Anterior Restorations Research Articles

Comparative analysis of different filling materials in deciduous teeth

Dental caries in pediatric patients presents a significant challenge in maintaining oral health, making the choice of filling materials for deciduous teeth crucial for long-term success. Various restorative materials, including composite resins, glass ionomer cements (GICs), and resin-modified glass ionomers (RMGICs), have been used, each with distinct properties regarding durability, biocompatibility, and aesthetic outcomes. Composite resins are well-regarded for their ability to closely match the natural color of teeth, making them ideal for anterior restorations. However, they are technique-sensitive and may not provide sufficient durability in posterior regions subjected to high stress. Glass ionomer cements, known for their ease of placement and fluoride release, offer functional benefits in high-caries-risk patients, despite their lower aesthetic quality and susceptibility to wear over time. Resin-modified glass ionomers attempt to combine the strengths of both composites and GICs by improving durability and aesthetics while maintaining the fluoride-releasing property. The safety and biocompatibility of these materials also play a pivotal role in pediatric dentistry. While composite resins may release small amounts of bisphenol A (BPA), which has raised concerns about its potential health risks, GICs and RMGICs are generally considered safer due to their simpler chemical composition and fluoride release. In terms of functional longevity, composite resins offer better wear resistance compared to GICs, though resin-modified glass ionomers provide a compromise with improved strength and ease of use. Ultimately, the choice of restorative material should consider the specific clinical circumstances, including the child’s caries risk, tooth location, and the balance between aesthetic and functional needs. No single material is universally ideal for all cases, and a tailored approach is necessary to optimize outcomes in pediatric dental restorations.

Four-year Outcomes of Class III and IV Anterior Restorations Based on a Subset of German Health Insurance Data.

Numerous studies report on the outcome performance of posterior composite restorations. However, there are fewer studies providing data for anterior restorations. The aim of this study was to evaluate the clinical outcome performance of anterior permanent restorations by analyzing a large dataset from a German national health insurance company. Routine claims data from a major German national health insurance company were assessed. Fee codes were used for tracing restoration careers on a day-count basis. The treatment was defined as a placed restoration (Class III and IV) on a mesial or distal tooth surface, irrespective of the extension. The restorations were placed between January 1, 2010 and December 31, 2013. Statistical analyses were conducted using Kaplan-Meier survival analysis to determine cumulative 4-year survival rates. The primary outcome was re-intervention on the same surface. Secondary outcomes were crowning and extraction which were analyzed separately. A total of 2,417,791 restorations involving mesial surfaces and a number of 2,409,031 restorations involving distal surfaces were observed. At 4 years, the cumulative survival rates concerning the primary outcome 're-intervention' were 79.9% for mesial and 80.9% for distal restorations. The respective annual failure rates (AFR) were 5.5% and 5.2%. Four-year survival rates for the secondary outcome 'crown' were 93.8% for mesial and 94.1% for distal anterior restorations. The respective AFRs were 1.6% and 1.5%. For the secondary outcome 'extraction,' the respective rates were 94.6% for mesial and 93.9% for distal restorations. The respective AFRs were 1.4% and 1.6%. The performance of permanent anterior restorations which were placed in general dental practices in Germany can be rated as acceptable.

Evaluating the Success of Preformed Resin Bonded Composite Strip Crowns for the Primary Central Incisor in Restoring Carious Primary Canine Teeth: A Retrospective Analysis.

Background Restoration of primary canine teeth in pediatric dentistry requires a balance of functional, biological, and esthetic factors. Stainless steel crowns, while effective for posterior restorations, often have patient acceptance issues due to esthetic limitations. Resin-bonded composite strip crowns have gained traction for anterior restorations due to their superior esthetic qualities and repairability. However, their long-term performance in primary canines characterized by unique morphological and functional demands has not been thoroughly evaluated. This study investigates the efficacy of resin-bonded incisor strip crowns in primary canines over three years, assessing their functional durability, biological integrity, and esthetic performance to provide a comprehensive evaluation of their long-term success in this application. Methods This retrospective observational study, conducted from September 2023 to December 2023 at the Department of Pediatric and Preventive Dentistry, Saveetha Dental College and Hospitals, Chennai, Tamil Nadu, India, received ethical approval from the Institutional Human Ethical Committee (IHEC/SDC/PEDO-2103/23/131). Dental records from January 2020 to December 2020 were reviewed by two investigators to identify children aged six years or younger who had undergone pulpectomy in primary canine teeth and were restored with resin-bonded incisor strip crowns. Exclusions included records with missing contact details or post-treatment radiographs. The purpose was to ensure a three-year review period when contacting patients in 2023. Eligible parents were contacted by phone, informed about the study, and invited for a review. Informed consent was obtained in person. Children with exfoliated primary canines and those whose parents did not sign the consent form were excluded. The restored crowns were evaluated using World Dental Federation (FDI) criteria across functional, biological, and esthetic domains by two calibrated examiners. Statistical analysis was conducted using IBMSPSSStatistics for Windows, Version 24 (Released 2016; IBM Corp., Armonk, New York, United States), with categorical variables expressed as n (%), inter-examiner reliability assessed by Cohen's kappa, and chi-square test used for goodness of fit, setting significance at 95%. Results Of the 92 primary canines restored with resin-bonded incisor strip crowns, 60 children were evaluated. The retention rate at the three-year follow-up was 50 (83.3%). Functional evaluation revealed that 48 (80%) of crowns maintained surface texture, 42 (70%) preserved form and contour, and 52 (86.6%) demonstrated acceptable occlusion and wear. Biologically, 55 (91.7%) of the crowns had no secondary caries, and 56 (93.4%) had no dental hard tissue defects at the margin. Esthetically, 48 (80%) of crowns retained surface texture, 46 (76.6%) had a satisfactory color match, and 45 (71.6%) exhibited minimal marginal staining. Statistical analysis confirmed significant results for all functional and esthetic parameters (p < 0.05). Conclusion The technique of placing incisor strip crowns in the place of primary canines can be recommended considering its maintenance of functional, biological, and esthetic properties.

EVALUATION OF BOND STRENGTH OF NEWER BONDING AGENTS TO HUMAN DENTIN AFTER SIX MONTHS OF STORAGE AN ANALYTIC STUDY

Introduction: Among various materials, composite resins have been developed in order to provide the best aesthetics to the anterior restorations as well as for posterior restorations. Resin-dentin bonds are more difficult to achieve than resin-enamel bonds, because dentin bonding relies on organic components. Materials &amp; Methodology: A total number of 44 extracted human mandibular premolars were collected. Occlusal enamel surface was removed using an airotor and diamond bur.The collected 44 teeth were divided in to four groups according to the bonding agents used. 1st sub group with five teeth that is submitted for microtensile testing within 24 hours and SEM analysis for failure mode, 2nd sub-group contains five teeth which is submitted to microtensile bond strength after six months of storage in normal saline and thereafter for SEM analysis for failure mode, and the 3rd sub-group with one teeth which is prepared for analyzing the bond interface using SEM Results: Summarized data was presented using Tables. Data was normally distributed as tested using the Shaperio‑Wilk W test (p-value was less than 0.05). Therefore, analysis was performed using the parametric tests i.e. Independentt test (for comparing two groups) and One way Anova test (for comparing more than two groups). Level of statistical significance was set at p-value less than 0.05. Conclusion:The lowest bond strength values both at 24 hours and after 6 months in normal saline due to its solvent system (acetone, ethanol, water), which might not create a stable adhesive layer like other agents. Optimal filler load could also reduce bond strength by limiting resin availability. SEM analysis revealed that fewer resin tags, indicating incomplete penetration into dentinal tubules, resulting in weaker bonding and susceptibility to degradation. Adhesive failures indicating poor adhesion at the dentin interface, while mixed failures suggested inadequate bonding with the composite resin. This underscores the importance of refining bonding agent formulations and application techniques to ensure enduring adhesive bonds in restorative dentistry.

The dental technician as a member of the hypodontia multidisciplinary team, with practical considerations for anterior restoration design

Most patients seeking treatment for hypodontia will require prosthetic replacement of their missing teeth. This will be in the form of dentures, bridges and implant restorations. As these are created by one or more dental technicians who supports the clinical team, a close working relationship between these colleagues is likely to improve the quality of treatment outcome. This interaction will usually occur towards the end of the patient's treatment process, when definitive restorations are prescribed. However, appropriately trained and experienced dental technicians should be involved throughout the patient's treatment process as an integral part of the multidisciplinary team approach to effectively manage these patients.This paper describes the contribution of dental technicians to patient care with particular focus on communication between the restorative dentistry clinical team and the dental technician to improve the quality of anterior restorations. As missing maxillary lateral incisor teeth are a common presentation for this patient group, further technical detail relating to planning resin-bonded bridges for replacement of these teeth is included.

Ultrathin lithium disilicate and translucent zirconia crowns for posterior teeth: Survival and failure modes.

To evaluate the reliability and failure modes of ultrathin (0.5 mm) lithium disilicate, translucent and ultra-translucent zirconia crowns for posterior teeth restorations. Fifty-four mandibular first molar crowns of three ceramic materials: (1) Lithium disilicate (e.max CAD, Ivoclar Vivadent), (2) 3Y-TZP (Zirconn Translucent, Vipi), and (3) 5Y-PSZ (Cercon XT, Dentsply Sirona), with 0.5 mm of thickness were milled and cemented onto composite resin abutments. Eighteen samples of each group were tested under mouth-motion step-stress accelerated life testing in a humid environment using mild, moderate, and aggressive profiles. Data was subjected to Weibull statistics. Use level curves were plotted and reliability was calculated for a given mission of 100,000 cycles at 100, 200, and 300 N. Fractographic analyses of representative samples were performed in scanning electron microscope. Beta (β) values suggest that failures were dictated by material's strength for lithium disilicate and by fatigue damage accumulation for both zirconias. No significant differences were detected in Weibull modulus and characteristic strength among groups. At a given mission of 100,000 cycles at 100 N, lithium disilicate presented higher reliability (98% CB: 95-99) regarding 3Y-TZP and 5Y-PSZ groups (84% CB: 65%-93% and 79% CB: 37&-94%, respectively). At 200 N, lithium disilicate reliability (82% CB: 66%-91%) was higher than 5Y-PSZ (20% CB: 4%-44%) and not significantly different from 3Y-TZP (54% CB: 32%-72%). Furthermore, at 300 N no significant differences in reliability were detected among groups, with a notable reduction in the reliability of all materials. Fractographic analyses showed that crack initiated at the interface between the composite core and the ceramic crowns due to tensile stress generated at the intaglio surface. Ultrathin lithium disilicate crowns demonstrated higher reliability relative to zirconia crowns at functional loads. Lithium disilicate and zirconia crown's reliability decreased significantly for missions at higher loads and similar failure modes were observed regardless of crown material. The indication of 0.5 mm thickness crowns in high-load bearing regions must be carefully evaluated. Ultraconservative lithium disilicate and zirconia crowns of 0.5 mm thickness may be indicated in anterior restorations and pre-molars. Their clinical indication in high-load requirement regions must be carefully evaluated.

Clinical performance of immediately placed and immediately loaded single implants in the esthetic zone: A systematic review and meta-analysis.

The aim of this study was to assess the following PIO question: In adult patients treated with an indication for single tooth extraction in the maxillary esthetic zone (15-25), what is the influence of an immediate implant placement and immediate loading protocol on the clinical performance (primary aim) and esthetic outcomes (secondary aim) focusing on investigations published after 2010. An electronic search in Medline (PubMed), the Cochrane Central Register of Controlled Trials, and EMBASE databases up to April 2022 was performed to identify clinical studies investigating the outcome of single implants subjected to immediate placement with immediate restoration/loading (Type 1A). Sixty-three studies (10 randomized controlled trials, 28 prospective and 25 retrospective cohort studies) were included with a follow-up ranging from 12 to 96 months. One thousand nine hundred sixty-one implants reported survival rates of 99.2 (98.6-99.5) % at 1 year, 97.5 (95.9-98.4) % after 3 years, and 95.8 (93.3-97.4) % after 5 years; 1064 immediately loaded restorations presented survival rates of 98.9 (97.8-99.5) % after 1 year, 96.8 (93.6-98.4) % after 2 years, and 94.8 (89.6-97.4) % after 5 years. Comparing baseline to 12-month data using the Hedges' g effect size (95% CI), papilla height presented an overall effect size of -0.71 (-1.25, -0.1) mm, midfacial recession change of -0.15 (-0.66, 0.36) mm, and a 0.82 (0.37, 1.28) gain in PES. Immediate implant placement and immediate loading can be considered a predictable and safe treatment option for single maxillary anterior restorations with adequate survival rates and favorable esthetics outcomes for up to 5 years.

Biomechanical performance of endocrown and core-crown restorations: A systematic review.

To assess and compare, through a systematic review of the literature, the biomechanical performance of endocrowns and traditional core-crowns (with and without intracanal post) for the rehabilitation of endodontically treated teeth with severe coronal structure damage. A systematic search was performed in MEDLINE/PubMed, Scopus, and Web of Science databases. In-vitro studies comparing endocrowns with (post-)core-crown restorations were selected and screened by two independent reviewers. The included studies were submitted to the risk of bias analysis using the RoBDEMAT tool and the biomechanical outcomes were collected for qualitative analysis. The extracted data were presented based on comparative analyses among the included studies. Thirty-one studies were included: 9 studies evaluated restorations of molars, 14 for premolars, and 8 studies evaluated anterior restorations. For the majority of the studies, endocrowns showed either similar or greater survival rates under fatigue and monotonic load than (post-)core-crown restorations, irrespectively of the tooth. The endocrowns showed more favorable failure patterns than (post-)core-crowns, irrespectively of the tooth. Endocrowns produced lower stresses in the restorative material for molars and premolars and in the luting material for premolars than (post-)core-crown restorations. The included studies presented adequate information for most items of the RoBDEMAT risk of bias tool. Endocrowns showed similar or greater biomechanical performance than the traditional (post-)core-crown restorations in most of the evaluated studies. This systematic review showed that endocrowns present either similar or greater biomechanical performance than core-crown restorations for anterior and posterior endodontically treated teeth with severe structural damage.

Awareness of Golden Proportion in Tooth Forms Among Dental Scholars in Saudi Arabia: A Cross-Sectional Study.

Background There are numerous uses ofgolden proportion (GoP) in dentistry, particularly cosmetic dentistry. The research on GoP has been lacking, particularly the knowledge of GoP among dentistry students still enrolled in classes and those undergoing training. Therefore, this study primarily aimed to determine how knowledgeable dental scholars (dentist scholars are final-year undergraduates, interns, Ph.D. scholars, and postgraduate students) in Saudi Arabia were of GoP in tooth forms. Methodology A total of 500 scholars who met the requisite criteria were considered eligible for this study and were provided with a questionnaire that consisted of background questions and 16 close-ended questions related to GoP. The data was analyzed, and descriptive and inferential statistics were used, with a P-value ≤ 0.05 at a 95% confidence interval (CI) deemed statistically significant. Results It was observed that most respondents believed that a smile was important for a patient. The results also indicated that most respondents had heard of GoP for smile designing, indicating that it is a well-known concept among dental scholarsin Saudi Arabia. The findings also revealed that most respondents believed that the GoP ratio is 1.618 and that it is important as a guide to anterior restoration. Conclusions Most respondents considered the smile important and the golden ratio to be present in many fields, but their understanding of the concept varied. However, the study had some limitations, including the potential bias in self-reported responses and a lack of clinical application of the GoP. Future studies could investigate the practical implications ofGoP in aesthetic dentistry and the effect of demographic factors on awareness and understanding of the concept.

The 3D emergence profile on implant-supported restorations: A method for evaluating restorative angles.

Emerging evidence indicates that the emergence profile and subsequent restorative angle play a crucial role in clinical outcomes and can potentially affect the development and progression of peri-implant diseases. However, the traditional evaluation of the emergence profile and angle has been limited to mesial and distal sites using periapical x-rays, without considering the buccal sites. To describe a novel 3D method to estimate the emergence profile and restorative angles around single implant-supported crowns including buccal sites. A total of 30 implant-supported crowns (11 molars, 8 premolars, 8 central incisors and 1 canine) were extra-orally scanned using an intraoral scanner and the STL files produced were imported into a 3D software. The crown/abutment interface of each crown was delineated, and apico-coronal lines were automatically drawn following the shape of the crown. Three reference points were defined on the apico-coronal lines at the transition edge of the biological (BC) and the esthetic zone (EC) and the resulting angles were then calculated. The reliability of the measurements (2D and 3D) were assessed using the intraclass correlation coefficient (ICC). In anterior restorations, the mean angle of the esthetic zone amounted to 162 ± 14° at mesial sites, to 140 ± 10° at buccal sites and to 163 ± 11° at distal sites. The corresponding angles at the biological zones, amounted to 155 ± 13° at mesial sites, 139 ± 15° at buccal sites and 157 ± 5° at distal sites. In posterior restorations, the mean angle of the esthetic zone amounted to 162 ± 12° at mesial sites, to 157 ± 13 at buccal sites and to 162 ± 11 at distal sites. The corresponding angles at the biological zone, amounted to 158 ± 8 at mesial sites, 150 ± 15° at buccal sites and 156 ± 10 at distal sites. The ICC for all measurements ranged between 0.77 and 0.99 indicating a good intra-examiner reliability. Within the limitations of the present study, the 3D analysis seems to be a reliable and applicable method for the quantitative evaluation of the emergence profile in daily practice. Future randomized clinical trials are needed to assess whether a 3D analysis with the ensuing the emergence profile serves as a predictor for clinical outcomes. The development and implementation of a 3D workflow will provide technicians and dentists with the ability to assess the restorative angle of implant-supported restorations during the provisional phase and the final restoration. This approach may help achieve an aesthetically pleasing restoration while minimizing potential clinical complications.

The Effect of Chemical Degradation and Polishing on the Gloss of Composite Dental Materials.

This aim of this study was to investigate surface gloss changes of different composite dental materials after chemical degradation or polishing. Five different composites were used (Evetric, GrandioSO, Admira Fusion, Filtek Z550, Dynamic Plus). The gloss of the tested material was measured with a glossmeter before and after chemical degradation in different acidic beverages. Statistical analysis was performed using a t-test for dependent samples, ANOVA, and a post hoc test. For comparison between groups, a level of significance was set at 0.05. Initial gloss values ranged from 51 to 93 at baseline to 32 to 81 after chemical degradation. The highest values were obtained for Dynamic Plus (93.5 GU) and GrandioSO (77.8 GU), followed by Admira Fusion (82 GU) and Filtek Z550 (70.5 GU). Evetric showed the lowest initial gloss values. After acidic exposures, the gloss measurements revealed different patterns of surface degradation. The results showed that the gloss of the samples decreased with time regardless of the treatment. The interaction between chemical-erosive beverages and the composite could lead to a decrease in the surface gloss of the composite restoration. The nanohybrid composite showed less gloss changes under acidic conditions, suggesting that it is more suitable for anterior restorations.

Indirect Anterior Restorations with no-prep technique: Aesthetic and Biological Effectiveness

AbstractThe aesthetic result in the ceramic restoration of anterior teeth has always been a challenge in clinical practice and, in these cases, success depends on the skills of both the clinician and the dental technician. In current dentistry, the main objective is to pursue aesthetic results while preserving biological structures. Among the various conservative techniques available for anterior restorations, veneers are the most advantageous, compared to traditional crown preparation, both for the amount of tooth structure preserved in the preparation phase and for the direct adhesion on the enamel in the cementation. This article presents a clinical case of no-prep porcelain veneers (no-prep technique) for smile frame restoration.

A Three-step Etch-and-Rinse vs a Universal Adhesive in Nanohybrid Composite Anterior Restorations: A Retrospective Clinical Evaluation.

To retrospectively evaluate the clinical behavior of direct anterior composite restorations performed with a universal adhesive or with a three-step etch-and-rinse (E&R) adhesive. Patients were randomly treated with a three-step E&R adhesive (Optibond FL, Kerr) or a universal adhesive (Clearfil Universal Bond Quick, Kuraray Noritake) applied in E&R mode. All restorations were performed with a nanohybrid composite (ClearFil Majesty ES-2, Kuraray Noritake) by the same experienced operator. Two calibrated examiners evaluated the restorations using a dental mirror and explorer, in accordance with modified United States Public Health Service (USPHS) procedures. Clinical events were registered and classified as either failure (F), survival (SR), or success (S). 168 restorations were evaluated in 90 patients with an average follow-up period of 37.9 (± 22.9) months. A total of 132 restorations were performed on vital teeth, and 36 were performed on endodontically treated teeth (ETT). A total of 128 Class-IV and 40 Class-III restorations were performed. In 89 restorations, a three-step E&R adhesive was applied (14 Class-III and 75 Class-IV), while in 79, a universal adhesive was used (26 Class-III and 53 Class-IV, p = 0.0091). A Cox regression analysis was performed (p < 0.05) to analyze which factors were involved in the failure of the restorations, considering failure (F) as restorations that needed re-intervention at the follow-up period of 37.9 (± 22.9) months. No statistically significant differences were observed when considering parameters directly involved with the adhesives tested. Endodontically treated teeth were more prone to fractures (p = 0.0006) compared to vital teeth. Restorations made with universal adhesives failed by fracturing significantly more frequently (p = 0.0234), while restorations made on endodontically treated teeth had a significantly worse outcome (p = 0.0001). Restorations made on canines also failed significantly more frequently (HR = 3.8, 95% CI = 1.4-10.1, p = 0.0062). Based on the obtained results, both the universal adhesive and the three-step E&R adhesive proved to be good treatment choices for direct anterior restorations after 37.9 (± 22.9) months of follow-up. Tooth vitality seems fundamental for the prognosis of a direct anterior composite restoration over time.

The Aesthetic Restoration of Missing Anterior Teeth with A Dmls Prosthesis-A Case Report

The most significant social connecting gesture and vital to professional advancement is a confident, appealing smile. Patients may experience social and psychological discomfort as a result of the loss of their anterior teeth. The contemporary dental situation provides numerous treatment options for the aesthetic and functional replacement of a congenitally or traumatically lost anterior tooth in young and adult patients, including implant crown, conventional FDP, Resin Bonded FDP, or RPD. The most important aspect of an aesthetic anterior restoration is patient satisfaction with the cosmetic and functional outcome of therapy. This case report discusses the aesthetic correction of missing maxillary and mandibular anterior teeth using intra-oral scanning and DMLS PFM crowns.

Influence of toothbrush abrasion on the surface characteristics of CAD/CAM composite resin blocks with shade gradations.

Crown restorations in anterior region are recommended highly color-reproductivity because of aesthetic reason. Composite resin block with several shade gradations is especially produced for anterior restorations. To clarify the durability of an aesthetic, the effect of toothbrush abrasion on surface properties was performed. Composite-resin blocks without shade gradation and a ceramic block were used as controls. All specimens were prepared using #2000 SiC paper and polished using an aluminum oxide polishing paste. Toothbrush abrasion tests were carried out for 20,000 cycles at a frequency of 2 Hz with 2.0 N load. Gloss and surface roughness were measured before and after toothbrush abrasion. The number of repetitions was set to five. It was clarified that tooth brushing caused to decrease in the gloss and to increase in the surface roughness with significant negative correlations between these results not only in composite-resin blocks without shade gradation but also in those with gradation.

Fit of anterior restorations made of 3D-printed and milled zirconia: An in-vitro study

ObjectivesTo evaluate the fit of zirconia veneers made by either 3D printing or milling. MethodsA typodont maxillary central incisor was prepared for a 0.5-mm-thick veneer and was reproduced 36 times from resin. Restorations were designed with a 20-µm-wide marginal and a 60-µm-wide internal cement gap, and were made from 3D-printed zirconia (LithaCon 3Y 210, Lithoz, n = 24) and milled zirconia (Cercon ht, DentsplySirona, n = 12). For milled zirconia, a drill compensation was needed to give the milling bur access to the intaglio surface. The restorations were cemented, cross-sectioned, and the cement gap size was analyzed by two raters. Inter-rater reliability was studied at 12 3D-printed veneers (intraclass correlation coefficient, ICC, mixed model, absolute agreement). Twelve remaining 3D-printed restorations were compared with 12 milled restorations regarding fit at three locations: marginally, labially, and at the incisal edge (Mann–Whitney U-tests, α<0.05). ResultsInter-rater reliability was excellent, with an ICC single-measure coefficient of 0.944 (95%-confidence interval: [0.907; 0.966]). Gap sizes (mean ± SD / maximum) were 55 ± 9 / 143 µm at the margins, 68 ± 14 / 130 µm labially, and 78 ± 19 / 176 µm at the incisor edge for 3D-printed veneers. For milled veneers, gap sizes were 44 ± 11 / 141 µm at the margins, 85 ± 19 / 171 µm labially, and 391 ± 26 / 477 µm at the incisor edge. At the margins, the milled veneers outperformed the 3D-printed restorations (p = 0.011). The cement gap at the incisor edge was significantly smaller after 3D printing (p < 0.001). Conclusions3D-printed zirconia restorations showed clinically acceptable mean marginal gaps below 100 µm. Because drill compensation could be omitted with 3D printing, the fit at the sharp incisal edge was significantly tighter than with milling. Clinical significanceThe fit of 3D-printed ceramic anterior restorations meets clinical standards. In addition, 3D printing is associated with a greater geometrical freedom than milling. With regard to fit this feature allows tighter adaptation even after minimally invasive preparation.

Marginal Discrepancy of Five Contemporary Dental Ceramics for Anterior Restorations.

This study aimed to compare marginal accuracy of five contemporary all-ceramic crowns indicated for anterior restorations. A master die of maxillary central incisor was prepared for all-ceramic crown and duplicated to produce 50 replicas of epoxy resin material. Five ceramic materials were used to mill the crowns (n = 10). All crowns were manufactured following the same digital workflow; same master die, scanning unit and design software, and the recommended manufacturing protocol. Final seating of crown was secured by a small droplet of temporary cement on its incisal edge. Marginal accuracy was evaluated by scanning electronic microscope with a magnification of 300 × . Vertical marginal gap was measured for each crown at predefined four points. One-way analysis of variance was used to test differences between groups and Tukey test was used for multiple comparisons between group combinations. A level of significance at 95% was set for all statistics. The highest mean marginal gap and mean maximum gap calculated were for the e.max CAD crowns (49.2 µm, 87.6 µm), while the lowest values were for the Cercon xt crowns (10.2 µm, 21.7 µm). The mean marginal gap and the mean maximum gap of the e.max CAD crowns were statistically significantly greater than those of all other groups (p < 0.05). However, the differences between all other combinations were insignificant (p > 0.05). Marginal accuracy of lithium disilicate crowns is clinically acceptable. Zirconia and zirconia-reinforced lithium silicate materials can produce a greater level of marginal accuracy compared to lithium disilicate.

Measurement and analysis of maxillary anterior teeth color in the chinese population.

To measure the difference in the crown color of the maxillary anterior teeth in the Chinese population, to study its potential regularity, and to provide a reference for the colorimetry of oral anterior teeth restoration. Using VITA Easyshade Advance4.0 spectrophotometer (the colorimetric system is CIE-1976-L*a*b*), adult patients who were treated in Sanming Integrated Medicine Hospital, Fujian Province, China, from January 2022 to June 2022 160 patients (88 males, 72 females, aged 20-60 years) were used as the survey subjects, and the L*a*b* of 1/3 of the crowns of 6 anterior teeth (central incisors, lateral incisors, canines) were measured Value, statistical analysis was performed with SPSS 26.0 software. The mean L* values of maxillary central incisors, lateral incisors, and canines in the Chinese population were: (73.02±4.41), (69.96±4.70), (65.14±4.21); the mean a* values were: (-0.54±4.21) 0.35), (0.22±0.63), (1.40±0.62), and the mean values of b* were: (14.50±3.23), (18.60±3.94), (23.64±3.30). 1. There was no significant difference in L*a*b* value between left and right symmetrical teeth with the same name (P>0.05). 2. There was no statistical difference in the L*a*b* value between genders (P>0.05), 3. There was a statistical difference in L*a*b* value between different tooth positions (P< 0.05). 4. There were significant differences in L*a*b* values in different age groups (P< 0.05). 1. The color of the labial crown of maxillary anterior teeth in the Chinese population is related to different age groups and tooth positions but not gender. 2. In the Chinese population, the color of the maxillary anterior teeth on the labial side gradually decreased from the central incisor to the distal end of the dental arch while the chroma gradually increased. 3. With age increase, the L* and a* values of the upper central incisors, upper lateral incisors, and upper canines gradually decrease, and the b* value gradually increases. The teeth became darker, more yellow, and redder. 4. In the clinical colorimetry of the upper anterior teeth, the contralateral tooth with the same name is preferred. Suppose the tooth with the same name is missing at the same time. In that case, when using the adjacent teeth as a reference, the different brightness and chroma between the central incisors, lateral incisors, and canine teeth should be compared. Change trend to determine. 5. A uniform tooth color should not be selected for anterior restoration, and age should be considered when choosing a color for the patient. Key words:Upper anterior teeth, Crown color, CIE-1976-L*a*b*, spectrophotometric colorimeter.

An In Vitro Comparative Evaluation of Fracture Strength of Composite Resin and Activa Kids Bioactive Restorative for Use in Strip Crowns

Background Advanced stages of early childhood caries requires complex measures such as strip crowns for the anterior teeth and stainless steel crowns for the posterior teeth. Composite resin is the traditional material of choice for use in strip crowns. ACTIVA KIDS Bio ACTIVE-RESTORATIVE is the first bioactive composite with pedo shade delivering all the chemical properties of glass-ionomer cement and physical properties of composite resins.Aim The aim of this study was to compare the fracture strengths of composite resin and ACTIVA KIDS BioActive Restorative Pulpdent USA when used with a strip crown for restoring primary anterior teeth.Methodology Twenty exfoliated non-carious human maxillary primary central and lateral incisors were selected for the study to receive strip crowns and the dimensions were standardized for all the samples. In Group I Composite resin Te-Encom Plus Ivoclar vivadent and in Group II ACTIVA Kids BioActive Restorative Pulpdent USA were used to fill the strip crowns respectively after etching and application of bonding agent. After light curing the samples strip crowns were then removed assessed for fracture strength under Universal testing machine. Fracture strength of both the groups was statistically analyzed and recorded using student ldquotrdquo test.Results The minimum to maximum force obtained was 235.08ndash682.71 N for Group 1 which when compared to Group II 167.57ndash449.29 N was higher. However fracture strength between both the groups p .062 showed no significant difference statistically. Deformation at break percentage has shown significant difference between both the groups p.004 which was higher for Group I 1.34 when compared to Group II 0.68.Conclusion The fracture strength of experimental group restored with ACTIVA Kids Bioactive Restorative was comparable with composite resin when used as a core material inside the strip crown for anterior restorations. ACTIVA Kids Bioactive Restorative can be a better material of choice compared to traditional composite resins because of its excellent chemical and physical properties. The data also showed the fracture strength of ACTIVA Kids Bioactive Restorative to be comparable to composite resins.

Comparison between color stability of zirconia and lithium disilicate

The most widely used glass-ceramic is lithium disilicate (LD) because of its remarkable optical qualities, high strength, and simplicity of manufacture. Greater marginal strength, reduced porosity, and net-shaped manufacturing by pressing are further benefits of LD. The development of yttrium stabilized trigonal zirconia polycrystalline (Y-TZP) ceramics is the result of the pursuit for a material with both mechanical capabilities, like the resistance provided by metallic restoration, and the distinctive optical characteristics of glass-ceramic. The main drawback is the fragile veneering ceramics, which are prone to chipping, debonding, and breakage. There is evidence that extrinsic variables such beverages, mouthwashes, acid solutions, dental brushing, and increased temperatures might cause ceramic surfaces to deteriorate. The composition and surface shape of ceramic materials have an impact on the extrinsic pigment absorption or adsorption from the oral cavity. The main causes for the clinical replacement of anterior restorations, according to prior research, are poor color matching and color instabilities. Monolithic zirconia is more prone to staining from chlorhexidine, green tea, and coffee. In monolithic zirconia, the aging-related color changes are more pronounced. The color of the background substructure influences how zirconia restorations look overall. In terms of color stability and translucency, LD ceramic has also been proven to be more aesthetically pleasing. In comparison to monolithic zirconia, bilayer zirconia with feldspar veneering ceramic displayed reduced discoloration overall. It has been noted that monolithic zirconia is more susceptible to low-temperature degradation than the core Y-TZP. The use of current literature to infer outcomes has several limitations because in most vitro investigations, thermocycling has been carried out in water rather than oral cavity saliva and the influence of sunlight exposure, salivary proteins, food coloring, tobacco, different enzymes, and surface-related factors on the color stability is yet to be examined.