Systematic review fracture resistance of endodontically treated posterior teeth restored with fiber reinforced composites- a systematic review.

BACKGROUND: Large cavity designs and access cavities impair endodontically treated tooth fracture resistance. As the tooth's strength is known to reduce significantly after the root canal treatment, occlusal loading as a result of functions such as chewing, biting and certain parafunctional tendencies makes the endodontically treated tooth vulnerable to fracture. Hence, after endodontic treatment, it is vital to give adequate and appropriate restorative material to avoid tooth fractures. Accordingly, the choice of such restorative material should be dictated by the property of fracture resistance. OBJECTIVE: The goal of this study was to conduct a systematic review and critical analysis of available data from in vitro studies examining the fracture resistance of endodontically treated posterior teeth restored with fiber-reinforced composites. METHODOLOGY: The Preferred Reporting Items for Systematic Review and Meta-Analysis (PRIS-MA) Statement was used to guide the reporting of this systematic review A comprehensive literature search was performed using MEDLINE (via PubMed), Scopus, ScienceDirect, Google Scholar, and LILACS. A manual search of the reference lists of the articles was also performed. The databases provided a total of 796 studies from the electronic systematic search. The databases provided a total of 796 studies from the electronic systematic search. Two reviewers scrutinized the papers for eligibility based on inclusion/exclusion criteria and extracted data. The studies were assessed for their potential risk of bias. Based on modified JBI & CRIS (checklist for reporting in vitro studies) guidelines, along with the methodology and treatment objective, we have formulated 13 parameters specifically to assess the risk of bias. A total of 18 studies met the inclusion criteria and were included for qualitative analysis. Considering the high heterogeneity of the studies included, a meta-analysis could not be performed. RESULTS: The majority of the included studies had a moderate or high risk of bias. When compared to traditional hybrid composites, fiber-reinforced composites showed increased fracture resistance of endodontically treated teeth in the majority of investigations. On the other hand, limited evidence was found for the bulk fill composites. Moreover, moderate evidence was found for the fracture resistance of inlays and fiber posts with fiber-reinforced composites for core build-up in endodontically treated teeth. No evidence could be found comparing the fracture resistance of endo crowns and fiber-reinforced composites in endodontically treated teeth. CONCLUSION: According to the research, using fiber-reinforced composites instead of conventional hybrid composites improves the fracture resistance of endodontically treated teeth. However, there was a high risk of bias in the research considered. No judgments could be reached about the superiority of one material over another based-on comparisons between other core restorations.

Evaluation of the influence of various restoration techniques on fracture resistance of endodontically treated teeth with different cavity wall thicknesses.

AIMS: The aim of this study was to compare the effect of different restoration techniques on fracture resistance of endodontically treated teeth with different wall thicknesses. MATERIALS AND METHODS: Extracted and endodontically treated 210 premolars were randomly divided into three thickness groups [2 mm (A), 1.5 mm (B), and 1 mm (C)] and, each group was further divided into seven restoration subgroups (n = 10): direct composite (control) (K), composite with fiber on cavity floor (KT), composite with fiber on occlusal level (KO), fiber post and composite (FP), inlay (L), fiber on cavity floor and inlay (LT), and inlay and fiber on occlusal level (LO). Fracture test was performed, and data were compared with Kruskal-Wallis and Mann-Whitney U tests (P < 0.05). RESULTS: There were no differences between the subgroups in A and C statistically (P > 0.05). However, in B, KO subgroup showed statistically higher values (P = 0.039). CONCLUSION: Wall support of 2 mm was adequate, and support of 1 mm was completely insufficient. When the wall thickness was 1.5 mm, direct restoration with fiber at the occlusal level significantly improved resistance.

Complications of an Ageing Dentition Part 1: Occlusal Trauma and Cracked Teeth.

A growing problem in dentistry is complications associated with failing amalgam restorations that have been in place for many years. At present, there is a wide variety of treatment options available in the clinician's armamentarium when this situation arises, however, without the correct diagnosis, the prognosis for the tooth may quickly diminish, despite the clinician's best efforts. A confusing array of symptoms and failures may confound even the most experienced dentist, which will inevitably lead to invasive and time consuming approaches in a desperate attempt to rectify the initial problem. This paper, the first part of a three-part series, discusses the possible aetiological factors responsible for restoration failure, including occlusal issues and cracks within the tooth structure. The second part of the series will focus on restorative options and root-treated teeth. The third, and final, part of the series will provide an overview of the previous papers and conclude with a case report. Clinical relevance: Failure of amalgam restorations is a commonly encountered clinical problem in general practice and no one case presents in the same way. A competent diagnosis regarding the occlusion and tooth structure, followed with implementation of the most appropriate, minimally invasive treatment option, requires an adequate knowledge of current literature.

[A follow-up report of an uncomplicated crown fracture case starting from first-aid to the final definitive rehabilitation based on the experience]. / Fractura coronae non complicata diagnózisú eset bemutatása a gyermekkori elsosegélytol a végleges rehabilitációig.

Ten years ago a female child, who suffered an accident on her upper central incisors arrived in the dentistry-clinic. She was diagnosed with an uncomplicated crown fracture, whose follow-up story from first-aid to the final definitive rehabilitation with anterior press ceramic veneer will be shown. This publication analyses all the various kinds of possible therapies and connections with the uncomplicated crown fracture-type dental injuries according to the age of the patients and deduces how and why the adequate therapy and follow-up were choosen in this case.

Influence of cusp coverage on the fracture resistance of premolars with endodontic access cavities.

AIM: To assess the influence of cusp reduction and coverage with composite resin on the fracture resistance of premolars with prepared access cavities. METHODOLOGY: Endodontic access cavities were prepared in 60 premolar teeth that were divided into four test groups: R1, R2, R3 and NR (n=15). In all test groups, MOD cavities were prepared and extended towards one of the cusps. The remaining cusp-wall thickness was: 1-1.5 mm in R1, 1.5-2 mm in R2 and 2-3 mm in both R3 and NR groups. In addition, in group R1, R2 and R3 the same cusp was reduced in height to 3.5 mm. Cuspal coverage and MOD restorations were performed using composite resin. Ten intact premolars served as positive controls and another ten MOD-prepared unrestored premolars as negative controls. Teeth were submitted to cyclic fatigue of 1.2 million cycles. A compressive load was applied 30° to the long axis of the teeth until fracture. Fracture loads were recorded and the means and the Confidence Intervals were compared. RESULTS: The mean fracture resistance of each of the cusp-reduced groups R1, R2 and R3 (603, 712 and 697 N, respectively) was significantly higher than the non-reduced cusp group (305 N) and was comparable to the intact-premolar group (653 N). CONCLUSIONS: Cusp reduction and coverage with composite resin significantly increased the fracture resistance of premolar teeth with MOD and endodontic access cavities.

Intentional replantation: a procedure as a last resort.

AIM: To address the indications, contraindications, surgical procedure, complications following treatment, factors influencing the results and success rate of intentional replantation procedure. BACKGROUND: Intentional replantation is extraction of a tooth to do extraoral root canal therapy, curettage of apical lesion when present, and its replacement in its socket. It has been proposed as an alternative to routine extraction; however, it should be considered a last resort because the root may be fractured during extraction. RESULTS: The success rate of intentional replantation is far below than routine endodontic treatment or apical surgery. Difficultness of tooth extraction, the possibility of fracture during extraction and the risk of external resorption are some limitations of this treatment. The most common causes of failure in intentionally replanted teeth are external inflammatory resorption or replacement resorption and ankylosis caused by periodontal ligament damage. CONCLUSION: The success rate up to 95% with an average retention of 3 to 5 years, has been reported. CLINICAL SIGNIFICANCE: In some cases, endodontic retreatment or apical surgery is impossible or impractical. In these situations, intentional replantation may be considered as a last resort for preserving the tooth, so all clinicians should know about its indications/contraindications, surgical procedure and complications following treatment.

Maxillofacial injury related to an exploding e-cigarette.

Electronic cigarettes (also known as e-cigarettes or electronic nicotine delivery systems) were invented in China in 2003 then introduced to the British market in 2007. They remain popular among the public and are deemed to be effective in reducing tobacco smoking (the UK being one of the first countries to embrace them in a harm reduction policy). However, reports in the media of e-cigarettes exploding are of concern, considering the potential functional and psychological impairment that lifelong disfigurement will cause, especially given their uptake among people of any age. We present a case of this rare, but dramatic, effect of e-cigarette use as a warning to the public.

Ridge preservation in cases requiring tooth extraction during endodontic surgery: a case report.

AIM: To provide a treatment option to endodontists performing surgery that will enhance ridge preservation when tooth extraction is required. SUMMARY: A 47-year-old woman was referred to an endodontic practice for apical root-end resection of tooth 22 because of refractory periradicular disease. Radiographic examination revealed a large periradicular lesion, 5 mm in diameter and a root-end filling at the root apex. The treatment plan included exploratory surgery and apical root-end resection. A vertical root fracture was diagnosed and the decision was made to extract the tooth. The socket was grafted with a cancellous bovine bone and covered with a resorbable collagen membrane. Follow-up examination revealed favourable bone healing with formation of a new cortical plate and the preservation of soft tissue width and height in the aesthetic area. KEY LEARNING POINTS: The principles of guided bone regeneration. Preserving or reconstructing the extraction socket. Enhances the ability to restore function and provide aesthetically pleasing restorations to patients without violating the predictability and function of the prostheses.

Root Reinforcement after Obturation with Calcium Silicate-based Sealer and Modified Gutta-percha Cone.

INTRODUCTION: A root canal obturated with a calcium silicate-based sealer (bioceramic sealer [BCS]) and a modified gutta-percha cone (bioceramic cone [BCC]) might improve the fracture resistance of the root. The objective of this study was to evaluate root reinforcement of a bioceramic cone/sealer (TotalFill; FKG Dentaire SA, La Chaux-de-Fonds, Switzerland) by investigating the fracture resistance, push-out bond strength, sealer penetration, and modulus of elasticity (MOE) in comparison with gutta-percha/AH Plus (Dentsply Maillefer, Tulsa, OK) (GP/AH). METHODS: Eighty-four roots from bilateral mandibular premolars were prepared. For fracture resistance, 40 teeth were randomly divided into 4 groups (n = 10 each): intact roots (negative control), prepared roots (positive control), and the roots obturated with either BCC/BCS or GP/AH. Root canals were obturated with the matched single-cone technique and vertically loaded with a spreaderlike tip until fracture. For push-out bond strength (n = 10 each), coronal, middle, and apical root slices of BCC/BCS and GP/AH were loaded with a cylindrical plunger, and failure modes were determined. Sealer penetration of BCC/BCS and GP/AH (n = 12 each) was evaluated for the maximum depth and the circumferential and total area of penetration at the coronal, middle, and apical levels using confocal laser scanning microscopy. The MOE was investigated according to ISO 4049:2000. RESULTS: The fracture load of BCC/BCS, GP/AH, and the intact roots was not significantly different but significantly higher than the prepared, nonobturated roots. BCC/BCS provided a higher bond strength, maximum depth, and circumferential penetration at the apical root level as well as a greater sealer penetration area at all levels compared with GP/AH. The MOE of all materials was much lower than dentin. CONCLUSIONS: BCC/BCS and GP/AH bonded and reinforced the prepared roots; their fracture resistances were similar to the intact roots.

Biomechanical Effects of Bonding Pericervical Dentin in Maxillary Premolars.

INTRODUCTION: Pericervical dentin (PCD) loss may increase root fracture propensity in root-filled teeth. This study evaluated the impacts of bonding PCD with composite resin (CR) on radicular microstrain distribution and load at failure of root-filled maxillary premolars. METHODS: Ten single-canal maxillary premolars decoronated 2 mm coronal to the cementoenamel junction (CEJ) had canals enlarged with ProTaper Universal instruments (Dentsply Tulsa Dental Specialties, Tulsa, OK) to F3. They were root filled with gutta-percha (GP) to the CEJ and restored with Cavit (3M Deutschland GmbH, Neuss, Germany) (GP group, n = 5) or 6 mm apical to the CEJ and restored with bonded CR to simulate bonding of PCD (bonded PCD group, n = 5). Digital moiré interferometry was used to evaluate pre- and postoperative whole-field microstrain distribution in the root dentin under physiologically relevant loads (10-50 N). Another 30 premolars, similarly treated as groups 1 and 2 or left untreated as controls (n = 10/group), were subjected to cyclic loads (1.2 million cycles, 45 N, 4 Hz) followed by uniaxial compressive load to failure. Mechanical data were analyzed with 1-way analysis of variance and the post hoc Tukey test at a 5% level of significance. RESULTS: Microstrain distribution showed bending and compressive patterns at the coronal and apical root dentin, respectively. In the GP group, microstrain distribution was unaltered. In the bonded-PCD group, different microstrain distribution suggested stiffening at the PCD. The load at failure did not differ significantly for the GP, bonded PCD, and control groups (P > .05). CONCLUSIONS: CR bonding of PCD might impact the biomechanical responses in maxillary premolar roots at low-level continuous loads. The effect of this impact on root fracture loads when subjected to cyclic load warrants further investigation.

Age-Related Pattern of Dental Trauma in a Nigerian Tertiary Health Institution

Abstract Objective: To evaluate the pattern of traumatic dental injuries among children, adolescents, and adults. Material and Methods: This was a cross-sectional analytic study of children and adults who presented with dental trauma. Data utilized for this study were sociodemographic characteristics, history of the traumatic incident, presenting complaints, traumatized teeth and classification of the traumatized tissues using Ellis and Davey's classification. Results: A total of 163 participants with 307 traumatized teeth were included in the study. The participants' age ranged from 2 years to 75 years, with a mean age of 25.36 ±15.4 years. Children <10 years were the least represented (14.7%), adolescents 10-19 years accounted for 23.9%., young adults 20 to 40 years were the most represented (44.8%) and older adults >40 years (16.6%). A higher proportion of the study participants were female 83 (50.9%) and the most prevalent complaint was broken teeth (57.1%) The most prevalent aetiology of the trauma documented was fall (36.2%). The most prevalent injury type was extended crown fracture with noticeable dentinal involvement without pulp exposure. There was a statistically significant association between injury type, aetiology and age group. Conclusion: Traumatic dental injuries affect children, adolescents and adults alike. The central incisors were the most vulnerable teeth across all age groups. Age was significantly associated with the etiology of dental trauma and injury type (AU).

Placement and replacement of restorations by selected practitioners.

BACKGROUND: There are few Australian data on the reasons for placement and replacement of restorations, and the extent to which these are carried out in general practice. METHODS: A survey was carried out of approximately 100 consecutive restorations placed by each of 28 general dental practitioners. The data were coded and statistically analyzed for various associations. RESULTS: Resin composite was used twice as frequently as amalgam as a restorative material, and nearly four times as often as glass-ionomer cement. Secondary caries was the principal reason for replacing restorations, affecting predominantly amalgam restorations in Class I and Class V cavities. Teeth restored with amalgam fractured nearly twice as often as teeth restored with resin composite. The average ages of amalgam, resin composite and glass-ionomers at replacement were 13.6, 7.1 and 5.7 years respectively. CONCLUSIONS: Amalgam has the longest clinical service life, but is associated with more tooth fracture. Secondary caries is the main reason for replacing restorations. The anti-cariogenic effect of glass-ionomer cement is equivocal.

Fracture resistance of endodontically treated roots with oval canals restored with oval and circular posts.

INTRODUCTION: The aim of the present study was to evaluate the effects of post space preparations with circular and oval post drills and the placement of oval and circular posts on the fracture strength of roots with oval canals. METHODS: Seventy mandibular premolars with oval root canals were decoronated. Fourteen teeth were used as a control group (group 1), and the root canals of the remaining teeth were prepared up to size #30. The root canals were filled, and the samples were randomly divided into 4 experimental groups as follows: post space preparation with circular-shaped drills (group 2), post space preparation with oval-shaped drills (group 3), circular post placement (group 4), and oval post placement (group 5). A fracture strength test was performed on each specimen, and the data were statistically evaluated using 1-way analysis of variance and Tukey post hoc tests. RESULTS: The fracture strengths of the circular posts-placed group were higher than those of the oval post-placed group (P < .001). The post space preparation using oval-shaped drills significantly decreased the fracture strength of the roots compared with the control group (P < .001). CONCLUSIONS: Within the limitations of the present study, oval posts did not provide a higher fracture resistance to endodontically treated roots with oval canals compared with circular posts. Therefore, clinicians should be aware that oval posts are similar to circular posts in terms of enhancing the fracture resistance of roots with oval canals.

A three-dimensional finite-element stress analysis of an endodontically prepared maxillary central incisor.

This study is an application of a three-dimensional Finite-Element Method to investigate the changes in stress characteristics of a prepared maxillary central incisor. The purpose of this study was to analyze stress distributions in this tooth after simulated canal preparation and static loading. A maxillary central incisor was embedded in acrylic, sectioned, photographed, and digitized. A three-dimensional finite-element model was generated by a computer and appropriately modified to simulate canal preparation. Data identified the highest stress magnitudes to be located between the middle and coronal thirds of the root; an area clinically observed to be prone to fracture during treatment. In addition, the magnitude of generated stresses was directly correlated with the simulated prepared canal diameter. The development of a validated three-dimensional finite-element method could identify areas that may predispose a tooth to structural failure during condensation loads.

An evaluation of endodontically treated vertically fractured teeth.

For this survey, 92 vertically fractured endodontically treated teeth were evaluated clinically and radiographically before and after extraction. The maxillary second premolars (27.2%) and mesial roots of the mandibular molars (24%) were the most fractured teeth. In 67.4% of the teeth, a solitary buccal pocket was present; in 34.8%, a fistula frequently appeared closer to the gingival margin than to the apical area. A lateral radiolucency or a combination of lateral and periapical radiolucency was found in more than half of the cases. The general practitioners correctly diagnosed vertical root fracture in only one-third of the 92 fractured teeth in this survey.

Causes of accidental injuries to the teeth and jaws.

Almost one half of all the dental accidents recorded during this study occurred when the victim was moving and struck a stationary object. Falls and vehicles were about equally responsible for half of the accidents. Accident proneness seemed to be affected by age and sex with the teenage group reporting the most dental accidents (35.76%) and males reported dental accidents three times as often as females. Of orthodontic patients, 16.43 percent had a history of dental accidents in contrast to about five percent of the general population. From the limited data available, approximately three fourths of the persons reporting said no seat belts were available in their automobiles. The remaining one fourth had belts but they were not being used at the time of the dental injury. Right-handed victims tended to be injured on the right side of the mouth and jaw and left-handed victims exhibited more injuries on the left side. As was anticipated, a high percentage (23 percent) of the residents of a hospital for the mentally retarded exhibited dental injuries.

Fracture resistance of endodontically prepared teeth using various restorative materials.

This study compares the fracture resistance of endodontically treated premolars with modified types of cavity preparations and restoration with either amalgam or composite resin. The greatest influence on fracture resistance was the remaining tooth structure. The effect of adequate wall support on tooth strength was compared with intact unprepared teeth.

Mouth protectors and oral trauma: a study of adolescent football players.

A total of 754 junior high school and high school football players from the Birmingham, AL, area were studied to determine the extent of sports-related oral trauma among players. More than half the oral injuries and more than a third of the concussions were reported in sports other than football. Basketball and baseball players had a high prevalence of hard tissue oral trauma with virtually none of the players wearing mouth protectors. The results of this study indicate that current mouth protector designs are helpful in preventing hard tissue trauma, yet additional soft tissue protection is indicated in football mouth protector design.

Resin composite reinforcement of undermined enamel.

Studies have suggested that fracture resistance of undermined enamel increases when supported by a layer of bonded composite. Composite to reinforce enamel must have a secure foundation in dentin and/or enamel that is supported by dentin to perform optimally. A restorative technique is presented using resin composite material to support and reinforce undermined enamel that lacks dentinal support in traditional amalgam restorations. This technique is intended to conserve unsupported enamel cavity walls and weakened cusps in extensive Class I and II preparations.