Single crowns versus conventional fillings for the restoration of root filled teeth

Treatment Prognosis of Restored Teeth with Crown Lengthening vs. Deep Margin Elevation: A Systematic Review

Crown lengthening surgery and deep margin elevation are two distinct approaches used to manage decayed teeth. This systematic review examined the survival rate of badly decayed teeth when restored using the crown lengthening technique and compared it to the deep margin elevation technique. The search was conducted during July 2020 and then again updated at the end of July 2021, and no restriction concerning publication status and time was applied during the search. Cochrane Database, EBSCO, Scopus, and Medline databases were searched electronically for relevant literature. Google Scholar was used as a secondary source. Predefined inclusion and exclusion criteria were used to select the relevant articles. PRISMA guidelines were followed. The focused PICO question was: 'Does the crown lengthening technique (I) provide a better survival rate (O) than deep margin elevation technique (C) following the restoration of badly decayed teeth (P).' A total of six articles were included after performing screening based on the eligibility criteria. Four studies focused on crown lengthening while two focused on deep margin elevation technique. A majority of the studies showed a high risk of bias owing to methodological insufficiencies. Crown lengthening (CL) treated cases showed a change in the free gingival margin at six months post-surgery. A tissue rebound was seen that was correlated to the periodontal biotype. Teeth treated with the deep margin elevation (DME) technique showed high survivability. There is a lack of high-quality trials examining surgical comparisons between CL and DME with long-term follow-up. Patient- and dentist-reported outcomes have not been given adequate consideration in the literature. Based on the limited evidence, it can be concluded that for restorative purposes, crown lengthening surgery can be successful in long-term retention of restored teeth. However, the deep margin elevation technique has a better survival ratio. Future well-designed and executed research will have an effect on the evidence and level of certainty for the best approach to treating severely decayed teeth.

Fracture resistance of endodontically-treated maxillary premolars restored with different type of posts and direct composite reconstructions: A systematic review and meta-analysis of in vitro studies

OBJECTIVE

To conduct a systematic review and meta-analysis to assess if the presence of an endodontic post may increase the fracture resistance of endodontically-treated maxillary premolars directly restored with composite.

METHODS

A comprehensive systematic literature search according to the PRISMA statement was conducted to assess in vitro studies including endodontically-treated maxillary premolars, restored with different type of posts supporting direct composite reconstructions. Two groups of meta-analyses were performed using fixed effects model and additional Trial Sequential Analysis (TSA) was carried out. Moreover, risk of bias was conducted and quality of evidence for any performed meta-analysis was assessed using Grading of Recommendations Assessment, Development and Evaluation (GRADE).

RESULTS

Twenty-four articles met the inclusion criteria and 13 studies also underwent quantitative evaluation. Fracture resistance of endodontically-treated premolars restored with fiber posts was significantly less than sound teeth (p value: < 0.00001), however endodontically-treated premolars with a fiber post provided an increase in fracture resistance when compared to equivalent teeth restored without post (p value: 0.003). TSA revealed high power of both meta-analyses. Moderate risk of bias was reported in 23/24 studies; only 1 study showed high risk of bias. GRADE system showed moderate strength of evidence due to the presence of a study with high risk of bias and to wide confidence intervals.

SIGNIFICANCE

Within the limitation of the present systematic review and meta-analysis, it can be concluded that endodontically-treated maxillary premolars restored with a fiber post and direct composite restoration demonstrated increased fracture resistance when compared to equivalent teeth without post.

Radiological Evaluation of Stainless Steel Crowns Placed on Permanent Teeth in Patients Treated under General Anaesthesia

Evidence-based evaluations of dental treatment are needed to support the development of special care dentistry services. This retrospective study was designed to collect and analyse X-ray images of permanent teeth restored with stainless steel crowns (SSC) in patients treated under general anaesthesia. Between 2013 and 2019, 360 permanent molars were crowned with SSCs in 198 adult patients. One calibrated investigator used an original validated tool to evaluate four radiographic criteria for molars restored with SSCs: (i) marginal adaptation; (ii) interdental proximal contact; (iii) the presence of glass ionomer cement overflow; and (iv) the loss of alveolar bone. Overall, no defect or a minor defect was reported for the majority of SSCs for the criteria “Marginal adaptation” (62.5%, n = 320), “Proximal contact” (82.2%, n = 236) and “Cement overflow” (95.8%, n = 337). Alveolar bone resorption was reported in 8.3% of cases, n = 14, after a mean period of 8.9 ± 14.3 months. It was shown that the restoration of permanent teeth using SSCs placed under general anaesthesia presents a low risk of periodontal morbidity in the medium term when assessed radiographically.

Therapeutic Functions of Stem Cells from Oral Cavity: An Update

Adult stem cells have been developed as therapeutics for tissue regeneration and immune regulation due to their self-renewing, differentiating, and paracrine functions. Recently, a variety of adult stem cells from the oral cavity have been discovered, and these dental stem cells mostly exhibit the characteristics of mesenchymal stem cells (MSCs). Dental MSCs can be applied for the replacement of dental and oral tissues against various tissue-damaging conditions including dental caries, periodontitis, and oral cancers, as well as for systemic regulation of excessive inflammation in immune disorders, such as autoimmune diseases and hypersensitivity. Therefore, in this review, we summarized and updated the types of dental stem cells and their functions to exert therapeutic efficacy against diseases.

Survival Rates of Endodontically Treated Teeth After Placement of Definitive Coronal Restoration: 8-Year Retrospective Study

Introduction

Preservation of endodontically treated teeth (ETT) depends upon several patient-related and operator-related factors. The objectives of this study were to assess the effects of different types of coronal restoration and delayed placement on ETT survival.

Methods

Data on dates of root canal treatment (RCT), restoration type, and extraction time of tooth, when applicable, were analyzed for all patients who underwent RCT from 2010 to 2018 at our institution.

Inclusion Criteria

Root canal-treated teeth with complete preoperative and postoperative radiographs; ETT that were restorable and received final permanent coronal restorations; no periodontal disease or crack detected during RCT; and ETT with acceptable RCT quality.

Exclusion Criteria

Patients who did not attend for follow-up, those had incomplete information available about the coronal restoration, and those with periodontally compromised teeth were excluded. ETT that involved any procedural error were also excluded. The teeth were categorized according to whether they underwent definitive coronal restoration 0–14 days, 15–59 days, or 60+ days after RCT. The statistical analysis was performed using SPSS version 25 (IBM Corp., Armonk, NY). The rate of survival of ETT of 8 years was estimated, and the differences between groups were determined after applying Kaplan–Meier statistics and log-rank tests. A multivariate Cox regression test and Wilcoxon (Gehan) statistics were computed to analyze the influence of different variables. A P-value <0.05 was considered as statistically significant.

Results

The type of restoration, opposing dentition, presence of a post, and dentistry training (year 4 or 5 students) showed significant effects on the survival of ETT (P ≤ 0.000). ETT which received crowns was 2.05 times more likely to need extraction than those in which a composite buildup was performed (hazard ratio [HR] 2.05; confidence interval [CI] 1.84–2.29; P ≤ 0.000). All composite buildups were performed within 14 days of completion of RCT. There was a significant correlation between the time of placement of the final coronal restoration and ETT survival (P ≤ 0.000). Extraction of ETT was 25% more likely (HR 0.25; CI 0.231–0.277) when the final coronal restoration was placed 15–59 days after completion of RCT and 73% more likely (HR 0.73; CI 0.655–0.814) when placed after 60 days than when placed at 0–14 days.

Conclusion

Timely placement of the final coronal restoration is found to be the most critical factor affecting the long-term survival of teeth after RCT.

Effect of Smart Dentin Replacement, Biodentine, and Its Combination for Dentin Replacement as Alternatives to Full-crown Coverage for Endodontically Treated Molars: An In Vitro Study

Aim:

The aim of this in vitro study was to assess newer dentin replacement restorative materials that could substitute full-crown coverage restoration.

Materials and Methods:

Twenty freshly extracted maxillary and mandibular molars were selected for this in vitro study and were randomly divided into four groups of five teeth each. All the teeth in the experimental groups (Groups 2–4) were subjected to access cavity preparation, mimicking class 1 deep dentinal caries without involving marginal ridges, and with approximately 1.5 mm of tooth structure remaining throughout its circumference. Group 1: sound molar teeth, which will serve as a control group. Group 2: endodontically treated molars restored with smart dentin replacement (SDR) as post-endodontic restoration. Group 3: endodontically treated molars restored with Biodentine as post-endodontic restoration. Group 4: endodontically treated molars restored with the combination of SDR and Biodentine as the post-endodontic restoration. Fracture resistance of all the teeth was then evaluated using a universal testing machine.

Statistical Analysis:

The results of this in vitro study were calculated statistically using one-way analysis of variance and post hoc tests such as Tukey’s, Scheffe’s, Bonferroni, and Holm tests for intragroup comparison.

Results:

Statistically significant results were observed among all groups, except Group 2 (SDR) and Group 4 (combination of SDR and Biodentine). The highest and lowest values were noted with Groups 2 and 3, respectively, (P = 0.05).

Conclusion:

SDR alone or the combination of SDR with Biodentine can be considered as a substitute for full-crown coverage restoration for endodontically treated molars.

Dentists' decisions regarding the need for cuspal coverage for endodontically treated and vital posterior teeth

Objectives

Deciding when cuspal coverage is needed for posterior teeth is considered a challenge for dentists. The aims were to assess dentists' decision making regarding the need for cuspal coverage for vital teeth (VT) and endodontically treated teeth (ETT) with varying amounts of tooth structure loss and to identify clinical situations of dissimilarity and uncertainty in decision making.

Materials and Methods

A random sample of 182 dentists were invited to participate in the survey. The survey included photos of 13 posterior teeth: six VT and seven ETT. The clinical situations selected were based on a hypothetical scale of typodont teeth with ascending amounts of tooth structure loss. A brief description of each situation was provided. Each dentist was asked to decide whether cuspal coverage is needed, not needed, or unsure. Descriptive analyses using SPSS were conducted. Seventy-five percent was chosen as a cutoff point for assessing similarity in decision making. The unsure answer reflected uncertainty. Associations were assessed using chi-square test.

Results

One hundred twenty dentists participated (65.9% response rate, 70 females). Median for years of experience was 3.5 (interquartile range 1.1-10.8). Analyses revealed a similarity percentage of <75% in decision making among dentists for six clinical situations: four VT and two ETT. More similarity was observed for situations at both ends of the scale with minimal and severe amounts of tooth structure loss and more for ETT than for VT. The highest percentages of uncertainty were more for VT than for ETT. Clinical conditions of VT were more likely to receive the "not sure" decision compared with those of ETT (χ2, P < .001). No association was detected with gender (χ2, P = .509) or years of experience (χ2, P = .223).

Conclusions

Dissimilarity and uncertainty in deciding when cuspal coverage is needed were observed especially for VT and teeth with a moderate amount of structure loss.

Clinical and histological reaction of periodontal tissues to subgingival resin composite restorations

OBJECTIVES

To compare the clinical and histological response of supracrestal periodontal tissues to subgingival composite restorations versus natural root surfaces MATERIAL AND METHODS: In 29 subjects with a single tooth requiring subgingival restorations, a deep margin elevation (DME) procedure with composite resin was applied. Full-mouth plaque score (FMPS), full-mouth bleeding score (FMBS), and focal probing depth (PD) were measured at baseline, before DME, and after 3 months. The distance between the coronal marked (CM) point to the apical margin of the composite reconstruction (AMR), at baseline, and to the tip of the periodontal probe inserted to reach the bottom of the sulcus (APP), 3 months later, was measured. An all-around secondary flap, harvested to ensure the subsequent single-crown prosthetic rehabilitation was histologically processed. The histological inflammation degree was evaluated in areas of gingival tissues adjacent to the composite (group B) and adjacent to the natural surface of each single tooth (group A).

RESULTS

Significant FMPS, FMBS, and PD decreases were observed (p < 0.05). CM-AMR and CM-APP were significantly different (p < 0.05), suggesting an attachment gain after 3-months. The inflammation level of gingival tissue was similar in groups A and B (p > 0.05).

CONCLUSIONS

For the first time, this topic was clinically and histologically studied in humans. Subgingival restorations resulted compatible with gingival health, with levels similar to that of untreated root surfaces.

CLINICAL RELEVANCE

Deep margin elevation procedure produces favorable clinical and histological outcomes allowing a routine utilization in reconstructive dentistry.

IPS e.max for All-Ceramic Restorations: Clinical Survival and Success Rates of Full-Coverage Crowns and Fixed Partial Dentures

The IPS e.max system by Ivoclar Vivadent, offering a variety of products and indications, is widely used for all-ceramic restorations. We analyzed the clinical track record of these products in daily clinical practice, associating their restorative survival rate with various parameters to define recommendations for long-term stability. A total of 1058 full-coverage crowns and fixed partial dentures (FPDs) were evaluated retrospectively over up to 66.48 (37.05 ± 18.4) months. All were made of IPS e.max Press, IPS e.max CAD, IPS e.max Ceram or IPS e.max ZirPress and had been delivered by a private dental practice within three years. Uses not recommended by the manufacturer were also deliberately included. The five-year cumulative survival was 94.22% (i.e., 94.69% or 90.58% for glass-ceramic crowns or FDPs and 100% or 90.06% for zirconia-based crowns or FDPs). Significantly superior outcomes emerged for conventional vs. adhesive cementation and for vital vs. non-vital abutment teeth, but not for recommended vs. non-recommended uses. Caution is required in restoring non-vital teeth, but the spectrum of recommended uses should generally be reconsidered and expanded, given our finding of high survival and success rates for IPS e.max ceramics, even for uses not currently recommended by the manufacturer.

Fracture Strength of Various Types of Large Direct Composite and Indirect Glass Ceramic Restorations

INTRODUCTION

The objective of this study was to investigate the mechanical behavior of severely compromised endodontically treated molars restored by means of various types of composite buildups, full-contour lithium disilicate crowns (with or without post) or a lithium disilicate endocrown.

METHODS AND MATERIALS

One hundred five sound molars were endodontically treated and randomly assigned to 1 control group (endodontic access cavity only) and 6 experimental groups (n=15): glass fiber reinforced composite (GFRC group), direct microhybrid composite (C group), direct microhybrid composite restoration with glass fiber post (CP group), composite buildup and full-contour lithium disilicate crown (LDS group), additional glass fiber post (P-LDS group), and endocrown (EC group). Molar crowns in the treatment groups were removed 1 mm above the cementoenamel junction and restored. All specimens were thermomechanically aged (1.2×10⁶ cycles at 1.7 Hz/50N, 8000 cycles 5°C to 55°C) and axially loaded until failure. Data were analyzed using analysis of variance and Tukey post hoc test (α=0.05).

RESULTS

Fracture strength was significantly affected by the type of restoration (p=0.000; statistically similar groups identified with superscript letters): LDS^B (3217±1052 N), P-LDS^AB (2697±665 N), EC^AB (2425±993 N), C^A (2192±752), control^A (1890±774 N), CP^A (1830±590 N), and GFRC^A (1823±911 N). Group GFRC obtained significantly more repairable fractures than the other groups.

CONCLUSIONS

Significant differences in fracture strength were obtained between LDS, the composite restorations, and control group. Direct composite restorations showed similar fracture strength as P-LDS and EC. Incorporating a glass fiber reinforced composite resulted in significantly more repairable failures.

Dealing with missing standard deviation and mean values in meta-analysis of continuous outcomes: a systematic review

BACKGROUND

Rigorous, informative meta-analyses rely on availability of appropriate summary statistics or individual participant data. For continuous outcomes, especially those with naturally skewed distributions, summary information on the mean or variability often goes unreported. While full reporting of original trial data is the ideal, we sought to identify methods for handling unreported mean or variability summary statistics in meta-analysis.

METHODS

We undertook two systematic literature reviews to identify methodological approaches used to deal with missing mean or variability summary statistics. Five electronic databases were searched, in addition to the Cochrane Colloquium abstract books and the Cochrane Statistics Methods Group mailing list archive. We also conducted cited reference searching and emailed topic experts to identify recent methodological developments. Details recorded included the description of the method, the information required to implement the method, any underlying assumptions and whether the method could be readily applied in standard statistical software. We provided a summary description of the methods identified, illustrating selected methods in example meta-analysis scenarios.

RESULTS

For missing standard deviations (SDs), following screening of 503 articles, fifteen methods were identified in addition to those reported in a previous review. These included Bayesian hierarchical modelling at the meta-analysis level; summary statistic level imputation based on observed SD values from other trials in the meta-analysis; a practical approximation based on the range; and algebraic estimation of the SD based on other summary statistics. Following screening of 1124 articles for methods estimating the mean, one approximate Bayesian computation approach and three papers based on alternative summary statistics were identified. Illustrative meta-analyses showed that when replacing a missing SD the approximation using the range minimised loss of precision and generally performed better than omitting trials. When estimating missing means, a formula using the median, lower quartile and upper quartile performed best in preserving the precision of the meta-analysis findings, although in some scenarios, omitting trials gave superior results.

CONCLUSIONS

Methods based on summary statistics (minimum, maximum, lower quartile, upper quartile, median) reported in the literature facilitate more comprehensive inclusion of randomised controlled trials with missing mean or variability summary statistics within meta-analyses.

Evaluation of different fibers and biodentine as alternates to crown coverage for endodontically treated molars: An in vitro study

OBJECTIVE

The objective of this study is to evaluate the fracture resistance of newer restorative materials that could serve as an alternate to crown coverage.

MATERIALS AND METHODS

Forty extracted human mandibular molar teeth were selected for this study and were divided into four groups (n = 10). All the teeth in the experimental groups (Group 2-4) were subjected to access cavity preparation with roughly 1.5 mm of tooth structure remaining throughout the circumference. Group 1: Intact teeth used as control. Group 2: Access cavities reinforced with biodentine. Group 3: Inner circumference of access cavities reinforced with polyethylene fiber and nano-hybrid composite. Group 4: Access cavities were reinforced with fiber reinforced composite. All the teeth were subjected to fracture resistance using universal testing machine.

RESULTS

The results of the study were evaluated statistically using one-way ANOVA and Tukey post hoc test. Group 2 demonstrated the least mean values of fracture resistance and was significantly different from the control and other experimental groups. Statistically significant difference among Groups 1, 3, and 4 was not found.

CONCLUSION

Within the limitation of this in vitro study, it can be concluded that fiber reinforced composite and polyethylene fibers with nanohybrid composite could serve as an alternate to crown coverage.

Restoration of the root canal treated tooth

When considering endodontically treated teeth, the quality of the restoration is important from the outset. It sheds light into possible causes of pulp necrosis or failure of endodontic treatment and influences the outcome of future endodontic treatment. A tooth undergoing endodontic treatment requires an effective coronal seal during and following completion of endodontic treatment. This paper discusses, using the available literature, the maintenance of optimal coronal seal and coronal integrity during and after root canal treatment.

Influence of Gender on the Patient's Assessment of Restorations on the Upper Anterior Teeth

OBJECTIVE

The aim of this study was to assess the level of patients' satisfaction with appearance of maxillary anterior teeth restorations and to determine if there is a significant difference in patients' assessment of restoration appearance with regard to gender.

MATERIALS AND METHODS

Two hundred subjects evaluated the colour, anatomical shape and surface texture of maxillary anterior teeth restorations (composite fillings, acrylic faceted metal crowns, porcelain-fused-to-metal crowns and all-ceramic crowns) in comparison with adjacent natural teeth. The data were expressed in patients' average assessment scores for colour, anatomical shape and surface texture as well as overall patients' average assessment scores for every type of restoration and overall patients' average assessment scores for colour, anatomical shape and surface texture of all the restorations in general. Patients also assessed the general impression of their maxillary anterior teeth restorations and rated it as satisfactory or unsatisfactory.

RESULTS

There was a statistically significant gender difference in patient assessment of colour and surface texture for composite fillings and the overall patient average assessment score for colour of all assessments (p <0.05). Women were more dissatisfied with the general impression of their restorations on the upper teeth than men (p >0.05). Only overall patients' average assessment score for composite restorations almost reached the level of significance (p = 0.069) on patients' general impression.

CONCLUSION

Colour of the restorations and the composite material are significant factors which affect dental appearance of maxillary anterior teeth in patients.