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Journal of Pharmacy & Bioallied Sciences Feb 2024The study's objective is to evaluate the fracture resistance of a tooth that has had endodontic treatment and has been rebuilt using various post and core systems.
OBJECTIVES
The study's objective is to evaluate the fracture resistance of a tooth that has had endodontic treatment and has been rebuilt using various post and core systems.
MATERIALS AND METHODS
Thirty-six extracted premolar teeth of similar sizes were picked, and at random, they were separated into three groups: group A received stainless-steel posts, group B received zirconia fiber posts, and group C received glass fiber posts. Dual-cured resin cement was used to cement each post. The acrylic resin blocks have samples imbedded in them. Additionally, fracture loads were measured while a compressive force was given to the tooth at a crosshead speed of 1 mm/minute. The one-way analysis of variance F-test and Tukey's test were then used to analyze the results.
RESULTS
When the mean values and standard deviation were compared, it was found that glass fiber posts had the highest fracture resistance, followed by posts made of zirconia fiber, while stainless-steel posts had the lowest fracture resistance.
CONCLUSION
When compared to zirconia posts and stainless-steel posts, glass fiber posts had the highest level of fracture resistance.
PubMed: 38595599
DOI: 10.4103/jpbs.jpbs_949_23 -
Journal of Pharmacy & Bioallied Sciences Feb 2024Regenerative endodontic procedures (REPs) have emerged as a transformative approach to treating immature permanent teeth with necrotic pulp tissue.
BACKGROUND
Regenerative endodontic procedures (REPs) have emerged as a transformative approach to treating immature permanent teeth with necrotic pulp tissue.
MATERIALS AND METHODS
A prospective study was conducted, enrolling 100 patients with immature permanent teeth requiring REPs. All procedures were performed by a single experienced endodontist following established protocols. Patients were followed up for a minimum of 5 years' post-treatment. Clinical examinations, radiographic assessments, and patient-reported outcomes were recorded at regular intervals. Data were analyzed using statistical methods to determine the success rates, complications, and factors influencing long-term outcomes.
RESULTS
The results of this original research reveal a significant and sustained success rate for REPs. After a minimum follow-up period of 5 years, an arbitrary value of 92% for tooth survival was achieved. Radiographic assessments demonstrated consistent healing of apical lesions, and continued root development was observed in the majority of cases. Patient-reported outcomes indicated a high level of satisfaction with the procedure. Complications such as crown discoloration and tooth fracture occurred in a minority of cases but were effectively managed without compromising the overall success of REPs.
CONCLUSION
This original research provides strong evidence for the long-term success of REPs in the treatment of immature permanent teeth with necrotic pulp tissue. The high tooth survival rate, continued root development, and patient satisfaction support the efficacy of REPs as a reliable treatment option.
PubMed: 38595540
DOI: 10.4103/jpbs.jpbs_1023_23 -
Journal of Pharmacy & Bioallied Sciences Feb 2024Polyetheretherketone (PEEK) has a long history of usage in implant abutments, but it has not seen much applications in tooth-supported prosthetics. The purpose of this...
INTRODUCTION
Polyetheretherketone (PEEK) has a long history of usage in implant abutments, but it has not seen much applications in tooth-supported prosthetics. The purpose of this research was to examine the clinical performance of PEEK crowns as well as the level of patient satisfaction with them. The pilot study was designed as an longitudinal examination.
MATERIAL AND METHODS
Twenty patients each received a PEEK crown during the procedure. In total, 22 implants were inserted, with 11 going into the maxilla and 9 into the mandible. One operator was responsible for carrying out each phase of the procedure. The resin cement was used to lute the crowns that were produced. Baseline, 3 months, 6 months, and 1 year after the crowns were placed, they were evaluated for various parameters using Modified Ryge's Criteria. These evaluations were performed at intervals of 3 months, 6 months, and 1 year. In addition, a questionnaire was used at the same time to assess the level of satisfaction felt by patients. Fisher's exact test was utilized in the process of analyzing the data that were gathered.
RESULTS
According to the findings, 92.5% of the crowns met the modified version of Ryge's criterion for a satisfactory rating. Three crowns had a fracture recorded. There was some chipping off observed in five of the crowns. There was not any significant difference in the other factors that were examined. The periodontal health of these three patients showed a slight degree of variance ( = 0.02).
CONCLUSION
The capacity of PEEK crowns to create high-quality prostheses that were deemed satisfactory with a reasonably low rate of fracture during the relative mean duration of 1 year was established by the application of Modified Ryge's Criteria. The PEEK crowns demonstrated their ability to produce quality prostheses.
PubMed: 38595539
DOI: 10.4103/jpbs.jpbs_443_23 -
Journal of Pharmacy & Bioallied Sciences Feb 2024The application of the antioxidants after the teeth are bleached has been advocated to fasten the restorative process post-bleaching. The motive of this study was to...
INTRODUCTION
The application of the antioxidants after the teeth are bleached has been advocated to fasten the restorative process post-bleaching. The motive of this study was to examine and assess the micro-tensile binding strength of bleached enamel to the resin using a variety of antioxidant solutions. Finding the reason for the tooth fracture was the secondary outcome measured.
MATERIALS AND METHODS
An study was planned with 100 human extracted teeth, with 20 in each group with one as controls and 4 others tested for the antioxidants sodium ascorbate, epigallocatechin gallate, chitosan, and proanthocyanidin application. The bond strength of bleached enamel to the resin was well as the failure type was assessed after the values were noted and compared using the ANOVA and Tukey's methods keeping < 0.05 as significant.
RESULTS
Epigallocatechin gallate specimens displayed the maximum micro-tensile bond strength under the investigational circumstances, whereas controls displayed the lowest micro-tensile bond strength. There was statistical alteration in micro-tensile bond strengths between all the groups except between epigallocatechin gallate vs chitosan and sodium ascorbate vs proanthocyanidin. High statistical significance was seen between the control and the antioxidant groups as well as between sodium ascorbate and epigallocatechin gallate and chitosan.
CONCLUSION
The antioxidant chemicals significantly augmented the bond strength of bleached enamel to the resin that had been bleached. Also, when compared to the other experimental groups, epigallocatechin gallate and chitosan treatment displayed the greatest mean bond strength values.
PubMed: 38595474
DOI: 10.4103/jpbs.jpbs_433_23 -
The Journal of Prosthetic Dentistry Apr 2024Evidence comparing the survival of zirconia crowns with metal-ceramic crowns is sparse. Knowledge of their survival and a comparison of their clinical outcomes would...
STATEMENT OF PROBLEM
Evidence comparing the survival of zirconia crowns with metal-ceramic crowns is sparse. Knowledge of their survival and a comparison of their clinical outcomes would improve clinical decision making.
PURPOSE
The purpose of this university-based study was to compare the survival, failures, biological and technical complications encountered with zirconia and metal-ceramic crowns restored and followed up over a similar period.
MATERIAL AND METHODS
This retrospective chart review consisted of 403 patients treated at the University of Toronto, Faculty of Dentistry, predoctoral dental clinic in whom zirconia (n=209) and metal-ceramic (n=306) crowns were inserted between September 2015 and July 2016 and followed for up to 7 years. Outcome measures included failure, causes for failure, and complications associated with survival. Inferential statistical analysis included the chi-squared test, t test, Mann-Whitney test, Bonferroni-adjusted z-test, Kaplan-Meier survival test, and logistic regression to examine differences between crown types and explore crown failures (α=.05).
RESULTS
The mean follow-up period was 3.00 years (median 2.58 years). Forty-one (8.0%) crowns had no follow-up, with no difference in follow-up between crown type: metal-ceramic n=23(7.5%), zirconia n=18(8.6%), χ²(1)=0.20, P=.652). Excluding those with no follow-up, the follow-up time between metal-ceramic (mean=3.07, median=2.58) and zirconia (mean=3.54, median=3.32) crowns was statistically similar (P=.052). There were 62 anterior crowns (12.0%) and 453 posterior crowns (88.0%), χ²(1)=22.40, P<.001, with no difference between groups. Overall, 44 crowns (8.5%) failed, 30 (9.8%) metal-ceramic and 14 (6.7%) zirconia, with no statistical difference in proportion of failed crowns between groups (χ²(1)=1.53, P=.216). There were 35 crowns with biological failures (6.8%), 26 (8.5%) in the metal-ceramic and 9 (4.4%) in the zirconia group, with no statistical difference between groups (χ²(1)=3.33, P=.068). Nine crowns had technical failures (1.7%), 4 (1.4%) in the metal-ceramic group and 5 (2.5%) in the zirconia group, with no statistical difference between groups (χ²(1)=0.73, P=.394). Biological (79.5%) rather than technical complications were found to be the most frequent cause of failure, goodness-of-fit χ²(1)=15.36, P<.001. Tooth fracture (50.0%) specifically was found to be the most frequent cause of failure, χ²(3)=21.27, P<.001. The total number of crowns that survived was 471 (91.5%); 276 (90.1%) were metal-ceramic and 195(93.3%) zirconia. The survival time (years) for metal-ceramic was mean=6.26, 95% CI [6.01-6.51] and for zirconia crowns mean=6.54, 95% CI [6.31-6.77]. Of the crowns that survived, 370 (78.6%) had no clinical complications, and 101 (21.4%) crowns demonstrated similar clinical complications, with no statistical differences between groups.
CONCLUSIONS
Within the study follow-up time, the survival of monolithic zirconia and metal-ceramic crowns was 91.5%, with similar clinical complications between groups. Biological complications, especially tooth fracture, were a significantly more frequent complication with both types of crowns.
PubMed: 38580582
DOI: 10.1016/j.prosdent.2024.02.028 -
Dental Materials : Official Publication... May 2024Lithium silicate-based glass ceramics have evolved as a paramount restorative material in restorative and prosthetic dentistry, exhibiting outstanding esthetic and... (Review)
Review
OBJECTIVES
Lithium silicate-based glass ceramics have evolved as a paramount restorative material in restorative and prosthetic dentistry, exhibiting outstanding esthetic and mechanical performance. Along with subtractive machining techniques, this material class has conquered the market and satisfied the patients' needs for a long-lasting, excellent, and metal-free alternative for single tooth replacements and even smaller bridgework. Despite the popularity, not much is known about the material chemistry, microstructure and terminal behaviour.
METHODS
This article combines a set of own experimental data with extensive review of data from literature and other resources. Starting at manufacturer claims on unique selling propositions, properties, and microstructural features, the aim is to validate those claims, based on glass science. Deep knowledge is mandatory for understanding the microstructure evolution during the glass ceramic process.
RESULTS
Fundamental glass characteristics have been addressed, leading to formation of time-temperature-transformation (TTT) diagrams, which are the basis for kinetic description of the glass ceramic process. Nucleation and crystallization kinetics are outlined in this contribution as well as analytical methods to describe the crystalline fraction and composition qualitatively and quantitatively. In relation to microstructure, the mechanical performance of lithium silicate-based glass ceramics has been investigated with focus on fracture strength versus fracture toughness as relevant clinical predictors.
CONCLUSION
Fracture toughness has been found to be a stronger link to initially outlined manufacturer claims, and to more precisely match ISO recommendations for clinical indications.
Topics: Ceramics; Silicates; Materials Testing; Glass; Surface Properties; Dental Materials; Crystallization; Lithium Compounds; Dental Porcelain
PubMed: 38580561
DOI: 10.1016/j.dental.2024.03.006 -
World Journal of Stem Cells Mar 2024The bone remodeling during orthodontic treatment for malocclusion often requires a long duration of around two to three years, which also may lead to some complications...
BACKGROUND
The bone remodeling during orthodontic treatment for malocclusion often requires a long duration of around two to three years, which also may lead to some complications such as alveolar bone resorption or tooth root resorption. Low-intensity pulsed ultrasound (LIPUS), a noninvasive physical therapy, has been shown to promote bone fracture healing. It is also reported that LIPUS could reduce the duration of orthodontic treatment; however, how LIPUS regulates the bone metabolism during the orthodontic treatment process is still unclear.
AIM
To investigate the effects of LIPUS on bone remodeling in an orthodontic tooth movement (OTM) model and explore the underlying mechanisms.
METHODS
A rat model of OTM was established, and alveolar bone remodeling and tooth movement rate were evaluated micro-computed tomography and staining of tissue sections. , human bone marrow mesenchymal stem cells (hBMSCs) were isolated to detect their osteogenic differentiation potential under compression and LIPUS stimulation by quantitative reverse transcription-polymerase chain reaction, Western blot, alkaline phosphatase (ALP) staining, and Alizarin red staining. The expression of Yes-associated protein (YAP1), the actin cytoskeleton, and the Lamin A/C nucleoskeleton were detected with or without YAP1 small interfering RNA (siRNA) application immunofluorescence.
RESULTS
The force treatment inhibited the osteogenic differentiation potential of hBMSCs; moreover, the expression of osteogenesis markers, such as type 1 collagen (COL1), runt-related transcription factor 2, ALP, and osteocalcin (OCN), decreased. LIPUS could rescue the osteogenic differentiation of hBMSCs with increased expression of osteogenic marker inhibited by force. Mechanically, the expression of LaminA/C, F-actin, and YAP1 was downregulated after force treatment, which could be rescued by LIPUS. Moreover, the osteogenic differentiation of hBMSCs increased by LIPUS could be attenuated by YAP siRNA treatment. Consistently, LIPUS increased alveolar bone density and decreased vertical bone absorption The decreased expression of COL1, OCN, and YAP1 on the compression side of the alveolar bone was partially rescued by LIPUS.
CONCLUSION
LIPUS can accelerate tooth movement and reduce alveolar bone resorption by modulating the cytoskeleton-Lamin A/C-YAP axis, which may be a promising strategy to reduce the orthodontic treatment process.
PubMed: 38577236
DOI: 10.4252/wjsc.v16.i3.267 -
Journal of the American Dental... May 2024Orthodontic treatment for patients with dentinogenesis imperfecta (DGI) can be risky because of the fragility of their dental hard tissue. Although the Invisalign (Align...
BACKGROUND
Orthodontic treatment for patients with dentinogenesis imperfecta (DGI) can be risky because of the fragility of their dental hard tissue. Although the Invisalign (Align Technology) clear aligner system should be a suitable orthodontic appliance for patients with DGI, to the authors' knowledge, there has been no related research.
CASE DESCRIPTION
A 28-year-old woman with DGI sought treatment with a 1 mm open bite, edge-to-edge occlusion of the central incisors, and a bilateral Class III cusp-to-cusp molar relationship. Invisalign was applied for her treatment, and after 3 and one-half years of orthodontic therapy, a normal overjet and overbite were achieved, accompanied by retraction of the lower lip as well as a bilateral Class I molar relationship. In addition, there was no iatrogenic injury to the patient's teeth.
PRACTICAL IMPLICATIONS
The Invisalign system may be a suitable orthodontic appliance for patients with DGI because clear aligners lessen the tensile stress to the teeth, decrease the number and area of bonds to the teeth, and offer protective effects through a full wrap of plastic that covers the crowns of the teeth.
Topics: Humans; Female; Adult; Dentinogenesis Imperfecta; Orthodontic Appliances, Removable; Tooth Movement Techniques; Orthodontics, Corrective; Orthodontic Appliance Design
PubMed: 38573273
DOI: 10.1016/j.adaj.2024.01.007 -
Frontiers in Dentistry 2024Reconstructing severely damaged teeth has always presented a challenge when the remaining crown structure is limited, often requiring retention from the root canal using...
Reconstructing severely damaged teeth has always presented a challenge when the remaining crown structure is limited, often requiring retention from the root canal using intracanal posts. However, the real challenge is when the root canal walls are also weak, and there is a high risk of vertical root fracture due to the wedging forces of a rigid post. This case report presents a tooth with extremely flared (0.3mm) root canal walls, successfully restored with a newly introduced polymer made of polyether ether ketone (PEEK), with one-year follow-up. Due to its close elastic modulus to dentin, capacity to bond effectively to tooth structure, shock-absorbing properties, and thereby facilitating favorable stress distribution, utilizing this material for an intracanal post has the potential to mitigate the risk of fractures often associated with cast metal posts. It combines the good fitness of cast posts with the low modulus of elasticity and optical properties of prefabricated fiber posts.
PubMed: 38571899
DOI: 10.18502/fid.v21i3.14760 -
Case Reports in Dentistry 2024This case report details the esthetic rehabilitation of a 32-year-old male patient suffering from sleep bruxism, primarily manifesting as a fracture and significant loss...
This case report details the esthetic rehabilitation of a 32-year-old male patient suffering from sleep bruxism, primarily manifesting as a fracture and significant loss of tooth structure in the anterior maxillary central incisors. To address these concerns, the patient underwent a restorative treatment involving the application of semidirect resin composite veneers on the maxillary incisors and direct resin composite restoration on the incisal regions of the maxillary canines. This approach not only restored the functional integrity of the teeth but also significantly enhanced the patient's esthetic appearance.
PubMed: 38560367
DOI: 10.1155/2024/5572481