Hemicrania continua: Case series presenting in an orofacial pain clinic.

AIM OF INVESTIGATION: Hemicrania continua (HC) is an uncommon primary headache and little is known of the characteristics of such patients managed in an orofacial pain setting. This study provides clinical features of HC, its association with other disorders, and treatment outcomes of patients managed in the TMD and Orofacial Pain Clinic at the University of Minnesota. METHODS: A retrospective review of patient records was undertaken. Inclusion criteria were a diagnosis of HC and confirmation at follow-up. RESULTS: Six of the 1617 new patients seen between 2015 and 2017 met the selection criteria. Four patients presented with "facial pain", one with "toothache" and one with "jaw pain". All were female with mean age 55 ± 10.5 years (range = 41-69). Headache characteristics included unilateral (R:L = 1:1) pain of moderate intensity with severe exacerbations in the distribution of V1 (1/6), V1 + V2 (3/6) and V1 + V2 + V3 (2/6). Lacrimation and photophobia were the most common associated symptoms. Patient presentations were complicated by multiple medical and comorbid diagnoses. All were diagnosed with temporomandibular disorder (TMD). Indomethacin alone was sufficient for adequate headache control in 2/6 patients with several add-on medications providing sustained pain relief. CONCLUSIONS: Comorbid pain conditions can be expected in patients with HC presenting to orofacial pain clinics. Symptom presentation varies, and multimodal treatment approach is necessary for success.

Differential Diagnoses for Persistent Pain Following Root Canal Treatment: A Study in the National Dental PBRN.

INTRODUCTION: Pain present six months following root canal treatment (RCT) may be either of odontogenic or non-odontogenic 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 six 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 six months was defined as ≥ 1 day of pain and average pain intensity of at least 1/10 over the preceding month. An endodontist and an orofacial pain practitioner independently performed clinical evaluations, which included periapical and cone-beam computed tomograph (CT) radiographs, to determine diagnoses. RESULTS: Thirty-eight out 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, 3 involving an adjacent tooth). Eight patients (42%) were given non-odontogenic pain diagnoses (7 from referred temporomandibular disorder [TMD] pain, 1 from persistent dentoalveolar pain disorder [PDAP]). Two patients (11%) had both odontogenic and non-odontogenic diagnoses, while 2 (11%) no longer fit the pain criteria at the time of the clinical evaluation. CONCLUSION: Patients reporting "tooth" pain 6 months following RCT had a non-odontogenic pain diagnosis accounting for some of this pain, with TMD being the most frequent non-odontogenic diagnosis. Dentists should have the necessary knowledge to differentiate between these diagnoses to adequately manage their patients.

Evidence-based clinical practice guideline for the pharmacologic management of acute dental pain in adolescents, adults, and older adults: A report from the American Dental Association Science and Research Institute, the University of Pittsburgh, and the University of Pennsylvania.

BACKGROUND: A panel convened by the American Dental Association Science and Research Institute, the University of Pittsburgh, and the University of Pennsylvania conducted systematic reviews and meta-analyses and formulated evidence-based recommendations for the pharmacologic management of acute dental pain after simple and surgical tooth extraction(s) and for the temporary management (ie, definitive dental treatment not immediately available) of toothache associated with pulp and periapical diseases in adolescents, adults, and older adults. TYPES OF STUDIES REVIEWED: The panel conducted 4 systematic reviews to determine the effect of opioid and nonopioid analgesics, local anesthetics, corticosteroids, and topical anesthetics on acute dental pain. The panel used the Grading of Recommendations, Assessment, Development and Evaluation approach to assess the certainty of the evidence and the Grading of Recommendations, Assessment, Development and Evaluation Evidence-to-Decision Framework to formulate recommendations. RESULTS: The panel formulated recommendations and good practice statements using the best available evidence. There is a beneficial net balance favoring the use of nonopioid medications compared with opioid medications. In particular, nonsteroidal anti-inflammatory drugs alone or in combination with acetaminophen likely provide superior pain relief with a more favorable safety profile than opioids. CONCLUSIONS AND PRACTICAL IMPLICATIONS: Nonopioid medications are first-line therapy for managing acute dental pain after tooth extraction(s) and the temporary management of toothache. The use of opioids should be reserved for clinical situations when the first-line therapy is insufficient to reduce pain or there is contraindication of nonsteroidal anti-inflammatory drugs. Clinicians should avoid the routine use of just-in-case prescribing of opioids and should exert extreme caution when prescribing opioids to adolescents and young adults.

Evidence-based clinical practice guideline for the pharmacologic management of acute dental pain in children: A report from the American Dental Association Science and Research Institute, the University of Pittsburgh School of Dental Medicine, and the Center for Integrative Global Oral Health at the University of Pennsylvania.

BACKGROUND: A guideline panel convened by the American Dental Association Council on Scientific Affairs, American Dental Association Science and Research Institute, University of Pittsburgh School of Dental Medicine, and Center for Integrative Global Oral Health at the University of Pennsylvania conducted a systematic review and meta-analyses and formulated evidence-based recommendations for the pharmacologic management of acute dental pain after 1 or more simple and surgical tooth extractions and the temporary management of toothache (that is, when definitive dental treatment not immediately available) associated with pulp and furcation or periapical diseases in children (< 12 years). TYPES OF STUDIES REVIEWED: The authors conducted a systematic review to determine the effect of analgesics and corticosteroids in managing acute dental pain. They used the Grading of Recommendations Assessment, Development and Evaluation approach to assess the certainty of the evidence and the Grading of Recommendations Assessment, Development and Evaluation Evidence to Decision framework to formulate recommendations. RESULTS: The panel formulated 7 recommendations and 5 good practice statements across conditions. There is a small beneficial net balance favoring the use of nonsteroidal anti-inflammatory drugs alone or in combination with acetaminophen compared with not providing analgesic therapy. There is no available evidence regarding the effect of corticosteroids on acute pain after surgical tooth extractions in children. CONCLUSIONS AND PRACTICAL IMPLICATIONS: Nonopioid medications, specifically nonsteroidal anti-inflammatory drugs like ibuprofen and naproxen alone or in combination with acetaminophen, are recommended for managing acute dental pain after 1 or more tooth extractions (that is, simple and surgical) and the temporary management of toothache in children (conditional recommendation, very low certainty). According to the US Food and Drug Administration, the use of codeine and tramadol in children for managing acute pain is contraindicated.

Postoperative Pain: An Analysis on Evolution of Research in Half-Century.

INTRODUCTION: Examining the evolution of research parameters helps scientists to discover the well-developed and neglected aspects of knowledge. Pain after root canal treatment is a health problem affecting millions of patients. Research in this field has a meaningful impact on quality of lives. The aim of this study was to analyze the evolution of research on postoperative pain over the past 50 years. METHODS: Electronic searches were performed in Scopus and MEDLINE databases to identify studies on pain after nonsurgical root canal treatments/retreatments. The full texts of eligible articles were reviewed to determine the study category and to extract and analyze the methodological variables. A series of statistical analyses were performed to determine the trend of publications based on the variable of interest over time. RESULTS: Four hundred twenty-four articles were included. There was a positive trend for systematic reviews, studies with sample size <200, studies on single-visit treatment, and clinical trials on instrumentation and adjunct treatments (P < .05). There was a negative trend for the use of numeric rating scales, studies on multiple-visit treatments, clinical trials on medication/medicament, and studies on pain in maxillary incisors (P < .05). No trend was observed based on pulpal diagnosis or for studies with longer observation periods (>8 weeks) (P > .05). CONCLUSIONS: A paradigm shift is needed toward clinical studies with larger sample sizes, longer observation periods, and more focus on pulpal diagnoses associated with higher rates of postoperative pain. There is a need to view postoperative pain as an important patient-centered outcome and to develop and disseminate standard reporting guidelines for future studies.

New International Classification of Orofacial Pain: What Is in It For Endodontists?

Pain is a common symptom in endodontic conditions, but differential diagnostic procedures are often needed to exclude other pain origins. Thus, general dentists and endodontists need to be aware of alternative painful orofacial conditions and be able to identify them. The new International Classification of Orofacial Pain (ICOP) is the first comprehensive classification that uniquely deals with orofacial pain. The ICOP is a hierarchical classification modeled on the International Classification of Headache Disorders and covers pain in dentoalveolar and anatomically related tissues, muscle pain, temporomandibular joint pain, neuropathic pain affecting cranial nerves, pain resembling primary headaches, and idiopathic pain in the orofacial region. A description of each condition is given, and structured diagnostic criteria for each condition are proposed based on research data when available. This narrative review aims (1) to give an overview and brief explanation of the ICOP system, (2) to describe and give examples of how it can be of use to general dentists and endodontists with special attention to differential diagnosis of tooth pain, and (3) to highlight how endodontic research can contribute to validation and improvement of the classification. A comparison to other classification and diagnostic systems is also included.

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.

Interexaminer Agreement in the Radiologic Identification of Apical Periodontitis/Rarefying Osteitis in the National Dental Practice-Based Research Network PREDICT Endodontic Study.

INTRODUCTION: Periapical images are routinely made in endodontics to support diagnosis and treatment decisions, but conventional imaging may not readily demonstrate inflammatory changes. This study aims to quantify disagreement in the radiologic interpretation of apical periodontitis/rarefying osteitis between 2 expert examiners and to determine if differences exist based on anatomic location. METHODS: We used 1717 pretreatment periapical images made before orthograde endodontic treatment as part of the Predicting Outcomes of Root Canal Treatment (PREDICT) study conducted within the National Dental Practice-Based Research Network. Periapical changes were assessed independently by 2 board-certified specialists, an oral and maxillofacial radiologist and an endodontist, blinded to other clinical information. If the examiners disagreed about whether a diagnosis of apical periodontitis/rarefying osteitis was justified, an adjudication was made by a third examiner. RESULTS: The overall prevalence of this radiologic diagnosis in the periapical images was 55%, and interexaminer agreement measured with the Cohen kappa statistic was calculated to be 0.56 (95% confidence interval, 0.52-0.60). Diagnostic disagreements between the 2 examiners occurred for 377 teeth (22%), with disagreements more frequent for jaw location (P = .038) and tooth type (P = .021). Differences between root number (P = .058) and jaw location and tooth groups (P = .069) were found not to be statistically significant. CONCLUSIONS: The variability of diagnostic disagreements across anatomic location and tooth type may reflect the inability of periapical images to reveal bone changes masked by the complexity and density of overlying anatomic structures, a limitation that could potentially be overcome with the use of 3-dimensional imaging.

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.

Accuracy and Reliability of Root Crack and Fracture Detection in Teeth Using Magnetic Resonance Imaging.

INTRODUCTION: Magnetic resonance imaging (MRI) has the potential to aid in determining the presence and extent of cracks/fractures in teeth because of better contrast without ionizing radiation. The objectives were to develop MRI criteria for root crack/fracture identification and to establish reliability and accuracy in their detection. METHODS: MRI-based criteria for crack/fracture appearance was developed by an MRI physicist and a panel of 6 dentists. Twenty-nine human adult teeth previously extracted after a clinical diagnosis of a root crack/fracture were frequency matched to 29 controls. Samples were scanned using an in vivo MRI protocol and the reference standard (ie, ex vivo limited field of view cone-beam computed tomographic [CBCT] imaging). A blinded, 4-member panel evaluated the images with a proportion randomly retested to establish intrarater reliability. Overall observer agreement, sensitivity, and specificity were computed for each imaging modality. RESULTS: Subjectively, MRI has increased crack/fracture contrast and is less prone to artifacts from radiodense materials relative to CBCT imaging. Intrarater reliability for MRI was fair to excellent (κ = 0.38-1.00), and for CBCT imaging, it was moderate to excellent (κ = 0.66-1.00). Sensitivity for MRI was 0.59 (95% confidence interval [CI], 0.39-0.76; P = .46), and for CBCT imaging, it was 0.59 (95% CI, 0.59-0.76; P = .46). Specificity for MRI was 0.83 (95% CI, 0.64-0.94; P < .01), and for CBCT imaging, it was 0.90 (95% CI, 0.73-0.98; P < .01). CONCLUSIONS: Despite advantages of increased contrast and the absence of artifacts from radiodense materials in MRI, comparable measures of sensitivity and specificity (to limited field of view CBCT imaging) suggest MRI quality improvements are needed, specifically in image acquisition and postprocessing parameters. Given the early stage of technology development, there may be a use for MRI in detecting cracks/fractures in teeth.

Retrospective cross sectional comparison of initial nonsurgical endodontic treatment and single-tooth implants.

Initial root canal treatment and the replacement of a single tooth with an implant are both viable treatment options, but various success rates have been reported for each treatment modality. This retrospective study compared 196 implant restorations and 196 matched initial nonsurgical root canal treatment (NSRCT) teeth in patients for four possible outcomes: success, survival, survival with subsequent treatment intervention and failure. Cross classifications/tabulations were analyzed using Pearson's chi2 test for association of the two classifications (endodontic vs implant and outcome). Polytomous regression with likelihood ratio tests were used in testing association with tooth location and outcome. Outcomes were as follows for implants and NSRCT respectively: success 73.5% and 82.1%; survival with no intervention 2.6% and 8.2%; survival with intervention 17.9% and 3.6%; and failure 6.1% and 6.1%. Location of the restoration in the mouth did not affect outcome. This study suggests that restored endodontically treated teeth and single tooth implant restorations have similar failure rates, although the implant group showed a longer average and median time to function and a higher incidence of postoperative complications requiring subsequent treatment intervention.

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).

Initial accuracy assessment of the modified S-LANSS for the detection of neuropathic orofacial pain conditions.

OBJECTIVE: To evaluate the accuracy of a questionnaire modified for the identification of intraoral pain with neuropathic characteristics in a clinical orofacial pain sample population. METHOD AND MATERIALS: 136 participants with at least one of four orofacial pain diagnoses (temporomandibular disorders [TMD, n = 41], acute dental pain [ADP, n = 41], trigeminal neuralgia [TN, n = 19], persistent dentoalveolar pain disorder [PDAP, n = 14]) and a group of pain-free controls (n = 21) completed the modified S-LANSS, a previously adapted version of the original questionnaire devised to detected patients suffering from intraoral pain with neuropathic characteristics. Psychometric properties (sensitivity, specificity, positive predictive value [PPV], negative predictive value [NPV]) were calculated in two analyses with two different thresholds: (1) Detection of pain with neuropathic characteristics: PDAP + TN were considered positive, and TMD + ADP + controls were considered negative per gold standard (expert opinion). (2) Detection of PDAP: PDAP was considered positive and TMD + ADP were considered negative per gold standard. For both analyses, target values for adequate sensitivity and specificity were defined as ≥ 80%. RESULTS: For detection of orofacial pain with neuropathic characteristics (PDAP + TN), the modified S-LANSS presented with the most optimistic threshold sensitivity of 52% (95% confidence interval [CI], 34-69), specificity of 70% (95% CI, 60-79), PPV of 35% (95% CI, 22-51), and NPV of 82% (95% CI, 72-89). For detection of PDAP only, with the most optimistic threshold sensitivity was 64% (95% CI, 35-87), specificity 63% (95% CI, 52-74), PPV 23% (95% CI, 11-39) and NPV 91% (95% CI, 81-97). CONCLUSION: Based on a priori defined criteria, the modified S-LANSS did not show adequate accuracy to detect intraoral pain with neuropathic characteristics in a clinical orofacial pain sample.

Retrospective cross sectional comparison of initial nonsurgical endodontic treatment and single-tooth implants.

Initial root canal treatment and the replacement of a single tooth with implants are both viable treatment options, but various success rates have been reported for each treatment modality. This study compared 196 implant restorations and 196 matched initial nonsurgical root canal treatment (NSRCT) teeth in patients for four possible outcomes- success, survival, survival with subsequent treatment intervention and failure. Cross classifications/tabulations were analyzed using Pearson's chi(2) test for association of the two classifications (endo vs. implant and outcome). Polytomous regression with likelihood ratio tests were used in testing association with tooth location and outcome. Outcomes were as follows for implants and NSRCT outcomes, respectively: success 73.5% and 82.1%; survival with no intervention 2.6% and 8.2%; survival with intervention 17.9% and 3.6%; and failure 6.1% and 6.1%. Location of the restoration in the mouth did not affect outcome. This study suggests that restored endodontically treated teeth and single-tooth implant restorations have similar failure rates, although the implant group showed a longer average and median time to function and a higher incidence of postoperative complications requiring subsequent treatment intervention.

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.

Techniques and materials used by general dentists during endodontic treatment procedures: Findings from The National Dental Practice-Based Research Network.

BACKGROUND: Little is known about which materials and techniques general dentists (GDs) use during endodontic procedures. The objectives were to quantify GDs' use of specific endodontic tools, quantify inappropriate use, and ascertain whether inappropriate use is associated with GDs' practice characteristics. METHODS: GDs in The National Dental Practice-Based Research Network reported in a questionnaire materials and techniques they use during endodontic procedures. RESULTS: Among eligible GDs, 1,490 (87%) participated. Most (93%; n = 1,383) used sodium hypochlorite to irrigate. The most commonly used sealers were zinc oxide eugenol (43%) and resin (40%), followed by calcium hydroxide (26%). Most (62%; n = 920) used a compaction obturation technique; 36% (n = 534) used a carrier-based method. Most (96%; n = 1,423) used gutta-percha as a filler; 5% used paste fillers. Few used irrigants (n = 46), techniques (n = 49), or fillers (n = 10) that investigators classified as inappropriate. CONCLUSIONS: GDs use a broad range of endodontic techniques and materials, often adapting to newer technologies as they become available. Few GDs use tools that the investigators classified as inappropriate. PRACTICAL IMPLICATIONS: GDs use many types of endodontic techniques and materials, but only a small percentage of them are inappropriate.

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.

Effects of pre-emptive morphine, ibuprofen or local anesthetic on fos expression in the spinal trigeminal nucleus following tooth pulp exposure in the rat.

In the present study, we used Fos expression as an index of nociceptive input to the spinal trigeminal nucleus after exposure of the coronal pulp tissue of maxillary right first molars and examined the effects of pretreatment with an opioid, a nonsteroidal anti-inflammatory drug or a local anesthetic before pulp exposure. Exposure of the tooth pulp produced a significant increase in Fos-like immunoreactivity in the superficial laminae of subnucleus caudalis; pretreatment with a control infiltration injection of saline directly above the maxillary molar 30 min before pulp exposure had no effect on Fos expression. Pretreatment with morphine 30 min before pulp exposure dose-dependently (2.5, 5, and 10 mg/kg subcutaneously) reduced Fos expression in subnucleus caudalis whereas pretreatment with ibuprofen (10-100 mg/kg subcutaneously) did not significantly affect Fos expression. Local anesthetic pretreatment was effective in reducing Fos expression only for the long acting bupivacaine; lidocaine without and with epinephrine (1:100,000) failed to significantly affect Fos expression. These results suggest that pre-emptive opioid treatment can decrease postoperative central nervous system changes associated with tooth pulp injury, and therefore, may decrease postoperative pain. Given the effects of local anesthetic on Fos expression, a combination of long acting local anesthetic with pre-emptive opioid would likely be most efficacious in decreasing postoperative dental pain.