require adjunctive procedures of surgical crown lengthening, elective endodontic therapy and placement of posts and cores to retain full coverage crowns as part of a full mouth rehabilitation. Minimally invasive approaches to treatment of these patients provides opportunity to conserve tooth structure and to reduce adjunctive procedures by using an advanced adhesive approach to retain all ceramic partial coverage restorations as part of a full mouth rehabilitation. The use of an advanced adhesive approach to perform a full mouth reconstruction restoring occlusal vertical dimension (OVD) is described. This approach emphasizes preserving healthy tooth structure, maximizing restoration adhesion to enamel and dentin, maintaining pulpal vitality and minimizing adjunctive dental procedures. The preparation design focuses on being defect-oriented to remove only diseased or undermined tooth structure. The all ceramic restorations are additive, where indicated, to further aid in preserving tooth structure. An advanced adhesive approach using an immediate dentin seal and resin coating over exposed dentin and composite resin cement under rubber dam isolation is used to lute the restorations. The restorations are fabricated using micro-layered lithium disilicate ceramic to maximize the esthetic appearance of the rehabilitation where needed. An advanced adhesive approach to full mouth rehabilitation should be considered as a treatment option for patients exhibiting tooth surface loss as an alternative to conventional full coverage restorations when clinical parameters allow.

Impact of Digital Manufacturing Methods on the Accuracy of Ceramic Crowns.

The purpose of this study was to assess the accuracy of full coverage crowns produced by two manufacturing methods: additive 3D printing and subtractive milling utilizing three different predefined cement spaces. Six groups were allocated based on the manufacturing method and the predefined cement space: printed wax with a 20 µm space (PW1); printed wax with a 50 µm space (PW2); printed wax with a 100 µm space (PW3); milled wax with a 20 µm cement space (MW1); milled wax with a 50 µm cement space (MW2); milled wax with a 100 µm cement space (MW3); milled zirconia coping with a 20 µm cement space (MZ1); milled zirconia coping with a 50 µm cement space (MZ2); milled zirconia with a 100 µm cement space (MZ3). All fabricated specimens were scanned using an Identica Blue 3D scanner and saved as standard tessellation language (STL) files. A triple scan method was performed using 3-matic software to assess accuracy. The discrepancy values were recorded in micrometers, and the analysis was conducted using one-way ANOVA. The wax printing method, with a cement gap design of 100 μm, demonstrated a significant improvement in the accuracy compared to the other methods (P<.01). In contrast, the zirconia milling method exhibited significantly lower accuracy relative to the other techniques (P<0.01). Moreover, different cement spaces resulted in various accuracy levels but the only statistically significant difference was observed for the 100 µm cement space in the printed wax group. The additive 3D printing method exhibited greater accuracy than the subtractive milling approach. Furthermore, altering the cement gap was found to impact the accuracy of both techniques, albeit without statistical significance. The accuracy of each CAM technique was investigated in this study, highlighting the promising accuracy of 3D-printed patterns for the lost-wax technique over direct crown milling. However, all methods produced reliable and accurate crown restorations.

Biomechanical assessment of zirconia-calcium silicate-silver composite dental crowns: A 3D finite element analysis study

Optimal dental health significantly contributes to an individual’s physical and psychological well-being, with an increasing focus on esthetics and functionality in dental restoration procedures. This research explores the use of zirconia ceramic materials combined with calcium silicate and silver compositions as an alternative for dental crown applications. The study employs 3D finite element analysis to assess stress distribution on full crowns with composites under axial and oblique loads, aiming to understand biomechanical aspects and identify fracture resistance and failure modes. The materials include zirconia-calcium silicate-silver composites with varying volume fractions (Zr 74 to 29%, Ca2SiO4 68 to 25%, and Ag 3 to1%). Results show stress concentration at the crown intaglio surface, influenced by the material’s elastic modulus. Specifically, the C14 composite crown with Young’s modulus 90.82 GPa exhibits lower stress levels for crown 10.9 MPa at axial load and 12.77 MPa at oblique load, making it a potentially recommended choice. These findings suggest the potential of designed biomaterials, emphasizing the importance of material selection in enhancing the longevity and resilience of dental crowns. Also, the study enhances understanding of biomechanical aspects in dental crown restorations, contributing valuable insights for clinical applications.

Lithium disilicate, full coverage crowns: what is the effect of using conventional impressions compared to digital impression with respect to the internal fit of the restoration? A systematic review.

Digital dentistry provides an alternative to fabrication of crowns. This systematic review focuses on the accuracy of the mean internal space of lithium disilicate crowns when comparing intraoral scanning to conventional impressions. Ovid Medline, Cochrane and PUBMED were searched and the review protocol followed the International Prospective Register of Systematic Reviews (PROSPERO) (CRD42023379908) and guided by The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Cohen Kappa coefficient confirmed the agreement of data. The revised Cochrane Risk of Bias tool was utilised to evaluate randomised controlled trials The Methodological Index for non-randomised controlled trials. Of the six in vivo studies, three concluded that digital techniques improved the internal fit over their conventional counterparts. Two found that there was no significant difference and one indicated that digital technique resulted in an inferior internal fit. Of the eight in vitro studies, two concluded digital techniques to be superior, two found digital techniques to be inferior and four found no significant difference. Significant heterogeneity between studies limits the potential any systematic review of the internal fit of dental crowns when comparing conventional and optical impressions. This systematic review indicates digital methodology is comparable to that of conventional impressions.

Utilizing 3D Model and Comparison Software Tools in Improving Assessment Methods: A Pilot Study

Purpose/Objectives: This manuscript investigates the effectiveness of computer-assisted design and manufacturing (CAD/CAM) technology in preclinical dental education. The COVID-19 pandemic created a need for remote teaching approaches. In preclinical fixed prosthodontics courses, traditional evaluation methods rely on faculty to visually grade laboratory projects utilizing rubrics and 2D images. Assessment and feedback vary amongst faculty, and faculty calibration has been inconsistent in reducing intra-and inter-rater variability. This study aimed to compare faculty assessment of student full coverage crown (FCC) preparations traditionally versus digitally through 3D model visual assessment and/or comparative analysis software reports. Methods: Eighteen UTHealth Houston School of Dentistry faculty participated, each randomly assigned into one of three assessment groups: traditional visual Group (TV), 3D Group (3D), and 3D visual assessment supplemented with comparative analysis software report (3D+) Group. Faculty graded the same eight lithium disilicate typodont preparations for all three assessment groups. Results: Survey results showed the ease of use and efficiency among the three assessment methods varied significantly. Grading scores revealed that axial wall reduction significantly differed among the three assessment methods. Conclusion: This study concludes that the combination of the two digital assessment methods can overcome the limitations of traditional evaluation methods and digital methods alone by providing objective feedback to students and enhancing their learning experience.

New intraoral digital impression with pneumatic gingival retraction used in the restoration of crown for posterior teeth: a case report

In fixed prosthodontics, clear exposure of the preparation margin is the prerequisite for obtaining accurate digital impressions and improving the marginal fit of restorations. To resolve the issues associated with the cord retraction technique, such as pain, acute injury, and prolonged procedural time, this study proposes a new technology for intraoral digital impression taking with pneumatic gingival retraction. The new scanning head blows a high-speed airflow that instantaneously separates the free gingiva, locally exposing the subgingival preparation margin. Combined with the farthest point preservation stitching algorithm based on the distance from the normal vector and high-speed laser scanning photography, it achieves global preparation edge data and gingival reconstruction, realizing painless, non-invasive, and efficient precise acquisition of the preparation margin. Using this new technique, a patient with a full porcelain crown restoration on a posterior tooth was treated. The digital impression revealed a clear margin of the preparation, and the crown made from this data has a good marginal fit.

Treatment of gingival recession in full crown by TUN

Treatment of gingival recession in full crown by TUN

Overlay: The successor for full coverage crown

Overlay: The successor for full coverage crown

Endocrown – a change of paradigm for restoring the endodontically treated teeth

Presently endocrowns are a suitable option for restoration of endodontically treated teeth primarily in molars. They are a less invasive procedure and achieve appreciate aesthetic and biomechanical results in comparison with conventional restorative procedures based on post-core and full coverage crown. The clinical success mostly depends on careful case selection and proper management of modern adhesive techniques.

Clinical Outcome of Indirect Bonded Porcelain Restoration Versus Full-Coverage Crown on Endodontically Treated Teeth in Posterior Areas: A Systematic Review.

The significant loss of tooth structure that occurs after dental caries and endodontic therapy is a common clinical challenge. Several methods were discussed in the literature to treat badly damaged teeth. This systematic review aims to compare the clinical outcomes of partial indirect bonded porcelain restorations to full-coverage crowns of endodontically treated teeth in posterior areas. The study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Data included in the review were identified through bibliographic research on electronic databases (PubMed/Medline, Google Scholar, Cochrane Library, and Web of Science). The strategy was applied by searching for randomized clinical trials (RCTs), cohort studies, and case-control studies using keywords (partial indirect bonded porcelain restoration, partial indirect bonded restoration, inlay and onlay, full convergent crown, and ceramic crown). Asa resultof a literature search through selected databases using the keywords, 88,421 papers were identified. A total of 671 articles were related and screened for inclusion and exclusion criteria. Four hundred and eighty-two articles that did not meet the inclusion criteria were excluded. A total of 189 full-text papers were assessed, and 20 articles were included in this study. Nineteen cohort studies and one case-control study were included and assessed in this review. This studyconcludesthat both full-coverage crowns and partial indirect bonded restorations demonstrate comparable survival rates. However, limited studies exist regarding partial indirect bonded restorations on endodontically treated teeth, indicating the need for further updated studies.

Long-term success of inlay and onlay procedures in dental repairs

Inlays and onlays are vital restorative techniques in dentistry, offering a conservative alternative to full crowns while preserving more of the natural tooth structure. These restorations, typically made from ceramic or composite resin materials, provide both aesthetic and functional benefits and are increasingly favored for their durability and longevity. In contrast to direct restorations, inlays and onlays are fabricated outside the mouth, allowing for greater precision and a more customized fit. The clinical success of these restorations largely depends on factors such as material choice, bonding technique, and patient-related variables like oral hygiene and habits. Ceramic materials are particularly noted for their resistance to wear and their ability to closely mimic the natural appearance of teeth, making them an attractive option for both patients and clinicians. Composite resins, while slightly less durable, offer a cost-effective alternative with satisfactory long-term results. Proper bonding techniques and high-quality materials are essential for ensuring the durability of inlays and onlays, with many restorations lasting over a decade. Patient-related factors also play a significant role in the success of inlays and onlays. Effective oral hygiene, regular dental check-ups, and the avoidance of habits like bruxism are essential for maintaining the integrity of these restorations over time. Despite the challenges and technical demands associated with their placement, inlays and onlays are highly successful when properly executed, offering patients a durable, aesthetically pleasing solution for dental repairs. The discussion of this review focuses on the critical elements that influence the long-term success of inlays and onlays, including material selection, clinical technique, and patient management, highlighting their effectiveness as a restorative option in modern dentistry.

Treatment Alternative of Molar Incisor Hypomineralisation for Young Permanent Teeth: A Scoping Review.

Treatment of Molar-incisor hypomineralisation (MIH) poses significant challenges for pediatric dentists due to its varied clinical manifestations and treatment needs. Understanding and evaluating different treatment options can improve patient outcomes. This study aimed to analyze available evidence on treatment options for restoring MIH-affected young permanent teeth. This scoping review followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses extension for Scoping Reviews (PRISMA-ScR) guidelines. A systematic literature search was conducted using Scopus, PubMed, and Science Direct databases, covering publications from 2014 to 2024. The search focused on therapies for young permanent teeth with MIH in children, employing predefined keywords and the Population, Concept, and Context framework. A total of 20 studies were included from Turkiye, Brazil, Syria, Germany, Egypt, and India. Thirteen articles examined first molars, five focused on incisors, and two covered both. The population studied ranged from 6 to 18 years old, involving up to 281 children and between 30 to 326 teeth. The study provides insights into various management and treatment approaches for MIH-affected teeth, along with the effectiveness and long-term stability of different methods and materials. Materials such as resin infiltration, SDF, HVGI, full metal crowns, SSC, lithium disilicate, zirconia crowns, and CAD/CAM ceramic restorations offer greater longevity and require less retreatment in managing MIH-affected teeth.

Evaluating the Effectiveness of the "Double Finish Line Technique" on Full-Crown Retention for Short Abutments: An In Vitro Study.

Achieving clinically adequate retention for cast crowns in prepared short abutments represents a major challenge for practicing dentists. Despite the important developments with adhesive cement, only a few teeth can be treated this way, and conventional preparation techniques are still employed for most crowns. Numerous options for auxiliary features exist; however, there is no consensus about one preferred method. This study aimed to evaluate the effect of a new innovative technique called the "double finish line technique" on full-crown retention for short abutments and to compare it with another modified preparation method. A comparative in vitro experimental study was conducted at the Department of Fixed Prosthodontics, Damascus University. The study sample consisted of 30 chromium-cobalt abutments and 30 metal crowns. The sample was divided into three equal groups. The first group was a control group (CG) with a 20-degree total occlusal convergence, 3 mm height, and a 0.5 mm chamfer finish line. The second group had a reduced total occlusal convergence (TOC) in the cervical 1.5 mm of the axial wall from 20 to 8 degrees. The third group implemented the so-called "double finish line technique," adding another 0.5 mm chamfer finish line 1 mm above the first finish line (DFL group). The metal crowns were cemented to metal dies with zinc-phosphate cement. Pull-off tests were applied until failure. Data were analyzed, and the differences between the three groups were detected using one-way ANOVA followed by Bonferroni's post-hoc tests (p<0.05). The mean tensile strength values for the specimens were 115.36 (SD=14.59), 149.60 (SD=11.10), and 42.46 (SD=11.54) for the TOC, DFL, and CR groups, respectively. The reduced total occlusal convergence and double finish line techniques effectively increased full crown retention and resistance cemented on short abutments.

Effects Of Some Climatic Factors On Soil Moisture In Scots Pine Stands With Different Crown Closure

In this study, the effects of climate factors on soil moisture in Scots Pine stands with different crown closure were investigated. As a result of the study, it was revealed whether soil moisture values differ in Scots Pine stands in the same aspect, depth and slope group. The effects of some climate elements (air temperature, air humidity and rainfall) on the soil moisture values in the areas where the Scots Pine in different crown closures were investigated. We took 6 different forest plots in the same depth, slope and aspect group. The average soil moisture values was found 23.91% in Open forest plot (POF), 26.84% in P1 plot (Low crown closure scots pine stand), 16.72% in P2 (Medium crown closure scots pine stand), 16.00% in P3 (Full crown closure scots pine stand), 30.79% in Simulation plot (PS) and 28.62% in Erosion plot (PE). It was determined that the lowest average soil moisture values were found in the P2 and P3 plots and the highest soil moisture values were in the PS and PE plots.

Treatment decisions of patients with Class II Division 2 malocclusion and severe tooth wear: a systematic review

BackgroundThe treatment strategy for patients with severe tooth wear associated with Class II Division 2 malocclusion remains a major challenge for dental practitioners.ObjectivesTo systematically review and summarize the literature on treatment strategies, restoration procedures and clinical outcomes for Class II Division 2 malocclusion patients with severe tooth wear.MethodsA literature review was conducted using Pubmed, Embase, the Cochrane Library, and Web of Science to identify eligible articles. Publications until October 16th, 2023 were searched independently and cross-checked by two researchers.ResultsOf 1513 articles screened, 10 reports detailed treatment processes, including six males and four females aged 34–68 years old. Four articles recorded pre-treatment freeway space (FWS) values ranging from 5 to 9 mm. All ten cases had significant occlusal vertical dimension (OVD) loss and the increase in OVD after treatment ranged from 1 to 7 mm. Pre-prosthetic orthodontic treatment was performed in two cases, in one of which only the maxillary region was orthodontically treated. The most common restorations provided were full coverage restorations. In most cases, temporary restorations were applied before the permanent restorations for eight weeks to six months. Four different sequences of final restoration were proposed. Follow-up ranged from four months to six years and included seven patients, one of them showed symptoms of temporomandibular disorder (TMD).ConclusionsA multidisciplinary team (MDT) approach to treatment is recommended. Consideration of pre-prosthetic orthodontic treatment is essential. Commonly used cephalometric measurements for anterior teeth include the interincisal angle and collum angle. The increases in OVD ranging from 1 to 7 mm can be effectively accommodated. Temporary restorations are recommended to accommodate the OVD, and the transition periods of 8 weeks to 6 months help the patients adapted well. Four different sequences for final rehabilitation have demonstrated positive clinical outcomes. Full crown restorations have emerged as the preferred choice for the ultimate restoration of these patients.

Removal of fiber post under the guidance of digital guide plate and one-piece glass fiber posts-and-cores repair: a clinical report.

This study explores the potential application of computer aided design (CAD)/computer aided manufac-turing (CAM) for one-piece glass fiber posts and cores in restoring tooth defects post-removal of a broken fiber post using a digital guide plate. This paper reports a fractured left upper incisor fiber post removed using a customized needle and digital guide plate. Following root canal retreatment, CAD/CAM integrated fiber post-core and zirconia full crown restoration were completed. The occlusion testing was conducted using the T-Scan Ⅲ system. This study offers insights for managing secondary repair after fiber post fractures.

Clinical applications and improvement of resin bonding for PEEK in resin-bonded fixed dental prosthesis: A review

Resin-bonded fixed dental prostheses (RBFDPs) are a commonly used precision treatment, such as fixed dental prosthesis (FDP) and implant-supported dentures. Full crown preparation of vital teeth, which is required for traditional FDPs, may result in a risk of pulp reaction as a large portion of the coronal tooth structure must be removed. RBFDP has been recognized as a non-invasive or minimally invasive treatment modality for the replacement of single missing teeth. RBFDPs require much less tooth preparation than conventional FDPs. These dental treatments are restorative solutions used to cover missing teeth and achieve an aesthetic smile. The biomechanical rules, aesthetics, polishability, and bond strength have been emphasized in RBFDP treatments. Polyetheretherketone (PEEK) is one of the most widely used biomaterials in dentistry. The material, which stands out especially with its acceptable aesthetics, biocompatibility and modulus of elasticity close to dentin, has enabled it to be used in RBFDP treatments. Since PEEK is lighter than metal alloys, patients experience less discomfort and a feeling closer to natural teeth. Furthermore, the thermoplastic properties of PEEK are claimed to provide a precise fit, allowing the restoration to better integrate into the natural tooth structure. In addition, its ability to be customized using different modern manufacturing techniques is thought to offer dentists and patients a reliable option for successful long-term treatment. Our review is about the use of PEEK material as an alternative material in RBFDPs with low negative effects on periodontal tissues and their bonding with resins.

The Effect of Student Experience and Tooth Location on Finish Line Width and Angle of Full Metal Crown Preparations in Preclinical Setting.

To determine the effect of experience and tooth location on the finish line width and angle of crown preparations performed by undergraduate students. Eighty full metal crown preparations on typodont teeth were divided into four groups: Group 1: 20 preparations performed on mandibular first molar in the first semester. Group 2: 20 preparations performed on mandibular first molar in the second semester. Group 3: 20 preparations performed on mandibular second molar in the first semester. Group 4: 20 preparations performed on mandibular second molar in the second semester. All prepared teeth were scanned, and the finish line width and angles were measured at 8 different locations. Paired t-test in the SPSS software was used to compare and determine the effect of experience and tooth location on the students' performance. There was a statistically significant difference in the mandibular first molar finish line width between the first and second semesters for the same student in the distal, distolingual, and mesiobuccal areas of the tooth. There was a statistically significant increase in finish line width between first and second molars in the distobuccal, distal, distolingual, lingual, and mesial side of the tooth. Regarding the finish line angle, there was a statistically significant difference between the first and second semesters on the distal side of the tooth. There was a statistically significant increase in finish line angle between first and second molars in the distobuccal side of the tooth. As students gain more experience in different types of tooth preparations, they tend to produce a wider finish line than that recommended for full metal crown preparation. The tooth location in the mouth influences the width and angle of the finish line hence the more inaccessible areas on the tooth have a wider finish line.

Impact of common social habits on optical properties of lithium disilicate glass ceramic crowns: An in vitro study

Statement of the problemPatient stratifications considered the stability of color and treatment longevity are key success of restoration. Daily consumption of colored beverages, such as coffee, tea, and soft drinks, as well as the use of globally consumed materials, such as smokeless tobacco (ST), snuff, Khat, and Yerba mate, can change the color of restorative materials, such as lithium disilicate glass ceramics (LDGC). These changes can ultimately lead to treatment failure. PurposeThis in vitro study aimed to evaluate color changes, translucency, and opalescence of full anatomical LDGC crowns exposed to commonly used and potentially colorant solutions. Materials and methodsNinety LDGC specimens/crowns were prepared and divided into nine groups according to immersion solution (control, Saudi Coffee, Cola, Khat, Yerba mate, Nescafe, ST Snuff, and Mixed Fruit Juice). The specimens were immersed in colorant solutions for 15 days with alternating twice daily at 37 °C. Color parameters were measured with a spectrophotometer and calculated using two backgrounds (black and white). Data were subjected to ANOVA followed by the Student t-test and Bonferroni test at a significant difference level (α = 0.05). ResultsThe greatest color change (ΔE*) among groups after immersion was observed in Yerba mate (7.6 ± 1.6). The mean difference of before and after staining within Yerba mate group was 3.14 ± 1.6 (p = 0.001). Translucency mean values of groups after immersion into staining media were ranging between 7.6 ± 1.2 and 9.1 ± 2, showing a slight decrease compared with pre-staining values but was not significantly different. Immersion in Mixed Fruit Juice significantly reduced opalescence (7.4 ± 1.9) compared to (8.8 ± 1.7) before staining. ConclusionThe findings confirm that appropriate user guidance helps to preserve both translucency and opalescence as well as prevent color changes. This can improve patient compliance and promote treatment longevity.