Long-term evaluation of endodontic and periodontal treatment

The endodontic-periodontal juncture: Where two worlds meet. An overview of endo-perio lesions

Endodontic and periodontal infections can be difficult to differentiate from one another and often share common clinical features making diagnosis challenging. The aim of this review is to discuss endodontic and periodontal infections in situations where they occur concurrently, or where one influences the other. The available literature investigating endodontic and periodontal infections was examined for contemporary knowledge regarding endodontic-periodontal interactions. Strategies to facilitate diagnosis and treatment planning are discussed. When endodontic and periodontal infections occur together, or signs and symptoms are similar, diagnosis can be challenging. Determining the primary source of infection is imperative to ensure appropriate treatment planning. The pulp and periodontal tissues are intimately related, with many possible pathways for infection from one to the other. Diagnosis of the primary source of the infection can be difficult and sometimes an inter-disciplinary approach to treatment is required. © 2023 Australian Dental Association.

A retrospective assessment of different endodontic treatment protocols

Background

The aim of this study was to assess the clinical impact of non-surgical root canal treatments (NSRCT) performed with different treatment protocols on the probability of tooth survival without untoward events and to identify predictors influencing the outcome.

Methods

During the period from July 1999 to October 2016, 5,858 patients were identified in which 9,967 NSRCTs were performed. The treatments were followed up and divided into three groups. In Group 1 root canal treatment was performed with hand instruments, in Group 2 with multiple file rotary instruments and passive ultrasonic irrigation (PUI), and Group 3 was treated with Reciproc instruments and PUI. Untoward events were defined as orthograde retreatment, apicoectomy or extraction of the tooth after initial treatment. Weibull regression was used to analyse the data.

Results

A total of 9,938 cases could be included into the analyses. The results showed 5-years predicted survival rates without untoward events of 73.9% (95% CI [71.7%–76.1%]), 75.1% (95% CI [71.7%–78.0%]) and 78.4% (95% CI [75.1%–81.4%]) for study group 1 (N = 5,580), 2 (N = 1,700) and 3 (N = 2,658), respectively. The differences between Group 1 and 3 were statistically significant (p < 0.006). Higher age of the patient (per year increase) and number of earlier NSRCTs (per unit increase) reduce the survival without untoward events statistically significant (both p < 0.02), while treatment of premolars had a statistically significant lower hazard ratio [0.89 (95% CI [0.79–0.99]; p = 0.030)] compared to treatment of molars and anterior teeth. A higher number of supportive periodontal treatments (per unit increase) improved tooth survival without untoward events highly significant (p < 0.0001).

Discussion

More recent endodontic treatment protocols involving reciprocating instruments and PUI appear to be associated with higher tooth survival rates without untoward events compared to hand instruments.

Histological changes within dental pulps in teeth with moderate-to-severe chronic periodontitis

AIM

To investigate the effect of chronic periodontitis on dental pulps by assessing histological changes in the pulps of teeth with moderate-to-severe periodontitis.

METHODOLOGY

A total of 242 teeth from 162 patients with moderate-to-severe periodontitis were collected, and histological changes in pulps were investigated by staining with haematoxylin and eosin. Baseline data were taken from the patients' records before extraction. The morphologic changes observed in the pulp were classified as degree I, degree II, degree III and degree IV. Statistical analysis of the severity of periodontitis and histological changes with the pulps was applied using the Mann-Whitney U rank sum test, whilst the contingency coefficient was used to analyse the inter-relationship between the severity of periodontitis and histological changes in the pulps.

RESULTS

The inter-relationship between the severity of periodontitis and histological changes in the pulps was 0.274 (P < 0.001), and significant differences existed between teeth with moderate periodontitis and severe periodontitis group (Z = 4.145, P < 0.001). The inter-relationship between attachment loss and histological changes in the pulps was 0.397 (P < 0.001). There were significant differences in the histological changes amongst teeth with various degrees of attachment loss (χ(2) = 33.023, P < 0.001) and amongst teeth in different locations (χ(2) = 23.163, P < 0.001).

CONCLUSIONS

There was a positive association between the severity of periodontitis and histological changes within the pulp. More attachment loss was correlated with pathological changes within the dental pulp.

Examination of the prevalence of periapical lesions and technical quality of endodontic treatment in a Turkish subpopulation

OBJECTIVE

The objective of this study was to investigate the prevalence of periapical lesions by evaluating the periapical status and to evaluate the relationship between the technical quality of endodontic treatments and presence of periapical lesions in a Turkish subpopulation.

STUDY DESIGN

A total of 11,542 teeth of 438 patients were radiographically evaluated. Presence of endodontic treatment and obturation levels, coronal restorations, and degree of root canal curvature angles were noted. Apical status was assessed by the Periapical Index Scores (PAI). The χ(2) test was used for statistical analysis.

RESULTS

Among all teeth, 179 (1.55%) had endodontic treatment and 189 (1.63%) had periapical lesions. Of 179 endodontically treated teeth, 68 (37.99%) had periapical lesions. The prevalence of periapical lesions was found to be significantly high among underfilled teeth (P < .001). In most underfilled teeth, the presence of severe curvatures was particularly of interest. Prevalence of inadequate coronal restorations was significantly high among the teeth with periapical lesions, whether endodontically treated or not (P < .001).

CONCLUSIONS

The findings of the present study indicate that considerable effort should be spent by dental practitioners to improve the technical quality of root canal fillings.

Association of endodontic involvement with tooth loss in the Veterans Affairs Dental Longitudinal Study

INTRODUCTION

The effect of endodontic involvement on tooth loss has not been quantified, so the present study aimed to assess this relationship after controlling for other relevant risk factors for tooth loss.

METHODS

We analyzed data from 791 participants (18,798 teeth) in the Veterans Affairs Dental Longitudinal Study. Potential tooth-level and person-level covariates were fitted into marginal proportional hazards models, including both apical radiolucencies (AR) and root canal therapy (RCT) status as time-dependent variables. Survival curves were plotted for teeth according to their AR and RCT status.

RESULTS

Both current AR and RCT status were associated with increased risk of tooth loss (P < .01), after controlling for baseline levels of periodontal disease, caries, tooth type, number of proximal contacts, number of teeth, age, education, and smoking history. Root canal filled (RCF) teeth seemed to have better survival than non-RCF teeth among teeth with AR but worse survival than non-RCF teeth among teeth without AR.

CONCLUSIONS

Endodontic involvement was associated with tooth loss, controlling for other potential risk factors. Additional prospective studies are needed to provide better evidence as to the impact of endodontic involvement on tooth loss.

Strategies for the endodontic management of concurrent endodontic and periodontal diseases

Endodontic and periodontal diseases can provide many diagnostic and management challenges to clinicians, particularly when they occur concurrently. As with all diseases, a thorough history combined with comprehensive clinical and radiographic examinations are all required so an accurate diagnosis can be made. This is essential since the diagnosis will determine the type and sequence of treatment required. This paper reviews the relevant literature and proposes a new classification for concurrent endodontic and periodontal diseases. This classification is a simple one that will help clinicians to formulate management plans for when these diseases occur concurrently. The key aspects are to determine whether both types of diseases are present, rather than just having manifestations of one disease in the alternate tissue. Once it is established that both diseases are present and that they are as a result of infections of each tissue, then the clinician must determine whether the two diseases communicate via the periodontal pocket so that appropriate management can be provided using the guidelines outlined. In general, if the root canal system is infected, endodontic treatment should be commenced prior to any periodontal therapy in order to remove the intracanal infection before any cementum is removed. This avoids several complications and provides a more favourable environment for periodontal repair. The endodontic treatment can be completed before periodontal treatment is provided when there is no communication between the disease processes. However, when there is communication between the two disease processes, then the root canals should be medicated until the periodontal treatment has been completed and the overall prognosis of the tooth has been reassessed as being favourable. The use of non-toxic intracanal therapeutic medicaments is essential to destroy bacteria and to help encourage tissue repair.

Restoration of the root-filled tooth: pre-operative assessment

This is the first in a series of four papers related to the management of root canal treated teeth. When teeth compromised by extensive restorations become non-vital, suggestions have been given as to how root canal treatment can be carried out with the greatest chance of success. Once root canal treated, either by a previous dentist or by the current dentist, a review of the assessment process that should be carried out prior to placing costly indirect definitive restorations is given. It will be clear that post-retained restorations are mainly reserved for anterior or single-rooted teeth, posterior teeth rarely requiring a post for core retention. The second paper in this series describes the basic tooth preparation that should be carried out prior to placing a post. Depending on the type of post system used, further modifications to tooth preparation may be required and the cementation techniques may also have to be modified. The third paper therefore discusses the various post types, when and how they should be used for optimum results. The final paper addresses reinforcement and restoration of compromised root canals, such as those with immature, open apices, or those that have been over-prepared for previous post-retained restorations.

Levels of Evidence for the Outcome of Nonsurgical Endodontic Treatment

The purpose of this systematic review was (a) to search for clinical articles pertaining to success and failure of nonsurgical root canal therapy, and (b) to assign levels of evidence to these studies. Electronic and manual searches were conducted to identify studies published between January 1966 and September 2004 with information on the success and failure of nonsurgical root canal therapy. Articles were reviewed and graded for strength of level of evidence (LOE) from one (highest level) to five (lowest level). This review resulted in the identification of 306 clinical studies related to this topic area. Six articles were randomized controlled trials (RCTs, LOE 1). This search also identified 12 low-quality RCTs (LOE 2), 14 cohort studies (LOE 2), five case-control and eight cross sectional studies (LOE 3), four low-quality cohort studies (LOE 4), and five low-quality case-control studies (LOE 4). The majority (73) of the often-quoted "success and failure" studies were case series (LOE 4). The rest of the articles were descriptive epidemiological studies (42), case reports (114), expert opinions (18), literature reviews (4), and one meta-analysis. Based on these findings, it appears that a few high-level studies have been published in the past four decades related to the success and failure of nonsurgical root canal therapy. The data generated by this search can be used in future studies to specifically answer questions and test hypotheses relevant to the outcome of nonsurgical root canal treatment.

Radiographic features and outcome of root canal treatment carried out in the Łódź region of Poland

AIM

The aim of this study was to assess the radiographic features and factors affecting the long-term results of root canal treatment in the Lódź region of Poland.

METHODOLOGY

Three hundred and fifty-five periapical radiographs of previously endodontically treated teeth (282 root-filled teeth and 73 teeth with pulpotomy) from 236 patients were evaluated in the study. The patients were aged from 15 to 76 years and randomly selected amongst subjects referred to the Institute of Dentistry. Medical University of Lódź and two private dental practices. The radiographs were examined by the authors according to criteria proposed by De Cleen et al. (1993) using an illuminated viewbox in a dark room. The Fisher's exact test was used to compare the frequencies in teeth groups.

RESULTS

Amongst root-filled teeth, 49% were adequately filled within 0-2 mm of the radiographic apex. Periapical radiolucencies were observed in 25% of root-filled teeth. Teeth without periapical pathosis were more often filled within 0-2 mm of the apex (59%) than teeth with pathosis (17%). Teeth were most often adequately filled (64%) in patients attending the Institute of Dentistry. In patients attending the dental outpatients' departments, 71% of teeth were inadequately filled. Amongst the teeth treated with pulpotomy, 67% had a periapical radiolucency.

CONCLUSION

The radiographic technical quality of the root canal treatment was associated with the outcome that root fillings of adequate standard were associated with health more often than inadequate root fillings. Pulpotomy was associated with periapical disease in the majority of cases.

Factors influencing the long-term results of endodontic treatment: a review of the literature

The purpose of this review of the literature is to examine the factors and their influence on the outcome of endodontic treatments, and also to attempt to have an authors' consensus concerning the impact of these factors on long-term results. The documentary research was conducted using the meta-analysis principles of critical reading of the literature. Two groups of factors can be identified regarding the outcome of endodontic treatments: those which influence the success of the procedure and those which do not significantly affect the success rate. Agreement is obtained in all studies on two major factors, the preoperative periapical status and the apical limit of the obturation, which appear to strongly influence the success of endodontic therapy. This review highlights the methodological problems of retrospective studies and points out the need for consensus regarding the evaluation criteria of root canal therapy.

Relationship between number of proximal contacts and survival of root canal treated teeth

AIM

The present study tested the hypothesis that having two proximal contacts (PCs) at access is associated with improved survival of root canal treated (RCT) teeth, controlling for important presenting conditions, endodontic variables and restorative factors.

METHODOLOGY

A treatment database at the University of Iowa College of Dentistry was used to identify permanent teeth undergoing obturation between 1 July 1985 and 31 December 1987. The list was restricted to teeth of patients with at least one dental visit in each two-year interval from 1985 to 1996, and a simple random sample of 280 patients (n = 400 teeth) was selected. Dental charts, radiographs, and computerized databases were examined to ascertain variables of interest and to verify study inclusion criteria. Kaplan-Meier survival estimates were generated for the 221 teeth satisfying study inclusion criteria. Multivariate Cox models were developed, with standard errors adjusted to account for clustering of teeth within patients.

RESULTS

The final Cox model showed that teeth with < or =1 PC at access were lost at a rate three times that of teeth with 2 PCs (hazard ratio = 3.1; 95% confidence interval = 1.9-5.1), controlling for tooth type, presence of radiographic caries at access, and presence of a crown before or after obturation.

CONCLUSIONS

Because RCT teeth with two PCs at access experienced substantially better survival than teeth with fewer than two PCs, the influence of PCs on prognosis should be recognized during treatment planning. Future research should employ prospective study designs, capture additional variables, and provide data to support endodontic treatment decisions.