Evaluation of Related Factors in the Failure of Endodontically Treated Teeth: A Cross-sectional Study

Time assessment for final restoration of endodontically treated teeth in a university clinic setting: An observational study

Background

The aim was to quantify the time elapsed between tooth reconstruction and the end of endodontic treatment, and to assess differences according to sex, age, and tooth group.

Material and Methods

A retrospective study was conducted with patient clinical records. Data relating to patient characteristics, treated teeth, endodontic treatment, and subsequent restorative treatment were recorded.

Results

For this study, 355 endodontically treated teeth by undergraduate students during 2019 were included. 24 teeth (6.76 %) were not restored, more direct (86.4 %) than indirect (13.6 %) restorations were performed, and the most frequent type of restoration was complex filling. The mean elapsed time from endodontic completion to direct restoration was 7 days, with a minimum of 0 and a maximum of 90 days. For indirect restorations the mean elapsed time was 21 days.

Conclusions

The median elapsed time for endodontic tooth reconstruction was 7 days (IQR = 7), however, treatment should not be considered completed until the tooth has been properly restored. In cases where an indirect restoration was also necessary, the median elapsed time was higher (21 days; IQR = 31.5).

Eight-year retrospective study investigating tooth survival after primary non-surgical root canal treatment in a UK military cohort

INTRODUCTION

Root canal treatment (RCT) plays an important role in preserving the dentition by deferring other invasive treatments. Data on tooth survival and predictive factors for tooth loss after RCT in the military cohort are lacking. This investigation aimed to determine the proportion of teeth surviving in an 8-year period after RCT and identify potential predictive factors for tooth loss in a UK military cohort.

METHODOLOGY

A retrospective review of an integrated electronic health record for military patients who had received RCT was performed in a random sample of 205 patients (n=219 root-filled teeth) who had received RCT between 1 January 2011 and 1 January 2012. Tooth survival was defined as tooth presence, regardless of signs or symptoms, and measured from the point of root filling until either the end of the designated study period or time of extraction. Survival was evaluated using Kaplan-Meier estimates and association with tooth loss using the χ2 test. Potentially significant predictive factors were investigated using univariate Cox regression.

RESULTS

Tooth survival following RCT was 98% after 24 months; 88% after 48 months; 83% after 72 months; and 78% after 96 months. Four predictive factors were found to affect tooth loss as follows: preoperative pain (HR=3.2; p<0.001), teeth with less than two proximal contacts (HR=3.0; p=0.01), teeth with cores involving more than two surfaces (HR=2.0; p=0.03) and postoperative unscheduled dental attendances (UDA) (HR=2.7; p=0.01).

CONCLUSIONS

Within the limitations of this study, the presence of preoperative pain; teeth with less than two proximal contacts or with cores involving more than two tooth surfaces; and occurrence of postoperative UDA were found to significantly increase the hazard of tooth loss.

Predicting early endodontic treatment failure following primary root canal treatment

BACKGROUND

Understanding when and why endodontic treatments fail could help clinicians make prognoses and thus improve treatment outcomes. This study was aimed to assess potential predictors of early endodontic treatment failure. We explored factors contributing to the failure of initial root canal treatment were explored, with a specific emphasis on evaluating the influence of the time elapsed since the initial treatment.

METHODS

This retrospective cohort study enrolled 1262 patients who sought endodontic treatment at our department and 175 patients were included for analysis. Potential causes of endodontic treatment failure were investigated, such as inadequate obturation quality, inadequate coronal status, the presence of additional untreated canals, anatomical complexity, instrument separation, iatrogenic perforation, cracks, and endodontic-periodontal lesions. The patients were divided into "short-term" and "long-term" groups depending on the time that had passed since the initial treatment (i.e., < 5 and > 10 years, respectively). The causes of failure in the short-term and long-term group were analyzed and compared using logistic regression analyses. Subgroup analysis was performed according to the number of years since the initial treatment in the short-term group to further investigate the association between the time and cause of failure (i.e., < 1, 2, 3, and 4 years, respectively).

RESULTS

Untreated additional canals were present in 21.7% of all cases, and in 36.9 and 6.4% of cases in the short-term and long-term groups, respectively. Multivariable analysis showed that the presence of untreated additional canals was significantly associated with short-term compared to long-term failure. Untreated additional canals were also associated with endodontic failure within 1, 2, 3, and 4 years.

CONCLUSIONS

The presence of untreated additional canals was a predictor of endodontic failure within 5 years following initial root canal treatment. To optimize long-term prognosis, it is important to detect and treat all root canals during the initial treatment.

Evaluation of roots, root canal morphology, and bilateral symmetry of maxillary first molars in a Syrian subpopulation using cone beam computed tomography

OBJECTIVE

Successful endodontic treatments require a comprehensive knowledge of the root canal anatomy, so this study aimed to investigate the number of roots, configurations of root canals, and their bilateral symmetry of maxillary first molars in the Syrian subpopulation, and also the effect of gender on this symmetry.

MATERIALS AND METHODS

The study sample consisted of 250 cone beam computed tomography images (140 for females; and 110 for males), including 500 maxillary first molars. Images were investigated by two endodontists. Root number and canal configuration in each root were recorded, according to Vertucci classification, by studying the image at all levels (axial, coronal, sagittal, oplique, and three-dimensional) to assess the bilateral symmetry and its relation to gender. Statistical analysis was performed with SPSS and the χ2 test was used to compare the bilateral symmetry in males and females.

RESULT

The most common shape of the maxillary first molars was three roots (97.6%). All the roots are symmetrical by 100% in both genders. The root canal configuration was mainly Vertucci type I classification in the distobuccally (73.6%), and palatal root (98%). While the most common types in mesial root were type II (33.3%), this root showed all different types of Vertucci classifications except type VIII, and the proportion of symmetry was (37.2%) without significant difference between the gender (p = .441).

CONCLUSION

Most maxillary first molars in a Syrian population were three-rooted with four root canals (type II), the numbers of roots achieved perfect symmetry 100%, and higher than symmetry ratios in the number of canals and canals configurations (37.2%).

A literature review of local and systemic considerations for endodontic treatments in older adults

OBJECTIVES

The aim of this literature review was to summarise the clinical important findings on the endodontic treatment outcome in older patients (≥60 years old) with pulpal/periapical disease considering local and systemic factors from a body of knowledge that is heterogeneous in methods or disciplines.

BACKGROUND

Due to the increasing number of older patients in the endodontic practice, and the current trend for tooth preservation, the need for clinicians to have a better understanding of age-related implications that may influence the required endodontic treatment in older adults to retain their natural dentition is indispensable.

METHODS

PubMed/Medline and Embase was searched by a medical librarian using specific terms based on inclusion/exclusion criteria. The reference list was hand-seached for additional relevant publications between 2005-2020. A combination of these terms was performed uing Boolean operators and MeSH terms.

RESULTS

Of the 1577 publications identified manually and electronically, 25 were included to be fully reviewed by the examiners. The data was derived from three systematic reviews, one systematic and meta-analysis, three case series, four prospective and 14 retrospective cohorts. Overall, there was heterogeneity in reporting as well as limitations in most studies.

CONCLUSIONS

The outcome of endodontic treatment (ET) either nonsurgical or surgical or combination of these is not affected by older age. ET can be the treatment of choice in older patients wiht pulpal/periapical disease. There is no evidence that older age per se affects the outcome of any type of endodontic treatment.

Prevalence of and Factors Associated With Vertical Root Fracture in a Japanese Population: An Observational Study on Teeth With Isolated Periodontal Probing Depth

INTRODUCTION

Previous studies on the prevalence of vertical root fractures (VRFs) were based on extracted teeth, or teeth referred for apical surgery. This study examined teeth with an isolated periodontal probing depth (PD) as an indicator of VRF. The primary aim of this study was to investigate the prevalence of vertical root fracture (VRF) and non-VRF among teeth with an isolated probing depth (PD) ≥ 5 mm. The secondary aim was to assess factors associated with VRF by comparing the teeth with and without VRF in the Japanese population.

METHODS

A total of 288 teeth with an isolated PD ≥ 5 mm were grouped pathologically into 8 groups comprising VRF and non-VRF conditions. A descriptive analysis for age, sex, tooth type, endodontically treated teeth (ETT) versus non-ETT, proximal contacts, PD (depth), PD (broadness and location), restoration type, and presence of a post was performed. Moreover, the associations between these factors and VRFs were investigated using the Chi-square test.

RESULTS

The prevalence of VRF was 32%. Lower first molars were the most common tooth type in both VRF (31.5%) and non-VRF groups (29.7%), while premolars were exclusively frequent in VRF (30.2%) and not frequent in non-VRF (7.8%). Narrow buccolingual PD was common in VRF (78.1%) whereas wide PD was frequent in non-VRF (67.1%). ETT, narrow buccolingual PD, tooth type (premolars), restoration type (crown), and the presence of a post showed significant associations with VRF (P ≤ .001).

CONCLUSIONS

VRFs may be more prevalent in ETT among the Japanese. Careful assessment is necessary to differentiate VRFs from other conditions when the lower first molars show an isolated PD ≥ 5 mm. When an endodontically treated premolar with a post shows a narrow buccolingual PD, the probability of a VRF may be greater than in other tooth types.

The Limitations of Periapical X-ray Assessment in Endodontic Diagnosis-A Systematic Review

Diagnosis is a key aspect in endodontic treatment, in a decade where invasive interventions are misapprehended as social tendency instead of medical necessity. All diagnostic facets should be considered before intending the operative phase. Intraoral endodontic radiology-based diagnosis has been shown to be limited. Periapical X-ray is the most used endodontic imaging, yet it does not provide high accuracy. Traditionally, dentists have been trained to diagnose a cyst by certain aspects (size, shape and appearance); hence, an assumption that teeth are affected by "periapical cyst" were subjected to unnecessary extraction or apicoectomy. The aim of this systematic review is to critically appraise the publications that relate the histological diagnosis of a periapical lesion (considered the gold standard) to intraoral X-ray investigation. Ovid Medline, PubMed, ScienceDirect, Mendeley and Scopus were searched for English-language studies comparing periapical diagnosis obtained by using two techniques (histopathology and X-ray). Sixteen articles were included for the final analysis (qualitative and quantitative evaluation) out of which only two supported the statement that periapical diagnosis can be coherently assessed through periapical imaging. Although there is not enough evidence to deliver a definitive conclusion, there are many publications that refute the diagnosis of a cyst via periapical X-ray.

Risk factors for and clinical presentations indicative of vertical root fracture in endodontically treated teeth - a systematic review and meta-analysis

INTRODUCTION

The aim of this study was to identify specific clinical signs or symptoms and potential risk factors which are most likely associated with the presence of a vertical root fracture (VRF) in endodontically treated teeth (ETT).

METHODS

Electronic databases (MEDLINE via PubMed, EMBASE via Ovid, Scopus, and Web of Science) were searched by two reviewers in October 2022 for clinical studies, in which at least either the clinical presentation or potential risk factors associated with a VRF were assessed. Risk of bias was assessed using the Newcastle-Ottawa scale. Meta-analyses of odds ratios (ORs) were performed separately for several signs or symptoms and risk factors.

RESULTS

Fourteen sources reporting on 2,875 teeth (489 with VRF and 2,388 without VRF) were included in the meta-analyses. Regarding the clinical presentation, the presence of sinus tracts (OR=4.87; 95%-CI: 1.58-15.0), increased periodontal probing depths (OR=13.24; 95%-CI: 5.44-32.22), swelling/abscess (OR=2.86; 95%-CI: 1.74-4.70), and tenderness to percussion (OR=1.74; 95% CI: 1.18-2.61) were significantly associated with the presence of a VRF (P_adj. value<.05). None of the assessed risk factors (sex, type of teeth, tooth location, posts, indirect restoration, apical extension of the root canal filling), were found to be significantly associated with the presence of a VRF (P_adj. value>.05).

CONCLUSIONS

Four clinical presentations were identified to be the most significant signs or symptoms for a VRF in ETT: presence of sinus tracts, increased probing depths, swelling/abscess, tenderness to percussion. None of the assessed risk factors pointed out to be significantly associated with a VRF.

REGISTRATION

CRD42022354108 (PROSPERO).

Incidence of Endodontic Failure Cases in the Department of Conservative Dentistry and Endodontics, DY Patil School of Dentistry, Navi Mumbai

INTRODUCTION

 Endodontic and restorative treatment goal is to restore occlusion and normal function of a tooth and provide stability to the dental arch. Root canal bacterial infection and apical periodontitis profoundly impact the management and outcome of endodontic treatments. The crucial goal of nonsurgical root canal therapy (NSRCT) is the mechanical removal of infected tissues and the chemical killing of bacteria. The present study assessed the outcomes and factors associated with the failure of primary endodontic treatment.

METHODS

 A total of 250 teeth from 219 patients (104 male and 146 female) were examined in the Conservative Dentistry and Endodontics department, who reported symptomatic root canal-treated teeth. Data through clinical examination and radiographic examination was recorded on a proforma designed for the study of each patient regarding endodontic failure.

RESULTS

 According to the type of tooth maximum number of teeth that were reported with failure are the molars (67.6%), followed by premolar (14.0%), incisor (12.8%), and lastly, canines (5.6%). Based on the location of affected teeth, the maximum teeth that presented with failed root canal treatment were from mandibular posteriors (51.2%), followed by maxillary posteriors (31.60%), maxillary anterior (13.2%), mandibular anterior (4.0%).

CONCLUSION

 Endodontic failures were mostly found in underfilled root canals and poorly sealed post-endodontic coronal restoration and strong association with peri-apical radiolucency.

Impact of systemic health on treatment outcomes in endodontics

BACKGROUND

The healing of periapical lesions after root canal treatment (RCT) is not the result of the curative action of the treatment. The process of healing begins with inflammation, and is resolved by the clearance of the immunogen that induces the immune response. Then, the periapical tissue itself carries out the healing of the periapical lesion, by repair or by a combination of repair and regeneration, depending on the host's reparative response working properly. The ultimate objective of RCT is to achieve wound healing by removing the source of bacterial antigens and toxins, allowing chronic inflammatory tissue to become reparative tissue. Some systemic conditions increase the susceptibility of the host to infection or impair the tissue reparative response, maintaining the inflammatory process and periapical bone resorption after RCT. This can cause the failure of RCT and even the need for extraction of the affected tooth.

OBJECTIVE

To analyse the scientific literature on the possible influence of systemic conditions on the treatment outcomes in endodontics, as well as to discuss the biological mechanisms that may be involved.

METHODS

The search was carried out in PubMed, SCOPUS and EMBASE. The inclusion criteria established were original scientific articles reporting data about some systemic condition in relation to treatment outcomes in endodontics, including clinical studies and studies carried out in animal models.

RESULTS

Systemic factors (age, nutrition, stress, hormones, smoking habits), and systemic diseases, such as diabetes, cardiovascular diseases, osteoporosis, HIV infection, inflammatory bowel disease, and others, can influence or interfere in the repair of periapical tissues after RCT.

DISCUSSION

Some of these systemic diseases can alter bone turnover and fibroblast function, preventing or delaying periapical wound healing. Others can alter the microvasculature, reducing nutrients and oxygen supply to periapical tissues. As a result, these systemic conditions can decrease the success rate of RCT and provoke incomplete wound healing (typically granulomatous tissue formation) in the periapical region.

CONCLUSIONS

The results of this narrative review show worse success rate of RCT, with higher percentage of postoperative radiolucent periapical lesions and higher proportion of non-retained teeth (RFT), associated with several systemic conditions, such as smoking habits and diabetes.

Additional Treatment Indicative of an Unfavorable Endodontic Outcome in a Swedish County-A 10-year Observational Study

INTRODUCTION

This study's aim was to calculate the incidence of first additional endodontic treatment or extraction as the result of an unfavorable endodontic outcome following orthograde root canal treatment (RCT) performed by general dental practitioners during a 10-year period and to identify possible predictors for outcomes.

METHODS

A randomized cohort of 280 individuals (and as many teeth) with an orthograde RCT was followed for over 10 years. Dental records were reviewed, and individuals were recalled when data were missing. The following terminal events indicative of unfavorable endodontic treatment outcome were orthograde retreatment, surgical endodontics, and tooth extractions exclusively due to endodontic reasons. Selected variables related to individuals and treatment (pre-, intra-, and postoperative) were harvested to analyze possible associations with the terminal events. Unadjusted survival analysis and Cox regression analysis were performed and P < .05 was considered statistically significant.

RESULTS

Terminal events were registered for 22 teeth/individuals and 17 of these were orthograde retreatments. The cumulative 10-year survival of RCTs was 92.7% (standard error 1.7%), with a higher yearly incidence during the first 2 years. The univariate analysis identified 5 factors associated with the outcome. There were too few events to perform a multivariate analysis.

CONCLUSIONS

The mean incidence of additional treatment indicative of unfavorable endodontic outcome was 0.7% per year during the first 10 years, but the mean incidence was greater during the first 2 years. Five factors were associated with an unfavorable outcome; however, confounders cannot be excluded from the associations.

Retreatment of XP-endo Shaper and R-Endo files in curved root canals

OBJECTIVES

To compare the retreatment efficiency of XP-endo Shaper and R-Endo files in curved root canals using ImageJ software.

METHODS

Forty extracted mandibular first molars with curved mesial canals (25°-35°) were chosen. Access cavities, preparation and obturation of root canals were performed. Roots were randomly distributed into two groups corresponding to the retreatment files used. Group 1 retreated with XP-endo Shaper file, and group 2 retreated with R-Endo files. Each root was sectioned and photographed. ImageJ software was used to estimate the percentage of residual filling material that existed on the three root canal segments. Mann-Whitney U and the Kruskal-Wallis tests were used to compare the percentages of residual filling material between the teeth segments (P < .05).

RESULTS

The R-Endo group showed a significantly higher median percentage of residual filling material than the XP-endo Shaper group. In both groups, the coronal segments had the highest median of the residual filling material, followed by the middle and apical segments.

CONCLUSION

XP-endo Shaper is significantly more effective than R-Endo in removing root canal filling materials in the coronal, middle, and apical segments.

Applications of maxillary tuberosity block autograft

OBJECTIVE

Autogenous bone grafts are considered the gold standard due to their compatibility and osteogenic potential to induce new bone formation through osteogenesis, osteoinduction, and osteoconduction. The aim of this paper was to describe clinical applications of the maxillary tuberosity block autograft in small and moderate localized defects of the alveolar process around implants and teeth.

CLINICAL CONSIDERATIONS

Maxillary tuberosity is often used as a particulate graft for augmentation of deficient alveolar ridge or maxillary sinus prior to or simultaneously with implant insertion, but not as a bone block graft. The maxillary tuberosity block autograft may also provide a valuable bone source for challenging situations such as immediate implant placement into types II and III extraction sockets, treatment of horizontal and vertical bone defects with simultaneous implantation, reconstruction of circumferential defects around implants, and preservation of alveolar ridge.

CONCLUSIONS

The advantages of the maxillary tuberosity include intraoral corticocancellous autogenous graft with fewer intraoperative difficulties, no need for donor site restoration, less morbidity, and an excellent correction of localized alveolar ridge defects.

CLINICAL SIGNIFICANCE

Within the limitations of the presented case reports, the use of maxillary tuberosity block autograft has shown to be successful in alveolar ridges augmentation that lack both width and height.

Quality of life and satisfaction of patients two years after endodontic and dental implant treatments performed by experienced practitioners

OBJECTIVES

To compare oral health related quality of life (OHRQoL) and patients´ satisfaction with root canal treatment (RCT) and dental implant (DI) therapy performed by experienced practitioners.

METHODS

Patients with both an RCT and a DI performed respectively by an endodontist and an oral surgeon with more than 15 years of experience two years prior to the study were included. The survival and satisfactory outcome of both treatments were verified with clinical and radiographic data. Participants completed two constructed questionnaire (one for each treatment). OHRQoL assessment included 24 items (OHIP-14 plus other relevant 10 items from the original OHIP-49 questionnaire). Satisfaction regarding duration, cost and pain (both during and after treatment) of treatment was assessed with a 0-10 scale and perceptions with true/false questions. Weighted sums for each dimension, total OHIP scores, prevalence of impact and general satisfaction of patients were then calculated for DI and RCT and compared using the Wilcoxon test for related samples. Patients´ perceptions were compared with Chi-square test.

RESULTS

Total OHIP scores were low for both treatments (8.82 and 7.87, respectively for RCT and DI). No significant differences were detected in OHIP total score or any dimension, except for physical pain (significantly higher for RCT than DI (p=0.044)). All patients were satisfied with both treatments; however, patients recalled that pain during treatment was significantly worse for RCT than DI (p=0.003).

CONCLUSIONS

High long-term OHRQoL and satisfaction is expected with either DI or RCT performed by experienced practitioners; however, physical pain dimension is higher for RCT.

CLINICAL SIGNIFICANCE

This study demonstrated a high satisfaction and long-term quality of life of patients undergoing both DI and RCT if treatments provide a functional balance and are performed by experienced practitioners. Very importantly, all participants had received both treatment modalities and being their own control eliminates individual variability.

Present status and future directions - Managing perforations

Root perforations are severe complications and are associated with compromised endodontic treatment outcomes, especially when bacterial infection is allowed to establish. Perforations may occur due to pathological processes or treatment consequences. Various dental materials have been proposed over the years for perforation repair with varying degrees of success. The use of bioactive materials, such as mineral trioxide aggregate (MTA) and other calcium-silicate cements, promotes a favourable environment for regeneration and has been used successfully for perforation repair. This is in contrast to materials used previously that often led to unpredictable outcomes. With the increasing range of new bioactive endodontic materials available, the number of potential materials being used for repair of root perforations is growing. Though promising to date, there is little evidence to support the use of most of these new materials. The aim of this narrative review is to provide the background, clinical techniques and outcome of nonsurgical and surgical perforation repair.

Effect of Different Post Materials and Adaptability on Fracture Resistance and Fracture Mode in Human Endodontically Treated Teeth

Objective. To investigate the effect of different post materials and adaptability on fracture resistance and fracture mode of endodontically treated teeth. Materials and Methods. Sixty extracted human mandibular premolars were selected and divided into 6 groups (n = 10) according to the restorative method after endodontic treatment: no ferrule presented and restored without fiber post (Group C), 2.0 mm ferrule presented and restored without fiber post (Group CF), restored with D.T. Light-Post (Group PDT), restored with anatomically customized D.T. Light-Post, relined with resin composite (Group ADT), restored with Hi-Rem prosthetic post (Group PHR), and restored with anatomically customized Hi-Rem prosthetic post, relined with resin composite (Group AHR). After restoring with core build-up materials, all specimens were loaded at 45° in a universal testing machine until failure. Visual inspection of all specimens for fracture modes was performed. The data were analyzed using one-way ANOVA, and the fracture mode was reviewed using the chi-square test. Results. Anatomically customized groups presented statistically significant higher fracture resistance than prefabricated groups and group C ( $P<0.05$ ). Without post, group CF displayed significantly higher fracture resistance than group C ( $P<0.05$ ). Group C, CF, PDT, and PHR showed some specimens with unfavorable fractures. Conclusions. Anatomically customized posts presented highest fracture resistance among all groups. There was no significant difference in fracture mode across all groups.

Restorative difficulty evaluation system of endodontically treated teeth

OBJECTIVE

This article provides an updated overview of restorative procedures of endodontically treated teeth.

CLINICAL CONSIDERATIONS

The different techniques and procedures to restore an endodontic treated tooth were considered in the last decades. While they are generally performed using bonding procedures in combination with or without the placement of a post into the root to build up the abutment, there has been a lack of interest in restorative difficulties that can be faced. Failures are represented such as debonding of the post, fracture of the root, decementation, and/or fracture of the restoration, microleakage of the margins. Essentially, the presence of a sufficient failure is considered a key point of a long prognosis. Different clinical factors can directly influence the type of restoration and the longevity of the treatment. The restorative difficulty evaluation system (RDES) is proposed in this article. This new system is composed of eight different clinical factors that are divided into six levels of difficulties. The RDES is composed of 1. Endodontic complexity and outcome, 2. Vertical amount of coronal residual structure and dimension of the pulp chamber, 3. Horizontal amount of coronal residual structure, 4. Restoration marginal seal, 5. Local interdisciplinary conditions, 6. the complexity of the treatment planning, 7. Functional need, 8. Dental wear and esthetic need.

CONCLUSION

This article reviews the RDES and outlines critical steps and tips for clinical success.

CLINICAL SIGNIFICANCE

The RDES allows to any clinician to evaluate restorative difficulties when an endodontic treated tooth must be restored, combines clinical aspects that can involve from the single tooth to a full mouth rehabilitation.

Effect of an Intraorifice Barrier on Endodontically Treated Teeth: A Systematic Review and Meta-Analysis of In Vitro Studies

The main cause of unsuccess in endodontically treated teeth (ETT) is due to bacterial recontamination. The placement of an intraorifice barrier (IOB) has been proposed for preventing this event in cases that the restoration is in an inadequate condition, enhancing the possibilities for predictable long-term success in endodontic therapy. Objectives. To evaluate through a systematic review and meta-analysis if it would be necessary to place an IOB in ETT. Materials and Methods. The present review is in accordance with the PRISMA 2020 Statement and is registered in the Open Science Framework. Two blinded reviewers carried out a comprehensive search in four databases up to July 10^th, 2021: MEDLINE, Scopus, Embase, and Web of Science. Eligible studies were the ones which evaluated the use of an IOB in ETT in reducing microleakage with any material of choice and with any methods employed. Only in vitro studies published in English were included. Results. A total of thirty in vitro studies were included in the qualitative synthesis, and seven of those were included in the quantitative analyses evaluating the following materials: bioceramic cement, glass-ionomer cement (GIC), and resin-based composite (RBC). Most of the included studies placed an IOB at a 3 mm depth. Reduction in microleakage was observed when an IOB was placed, regardless of the material employed (p ≤ 0.01). Among the materials, GIC and RBC performed similarly (p > 0.05), with the bioceramic subgroup being statistically superior to the GIC subgroup (p ≤ 0.05). Conclusions. Although well-designed randomized clinical trials are required, the placement of an intraorifice barrier can significantly reduce microleakage in endodontically treated teeth, and the use of bioceramics as IOB seems to be the best available material for this purpose.

Periodontal and Periapical Outcomes of Surgical Extrusion: A Prospective Clinical Volumetric Study

INTRODUCTION

Outcome predictors for the restoration of endodontically treated teeth mainly include cavity wall integrity and the presence of a 1.5-2 mm ferrule. However, in some clinical situations, the aforementioned predictors cannot be achieved. Three different techniques have been proposed to obtain an adequate ferrule respecting the supracrestal tissue attachment: surgical crown lengthening, orthodontic forced eruption, and surgical extrusion. There are little published prospective data evaluating periodontal changes after surgical extrusion. Therefore, the aims of this study were to report the outcome of surgical extrusion in single-rooted teeth, to digitally evaluate soft tissue volumetric changes after surgical extrusion, and to observe patient satisfaction regarding the treatment after a minimum of 1 year.

METHODS

This prospective clinical study was performed between 2017 and 2020. Thirteen patients referred for surgical extrusion met the following inclusion criteria: nonsmokers; systemically healthy with at least 1 straight, single-rooted tooth with an insufficient ferrule; a favorable tooth crown-to-root ratio, and no periodontal pathology. Preoperative clinical variables included patient age, sex and phenotype, tooth number, tooth mobility, crown-to-root ratio, gingival index (GI), probing pocket depths at 6 sites, bleeding on probing (BOP), and mesial and distal interproximal papillae volume. Surgical extrusion was performed by a single operator who completed the root canal treatment/retreatment and restored the teeth with a crown. One year later, all patients were controlled, and the following variables were recorded: tooth mobility, crown-to-root ratio, GI, pocket depth, BOP, interproximal papillae aspect, soft tissue rebound, periapical healing, marginal bone loss, and patient-reported outcome measures of the treatment. All variables were analyzed using a descriptive method (mean, %). The Wilcoxon test was used to evaluate pre- and postoperative clinical parameters at a significance level of .05.

RESULTS

At a mean follow-up period of 18.8 months, no teeth were extracted. Compared with preoperative GI and BOP, a significant reduction was observed at 1 year after surgery. Likewise, no significant differences in probing depths were shown, and only 1 tooth presented a type 2 mobility. The mean soft tissue rebound was -0.46 ± 0.69 mm. Overall, no significant interproximal papillae height loss was observed.Apical lesions were completely healed after surgery. The tooth crown-to-root ratio was favorable in all cases before extrusion, whereas in 3 cases it was appropriate (1 = 1), and only 1 case presented >25% of marginal bone loss during the follow-up period. The reported success rate was 92.3%, and patients were generally satisfied with the outcome.

CONCLUSIONS

Surgical extrusion of single-rooted teeth was successful with minimal or no soft tissue loss, and patients were satisfied with the surgical procedure and the esthetic result.

Monolithic Endocrown Vs. Hybrid Intraradicular Post/Core/Crown Restorations for Endodontically Treated Teeth; Cross-sectional Study

The gold standard for restoring Endodontically Treated Teeth (ETT) with successful clinical longevity requires having minimal invasive preparations and maximal tissue conservation. Many dentists still consider hybrid post/core/crown to be the first choice for restoring ETT. Endocrown is a viable alternative treatment modality to hybrid post/core/crown. This study aims to assess the proper judgment of dentists working in Riyadh, Saudi Arabia on the use of monolithic endocrown versus hybrid post/core/crown for restoring ETT. The IRB of Princess Nourah Bint Abdulrahman University (PNU) Institutional Review Board reviewed this study. The questionnaire was validated and electronically distributed. The participants were pre-informed that their responses are completely anonymous and used for professional purposes only. The questionnaire surveyed dentists working in Riyadh, Saudi Arabia, about their preference for different ETT restorative modalities at various clinical scenarios. Data were analyzed using One-way ANOVA and t-test. All P-values of < 0.05 were considered statistically significant. A total of 275 responses were collected; 61.45% were females and 38.55% males. 56% of them were general practitioners, while 16% were consultants. Prefabricated post/core was the most preferred technique among the participants (18.55%), followed by endocrown (12.36%), and lastly, cast post/core (8.73%). The amount of remaining tooth structure was the most influential in the treatment selection (30.18%), followed by the presence or absence of 1–2 mm ferrule (17.82%). Interocclusal space (12.36%) was the least influential factor. Endocrown recorded 63.27% as the most preferred line of treatment in case of insufficient inter-occlusal space. 40.36% preferred endocrown for patients with occlusal risk factors. The amount of the remaining tooth structure and the tooth position significantly affect the treatment options of the participants. Endocrown was the most preferred treatment modality for restoring ETT for patients with occlusal consideration.

Prognostic validity of the Periapical and Endodontic Status Scale for the radiographically assessed 2-year treatment outcomes in teeth with apical periodontitis: a prospective clinical study

Background

Endodontic treatment planning and treatment success evaluation are largely based on radiographic assessment of anatomical and treatment-related parameters of teeth with apical periodontitis (AP). This prospective clinical study aimed to assess radiographically the 2-year endodontic treatment outcomes for teeth with AP, and to evaluate prognostic validity of Periapical and Endodontic Status Scale (PESS).

Methods

A total of 128 patients, representing 176 teeth with AP were examined by cone-beam computed tomography at baseline and at 24 months after endodontic treatment. Treatment outcome was evaluated using estimates of periapical radiolucency and the relationship between anatomical structures and location. The strength of the associations between these and treatment-related parameters was tested by logistic regression analysis. PESS sensitivity and specificity were calculated for every treatment risk group (low, moderate, high) of teeth.

Results

One hundred and fifty-seven teeth, representing 350 root canals had a positive treatment outcome, while 19 teeth, representing 53 root canals had a negative treatment outcome at 24 months. The probability of negative outcome was 25 times higher in the moderate/high-risk group than in the mild-risk group of teeth (OR = 25.1; 95%CI [12.2–51.5]). Pre-treatment complications and retreatment cases with radiolucency were associated with negative outcomes (OR = 35.9; 95%CI [12.6–102.4]; OR = 26.437; 95%CI [10.9–64.1], respectively). PESS sensitivity and specificity was over 80% in all risk groups except for high risk group, due to very low number of cases.

Conclusions

Endodontic treatment outcome depends on the severity of periapical changes. The presence of complications and retreatment cases with periapical lesions are associated with negative treatment outcome. The PESS is a valid instrument to predict outcome of teeth with low-moderate treatment risk of AP.

Prevalence and risk factors of Apical periodontitis in endodontically treated teeth: cross-sectional study in an Adult Moroccan subpopulation

Background

The present study aimed at investigating the prevalence of Apical periodontitis in a Moroccan Adult subpopulation with a non-surgical root canal treatment and to assess associated risk factors including endodontic treatment quality, periodontal health status, coronal restoration cavity design and quality.

Methods

A total of 358 endodontically treated teeth were evaluated after more than 1-year period in a Moroccan subpopulation according to predetermined criteria. Studied parameters were assessed clinically and radiographically. The association between coronal restoration quality, cavity design, periodontal status, root canal filling quality, coronal restoration related features, presence or absence of the opposing dentition and the periapical status was determined. Data were analyzed using chi-square test, odds ratio and logistic regression.

Results

The present study revealed that gingival health, coronal restoration with CL II cavity design, and root canal filling quality influenced periapical status of endodontically treated teeth. Multivariate analysis showed that this association was statistically significant for gingival inflammation (95% CI 1.08–3.91, OR 2.05, p = 0.02), inadequate coronal restoration (95% CI 1.16–4.04, OR 2.16, p = 0.01), inadequate root canal filling length and homogeneity (95% CI 1.24–3.01, OR 1.93, P = 0.004), (95% CI 1.41–4.44, OR 2.50, p = 0.002) respectively.

Conclusions

The present study revealed that inadequate coronal restorations especially with large proximal margins (CL II cavity design) and gingival inflammation increased the risk of apical periodontitis in endodontically treated teeth. Prevalence of Apical periodontitis in the present study was 72.1%.

Histological and Radiological Features of a Four-Phase Injectable Synthetic Bone Graft in Guided Bone Regeneration: A Case Report

BACKGROUND AND OBJECTIVE

Injectable synthetic bone grafts (ISBG) are widely used biomaterials for regeneration purposes. The aim of this case report was to examine the efficacy of ISBG in the management of buccal fenestration in the case of a 25-year-old female.

CASE REPORT

After a traumatic tooth extraction, the defect was filled with ISBG and covered with a resorbable membrane. The ISBG showed easy handling and the patient had no complications during healing. Six months after augmentation, a bone biopsy was taken during implant bed preparation. The histological results showed good integration of ISBG into the newly formed bone and no signs of tissue inflammation. Additionally, a CBCT (cone beam computed tomography) analysis was performed to support the histological results.

CONCLUSION

The use of the examined ISBG led to successful treatment of the buccal fenestration defect.

Long-Term Follow-Up of Nonsurgical Endodontic Treatments Performed by One Specialist: A Retrospective Cohort Study about Tooth Survival and Treatment Success

Background

The main aim of the retrospective cohort study was to evaluate tooth survival after the endodontic treatment over a period of more than 20 years. Moreover, success of the treatment and the correlation between baseline parameters and the outcomes were analyzed, and causes were recorded.

Materials and Methods

Clinical records (including radiographs) of subjects treated with endodontic procedures (both primary and secondary (nonsurgical retreatment)) were collected and analyzed, covering a period of up to 29 years. Type of the treatment, technique, adequacy of treatment performed, presence of baseline radiolucency, and symptoms at baseline were recorded. Moreover, failure (presence of radiolucency 2 years after treatment) and tooth extraction data and causes of them were recorded. Outcomes were explored by using survival analysis (Kaplan-Meier estimates and survival table analysis) and regression analysis (Cox regression).

Results

A total of 2,679 endodontically treated teeth were included in the analysis. After 20 years from the treatment, the cumulative survival rate for primary and secondary treatments was 84.10% (80.99%-87.21%) and 89.79% (86.68%-92.90%), respectively. No differences were found between primary and secondary treatments or with regard to the technique adopted. The presence of periapical radiolucency was correlated to higher odds of tooth extraction.

Conclusions

Despite the limitations of the study, we can assume that the proportion of retained endodontically treated teeth was significantly high over a long-term period.

Comparing endocrown restorations on permanent molars and premolars: a systematic review and meta-analysis

Objectives The objective of this systematic review was to evaluate the success of endocrown restorations on molars in comparison with endocrown restorations on premolars.Registration number The methodology for this review is registered with the PROSPERO database (CRD42019149543).Data sources Medline, Embase, Dentistry & Oral Sciences Source and Cochrane CENTRAL were searched through January 2020, supplemented with hand searching of additional relevant journals.Data selection and data extraction Two independent reviewers screened studies against predefined inclusion criteria and extracted data.Data analysis Narrative analysis was carried out and random-effects meta-analysis was performed where possible.Results Out of the selected eight studies, reported success rate of endocrown restoration in molars varied from 72.73% to 99.57% and in premolars ranged from 68.75% to 100%, with a follow-up range of 3-19 years. The pooled odds ratio and 95% confidence intervals for failure rates in molars compared to premolars in four studies selected for meta-analysis were 1.096 (95% CI: 0.280, 4.292).Conclusions These findings showed similar success rates and no difference in the rate of endocrown failures between molars and premolars, thus suggesting that premolars may be considered suitable candidates for endocrowns. However, the findings should be interpreted with caution due to methodological limitations of the included studies. Further better quality and specifically designed controlled trials directly comparing the clinical performance of endocrowns on molars and premolars are required.

Smoking and Radiolucent Periapical Lesions in Root Filled Teeth: Systematic Review and Meta-Analysis

Aim: This systematic review and meta-analysis aimed to investigate the association between smoking habits and the prevalence of radiolucent periapical lesions (RPLs) in root-filled teeth (RFT). Methods: The Population, Intervention, Comparison, and Outcome (PICO) question was: in adult patients who have RFT, does the absence or presence of a smoking habit affect the prevalence of RPLs associated with RFT? Systematic MEDLINE/PubMed, Wiley Online Database, Web of Science, Scopus, and PRISMA protocol were used to evaluate and present the results. Studies comparing smokers with control non-smoker subjects, including RFT, and providing data on the prevalence of RFT with RPLs, were included. The Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system was used for certainty in the evidence. The risk of bias was assessed according to Cochrane Collaboration common scheme for bias and ROBINS-I tool. Cumulative meta-analysis was performed with a random effects model. PROSPERO registration code: CRD42020165279. Results: Four studies reported data on inclusion criteria, representing data from 9257 root-filled teeth—4465 from non-smokers and 4792 from smoker patients. The meta-analysis provided an odds ratio indicating a significant association between smoking and higher prevalence of root filled teeth with radiolucent periapical lesions (OR = 1.16; 95% CI = 1.07–1.26; p = 0.0004). The certainty of the literature assessment was moderate per GRADE. The ROBINS-I tool classified three studies as low risk of bias, and the fourth as moderate risk of bias. Conclusions: Moderate, quality scientific evidence indicates a weak but significant relationship between smoking and the prevalence of RPLs in RFT. Smoking can be considered a negative prognostic factor for the outcome of root canal treatment. Endodontic providers should be aware of the relationship between smoking and persistent apical periodontitis, assessed as RPLs, in RFT.

Cigarette Smoking and Root Filled Teeth Extraction: Systematic Review and Meta-Analysis

Aim: The aim of this systematic review and meta-analysis was to investigate the possible association between smoking habits and the occurrence of root-filled teeth (RFT) extraction. Material and Methods: The Population, Intervention, Comparison, and Outcome (PICO) question was in adult patients who had RFT, does the absence or presence of smoking habits affect the prevalence of extracted RFT? Systematic MEDLINE/PubMed, Wiley Online Database, Web of Science, and PRISMA protocol was used to evaluate and present the results. The Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system was used for certainty in the evidence. The risk of bias was assessed according to Cochrane Collaboration common scheme for bias and ROBINS-I tool. Cumulative meta-analysis was performed with a random effects model. PROSPERO registration code: CRD42020165279. Results: After search strategy, 571 articles were recovered, seven were selected for full-text analysis, and two reported data on inclusion criteria, including 516 RFT, 351 in non-smokers, and 165 in smoker subjects. The meta-analysis provided an odds ratio indicating significant association between smoking and the prevalence of extracted RFT (OR = 3.43, 95% CI = 1.17–10.05, p = 0.02, I² = 64%). The certainty of the literature assessment was low per GRADE. Both studies were considered as moderate risk of bias. Conclusions: Tobacco smoking should be considered a negative prognostic factor for the outcome of root canal treatment, although the quality of the evidence is low. RFT of smoking patients are three times more likely to be extracted. Continuing to smoke after endodontic treatment may increase the risk of treatment failure. However, the overall strength of evidence is low. This must be considered a limitation of the present study and the conclusion should be valued with caution.

Endodontic Periapical Lesion: An Overview on the Etiology, Diagnosis and Current Treatment Modalities

Nonsurgical and surgical endodontic treatments have a high success rate in the treatment and prevention of apical periodontitis when carried out according to standard and accepted clinical principles. Nevertheless, endodontic periapical lesions remain in some cases, and further treatment should be considered when apical periodontitis persists. Although several treatment modalities have been proposed for endodontically treated teeth with persistent apical periodontitis, there is a need for less invasive methods with more predictable outcomes. The advantages and shortcomings of existing approaches for the diagnosis and treatment of endodontic periradicular lesions are discussed in this review.

Effect of Ultrasonic Activation of Endodontic Sealers on Intratubular Penetration and Bond Strength to Root Dentin

INTRODUCTION

This study aimed to evaluate the effect of ultrasonic activation (UA) of endodontic sealers on dentin tubule penetration and the bond strength to root dentin.

METHOD

One hundred single-rooted teeth were prepared with 40.06 nickel-titanium instruments and divided into 2 groups: with or without UA. Three resin-based sealers (MTA Fillapex [Angelus Dental Solutions, Londrina, PR, Brazil], Sealer Plus [MK Life Medical and Dental Products, Porto Alegre, RS, Brazil], and AH Plus [Dentsply, DeTrey GmbH, Konstanz, Germany]; n = 20) and 2 calcium silicate-based sealers (Sealer Plus BC [MK Life Medical and Dental Products] and EndoSequence BC [Brasseler, Savannah, GA], n = 20) were used and subdivided (n = 10) according to the protocols. Fluo-3 (Thermo Fisher Scientific, Waltham, MA) and rhodamine B dyes were added to the calcium silicate- and resin-based sealers, respectively. In the UA groups, the activation was performed for 40 seconds followed by lateral compaction. Samples were transversely sectioned to evaluate the dentin tubule penetration and the bond strength to root dentin. The penetration data were analyzed with the Student t test, 1-factor analysis of variance, and Bonferroni tests. Bond strength was evaluated using the Student t test, Kruskal-Wallis, and Dunn post hoc test.

RESULTS

Resin-based sealers showed the highest tubule penetration without UA (P < .05). UA significantly enhanced MTA Fillapex and Endosequence BC dentin tubule penetration (P < .05). AH Plus and Sealer Plus BC improved their bond strength to root dentin after UA (P < .05). AH Plus/UA, Sealer Plus/UA, and Sealer Plus BC/UA presented the highest bond strength values (P < .05). Adhesive failures were predominant in all groups regardless of the use of ultrasound.

CONCLUSIONS

UA interferes with tubule penetration and the bond strength to root dentin of resin- and calcium silicate-based sealers.

Management of Discolored Failure Root Canal-Treated Upper Lateral Incisor

Root canal treatment failure can be determined based on a patient’s complaint and on the basis of clinical examination and radiographic findings. Most of the signs and symptoms for the failure are pain and discomfort, swelling and sinus formation at the surrounding soft tissue, and discoloration of the subjected tooth. Factors such as mechanical perforation during the procedures, overfilled or underfilled root canal, and missed or unfilled canals are the main factors for the failure outcome. This case report presents a discolored and infected upper lateral incisor which was previously root canal treated. The tooth was successfully managed under nonsurgical and surgical retreatment followed by an internal bleaching and full porcelain veneer. Apical tissue healing and acceptable tooth appearance was observed during a 12-month review.

Accidental perforations during root canal treatment: an 8-year nationwide perspective on healthcare malpractice claims

OBJECTIVES

To assess occurrence and its variation over time of serious accidental perforations during endodontic treatment and the fate of perforated teeth by tooth type and characteristics of patients and dentists.

MATERIALS AND METHODS

Data, based on patient documents on healthcare malpractice claims, comprised all endodontic injuries (n = 970) verified by the Patient Insurance Centre in Finland in 2002-2006 and 2011-2013. Two specialists in endodontics scrutinized the documents. Accidental perforations were recorded by location (tooth type, chamber/canals) and dichotomized as avoidable (could have been avoided by following good clinical practice) or unavoidable (normal treatment-related risks). Fate of perforation cases was recorded as treatment discontinued, root canal(s) filled, or tooth extracted. Background information included patients' and dentists' sex and age and the service sector. Statistical evaluation used Chi-square tests.

RESULTS

Serious accidental perforations comprised 29% of all verified injuries. Most perforations were judged as avoidable: 93% in patients aged below 35 years, 87% when located in the pulp chamber or in molars (84%); 70% of all perforations and 75% of those in molars resulted in tooth extraction. The overall rate of serious accidental perforations was 17.6 cases per 100,000 endodontic patients per year.

CONCLUSIONS

The rate of serious accidental perforations increased over time. The majority was in molars and resulted in tooth extraction.

CLINICAL RELEVANCE

Accidental perforations comprise almost a third of serious injuries during root canal treatment. However, four of five perforations could be avoided by following good clinical practice. Therefore, training is needed before adopting new working equipment and methods.

Endodontic sealers and post-endodontic waiting time affect the bond strength of the fiber posts

Abstract Introduction The resistance adhesive of a fiber post can be affected by several factors, such as the endodontic sealer and post-endodontic waiting time. Objective The aim of this study was to evaluate the effect of different endodontic sealers and two different post-endodontic waiting times on the bond strength of fiber posts. Material and method Seventy-two bovine teeth were endodontically treated and filled using three endodontic sealers: eugenol-based, epoxy resin-based, or mineral trioxide aggregate-based. The specimens were stored at 37°C for 24 hours or for 30 months. After the respective storage times, the root canals were prepared for luting fiber posts using RelyX U200. Push-out tests and analysis of failures were performed. The push-out data were analyzed by two-way analysis of variance to compare the effects of the endodontic sealer and with the t-test to compare the effects of post-endodontic waiting time. Result The AH Plus sealer yielded the highest bond strength values at 30 months post-endodontics (11.26 Mpa) (p < 0.05), however no had difference with Endofill sealer at the same time. Endofill and MTA Fillapex sealers did not differ significantly in their effects, irrespective of the post-endodontic waiting time. Conclusion In conclusion, the endodontic sealer used and post-endodontic waiting time affect the adhesive resistance of fiber posts. The adhesion increases significantly when the fiber post is cemented 30 months after the root canal filling, while the adhesion is reduced when cementing immediately after root canal treatment, in particular for eugenol-based endodontic sealers.

Assessment of extracting molars and premolars after root canal treatment: A retrospective study

Background

The loss of dentition after root canal treatment is a multifactorial entity which might differ between different teeth. The extraction can be more critical, as well as the rehabilitation options.

Aim

To analyze if the etiology of extracting root canal treated teeth is different between premolars and molars.

Materials and methods

The study included a total of 403 cases with non-surgical root canal therapy (NSRCT) and crown coverage that was referred to the oral surgery clinic for extraction. Tooth type, patient’s age, gender, time since treatment completion, and the reason for extractions were recorded and analyzed.

Results

The most frequently extracted teeth were molars (55.6%), followed by premolars (30.3%) and anterior teeth (14.1%). The reasons for extraction were subgingival decay (SGD) (62.5%), vertical root fractures (VRF) (25.3%), and patient demands after uncomfortableabscess discharge (12.2%). Most of the teeth survived between 13 and 36 months after NSRCT. The statistical power of 0.92 was demonstrated, and a P-value of less than 0.05 presented significant correlations.

Conclusion

Molars were extractedafter NSRCT due to SGD followed by premolars, which were extracted due to VRF. Special care should be taken while planning NSRCT treatment for molars, in particular, with emphasis on the importance of oral hygiene and follow-up visits.

Comparison of the Effect for Fracture Resistance of Different Coronally Extended Post Length with Two Different Post Materials

Aims and Objectives:

To compare the effect for fracture resistance of different coronally extended post length with two different post materials.

Materials and Methods:

One hundred and sixty endodontically treated maxillary central incisors embedded in acrylic resin with decoronated root portion were taken for the study. The postspaces were prepared according to standard protocol. The samples were divided into two groups according to the post material: glass-fiber post and Quartz fiber post. These groups were further subdivided on the basis of coronal extension of 4 and 6 mm for glass fiber and Quartz fiber posts, respectively. The posts were then luted with dual-polymerizing resin cement followed by core buildup. Samples were subjected to increasing compressive oblique load until fracture occurred in a universal testing machine. Data were analyzed with one-way ANOVA and independent Student's t-test. Analysis was done using SPSS version 15 (SPSS Inc., Chicago, IL, USA) Windows software program.

Results:

Glass fiber post with coronal extension of 4 mm (182.8 N) showed better results than with 6-mm length (124.1 N). Similarly, in quartz fiber posts group, 4-mm postlength (314 N) was better when compared with 6 mm (160 N). The 4-mm coronal extension of quartz fiber post displayed superior fracture resistance.

Conclusions:

Glass fiber posts showed better fracture resistance than Quartz fiber posts. 4-mm coronal length showed more fracture resistance than 6 mm.

The Effect of Crown Lengthening on the Outcome of Endodontically Treated Posterior Teeth: 10-year Survival Analysis

INTRODUCTION

The purpose of this study was to investigate the effect of a crown lengthening (CL) procedure and the crown-root ratio after CL on the long-term survival of endodontically treated teeth (ETT).

METHODS

Permanent posterior teeth with opposing dentition that had received adequate nonsurgical root canal treatment (NSRCT) and a full-coverage crown between January 1, 2006, and January 1, 2016 were included in this retrospective study. The data collected included dates of the NSRCT, time of extraction if extracted, age, sex, location, the crown-root ratio after CL, and the presence of a lesion. All included ETT were divided into 2 groups: RESULTS: 5-year survival rates of ETT in the control and CL groups were 88.6% and 82.2%, respectively (P > .05). The 10-year survival rates of ETT in the control and CL groups were 74.5% and 51%, respectively (P < .05). ETT that received the CL procedure after NSRCT were almost 2.3 times more likely to get extracted compared with ETT that did not need the CL procedure at the 10-year follow-up (hazard ratio = 2.29, P < .05). Also, ETT with an inadequate crown-root ratio (1:1) after CL showed the lowest survival rate (40%) compared with ETT with an adequate crown-root ratio (<1:1).

CONCLUSIONS

A crown-root ratio of 1:1 after osseous CL may affect the long-term survival of ETT. Despite the promising survival rate of ETT with an adequate crown-root ratio after CL, the long-term survival of NSRCT with an inadequate crown-root ratio (1:1) should be considered in the treatment planning phase. Also, it is worth mentioning that the results of the present study should be evaluated in future prospective studies.

Evaluation of Two Shaping Systems and Two Ultrasonic Irrigation Devices in Removing Root Canal Filling Material from Mesial Roots of Mandibular Molars: A Micro CT Study

We assessed the efficiency of two shaping file systems and two passive ultrasonic irrigation (PUI) devices for removing filling material during retreatment. The mesial canals from 44 extracted mandibular molars were prepared and obturated. The teeth were randomly divided into two groups, and then one group was retreated with Reciproc R25 (VDW, Munich, Germany) (n = 44) and the other group was retreated with 2Shape (TS, Micro Mega, Besançon, France) (n = 44). A micro-computed tomography (CT) scan was taken before and after the retreatment to assess the volume of the filling material remnants. The teeth were then randomly divided into four groups to test two different PUI devices: Irrisafe (Satelec Acteon Group, Merignac, France) and Endo Ultra (Vista Dental Products, Racine, WI, USA). The teeth in Group A were retreated with 2Shape to test the Endo Ultra (n = 22) device, the teeth in Group B were retreated with 2Shape in order to test the Irrisafe (n = 22) device, the teeth in Group C were retreated with Reciproc to test the Endo Ultra (n = 22) device, and Group D was retreated with Reciproc to test the Irrisafe (n = 22) device. A third micro-CT scan was taken after the retreatment to test the PUIs. The percentage of Gutta-Percha (GP) and sealer removed was 94.75% for TS2 (p < 0.001) and 89.3% for R25 (p < 0.001). The PUI significantly enhanced the removal of the filling material by 0.76% for Group A (p < 0.001), 1.47% for Group B (p < 0.001), 2.61% for Group C (p < 0.001), and by 1.66% for Group D (p < 0.001). 2Shape was more effective at removing the GP and sealer during retreatment (p = 0.018). The supplementary approach with PUI significantly improved filling material removal, with no statistical difference between the four groups (p = 0.106).

The Effect of Intraradicular Multiple Fiber and Cast Posts on the Fracture Resistance of Endodontically Treated Teeth with Wide Root Canals

Introduction

The endodontically treated teeth (ETT) with thin remaining radicular dentin thickness are predisposed to fracture; hence it requires the diligent selection and the execution of endodontic post treatment. The objective of the study was to evaluate the reinforcing effect of both multiple fiber reinforced composite (FRC) and Ni-Cr cast metal posts at anterior and posterior regions.

Material and Methods

Forty recently extracted root canal treated canine and single rooted premolar teeth were used for the study. They were randomly divided into four groups (n=10) as: Group 1, single FRC post; Group 2, multiple FRC posts; Group 3, single Ni-Cr metal post, Group 4, multiple Ni-Cr posts. The posts were cemented with self-adhesive resin cement and subsequently restored with full veneer metal crown. The compressive static load at 130⁰ for canine and 45⁰ for premolar was applied with the cross-head speed of 0.5mm/minute until the fracture. The obtained data was analyzed using the Kruskal–Wallis and Pairwise comparison tests with SPSS.

Results

The results indicate that multiple FRC post restored canine had the maximum fracture load (1843.80±7.13 N), followed by cast multiple posts (1648.99±26.84 N), single fiber post (1623±40.31 N), and cast metal single post (1493±27.33 N). A similar trend was observed in premolar with higher max fracture load with multiple FRC posts at 1920.86±20.61 N and multiple cast metal posts at 1735.43±6.05 N.

Conclusion

The restoration of ETT with larger canals by multiple FRC and metal posts provides substantially higher fracture resistance in comparison to wider single post.