Large-scale clinical endodontic research in the National Dental Practice-Based Research Network: study overview and methods

Fast self-curing α-tricalcium phosphate/β-dicalcium silicate composites beneficial for root canal sealing treatment

Objectives

α-tricalcium phosphate (α-TCP) and β-dicalcium silicate (β-C2S) have attracted much attention since these two types of self-curing Ca-phosphate and Ca-silicate are valuable biomaterials for bone defect or endodontic therapy. However, the injectable paste of their individual with high liquid/solid ratio is junior for root canal sealing due to very long self-setting time, low pH value and/or much volume shrinkage during paste-to-cement transformation.

Methods

Our studies evaluated the effect of biphasic ratio, liquid/solid ratio and pH condition of aqueous medium on setting time and mechanical strength of this biphasic composite cement, and also the hydroxyapatite re-mineralization potential and anti-microleakage level of the cements with different α-TCP/β-C2S ratio were explored in vitro. A control group free of paste filler was included in the extracted teeth model. Dentine re-mineralization and microleakage degree were observed by scanning electron microscopy and microCT reconstruction analysis.

Results

It indicated that the weak acidic solution with pH value of 6.0 may produce a significantly shorter initial setting time (from 90 min to less 20 min) and expected final setting time (<150 min) for the biphasic composite (2:1 or 1:2) in comparison with the pure β-C2S. Notably, the phasic composites exhibited limited microleakage and induced hydroxyapatite mineralization in the dentine tubules. These hydraulic pastes also produced strong alkaline feature and appreciable compressive resistance (12–18 MPa) after setting for a very short time stage. Moreover, a link between the addition of α-TCP leading to fast re-mineralization reaction was established.

Significance

Our findings suggest that the appreciable self-setting and physicochemical properties adaption to root canal sealability make α-TCP/β-C2S composites as preferential candidates for endodontic treatments.

Present status and future directions of intracanal medicaments

Two fundamental goals of endodontic treatment are to prevent or treat apical periodontitis. From a predictive perspective, several variables can affect the outcome of root canal treatment. Some of these variables depend on intraoperative factors, which include irrigation technique, size of the apical preparation, use of intracanal medicaments or the number of appointments necessary to complete the treatment. However, the outcome may also be affected by host and microbial factors. The intensity of periradicular bone loss or tissue damage, the presence of preoperative pain and associated conditions such as mechanical allodynia and central sensitization, the anatomical complexity of the apical portion of the canal, and the virulence and longevity of the bacterial infection can all have a profound influence on the outcome. Furthermore, numerous medical conditions have been reported to decrease the capability of the immune system to heal the periapical tissues. It is the clinician's responsibility to analyse these variables and incorporate them into the disinfection strategy to maximize the chances of healing. This narrative review will focus on the present status of intracanal medicaments, the clinical indications for their use and future directions for research.

Preoperative Factors Associated with Anesthesia Failure for Patients Undergoing Nonsurgical Root Canal Therapy: A National Dental Practice-Based Research Network Study

INTRODUCTION

The aim of this study was to identify preoperative factors associated with local anesthesia failure.

METHODS

The National Dental Practice-Based Research Network (www.NationalDentalPBRN.org) data from 534 patients who received a nonsurgical root canal treatment completed in a single appointment were included in this analysis. Three methods for defining anesthesia failure were used: definition 1, patient-reported level of numbness; definition 2, provider-reported quality of anesthesia; and definition 3, provider-reported use of supplemental anesthesia. Fifty-one preoperative factors were investigated and analyzed individually against the overall failure rate for each method, and multivariate generalized estimating equation logistic models were fit with predictors chosen using stepwise model selection to evaluate factors that may interact with each other.

RESULTS

The overall anesthesia failure rates were 5%, 15%, and 30% for definitions 1, 2, and 3, respectively. Provider experience, diabetes, absence of sharp or aching pain, absence of smoking, and a fair expected outcome were associated with anesthesia failure (definition 1). Provider level of training, absence of a sinus tract, bite sensitivity, and stress making the pain worse were associated with anesthesia failure (definition 2). Provider level of training, pain provoked by stimulus, mandibular teeth, teeth with vital pulps, and pain interfering with daily activities were associated with the use of supplemental anesthesia (definition 3).

CONCLUSIONS

With the range of 5%-30% of anesthesia failures, a few common factors across the models assessed were elucidated. Providers with higher levels of training had significantly fewer anesthesia failures. Patient self-reported history of diabetes and preoperative pain-related interference with daily activities were associated with more anesthesia failures. Greater severity of various tooth-related pain characteristics, as a group but not individually, accounted for more anesthesia failures.

Establishment of a Danish endodontic practice-based research network: baseline data

OBJECTIVE

Clinical studies in endodontics are primarily performed in highly controlled environments using strict treatment protocols, inclusion and exclusion criteria, and high success rates have been reported. Most endodontic treatments are, however, performed in private practice, where is has been difficult to obtain similar high success rates. The aim of this pilot project was to evaluate the feasibility of performing practice-based research and to describe baseline information on endodontic procedures used in general practice in Denmark.

MATERIALS AND METHODS

The baseline data included information from dental practitioners, collected during 2017-2018. The dentists used the procedures and materials they normally would use. Data were systematized and analysed at Aarhus University.

RESULTS

Seventeen dentists provided information on 581 endodontic treatments. Half of the teeth had initially a necrotic pulp, 20% had a vital pulp and 28% were previously root-filled. Adaptation of contemporary technology such as mechanized instrumentation, use of magnification, seems to be well integrated among the participating dentists.

CONCLUSIONS

Overall, the endodontic treatments performed by the participating dentists follow international guidelines for good quality endodontic treatments. It is anticipated, that among Danish dentist there is basis for further practice-based research, but logistic issues need to be addressed.

3-year Outcome of Patients with Persistent Pain after Root Canal Treatment: The National Dental Practice-Based Research Network

INTRODUCTION

We measured the long-term outcomes of patients reporting persistent pain 6 months after root canal treatment (RCT) and assessed the characteristics differing patients with pain chronification from those with pain resolution.

METHODS

Forty-five patients previously found to have persistent pain 6 months post-RCT from the National Dental Practice-Based Research Network were approached for a 3-year follow-up, and 27 participated in the survey. The frequency of self-reported pain, its impact on the ability to perform daily activities, and health care use were measured. The differences between patients whose persistent pain continued and those whose pain resolved were assessed.

RESULTS

Five patients met criteria for pain at 3.4 years (range, 3.1-3.9 years) post-RCT, which was moderate in intensity, occurred for about 3 days in the preceding month, and kept 1 patient from usual activities. Additional health care was received by 4 of 5 patients whose pain continued compared with 7 of 22 patients whose pain resolved. A longer duration of preoperative pain and higher pain intensity and interference at 6 months were found among patients with pain chronification. Of 13 patients with specific diagnoses for the persistent pain derived at 65 ± 41 days (∼8 months) post-RCT, 10 improved regardless of the diagnosis or treatment, and 11 had a temporomandibular disorder and/or headache as comorbid diagnoses (6) or causes (6) of the persistent "tooth" pain.

CONCLUSIONS

Progression of persistent post-RCT pain occurred in 19% of patients. The majority (56%) of patients improved without additional interventions. Both the group that improved and the group that continued to experience pain had a mixture of odontogenic and nonodontogenic etiologies.

Acute and chronic pain in orofacial trauma patients

Trauma or injury to the dentition and supporting tissues is associated with pain and discomfort, as expected, that may present immediately, shortly afterwards, or within a few days. Pain is an essential response to injury because it allows the organism to develop avoidance behavior to potential threats and helps the organism to avoid usage of the injured organ during the healing process. Not only does external trauma induce pain, but also essential invasive dental procedures such as extractions, dental implant insertions, root canal treatments, and oral surgeries are accompanied by similar post-surgical (post-traumatic) pain. The pain intensity after trauma varies and does not always correlate with the extent of injury. Trauma to the orofacial region or the teeth may also indirectly affect and induce pain in other orofacial structures such as the masticatory muscles, the temporomandibular joint, and even the cervical spine. In most cases, the pain will resolve as soon as healing of the affected tissue occurs or after dental and routine palliative treatment. In a limited number of cases, the pain persists beyond healing and evolves into a chronic pain state. Chronic pain in the orofacial region presents diagnostic and management challenges. Misdiagnosis or delayed diagnosis of the oral chronic pain condition may lead to unnecessary dental treatment. This article will discuss diagnosis and treatment for acute and chronic pain as well as potential mechanisms involved in the undesirable transition from acute to chronic pain.

A cross-sectional examination of the profile of chiropractors recruited to the Australian Chiropractic Research Network (ACORN): a sustainable resource for future chiropractic research

OBJECTIVES

The Australian Chiropractic Research Network (ACORN) practice-based research network (PBRN) cohort was established to provide sustainable infrastructure necessary to address lack of rigorous investigation and to bridge the research-practice gap focused on chiropractic care for future years. This paper presents the profile of chiropractors recruited to the ACORN PBRN, a nationally representative sample of chiropractors working in Australia.

DESIGN

Cross-sectional analysis of baseline data from a cohort study of chiropractors in Australia.

SETTING

All registered chiropractors in Australia were invited to participate in the ACORN study and those who completed a practitioner questionnaire and consent form were included in the PBRN cohort.

PARTICIPANTS

A total of 1680 chiropractors (36%) were recruited to the cohort database. The average age of the PBRN participants is 41.9 years and 63% are male. The vast majority of the PBRN participants hold a university degree.

RESULTS

General practitioners were identified as the most popular referral source for chiropractic care and low back pain and neck pain were the most common conditions 'often' treated by the PBRN chiropractors. The chiropractors in this PBRN cohort rated high velocity, low amplitude adjustment/manipulation/mobilisation as the most commonly used technique/method and soft tissue therapy as the most frequently employed musculoskeletal intervention in their patient management.

CONCLUSIONS

The ACORN PBRN cohort constitutes the largest coverage of any single healthcare profession via a national voluntary PBRN providing a sustainable resource for future follow-up. The ACORN cohort provides opportunities for further nested substudies related to chiropractic care, chiropractors, their patients and a vast range of broader healthcare issues with a view to helping build a diverse but coordinated research programme and further research capacity building around Australian chiropractic.

Examining the Sensitivity and Specificity of 2 Screening Instruments: Odontogenic or Temporomandibular Disorder Pain?

INTRODUCTION

Two groups of patients with orofacial pains that are clinically important to distinguish from each other are patients with odontogenic pain and temporomandibular disorder (TMD) pain. The aim of this study was to determine the sensitivity and specificity of 2 screening instruments in distinguishing between patients with these types of pain.

METHODS

A convenience sample of patients seeking care at an endodontic clinic and an orofacial pain clinic were recruited. The 14-item dental pain questionnaire (DePaQ) was used to screen for odontogenic pain and the 6-item TMD screener was used to screen for TMD pain. Sensitivity and specificity calculations with 95% confidence intervals (CIs) were performed for both instruments, and thresholds/acceptability/performance was assessed using published guidelines.

RESULTS

Thirty-four patients with odontogenic pain and 37 patients with TMD pain were included in this study. The sensitivity of the DePaQ was 0.85 (95% CI, 0.69-0.95), and specificity was 0.11 (95% CI, 0.03-0.25). The sensitivity of the TMD screener was 0.92 (95% CI, 0.78-0.98), and specificity was 0.59 (95% CI, 0.41-0.75). The point estimates, a single value used to estimate the population parameter, for both the DePaQ and TMD screener were "acceptable" in identifying patients who had the pain condition in question (ie, sensitivity), whereas the point estimate for appropriately identifying patients who did not have the pain condition when they did not have it (ie, specificity) was "nonacceptable" for both.

CONCLUSIONS

The DePaQ and the TMD screener lack diagnostic accuracy for differentiating TMD from odontogenic tooth pain without adjunctive (clinical) investigation(s) or examination. However, the TMD screener has high sensitivity for identifying true positives (ie, TMD pain) and would therefore be useful as a screening instrument when one can definitively exclude odontogenic etiology for pain on clinical and radiographic grounds, for instance in endodontic practices. In this study, the negative predictive value was also high in the TMD screener, and, therefore, we can trust a negative result (ie, when the TMD screener is negative, we can be fairly certain the pain diagnosis is not TMD and rule out TMD).

Multiple-file vs. single-file endodontics in dental practice: a study in routine care

BACKGROUND

Little is known about the differences of rotary multiple file endodontic therapy and single-file reciprocating endodontic treatment under routine care conditions in dental practice. This multicenter study was performed to compare the outcome of multiple-file (MF) and single-file (SF) systems for primary root canal treatment under conditions of general dental practice regarding reduction of pain with a visual analogue scale (VAS 100), improvement of oral-health-related quality of life (OHRQoL) with the german short version of the oral health impact profile (OHIP-G-14) and the speed of root canal preparation.

MATERIALS AND METHODS

Ten general dental practitioners (GDPs) participated in the study as practitioner-investigators (PI). In the first five-month period of the study, the GDPs treated patients with MF systems. After that, the GDPs treated the patients in the second five-month period with a SF system (WaveOne). The GDPs documented the clinical findings at the beginning and on completion of treatment. The patients documented their pain and OHRQoL before the beginning and before completion of treatment.

RESULTS

A total of 599 patients were included in the evaluation. 280 patients were in the MF group, 319 were in the SF WaveOne group. In terms of pain reduction and improvement in OHIP-G-14, the improvement in both study groups (MF and SF) was very similar based on univariate analysis methods. Pain reduction was 34.4 (SD 33.7) VAS (MF) vs. 35.0 (SD 35.4) VAS (SF) (p = 0.840) and the improvement in OHIP-G-14 score was 9.4 (SD 10.3) (MF) vs. 8.5 (SD 10.2) (SF) (p = 0.365). The treatment time per root canal was 238.9 s (SD 206.2 s) (MF) vs. 146.8 sec. (SD 452.8 sec) (SF) (p = 0.003).

DISCUSSION

Regarding improvement of endodontic pain and OHRQoL measure with OHIP-G-14, there were no statistical significant differences between the SF und the MF systems. WaveOne-prepared root canals significantly faster than MF systems.

Frequency, impact, and predictors of persistent pain after root canal treatment: a national dental PBRN study

Root canal treatment (RCT) is commonly performed surgery and persistent pain is known to occur, but little is known about how these patients are affected by this pain. Although biopsychosocial mechanisms are thought to be associated with the development of such pain, similar to persistent pain after surgery in other body sites, little is known about the baseline predictors for persistent pain. We assessed the frequency of persistent pain 6 months after RCT, measured the impact this pain had on patients, and determined predictive factors for persistent tooth pain in a multicenter prospective cohort study conducted within the National Dental Practice-Based Research Network. Of 708 patients enrolled, 651 (91.9%) provided follow-up data, with 65 (10.0%) meeting criteria for pain 6 months after RCT. On average, these patients reported their pain as mild to moderate in intensity, present for approximately 10 days in the preceding month, and minimally interfered with daily activities. After adjusting for the type of dental practitioner and patient age, gender, and household income, pain duration over the week before RCT significantly increased the risk of developing persistent pain (odds ratio = 1.19 per 1 day increase in pain duration, 95% confidence interval: 1.07-1.33), whereas optimism about the procedure reduced the risk (odds ratio = 0.39, 95% confidence interval: 0.22-0.67). Our data suggest that persistent pain 6 months after RCT is fairly common, but generally does not have a large impact on those experiencing it. Furthermore, patient age and gender did not predict persistent pain, whereas preoperative pain duration and the patient's expectation did.

Validity of Preoperative Clinical Findings to Identify Dental Pulp Status: A National Dental Practice-Based Research Network Study

INTRODUCTION

Endodontic diagnostic tests are often used clinically to assess pulp status as a basis for the diagnosis and determination of whether root canal treatment (RCT) is indicated. Response to cold and pain on percussion are 2 common tests, yet their validity in identifying nonvital pulp in regular dental practice has not been reported.

METHODS

We assessed the validity of cold and percussion tests to identify nonvital pulp in teeth requiring RCT in a dental practice setting performed by 46 general dentists and 16 endodontists in the National Dental Practice-Based Research Network. The influence of patient-, tooth-, and dentist-related characteristics was investigated. Observed bleeding from the pulp chamber was the clinical reference. Sensitivity (SN), specificity (SP), overall test accuracy (TA), positive (PPV) and negative (NPV) predictive values, and likelihood and diagnostic odds ratios (LR+, LR-, dORs) were calculated for each single test and the combined cold and percussion tests.

RESULTS

Seven hundred eight patient teeth were included. Cold test showed high validity to identify a nonvital pulp status (SN = 89%, SP = 80%, TA = 84%, PPV = 81%, NPV = 88%, LR+ = 4.35, LR- = 0.14, dOR = 31.4), whereas pain on percussion had lower validity (SN = 72%, SP = 41%, TA = 56%, PPV = 54%, NPV = 60%, LR+ = 1.22, LR- = 0.69, dOR = 1.78). Combining the 2 tests did not increase validity, whereas preoperative pain, medication intake, patient age and sex, and dentist training level affected test validity significantly.

CONCLUSIONS

In regular dental practice, the cold test exhibits higher validity to discriminate between vital and nonvital pulp than the tooth percussion test.

Differential diagnoses for persistent pain after root canal treatment: a study in the National Dental Practice-based Research Network

INTRODUCTION

Pain present 6 months after root canal treatment (RCT) may be of odontogenic or nonodontogenic origin. This is important because treatments and prognoses are different; therefore, the aim of this study was to provide specific diagnoses of patients reporting pain 6 months after receiving initial orthograde RCT.

METHODS

We enrolled patients from the Midwest region of an existing prospective observational study of pain after RCT. Pain at 6 months was defined as ≥1 day of pain and average pain intensity of at least 1 of 10 over the preceding month. An endodontist and an orofacial pain practitioner independently performed clinical evaluations, which included periapical and cone-beam computed tomographic radiographs, to determine diagnoses.

RESULTS

Thirty-eight of the 354 eligible patients in the geographic area (11%) met the pain criteria, with 19 (50%) consenting to be clinically evaluated. As the sole reason for pain, 7 patients (37%) were given odontogenic diagnoses (4 involving the RCT tooth and 3 involving an adjacent tooth). Eight patients (42%) were given nonodontogenic pain diagnoses (7 from referred temporomandibular disorder pain and 1 from persistent dentoalveolar pain disorder). Two patients (11%) had both odontogenic and nonodontogenic diagnoses, whereas 2 (11%) no longer fit the pain criteria at the time of the clinical evaluation.

CONCLUSIONS

Patients reporting "tooth" pain 6 months after RCT had a nonodontogenic pain diagnosis accounting for some of this pain, with temporomandibular disorder being the most frequent nonodontogenic diagnosis. Dentists should have the necessary knowledge to differentiate between these diagnoses to adequately manage their patients.

Predicting severe pain after root canal therapy in the National Dental PBRN

Some patients experience severe pain following root canal therapy (RCT) despite advancements in care. We sought to identify factors, which can be measured preoperatively, that predict this negative outcome so that future research may focus on preemptive steps to reduce postoperative pain intensity. Sixty-two practitioners (46 general dentists and 16 endodontists) who are members of the National Dental Practice-Based Research Network enrolled patients receiving RCT for this prospective observational study. Baseline data collected from patients and dentists were obtained before treatment. Severe postoperative pain was defined based on a rating of ≥7 on a scale from 0 (no pain) to 10 (pain as bad as can be) for the worst pain intensity experienced during the preceding week, and this was collected 1 wk after treatment. Multiple logistic regression analyses were used to develop and validate the model. A total of 708 patients were enrolled during a 6-m period. Pain intensity data were collected 1 wk postoperatively from 652 patients (92.1%), with 19.5% (n = 127) reporting severe pain. In multivariable modeling, baseline factors predicting severe postoperative pain included current pain intensity (odds ratio [OR], 1.15; 95% confidence interval [CI], 1.07 to 1.25; P = 0.0003), number of days in the past week that the subject was kept from their usual activities due to pain (OR, 1.32; 95% CI, 1.13 to 1.55; P = 0.0005), pain made worse by stress (OR, 2.55; 95% CI, 1.22 to 5.35; P = 0.0130), and a diagnosis of symptomatic apical periodontitis (OR, 1.63; 95% CI, 1.01 to 2.64; P = 0.0452). Among the factors that did not contribute to predicting severe postoperative pain were the dentist's specialty training, the patient's age and sex, the type of tooth, the presence of swelling, or other pulpal and apical endodontic diagnoses. Factors measured preoperatively were found to predict severe postoperative pain following RCT. Practitioners could use this information to better inform patients about RCT outcomes and possibly use different treatment strategies to manage their patients (Clinicaltrials.gov NCT01201681).

Root canal therapy reduces multiple dimensions of pain: a national dental practice-based research network study

INTRODUCTION

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.

METHODS

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.

Clinical effectiveness of basic root canal treatment after 24 months: a randomized controlled trial

INTRODUCTION

The purpose of this study was to investigate the effectiveness of basic root canal treatment (BRT) with tactile working length determination in terms of radiographic and clinical outcome parameters compared with endodontic treatment with standard radiographic working length control.

METHODS

This was a clinical, multicenter, controlled, open-label trial to evaluate BRT effectiveness after 24 months. The primary end point was the apical extension score of the radiographic quality parameter of root canal fillings. The secondary radiographic end point was the periapical index, and the secondary clinical end point was tooth tender to percussion. The safety end point was tooth loss as a consequence of endodontic failure. Statistical analyses of binary and categoric data were calculated using cross tables and the chi-square test.

RESULTS

BRT with tactile working length determination compared with standard radiographic working length control did not significantly differ in terms of radiographic and clinical outcomes after 24 months. The apical extension of the root canal fillings and the periapical anatomic structures showed no significant differences according to radiographic analyses (P = .5). Corresponding results were found in clinical aspects of tooth tender to percussion (P = .6) and tooth loss (P = .7).

CONCLUSIONS

Tactile working length determination in BRT resulted in comparable treatment outcomes compared with standard endodontic treatment with radiographic working length control and turned out to be an accurate method in BRT.

Rational design and fabrication of a β-dicalcium silicate-based multifunctional cement with potential for root canal filling treatment

Gypsum-introduced, CaO-rich dicalcium silicate-based cements exhibit multifunctional physicochemical and biological properties and meet some challenging criteria in root canal therapy.