Changes in periapical status, quality of root fillings and estimated endodontic treatment need in a similar urban German population 20 years later

Analysis of Pediatric Pulpotomy, Pulpectomy, and Extractions in Primary Teeth Revealed No Significant Association with Subsequent Root Canal Therapy and Extractions in Permanent Teeth: A Retrospective Study

Recent evidence suggests that an ever-growing number of pediatric patients require invasive treatments such as root canal therapy (RCT) in their permanent dentition, albeit with little information about risk factors such as prior invasive treatments of pulpotomy or pulpectomy in their primary dentition. Therefore, the primary objectives of this study were to determine the number of pediatric patients who have had any type of invasive treatment in their primary teeth, to assess their association with any subsequent invasive treatment (root canal therapy, extractions) in their permanent dentition, and to assess these trends over time. This retrospective study utilized summary data from a clinical pediatric patient pool (ages 0-17) over the period of 2013-2022. This analysis revealed that pediatric patients requiring pulpotomies and pulpectomies in primary dentition declined between 2013 (n = 417, n = 156) and 2022 (n = 250, n = 12), while root canal therapy (RCT) in permanent dentition increased six-fold from n = 54 to n = 330. In addition, few (7.8%) patients with RCT had a previous history of pulpotomy or pulpectomy, which suggests that invasive treatments performed in primary dentition have no direct association with the subsequent need for invasive treatments in permanent dentition, although more research is needed to determine the explanations for these observations.

A 22-year follow-up cross-sectional study on periapical health in relation to the quality of root canal treatment in a Belgian population

AIM

To investigate the prevalence of apical periodontitis (AP) and the technical standard of root canal treatment in a Belgian population, assess the association of different variables with periapical status, and compare the results to a similar study conducted 22 years previously.

METHODOLOGY

In this cross-sectional study, 614 panoramic radiographs of first-time adult attendees at the Dental School of the University Hospital of Ghent were examined. Recorded patient-level parameters included gender, age, number of teeth, number of root filled teeth, presence of any AP lesion, and number of implants. The following tooth-level data were collected: tooth presence, coronal status, quality of coronal restoration, post presence, type of root-filling material, length and density of root filling, root-end filling material, presence of AP, and adjacent implant. Multivariable multilevel binary logistic regression was used to explore the association between patient and tooth characteristics and AP prevalence. Risk differences and confidence intervals were calculated to compare the present with the previous study.

RESULTS

The prevalence of AP at patient and tooth level was 46.9% and 5.6%, respectively. Fifty-one per cent of the 614 patients had at least one root filled tooth, and 5.9% of the 14 655 teeth studied were root filled. AP was found in 45% of root filled teeth. Fifty-four per cent of the root-filled teeth were rated as inadequate. Multivariable multilevel logistic regression revealed that more teeth, more implants, fewer root-filled teeth, adequate density, adequate coronal restoration, and no caries reduced the likelihood of AP. There were no statistically significant differences between the two studies regarding the prevalence of root-filled teeth or AP and the technical quality of root canal treatment.

CONCLUSIONS

The prevalence of AP and the technical quality of root canal treatment in Belgium have not substantially changed over the last 22 years, despite the technological advancements and continuing education in the field.

Effectiveness of root canal instrumentation for the treatment of apical periodontitis: A systematic review and meta-analysis

BACKGROUND

The development of endodontic instruments has rapidly advanced, but their impact on endodontic outcome parameters remains unclear.

OBJECTIVES

This systematic review aimed to answer the following PICOT questions: In patients with apical periodontitis (P) what is the effectiveness of root canal instrumentation ([Q1] performed with contemporary techniques [I] in comparison with 'traditional' techniques [C]] and ([Q2] performed with contemporary engine-driven NiTi instruments [I] compared with other types of contemporary engine-driven NiTi instruments [with different design and/or technology] [C]) in terms of clinical and patient-related outcomes (O)?

METHODS

After PROSPERO protocol registration, a literature search was conducted using Clarivate Analytics' Web of Science, Scopus, PubMed and Cochrane Central Register of Controlled Trials. Grey literature and major journal contents were examined. Two independent reviewers performed the study selection, data extraction and appraisal of included studies. A quantitative meta-analysis was considered, and statistical heterogeneity and overall quality of evidence were assessed.

RESULTS

Nine studies were identified showing substantial methodological differences. Five studies addressed PICOT 1 and three PICOT 2, whereas one study aimed both. A random-effects meta-analysis model was considered for the outcome 'radiographic evidence of normal periodontal ligament space or reduction of apical lesion size' (PICOT 1) based on three studies with 332 evaluable participants and showed that contemporary instrumentation was associated with a more favourable outcome (p = .005) compared with root canal preparation with stainless steel instruments (odds ratio = 2.07 [95%-confidence interval = 1.25-3.44]) with no evidence of statistical heterogeneity (I2  = 0%) but low quality of evidence.

DISCUSSION

Albeit a few studies fulfilled eligible criteria, no study had a low risk of bias. Compelling evidence indicating significantly different outcome rates using different endodontic instruments when treating teeth with apical periodontitis is lacking.

CONCLUSIONS

In terms of healing, the results of the meta-analysis determined the higher effectiveness of root canal instrumentation performed with contemporary techniques in comparison with conventional stainless steel instruments in patients with apical periodontitis followed for a minimum of 1 year with low quality of evidence. No differences could be demonstrated between preparations with traditional stainless steel and contemporary NiTi instruments for other clinical and patient-related outcomes.

REGISTRATION

PROSPERO (CRD42021274642).

Endodontic Outcome of Root Canal Treatment Using Different Obturation Techniques: A Clinical Study

OBJECTIVE

To evaluate the clinical outcome of root canal treatment by obturation technique, root canal filling quality, and tooth- and patient-related variables.

METHODS

This clinical study investigated the endodontic outcome of 114 teeth treated between the years 2009 and 2012. Three different obturation methods were used: (1) adhesive obturation using the continuous wave of condensation technique with Resilon® (CWR), (2) matching-taper single-cone technique with gutta-percha and AH Plus® (SCGP), and (3) matching-taper single-cone technique with gutta-percha and GuttaFlow® (SCGF). Pre- and postoperative periapical radiographs were performed to detect the presence of endodontic lesions (PAI classification) and to assess the quality of both the obturation and the restoration. Tooth- and patient-related data were collected.

RESULTS

The overall endodontic success rate was 75.4% after a mean observation period of 6.3 years. There were no significant correlations between the type or overall quality of obturation and the treatment outcome. Teeth with preoperative lesions had the highest odds ratio (factor of 4.98) for endodontic failure. Tooth- and patient-related variables had no significant effect on endodontic outcome.

CONCLUSIONS

The preoperative periapical status of teeth requiring endodontic treatment was a substantial prognostic factor for endodontic outcome, whereas the type of obturation material or technique did not affect it.

Periapical status and technical quality in root canal filled teeth in a cross sectional study in Jönköping, Sweden

OBJECTIVE

To investigate the quality of root canal fillings and frequency of apical periodontitis (AP) in root canal filled teeth in a Swedish population.

MATERIAL AND METHODS

This study used data from a cross-sectional survey conducted in 2013. The root canal filling quality and periapical status were assessed in 491 root canal filled teeth in 196 individuals aged 20-70 years, randomly selected from the population of Jönköping, Sweden. All root canal filled teeth were examined with periapical radiographs. Three calibrated observers recorded length and density in root canal fillings as well as periapical status according to the Periapical Index. A root filling ending within 0.5-2 mm from the radiographic apex without lateral or apical voids was considered adequate. Data were analyzed in a generalized estimating equation (GEE) model with AP as dependent variable and gender, age, number of teeth, number of root filled teeth, tooth type, and root filling quality as independent variables.

RESULTS

Teeth with technically inadequate root fillings were associated with AP in a simple GEE-analysis. In the multiple GEE-model, the association between technical quality and apical peridontitis was nonsignificant when controlling for tooth type and gender.

CONCLUSIONS

The quality of root canal fillings is poor and the prevalence of AP in root canal filled teeth is high, particularly in molar teeth, in a Swedish population.

Prevalence of Periapical Radiolucency and Conventional Root Canal Treatment in Adults: A Systematic Review of Cross-Sectional Studies

Cross-sectional studies assess a population's health state and the prevalence of diseases or treatments. Few systematic reviews regarding the prevalence of periapical radiolucency (PARL) and nonsurgical root canal treatment (NSRCT) were conducted in the last decade. The goal of this study was to collect and review all updated and available cross-sectional studies that focus on the prevalence of both PARL and NSRCT in adult populations. It involves a systematic literature review of cross-sectional studies on the prevalence of PARL and NSRCT published from 1987 to 2022 in PubMed, Google Scholar, Web of Science, and Scopus with specific keywords used in the search process. A total of 52 articles were included in this systematic review. The majority of the included articles were from different populations. The overall prevalence of teeth with PARL was 43,522 (6.40%), while the prevalence of NSRCT teeth was 52,149 (7.67%). On the other hand, the overall prevalence of PARL in teeth that have received endodontic treatment and teeth that have not received endodontic treatment were 22,110 (3.25%) and 21,412 (3.15%), respectively. A meta-analysis was not performed due to underreporting of publication bias and the high degree of heterogeneity between studies. The overall risk of bias assessment revealed a low risk of bias in 25 (48%) of the included studies. The prevalence of NSRCT was higher at 7.67%, followed by PARL at approximately 6.40%. However, future studies are recommended to investigate the prevalence of both PARL and NSRCT in different patient populations.

Prevalence of root canal treatment worldwide: A systematic review and meta-analysis

BACKGROUND

The prevalence of root filled teeth (RFT) worldwide will inform about the amount of clinical activity of dentists dedicated to treat endodontic disease.

OBJECTIVES

To carry out a systematic review with meta-analysis answering the following question: What is the prevalence of RFT around the world? The percentage of people with at least one RFT was also investigated.

METHODS

A systematic review including population-based studies using the following databases: PubMed, EMBASE and Scielo. Studies related to prevalence of RFT were included. The outcome of interest of the study was the prevalence of RFT. The meta-analyses were calculated with the Open Meta Analyst software to determine the global prevalence of RFT. Subgroups analyses were performed comparing geographical distribution, radiographic method and year of the study (classified in 20th or 21th century). The prevalence of people with at least one RFT was also analysed.

RESULTS

Seventy-four population-based studies fulfilled the inclusion criteria. Twenty-eight, forty-four and two studies reported high, moderate and low risk of bias, respectively. No obvious publication bias was observed. Prevalence of RFT was estimated with 1 201 255 teeth and 32 162 patients. The calculated worldwide prevalence of RFT was 8.2% (95% CI = 7.3%-9.1%; p < .001). The global prevalence of people with at least one RFT was 55.7% (95% CI = 49.6%-61.8%; p < .001). In 20th century, the prevalence of RFT was 10.2% (95% CI = 7.9%-12.5%; p < .001), whereas in the 21st century the overall calculated prevalence of RFT was 7.5% (95% CI = 6.5%-8.6%; p < .001). Brazilian people (12%) and the European population (9.3%) showed the highest prevalence of RFT. In Europe, 59.6% (95% CI = 52.4%-66.8%) of people has at least one RFT.

CONCLUSIONS

This review showed that root canal treatment is a very common therapy throughout the world. More than half of the studied population have at least one RFT. A limitation of the present study is that most of the studies did not consider random sampling for population selection.

REGISTRATION

PROSPERO Systematic review registration number: (CRD42022329053).

Periapical and endodontic status among 65-year-old Oslo-citizens

Aim

This cross-sectional study aimed to investigate the prevalence of apical periodontitis (AP) and root-filled teeth in a 65-year-old population in Oslo, Norway, and to investigate associations of pathosis and endodontic treatment with selected individual risk indicators and technical quality of root fillings.

Material and methods

A random sample of 450 65-year-olds in Oslo answered a questionnaire and underwent a clinical and radiological examination (52% men and 48% women). Periapical radiographs were taken of all root-filled teeth and of teeth with apical radiolucency, and periapical status was evaluated using the Periapical Index. Apex-to-filling distance and homogeneity were assessed for all root fillings. Analyses on individual level and tooth level were performed. The outcome variables were ‘non-root-filled tooth with AP’ (‘untreated AP’), ‘root-filled tooth’, and 'root-filled tooth with AP’. The explanatory variables were gender, education, dental attendance pattern, smoking, remaining teeth (n), tooth group, and root filling quality. Chi-square test and logistic regression analyses were used to assess the associations between outcome variables and explanatory variables. The level of significance was set to p < 0.05.

Results

The mean number of remaining teeth was 26 (SD: 4). AP was present in 45% of the individuals. Sixteen percent of the individuals had untreated AP and 38% had at least one root-filled tooth with AP. Sixty-six percent of the individuals had one or more root-filled teeth. Untreated AP was significantly associated with a decreasing number of remaining teeth and smoking. All the outcome variables were significantly more prevalent in molars compared with premolars and anterior teeth. Thirty-five percent of the root-filled teeth had AP, and AP was more prevalent in teeth with too short apex-to-filling distance (53%) or unsatisfactory homogeneity (46%).

Conclusions

The remaining number of teeth was high, and AP and root-filled teeth were prevalent in the present young-elderly population. A notable amount of untreated AP was observed, especially in smokers. The findings in the present study indicate a substantial need for dental care associated with endodontic conditions in the future elderly.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12903-022-02406-9.

Apical status and prevalence of endodontic treated teeth among Saudi adults in Eastern province: A prospective radiographic evaluation

Introduction

The main cause for developing periapical lesions (PA) is the root canal infection. The mentioned causes may play a role in not controlling it but are not a “true” cause.

Objective

To determine apical status and prevalence of endodontic treated tooth using radiograph assessment in relation to quality of root canal treatment and clinical factors among Saudi adults in the Eastern province.

Patients and methods

This prospective case series study included 2161 patients who received root canal treatment (RCT) at Dammam Specialized Dental Center, Dammam Medical Complex, Ministry of Health, Saudi Arabia, between October 21, 2019 and April 22, 2020, after getting ethical approval from the Institutional Research Board (IRB). Saudi natives of either gender, age ≥ 18, with at least one fixed bridge or single dental crown evaluated on a clear, high-quality radiography image were recruited for the study. To determine the periapical state of root canal-filled teeth, the 'periapical index' (PAI) was used. All pertinent patient information was analyzed in SPSS verion-20 (IBM product, Chicago).

Results

Out of 2161 cases, a PA lesion was present in 756 (35.0%). The prevalence of periapical lesions in endodontically treated teeth was 31.2%. PA lesion was associated with molar involvement (50.8% vs. 36.6%, p = 0.001), poor RCT quality (85.2% vs. 51.0%, p = 0.001), and smoking (13.6% vs. 10.5%, p = 0.028). According to logistic regression model, female gender, molar tooth, and poor RCT quality were more likely to expose PA lesion 1.5 times, 1.8 times, and 5 times, respectively.

Conclusion

It is concluded that approximately 1/3rd of endodontically treated teeth are susceptible to the occurrence of periapical lesions in radiographic assessment, which are significantly associated with females, molars, and poor RCT quality, indicating a challenge for endodontists to improve their root canal assessment accuracy.

A U-Net Approach to Apical Lesion Segmentation on Panoramic Radiographs

The purpose of the paper was the assessment of the success of an artificial intelligence (AI) algorithm formed on a deep-convolutional neural network (D-CNN) model for the segmentation of apical lesions on dental panoramic radiographs. A total of 470 anonymized panoramic radiographs were used to progress the D-CNN AI model based on the U-Net algorithm (CranioCatch, Eskisehir, Turkey) for the segmentation of apical lesions. The radiographs were obtained from the Radiology Archive of the Department of Oral and Maxillofacial Radiology of the Faculty of Dentistry of Eskisehir Osmangazi University. A U-Net implemented with PyTorch model (version 1.4.0) was used for the segmentation of apical lesions. In the test data set, the AI model segmented 63 periapical lesions on 47 panoramic radiographs. The sensitivity, precision, and F1-score for segmentation of periapical lesions at 70% IoU values were 0.92, 0.84, and 0.88, respectively. AI systems have the potential to overcome clinical problems. AI may facilitate the assessment of periapical pathology based on panoramic radiographs.

Tooth- and Patient-Related Conditions May Influence Root Canal Treatment Indication

Aim

To investigate predisposing aspects related to the indication for root canal treatment (RCT) at Dental Schools of Brazil.

Methods

Data of 207 patients referred to endodontic treatment at undergraduate Dental Schools of Brazil were collected over a period of 8 months. Patient-related data included age, gender, first dental visit, tooth brushing frequency, number of remaining teeth, and previous endodontic treatment, and tooth-related information regarding number, type, and location in the mouth of teeth that need RCT, waiting time for the endodontic treatment, endodontic diagnosis, pain report, and dental crown condition was collected for each participant. Bivariate analysis (Chi-square test; p < 0.05) associated gender and tooth/patient-related conditions. Poisson regression analysis compared multiple endodontic need and exposure variables.

Results

Patients were mainly comprised of women (65.2%), aged 18-39 years (69.6%). Previous RCT was significantly more prevalent in women when compared to men (p=0.005). First dental visit at later moment (after 20 years of age) demonstrated 400% greater prevalence of multiple RCT demand when compared to patients that attended the dental office at age below seven years (p=0.032). Most of the patients presented only one tooth needing RCT (80.2%), mainly premolars (44.9%). Interestingly, women underwent more RCT in maxillary teeth (p=0.016) and significantly contributed with their report to the diagnosis process when compared to men (p=0.014). Regarding dental crown condition, 45.4% of all teeth registered unsatisfactory restorations, which were more pronounced in female patients (p=0.018). Unsatisfactory restorations or dental caries had 75% and 82%, respectively, less prevalence of multiple RCT indication when compared to sound dental crown (p=0.001).

Conclusions

RCT was undertaken more frequently in young female adults' premolars presenting unsatisfactory restorations. First dental visit, number of teeth with previous endodontic treatment, tooth group, and dental crown condition were significantly associated with the necessity of multiple endodontic treatments.

An Update on Nickel-Titanium Rotary Instruments in Endodontics: Mechanical Characteristics, Testing and Future Perspective-An Overview

Since the introduction of Nickel-Titanium alloy as the material of choice for the manufacturing of endodontic rotary instruments, the success rate of the root canal therapies has been significantly increased. This success mainly arises from the properties of the Nickel-Titanium alloy: the biocompatibility, the superelasticity and the shape memory effect. Those characteristics have led to a reduction in time of endodontic treatments, a simplification of instrumentation procedures and an increase of predictability and effectiveness of endodontic treatments. Nevertheless, the intracanal separation of Nickel-Titanium rotary instruments is still a major concern of endodontists, with a consequent possible reduction in the outcome rate. As thoroughly demonstrated, the two main causes of intracanal separation of endodontic instruments are the cyclic fatigue and the torsional loads. As results, in order to reduce the percentage of intracanal separation research and manufacturers have been focused on the parameters that directly or indirectly influence mechanical properties of endodontic rotary instruments. This review describes the current state of the art regarding the Nickel-Titanium alloy in endodontics, the mechanical behavior of endodontic rotary instruments and the relative stresses acting on them during intracanal instrumentation, highlighting the limitation of the current literature.

Trends of endodontic and periapical status in adult Danish populations from 1997 to 2009: A repeated cross-sectional study

AIM

To compare the endodontic and periapical status of two similar adult Danish populations examined in 1997-1998 and 2007-2009, respectively.

METHODOLOGY

Two populations from Aarhus County, Denmark (age range: 20-64 years) were randomly selected using the Danish Civil Registration System. Full-mouth intraoral radiographs (14 periapical, 2 bitewing) of 616 individuals in 1997-1998 (C1: 16 018 teeth) and 398 individuals in 2007-2009 (C2: 10 668 teeth) were taken to ascertain the number of teeth, presence of root fillings (RFs) and apical periodontitis (AP) using the periapical index (PAI). T-tests with unequal variances were used to assess differences between C1 and C2 with respect to age and the number of teeth. Multivariable and multinomial logistic regression analyses were used to assess the effect of cohort, age and tooth type on the prevalence and relative frequency of RFs and AP.

RESULTS

Mean age and mean number of teeth were higher in C2 than C1 (age; C1: 42.3 years, C2: 44.6 years; p = .003), (teeth; C1: 26.0, C2: 26.8; p < .001). The prevalence of root filled teeth was lower in C2 than C1 (C1: 51.8%, C2: 45.0%; p = .03); however, the prevalence of AP was similar (C1: 42.0%, C2: 45.0%). The relative frequency of root filled teeth was lower in C2 than C1 (C1: 4.8%, C2: 3.6%; p = .004), although the individuals were older in C2. The relative frequency of AP was similar in the two cohorts (C1: 3.3%, C2: 3.6%; p = .42). The relative frequency of AP in non-root filled teeth doubled from 0.9% in C1 to 1.8% in C2. C2 had higher PAI scores than C1 for root filled and non-root filled teeth, despite age correction (p ≤ .0007).

CONCLUSIONS

Two similar general Danish populations examined, respectively, in 1997-1998 and 2007-2009, were associated with a decreasing trend in the prevalence and relative frequency of RFs over the decade. There was no difference in relative frequency of AP in root filled teeth, but an increase in relative frequency of AP in non-root filled teeth. Further population-based studies including analysis of non-root filled teeth using the full-scale PAI and quality assessment of restorations are recommended.

Effect of prosthetic restorations and root canal fillings on periapical health in a selected patient group

Aims To examine the effect of the quality of root canal fillings and prosthetic restorations on the frequency of apical periodontitis (AP).Methodology A total of 200 radiographs of 1,098 teeth with indirect restorations were selected. Each case was documented by age, sex, tooth location, tooth type, restoration type and presence of root canal treatment (RCT). Teeth were categorised as healthy or diseased considering periapical health. The quality of RCT and prosthetic restorations was categorised by radiographic and clinical examinations. Data were analysed using chi-squared test and logistic regression.Results Inadequate prosthetic restorations were found to be less healthy than the adequate ones. Statistical significance was found in teeth with RCT, which had a higher rate of AP (15.8%). Root-filled teeth categorised as inadequately treated (24.1%) were significantly unhealthier than the adequately root-filled teeth. Teeth with inadequate prosthetic restorations and RCT had an increase in AP risk of 6.41 and 20.74 times, respectively (p <0.05).Conclusions Results showed that AP risk was increased by both inadequate RCT and prosthetic restorations. Quality of RCT significantly affected periapical health more than the quality of prosthetic restorations. Not only radiographic but also clinical examination of restorations is required for successful evaluation.

Influence of post type on periapical status: a prospective study in a Brazilian population

OBJECTIVES

This prospective study assessed the effect of post type used to restore endodontically treated teeth in the onset, progression, and remission of periapical lesions.

MATERIALS AND METHODS

One hundred and forty teeth (92 patients) were endodontically treated and received a glass fiber post or a cast metal post and a final restoration at a University Clinic by undergraduate students. All patients were followed up for a mean period of 5.1 ± 2.2 years. Periapical Index (PAI) was used for endodontic assessment. Two calibrated and blind examiners assessed the radiographs. The longevity of the endodontic treatment was analyzed using Kaplan-Meier statistics.

RESULTS

Of the included teeth, 67.1% received glass fiber posts while 32.9% received cast metal posts. There were 4 endodontic failures, two glass fiber posts with a PAI = 3 in the baseline and PAI = 4 in the last follow-up, and one PAI = 4 in baseline and last follow-up. One cast metal post-failure was PAI = 4 in the baseline and the last follow-up. After 9.4 years, the overall success rate of the endodontic treatment was 97.1% (p = 0.7).

CONCLUSIONS

The tested posts presented similar endodontic healing. Precautions taken during endodontic therapy, post cementation, and final restoration are more likely to be responsible for the success of endodontic treatment rather than a specific type of post. Clinical relevance The type of post is not related to the success of the endodontic treatment.

Prevalence of Lateral Radiolucency, Apical Root Resorption and Periapical Lesions in Portuguese Patients: A CBCT Cross-Sectional Study with a Worldwide Overview

Objective:

Apical periodontitis develops when bacteria, or their by products, migrate from the infected root canal system space to the surrounding apical tissues. The objective of the present multi-center cross-sectional study was to analyze the prevalence of lateral radiolucency, apical root resorption and periapical lesions in 7 districts of Portugal using cone-beam computed tomographic (CBCT) assessment.

Methods:

A total of 1,249 CBCT scans, from 11 dental clinics, were screened. Data regarding 22,899 teeth was included. For each tooth the recorded data was the presence of lateral radiolucency, apical root resorption, periapical lesions, previous root canal treatment, missed root canals, length of root canal filling (short, good or overfilling) and type of coronal restoration (intact tooth, non-restored, filling or crown). Differences between districts were tested using chi-squared. A P<0.05 was considered significant.

Results:

The proportion of lateral radiolucency ranged between 0.0% (Aveiro, Braga and Coimbra) and 0.9% (Lisbon), while the prevalence of apical root resorption ranged from 0.0% (Braga and Coimbra) to 3.0% in Setubal. The nationwide proportion of lateral radiolucency was 0.4%, while for apical root resorption was 1.1%. The prevalence of periapical lesions varied from 4.1% (Braga) and 13.0% (Lisbon) with a nationwide proportion of 10.0%. Significant differences were noted between districts (P<0.05).

Conclusion:

The prevalence of lateral radiolucency and apical root resorption were low in all districts. Root canal filled teeth were associated with higher periapical lesions proportions than non-treated teeth. Independently of the assessed district, the periapical status may be influenced by both quality of the endodontic treatment and coronal restoration.

Outcome of Root Canal Treatments Provided by Endodontic Postgraduate Students. A Retrospective Study

The aim of this study was to assess the preoperative, intraoperative, and postoperative factors that influenced complete periapical healing in teeth that underwent primary root canal treatment (RCT), in patients treated by postgraduate students in endodontics. Factors were retrieved and compared with the periapical status during the follow-up visit. Healing was considered as the absence of clinical and radiological symptoms. Variables significantly associated by the chi-squared test were included in a logistic regression model (LRM). Preoperative factors associated with healing were: American Society of Anesthesiology (ASA) status (p = 0.01); the absence of preoperative pain (p = 0.04); positive response to pulp tests; when the RCT cause was caries, pain, abscess, or sinus tract; probing depth <4 mm; the absence of mobility; absence or <4 mm periapical lesion (p < 0.01). In the LRM, the factors included were: absence or <4 mm periapical lesion; probing depths <4 mm; RCT caused by caries, pain, abscess, or sinus tract; the tooth was not a bridge abutment. Postoperative factors were: teeth with direct restoration; teeth that did not act as a support for a fixed prosthetic restoration; the favorable condition of the coronal restoration (p < 0.01). In the LRM, only the status of the coronal restoration was included. Preoperative conditions and the adequate fit of the coronal restoration influenced the outcome of RCT.

Assessment of the quality of endodontic re-treatment and changes in periapical status on a postgraduate endodontic clinic

OBJECTIVE

The aim of this study was to assess endodontic retreatment outcomes based on quality of obturation and healing.

MATERIALS AND METHODS

A total number of 223 radiographs of patients who had received endodontic retreatment during the period (2008-2015) at a postgraduate teaching clinic were selected. Unreadable radiographs were all excluded. From the original sample of 223 in total 24 radiographs were discarded. The final sample thus consisted of 199 root canal fillings. All radiographs were individually evaluated for the density of the root filling as well as the distance between the end of the root canal filling and radiographic apex based on a six-point scoring system. Subsequently, patients were reviewed and follow up periapical radiographs were exposed. The outcome of healing was assessed using the Periapical Index (PAI) scoring system. The data were analysed using Chi Square test (p < 0.05).

RESULTS

The study revealed that 78.9 % of the endodontic retreatments were both homogeneity and length acceptable. The corresponding figure was only 13.1 % before endodontic retreatment. Conversely, homogeneity and length unacceptable before endodontic retreatment was 47.2 % reducing to a mere 2.5 % after retreatment. The results were statistically significant (P < 0.001). There was over 80 % improvement in periapical healing following endodontic retreatment and this was also statistically significant (P < 0.001).

CONCLUSION

There was a significant improvement in outcome after endodontic retreatment on the postgraduate endodontic clinic. The success rate of endodontic retreatment was over 70 % which is in line with the endodontic literature. Radiographic follow up confirmed some 81 % improvement in healing rate following endodontic retreatment.

CLINICAL SIGNIFICANCE

Endodontic re-treatment cases are normally categorised as high complexity and as such referral to specialist settings should be considered to help improve treatment outcomes.

Effectiveness of a reciprocating single file, single cone endodontic treatment approach: a randomized controlled pragmatic clinical trial

OBJECTIVES

To compare the root filling quality, the sealer extrusion, and the healing rates of apical lesions addressed via two endodontic treatment approaches. The hypothesis tested was that both techniques present similar apical periodontitis healing results.

MATERIALS AND METHODS

This study was a parallel-design, pragmatic, and randomized clinical trial. One hundred twenty anterior teeth with necrotic pulps and apical periodontitis were randomly allocated to be either instrumented with hand files and obturated with the lateral compaction technique or instrumented with a single file in a reciprocating movement and obturated with a single-cone technique. The root canal filling quality, the occurrence of sealer extrusion, and apical periodontitis healing were the outcomes of interest. Data were analyzed through chi-square analysis, and the odds ratio for healing was adjusted using a logistic regression model (α = 0.05).

RESULTS

No significant differences were observed between the endodontic techniques regarding the root filling quality or sealer extrusion. Six months after treatment, both endodontic techniques presented equivalent results regarding apical periodontitis healing. The healing rate was affected only by the periapical status at baseline.

CONCLUSIONS

The obturation of the root canal of the anterior teeth using reciprocating file-matched single cones presented a similar quality to that obtained with manual instrumentation followed by the lateral condensation technique. Similar healing rates of apical lesions were also observed.

CLINICAL RELEVANCE

For treating anterior teeth with apical periodontitis, a reciprocating single-file, single-treatment protocol was as effective as a traditional protocol combining hand instrumentation and the lateral compaction obturation technique.

Deep Learning for the Radiographic Detection of Apical Lesions

INTRODUCTION

We applied deep convolutional neural networks (CNNs) to detect apical lesions (ALs) on panoramic dental radiographs.

METHODS

Based on a synthesized data set of 2001 tooth segments from panoramic radiographs, a custom-made 7-layer deep neural network, parameterized by a total number of 4,299,651 weights, was trained and validated via 10 times repeated group shuffling. Hyperparameters were tuned using a grid search. Our reference test was the majority vote of 6 independent examiners who detected ALs on an ordinal scale (0, no AL; 1, widened periodontal ligament, uncertain AL; 2, clearly detectable lesion, certain AL). Metrics were the area under the receiver operating characteristic curve (AUC), sensitivity, specificity, and positive/negative predictive values. Subgroup analysis for tooth types was performed, and different margins of agreement of the reference test were applied (base case: 2; sensitivity analysis: 6).

RESULTS

The mean (standard deviation) tooth level prevalence of both uncertain and certain ALs was 0.16 (0.03) in the base case. The AUC of the CNN was 0.85 (0.04). Sensitivity and specificity were 0.65 (0.12) and 0.87 (0.04,) respectively. The resulting positive predictive value was 0.49 (0.10), and the negative predictive value was 0.93 (0.03). In molars, sensitivity was significantly higher than in other tooth types, whereas specificity was lower. When only certain ALs were assessed, the AUC was 0.89 (0.04). Increasing the margin of agreement to 6 significantly increased the AUC to 0.95 (0.02), mainly because the sensitivity increased to 0.74 (0.19).

CONCLUSIONS

A moderately deep CNN trained on a limited amount of image data showed satisfying discriminatory ability to detect ALs on panoramic radiographs.

Modalities of using endodontic nickel-titanium rotary instruments and factors influencing their implementation in dental practice

BACKGROUND

To establish the extent of using nickel titanium rotary instruments (NiTi-RIs), to identify reasons for using / not using NiTi-RIs, to explore usage modalities and to identify factors and measures that can increase implementation of NiTi-RIs in general dental practice.

METHODS

Two pilot questionnaires were conducted on academic staff members at College of Dentistry, Taibah University, general dentists (GDs) and endodontists to finalise the questionnaire. A sample size was calculated considering the expected and minimum accepted response rates (60 and 48%, respectively) and a 99.9% Confidence Level. The online-questionnaire was sent to 600 GDs and all endodontists (175) working in Saudi Arabia. A reminder was emailed after 10 weeks to encourage non-respondents to complete the questionnaire. Responses, were collected and converted into numerical data which were analysed using the Chi-square test (p = 0.05).

RESULTS

Significantly most respondents (71.9%) used NiTi-RIs (p < 0.001); with more endodontists (96.9%) than GDs (60%). Most users (62.5%) had been using NiTi-RIs for More than 3 years (p < 0001). The trend of using NiTi-RIs increased as participants' experience and the number of root-canal treatments performed per week increased (p = 0.021). While most respondents (45.3%) used NiTi-RIs because of faster root-canal preparation, the majority of non-users (85.3%) didn't do so because of high cost. The highest proportion (43.3%) reported better undergraduate education as the most important factor that can significantly increase NiTi-RIs usage. The majority (91.8%) prepared glide-path before using NiTi-RIs; especially with stainless steel hand-files (63.3%).

CONCLUSIONS

NiTi-RIs are relatively well adopted in Saudi dental practice. However, better education, especially during undergraduate training and lower cost can increase their usage. Overall, clinicians showed good awareness of NiTi-RIs usage aspects which reflected on usage modalities.