The latest in endodontic research

Dr. Kishor Gulabivala presents the latest literature, keeping you up-to-date with the most relevant research

Pulp treatment for extensive decay in primary teeth
Smail-Faugeron V, Courson F, Durieux P, Muller-Bolla M, Glenny AM, Fron Chabouis H. Cochrane Database of Systematic Reviews. [Update of Cochrane Database Syst Rev, 2003] (2014) 8:CD003220

Abstract

Aim: In children, dental caries is among the most prevalent chronic diseases worldwide. Pulp interventions are indicated for extensive tooth decay. Depending on the severity of the disease, three pulp treatment techniques are available: direct pulp capping, pulpotomy, and pulpectomy. After treatment, the cavity is filled with a medicament. This was an update of a Cochrane review first published in 2003. The previous review found insufficient evidence regarding the relative efficacy of these interventions, combining one pulp treatment technique and one medicament. The aim was to assess the effects of different pulp treatment techniques and associated medicaments for the treatment of extensive decay in primary teeth.

Methodology: The Cochrane Oral Health Group’s Trials Register (to 25 October 2013) was searched, the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2013, Issue 9), MEDLINE via OVID (1946 to 25 October 2013), EMBASE via OVID (1980 to 25 October 2013), and the Web of Science (1945 to 25 October 2013). The OpenGrey for Grey Literature and the U.S. National Institutes of Health Trials Register, and the World Health Organization (WHO) Clinical Trials Registry Platform for ongoing trials were searched. There were no restrictions placed on the language or date of publication when searching the electronic databases. Eligible studies were randomized controlled trials comparing different pulp interventions combining a pulp treatment technique and a medicament in children with extensive decay involving dental pulp in primary teeth. Two review authors independently carried out data extraction and risk of bias assessment in duplicate. The authors of randomized controlled trials were contacted for additional information, if necessary. The primary outcomes were clinical failure and radiological failure, as defined in trials, at 6, 12, and 24 months. Data synthesis was performed with pairwise meta-analyses using fixed-effect models. Statistical heterogeneity was assessed using by I(2) coefficients.

Results: 47 trials (3,910 randomized teeth) were included compared to three trials in the previous version of the review published in 2003. All trials were single center and small sized (median number of randomized teeth: 68). Overall, the risk of bias was low in only one trial with all other trials being at unclear or high risk of bias. The overall quality of the evidence was low. The 47 trials examined 53 different comparisons: 25 comparisons between different medicaments/techniques for pulpotomy, 13 comparisons between different medicaments for pulpectomy, 13 comparisons between different medicaments for direct pulp capping, and two comparisons between pulpotomy and pulpectomy. Regarding pulpotomy, 14 trials compared mineral trioxide aggregate (MTA) with formocresol (FC). MTA reduced both clinical and radiological failures at 6, 12, and 24 months, although the difference was not statistically significant. MTA also showed favorable results for all secondary outcomes measured; although again, differences between MTA and FC were not statistically significant (with the exception of pathological root resorption at 24 months and dentin bridge formation at 6 months). MTA showed favorable results compared with calcium hydroxide (CH) (two trials) for all outcomes measured, but the differences were not statistically significant (with the exception of radiological failure at 12 months). When comparing MTA with ferric sulfate (FS) (three trials), MTA had statistically significantly fewer clinical, radiological, and overall failures at 24 months. This difference was not shown at 6 or 12 months. FC was compared with CH in seven trials and with FS in seven trials. There was a statistically significant difference in favor of FC for clinical failure at 6 and 12 months, and radiological failure at 6, 12, and 24 months. FC also showed favorable results for all secondary outcomes measured, although differences between FC and CH were not consistently statistically significant across time points. The comparisons between FC and FS showed no statistically significantly difference between the two medicaments for any outcome at any time point. For all other comparisons of medicaments used during pulpotomies, pulpectomies, or direct pulp capping, the small numbers of studies and the inconsistency in results limit any interpretation.

Conclusions: There was no evidence to identify one superior pulpotomy medicament and technique clearly. Two medicaments may be preferable: MTA or FS. The cost of MTA may preclude its clinical use, and therefore, FS could be used in such situations. Regarding other comparisons for pulpectomies or direct pulp capping, the small numbers of studies undertaking the same comparison limits any interpretation.

Correlation between clinical and histologic pulp diagnoses
Ricucci D, Loghin S, Siqueira JF Jr. Journal of Endodontics. (2014) 40(12):1932-9

Abstract

Aim: Clinicians routinely face conditions in which they have to decide whether the dental pulp can be saved or not. This study evaluated how reliable the clinical diagnosis of normal pulp/reversible pulpitis (savable pulp) or irreversible pulpitis (nonsavable pulp) is when compared with the histologic diagnosis.

Methodology: The study material consisted of 95 teeth collected consecutively in a general practice over a 5-year period and extracted for reasons not related to this study. Based on clinical criteria, teeth were categorized as having normal pulps, reversible pulpitis, or irreversible pulpitis. The former two were grouped together because they represent similar conditions in terms of prognosis. Teeth were processed for histologic and histobacteriologic analyses, and pulps were categorized as healthy, reversibly inflamed, or irreversibly inflamed according to defined criteria. The number of matching clinical/histologic diagnosis was recorded.

Results: The clinical diagnosis of normal pulp/reversible pulpitis matched the histologic diagnosis in 57 of 59 (96.6%) teeth. Correspondence of the clinical and histologic diagnosis of irreversible pulpitis occurred in 27 of 32 (84.4%) cases. Infection advancing to the pulp tissue was a common finding in teeth with irreversible pulpitis but was never observed in normal/reversibly inflamed pulps.

Conclusions: Findings using defined criteria for clinical and histologic classification of pulp conditions revealed a good agreement, especially for cases with no disease or reversible disease. This means that the classification of pulp conditions as normal pulps, reversible pulpitis, and irreversible pulpitis has high chances of guiding the correct therapy in the large majority of cases. However, there is still a need for refined and improved means for reliable pulp diagnosis.

Root canal therapy reduces multiple dimensions of pain: a national dental practice-based research network study
Law AS, Nixdorf DR, Rabinowitz I, Reams GJ, Smith JA Jr, Torres AV, Harris DR, National Dental PBRN Collaborative Group. Journal of Endodontics. (2014) 40(11):1738-45

Abstract

Aim: Initial orthograde root canal therapy (RCT) is used to treat dentoalveolar pathosis. The effect RCT has on pain intensity has been frequently reported, but the effect on other dimensions of pain has not. Also, the lack of large prospective studies involving diverse groups of patients and practitioners who are not involved in data collection suggest that there are multiple opportunities for bias to be introduced when these data are systematically aggregated.

Methodology: This prospective observational study assessed pain intensity, duration, and its interference with daily activities among RCT patients. Sixty-two practitioners (46 general dentists and 16 endodontists) in the National Dental Practice-Based Research Network enrolled patients requiring RCT. Patient-reported data were collected before, immediately after, and 1 week after treatment using the Graded Chronic Pain Scale.

Results: The enrollment of 708 patients was completed over 6 months with 655 patients (93%) providing 1-week follow-up data. Before treatment, patients reported a mean (+standard deviation) worst pain intensity of 5.3 + 3.8 (0-10 scale), 50% had “severe” pain (>7), and mean days in pain and days pain interfered with activities were 3.6 + 2.7 and 0.5 + 1.2, respectively. After treatment, patients reported a mean worst pain intensity of 3.0 + 3.2, 19% had “severe” pain, and mean days in pain and days with pain interference were 2.1 + 2.4 and 0.4 + 1.1, respectively. All changes were statistically significant (P < .0001).

Conclusions: RCT is an effective treatment for patients experiencing pain, significantly reducing pain intensity, duration, and related interference. Further research is needed to reduce the proportion of patients experiencing “severe” postoperative pain.

Prevalence of persistent pain 3 to 5 years post primary root canal therapy and its impact on oral health-related quality of life: PEARL Network findings
Vena DA, Collie D, Wu H, Gibbs JL, Broder HL, Curro FA, Thompson VP, Craig RG, PEARL Network Group. Journal of Endodontics. (2014) 40(12):1917-21

Abstract

Aim: The frequency of persistent pain 3 to 5 years after primary root canal therapy and its impact on the patient’s perceived oral health-related quality of life was determined in a practice-based research network.

Methodology: All patients presenting to participating network practices who received primary root canal therapy and restoration for a permanent tooth 3 to 5 years previously were invited to enroll. Persistent pain was defined as pain occurring spontaneously or elicited by percussion, palpation, or biting. The patient also completed an oral health-related quality of life questionnaire (Oral Health Impact Profile-14).

Results: Sixty-four network practices enrolled 1,323 patients; 13 were ineligible; 12 did not receive a final restoration; and 41 were extracted, leaving 1,257 for analysis. The average time to follow-up was 3.9 + 0.6 years; 5% (63/1257) of the patients reported persistent pain, whereas 24 of 63 (38%) exhibited periapical pathosis and/or root fracture (odontogenic pain). No obvious odontogenic cause for persistent pain was found for 39 of 63 (62%). Teeth treated by specialists had a greater frequency of persistent pain than teeth treated by generalists (9.3% versus 3.0%, respectively; P < .0001). Sex, age, tooth type, type of dentist, and arch were not found to be associated with nonodontogenic persistent pain; however, ethnicity and a preoperative diagnosis of pulpitis without periapical pathosis were. Patients reporting pain with percussion tended to experience pain with other stimuli that negatively impacted quality of life including oral function and psychological discomfort and disability.

Conclusions: These results suggest that a small percentage (3.1%) of patients experience persistent pain not attributable to odontogenic causes 3 to 5 years after primary root canal therapy that may adversely impact their quality of life.
Treatment outcome of mineral trioxide aggregate or calcium hydroxide direct pulp capping: long-term results
Mente J, Hufnagel S, Leo M, Michel A, Gehrig H, Panagidis D, Saure D, Pfefferle T. Journal of Endodontics. (2014) 40(11):1746-51

Abstract Aim: This controlled, historic cohort study project continues a previously reported trial aiming to assess treatment outcome of direct pulp capping with mineral trioxide aggregate (MTA) versus calcium hydroxide (CH). Potential prognostic factors were re-evaluated on the basis of a larger sample size and longer follow-up periods. Methodology: Clinical and radiographic outcomes of 229 teeth treated with direct pulp capping between 2001 and 2011 were investigated 24 up to 123 months post-treatment (median = 42 months). Pre-, intra-, and postoperative information was evaluated and statistically analyzed using a logistic regression model as well as generalized estimating equation logit models.

Results: Two hundred and five patients (229 teeth) were available for follow-up (74% recall rate). The overall success rates were 80.5% (95% confidence interval [CI], 74.5-86.5) of teeth in the MTA group (137/170) and 59% (95% CI, 46.5-71.5) of teeth in the CH group (35/59). Multivariate analyses (generalized estimating equation logit model) indicated a significantly increased risk of failure for teeth that were directly pulp capped with CH compared with MTA (odds ratio = 2.67; 95% CI, 1.36-5.25; P = .001). Teeth that were permanently restored >2 days after direct pulp capping had a significantly worse prognosis irrespective of the pulp capping material chosen (odds ratio = 3.18; 95% CI, 1.61-6.3; P = .004).

Conclusions: The results of this study indicate that MTA provides better long-term results after direct pulp capping compared with CH. Placing a permanent restoration immediately after direct pulp capping is recommended.

Volumetric pulp changes after orthodontic treatment determined by cone-beam computed tomography
Venkatesh S, Ajmera S, Ganeshkar SV. Journal of Endodontics. (2014) 40(11):1758-63

Abstract

Aim: The purpose of this study was to observe and evaluate three-dimensional pulp cavity changes during orthodontic treatment.

Methodology: Eighty-seven patients formed the study sample and were divided into an experimental group (48 patients) and a control group (39 patients). Cone-beam computed tomographic (CBCT) records were obtained before the start of the treatment (T0) and after space closure for the experimental group, whereas for the control group CBCT images were obtained approximately 17-18 months (T1) after obtaining the first image (T0). CBCT data were reconstructed with surface and volume rendering software (Mimics; Materialise, Leuven, Belgium), and the volumetric images were modified to display the teeth from various orientations. Six anterior teeth were segmented and their pulps isolated. Paired t-test was used to check for statistical significance.

Results: The difference in the pulp volume was statistically significant at P < .05 for all the anterior teeth in the experimental group and at P < .05 for the right canine, P < .05 for the right and left lateral incisors, and P < .05 for the left central in the control group. Conclusions: Orthodontic treatment in the experimental group produced a significant decrease in the size of the pulp, which was statistically significant. Direct pulp capping after a carious exposure versus root canal treatment: a cost-effectiveness analysis Schwendicke F, Stolpe M. Journal of Endodontics. (2014) 40(11):1764-70

Abstract Aim: Excavation of deep caries often leads to pulpal exposure even in teeth with sensible, non-symptomatic pulps. Although direct pulp capping (DPC) aims to maintain pulpal health, it frequently requires follow-up treatments like root canal treatment (RCT), which could have been performed immediately after the exposure, with possibly improved outcomes. The long-term cost-effectiveness of both strategies was quantified and compared. Methodology: A Markov model was constructed following a molar with an occlusally located exposure of a sensible, non-symptomatic pulp in a 20-year-old male patient over his lifetime. Transition probabilities or hazard functions were estimated based on systematically and nonsystematically assessed literature. Costs were estimated based on German healthcare, and cost-effectiveness was analyzed using Monte Carlo microsimulations.

Results: Despite requiring follow-up treatments significantly earlier, teeth treated by DPC were retained for long periods of time (52 years) at significantly reduced lifetime costs (€545 versus €701) compared with teeth treated by RCT. For teeth with proximal instead of occlusal exposures or teeth in patients > 50 years of age, this cost-effectiveness ranking was reversed. Although sensitivity analyses found substantial uncertainty regarding the effectiveness of both strategies, DPC was usually found to be less costly than RCT.

Conclusions: Both DPC and RCT were suitable to treat exposed vital, nonsymptomatic pulps. DPC was more cost-effective in younger patients and for occlusal exposure sites, whereas RCT was more effective in older patients or teeth with proximal exposures. These findings might change depending on the healthcare system and underlying literature-based probabilities.

The effect of rubber dam usage on the survival rate of teeth receiving initial root canal treatment: a nationwide population-based study
Lin PY, Huang SH, Chang HJ, Chi LY. Journal of Endodontics. (2014) 40(11):1733-7

Abstract

Aim: The aim of the present study was to investigate whether rubber dam usage affects the survival rate of initial RCT using a nationwide population-based database.

Methodology: A total of 517,234 teeth that received initial RCT between 2005 and 2011 met the inclusion criteria and were followed until the end of 2011. Univariate and multivariate Cox proportional hazards models were used to estimate the effects of rubber dam usage on the risk of tooth extraction after initial RCT.

Results: Of the 517,234 teeth, 29,219 were extracted, yielding a survival rate of 94.4%. The survival probability of initial RCT using rubber dam after 3.43 years (the mean observed time) was 90.3%, which was significantly greater than the 88.8% observed without the use of rubber dams (P < .0001). After adjusting for age, sex, tooth type, hospital level, tooth scaling frequency per year after RCT, and systemic diseases, including diabetes and hypertension, the tooth extraction hazard ratio for the RCT with rubber dams was significantly lower than that observed for RCT without rubber dams (hazard ratio = 0.81; 95% confidence interval, 0.79-0.84).

Conclusions: The use of a rubber dam during RCT could provide a significantly higher survival rate after initial RCT. This result supports that rubber dam usage improves the outcomes of endodontic treatments.