Role of (p)ppGpp in biofilm formation by Enterococcus faecalis.

Enterococcus faecalis strain OG1RF and its (p)ppGpp-deficient ΔrelA, ΔrelQ, and ΔrelA ΔrelQ mutants were grown in biofilms and evaluated for growth profiles, biofilm morphology, cell viability, and proteolytic activity. E. faecalis lacking (p)ppGpp had a diminished capacity to sustain biofilm formation over an extended period of time and expressed abundant proteolytic activity.

Conservative Management of Mature Permanent Teeth with Carious Pulp Exposure.

Vital pulp therapy (VPT) in mature permanent teeth with carious pulp exposure has been a matter of debate, with root canal therapy being the conventional standard of care. Previously reported negative outcomes for VPT in these teeth were based on data from studies that have used calcium hydroxide in direct pulp capping and partial and full pulpotomy. The introduction of hydraulic calcium silicate-based materials with sealing and bioactive potentials have opened a new era in VPT with more favorable results. Understanding the histopathology and histobacteriology of the cariously exposed pulp and the healing potential of the inflamed pulp could guide the decision-making process toward an ultraconservative management of these teeth. However, proper case selection, strict aseptic condition, capping material, and good coronal seal are crucial for long-term success.

Outcome assessment of orthodontic clear aligner vs fixed appliance treatment in a teenage population with mild malocclusions.

OBJECTIVE: To assess the efficacy and efficiency of treatment in adolescents presenting with mild malocclusions, comparing outcomes using clear aligners to fixed appliances. MATERIALS AND METHODS: Patients identified retrospectively and consecutively from one private practice had been treated with either clear aligners (Invisalign, Align Technology, Santa Clara, Calif) or fixed appliances (0.022 Damon, Ormco, Orange, Calif; n = 26/group). Assessments of occlusion were made using the American Board of Orthodontics Discrepancy Index (DI) for initial records and Cast-Radiograph Evaluation (CRE) for final records. Number of appointments, number of emergency visits, and overall treatment time were determined from chart reviews. Data were analyzed using Pearson's correlation, Wilcoxon rank tests, unpaired t-tests, and Chi-square tests, with significance set to P ≤ .05. RESULTS: Pretreatment, the aligner and fixed groups showed no significant difference in overall severity (DI: 11.9 ± 5.3 vs 11.6 ± 4.8) or in any individual DI category. Posttreatment scores showed finishes for the aligner group had fewer discrepancies from ideal relative to the fixed appliance group (CRE: 30.1 ± 8.3 vs 37.0 ± 9.3; P < .01). Patients treated with aligners had fewer appointments (13.7 ± 4.4 vs 19.3 ± 3.6; P < .0001), fewer emergency visits (0.8 ± 1.0 vs 3.6 ± 2.5; P < .0001), and shorter overall treatment time (16.9 ± 5.7 vs 23.4 ± 4.4 months; P < .0001). CONCLUSIONS: Outcomes for treatment of mild malocclusions in adolescents showed equivalent effectiveness of clear aligners compared to fixed appliances, with significantly improved results for clear aligner treatment in terms of tooth alignment, occlusal relations, and overjet. Assessment of the number of appointments, number of emergency visits, and overall treatment time showed better outcomes for treatment with clear aligners.

Accuracy of Presurgical Limited Field of View Cone-beam Computed Tomography in Predicting Intraoperative Buccal Cortical Bone.

INTRODUCTION: Limited field of view cone-beam computed tomography (LFOV CBCT) is the primary imaging modality recommended for treatment planning before endodontic microsurgery (EMS). Persistent apical periodontitis, often treated with EMS, results in changes in the buccal cortical plate that may detrimentally impact prognosis. The accuracy of a preoperative LFOV CBCT to predict intraoperative findings is unclear. METHODS: Electronic health records (EHRs) of EMS performed at 2 endodontic offices between 2016 and 2018 were reviewed retrospectively. EHR data extracted were documented for surgical findings of intact buccal cortical plate, fenestration, dehiscence, and height of remaining buccal collar of bone. Two calibrated, independent reviewers evaluated presurgical LFOV CBCTs in the multiplanar paraxial and parasagittal planes at 2 different reconstructed viewing plane thicknesses. Reviewer findings were compared with EHR documentation. Data were analyzed by using χ2, logistic regression, and multivariable analysis. Significance was set at P < .05. RESULTS: Within the 125 EMS cases included in the study, the EHR prevalence of intact buccal cortical plate was 49%, dehiscence 7%, and fenestration 44%. The imaging predictive value, whether it was negative (NPV) or positive (PPV), was higher when predicting presence of buccal bone (PPV of intact buccal cortical plate = 86.5%; NPV of dehiscence = 96%; NPV of fenestration = 89%). Sensitivity and specificity ranged from 80%-90%. Accuracy in prediction was high for all variables, exceeding 80%. Accuracy was not significantly influenced by reconstructed viewing slice thickness, viewing plane, or reviewer. CONCLUSION: Preoperative LFOV CBCT was highly discriminatory and accurately predicted intraoperative buccal cortical bone status, especially intact buccal cortical plate and fenestration.

Plasmid pAMS1-encoded, bacteriocin-related "Siblicide" in Enterococcus faecalis.

The Enterococcus faecalis class IIa bacteriocin MC4-1 encoded by the sex pheromone-responding, multiple-antibiotic resistance plasmid pAMS1 exhibits "siblicidal" (sibling-killing) activity under certain conditions. Stabs of plasmid-containing cells on solid medium containing lawns of bacteria of the same (plasmid-containing) strain give rise to zones of inhibition. If the plasmid-containing host also produces gelatinase, bacteriocin cannot be detected.

The impact of the Affordable Care Act on provision of endodontic services within a dental school setting in Oregon.

OBJECTIVES: In January 2014 implementation of the Medicaid expansion of the Affordable Care Act (EACA) in Oregon increased the number of children and adults qualifying for the Oregon Health Plan (OHP). Simultaneously, dental care benefits for adult Medicaid members were restored in Oregon after a period of noncoverage. This study evaluated the impact of these changes on the receipt of endodontic services in the Graduate Endodontic Clinic (GEC) at Oregon Health & Science University. METHODS: A retrospective electronic health records (EHRs) database review was conducted from July 2010 through June 2017, a seven-year period covering 3.5 years before (pre-EACA) and 3.5 years after (post-EACA) implementation of EACA. The number of completed anterior, premolar and molar non-surgical root canal therapies (NS-RCT) was retrieved from de-identified EHRs by targeting dental codes. Pre- and post-EACA frequencies were compared and analyzed by patient age [<21 years (children) versus adults], payer mix [OHP versus non-Medicaid (self-pay and private insurance)], and tooth type (anterior, premolar and molar) using Chi-square tests (P < 0.05). RESULTS: The number of procedures provided for patients covered by OHP post-EACA compared to pre-EACA was increased by 363 percent. There was an 18 percent decline in NS-RCT provided for non-OHP patients (P < 0.0001). Post-EACA increases in frequency applied to anterior, premolar, and molar NS-RCT (P < 0.0001), with the greatest increase in frequency post-EACA occurring for premolar NS-RCT procedures (666 percent). CONCLUSIONS: By eliminating barriers to care greater numbers of vulnerable people in Oregon sought and received endodontic services at the GEC.

Opioid-prescribing Practices in a Graduate Endodontic Clinic before and after Implementation of the Federal Schedule II Prescribing Mandate.

INTRODUCTION: Opioid prescriptions have the potential for misuse. In October 2014, the federal schedule II prescribing mandate reclassified hydrocodone combination products from schedule III to schedule II drugs that required a written prescription. The aim of this study was to evaluate the opioid-prescribing practices in a graduate endodontic clinic (GEC) before and after the mandate. METHODS: Electronic health records from all patients treated in the GEC from 2010 to 2018 were reviewed retrospectively for opioid prescribing, the date of prescription, and the Current Dental Terminology code. Where opioid prescribing was documented in the electronic health record, additional data were extracted about pulpal and periapical diagnosis, pain level, opioid type, and prescription details. Prescribing rates were calculated and analyzed by using chi-square, analysis of variance, logistic regression, and multivariable analysis. Significance was set at P < .05. RESULTS: Overall, 4851 patients underwent 7841 procedures; 92.2% of patients were never prescribed opioids. The remaining 380 patients underwent 420 procedures, and 509 prescriptions were provided. Prescribing rates were 7.5% (228/3021) before versus 4.0% (192/4820) after the mandate (P < .001). Hydrocodone combinations were the most prescribed opioid (77%, 392/509). Tramadol prescribing increased after the mandate (P = .023). Multivariable analysis showed significantly higher prescribing for apicoectomy procedures (P < .001). Preoperative pulpal and periapical diagnosis and pain level were not significantly associated with opioid prescribing. CONCLUSIONS: An overall reduction in opioid-prescribing rates occurred coincidentally with the 2014 federal mandate. The lack of correlation between prescribing and pain level highlighted the need for evidence-based rather than habitual prescribing protocols in the GEC.

The influence of root canal sealer on extended intracanal survival of Enterococcus faecalis with and without gelatinase production ability in obturated root canals.

Enterococcus faecalis can survive for extended periods in obturated root canals. In this study, the hypotheses tested were that long-term survival of E. faecalis is dependent on (1) the type of endodontic sealer and (2) the capacity for microbial gelatinase activity, a potential "virulence" trait identified previously in clinical isolates. Root canals of extracted human canines (n=95) were inoculated with either E. faecalis OG1RF or its gelatinase-negative mutant E. faecalis TX5128. After 48 hours of incubation at 37 degrees C, canals were obturated with gutta-percha and either the epoxy-resin-based AH-Plus (Dentsply, De Trey, Konstanz, Germany), the silicone-based RoekoSeal (Coltène/Whaledent, Langenau, Germany), or zinc oxide eugenol-based Roth's sealer (Root Canal Cement Type 801; Roth International Ltd, Chicago, IL). Access cavities were sealed. After 8 months of incubation at 37 degrees C, viable E. faecalis was recovered from more teeth sealed with RoekoSeal (95%) compared with AH-Plus (40%) (p=0.0004, Fisher's exact test) and Roth's sealer (45%) (p=0.0012, Fisher's exact test). In the RoekoSeal groups, viable counts of E. faecalis OG1RF were higher than E. faecalis TX5128 (p=0.03, Mann-Whitney U test) suggesting that gelatinase activity plays a role in long-term survival of E. faecalis in obturated root canals.

Biofilm formation of oral and endodontic Enterococcus faecalis.

Biofilms are complex aggregations of microorganisms attached to a surface. The formation of biofilms might facilitate certain survival and virulence characteristics under some situations. This study tested the hypothesis that the ability of Enterococcus faecalis to form biofilms is related to the source of the strains. E. faecalis strains recovered from root canals (n = 33), the oral cavity (n = 21), and non-oral/non-endodontic sources (n = 16) were studied. Biofilms were grown in tryptic soy broth in 96-well plates for 24 hours at 37 degrees C, fixed with Bouin's fixative, and stained with 1% crystal violet. Optical density at 570 nm (OD(570)) was measured by using a microtiter plate reader. Experiments were performed in quadruplicate on three occasions and mean OD(570) readings determined for each strain. There were no statistically significant differences between groups (p = 0.066, Kruskal-Wallis). Within the root canal and oral isolates there were no significant associations between biofilm formation and the presence of the virulence determinants asa, cylA, esp, and gelE.

Antibiotic Use in 2016 by Members of the American Association of Endodontists: Report of a National Survey.

INTRODUCTION: This study surveyed the antibiotic prescribing practices of endodontists, and data were compared with previous surveys conducted in 1994 and 1999. METHODS: A 17-question survey was sent via www.surveymonkey.com to 3000 active members of the American Association of Endodontists for responses about antibiotic prescribing practices and demographics. The data were analyzed using descriptive statistics, chi-square tests, and linear regression analyses. RESULTS: Six hundred eighty-six participants (22.86%) completed the survey. The most frequently prescribed antibiotics were amoxicillin (60.71%) followed by penicillin V (30.43%) and clindamycin for patients with allergies (95.4%). Respondents reported prescribing antibiotics for irreversible pulpitis with mild symptoms (1.75%), irreversible pulpitis with moderate symptoms (6.41%), necrotic pulp with symptomatic apical periodontitis (43.59%), chronic apical abscess without (10.50%) or with symptoms (29.74%), acute apical abscess (95.92%), avulsion (70.26%), endodontic surgery (41.69%), retreatment (silver point [23.76%] or gutta-percha [15.60%]), postoperative pain after instrumentation or obturation (12.39%), and perforation repair (5.98%). The type of practice (solo/group) and geographic region (Southeast) were significant predictors of increased antibiotic prescribing; 36.89% of respondents reported prescribing antibiotics that are not necessary, most commonly because of patient expectations. CONCLUSIONS: Since 1999, there has been a significant shift from prescribing penicillin V to amoxicillin as endodontists' first choice of antibiotic and a significant increase in the use of clindamycin for penicillin-allergic patients. Antibiotics continue to be prescribed in clinical situations for which they are typically not indicated, most commonly because of patient expectations. Regional differences in antibiotic prescribing practices by endodontists exist in the United States.

Nonsteroidal Anti-inflammatory Drugs for Managing Postoperative Endodontic Pain in Patients Who Present with Preoperative Pain: A Systematic Review and Meta-analysis.

INTRODUCTION: Nonsteroidal anti-inflammatory drugs (NSAIDs) have been commonly used to treat endodontic postoperative pain. The purpose of this study was to address the following Population, Intervention, Comparator, Outcome, Timing, Study design and setting question: in patients with preoperative pain who undergo initial orthograde endodontic treatment, what is the comparative efficacy of NSAIDS compared with non-narcotic analgesics or placebo in reducing postoperative pain and the incidence of adverse events. METHODS: Ovid MEDLINE (1946-December 15, 2015), the Cochrane Database of Systematic Reviews (2005-December 15, 2015), and the Cochrane Central Register of Controlled Trials (to December 15, 2015) were searched using included drugs, indications, and study designs as search terms. Hand searches in texts were also conducted. Two independent reviewers assessed eligibility for inclusion, extracted data, and assessed quality using the risk of bias tool. L'Abbe plots were used for qualitative review. Where applicable, meta-analysis was conducted on the pooled effect size (ES). RESULTS: Two thousand two hundred eighty-four studies were identified through the database searches; 405 full-text articles were assessed. Fifteen articles met the inclusion criteria; qualitative analysis revealed all studies had a moderate to high risk of bias. Ibuprofen was the most studied NSAID. The L'Abbe plots showed that NSAIDS are effective at relieving postoperative endodontic pain overall. Meta-analysis showed that ibuprofen 600 mg is more effective than placebo at 6 hours postoperatively (ES = 10.50, P = .037), and ibuprofen 600 mg + acetaminophen 1000 mg combination is more effective than placebo (ES = 34.89, P = .000) but not significantly different than ibuprofen (ES = 13.94, P = .317). Five studies reported patients experiencing adverse events such as drowsiness, dizziness, nausea, and emesis; 2 studies reported that patients experienced no adverse events. CONCLUSIONS: A combination of ibuprofen 600 mg and acetaminophen 1000 mg is more effective than placebo but not significantly different than ibuprofen 600 mg at 6 hours postoperatively. Ibuprofen 600 mg is more effective than placebo at 6 hours postoperatively; however, there are insufficient data to recommend the most effective NSAID, dose amount, or dose interval for the relief of postoperative endodontic pain of longer duration in patients with preoperative pain.

Coaggregation interactions between oral and endodontic Enterococcus faecalis and bacterial species isolated from persistent apical periodontitis.

Interactions between Enterococcus faecalis and other species found in root canal infections might be important for the development and persistence of periapical disease. The aim of this study was to investigate the coaggregation interactions between E. faecalis clinical isolates and species previously shown to survive and induce apical periodontitis in monkeys: Peptostreptococcus anaerobius, Prevotella oralis, Fusobacterium nucleatum, and Streptococcus anginosus. Intergeneric coaggregation assays were conducted in duplicate with observations scored immediately at 0 h, 1 h and 24 h after mixing of combinations of strains. All E. faecalis strains (n = 53) coaggregated with F. nucleatum; E. faecalis did not coaggregate with P. anaerobius or S. anginosus. One strain, E. faecalis E1, coaggregated with P. oralis, with aggregates visible at 1 h. Coaggregation interactions between E. faecalis and F. nucleatum observed in this study suggest a potential role for this combination in endodontic infections.

The influence of preparation size on the mechanical efficacy of root canal irrigation in vitro.

This study tested the hypothesis that the mechanical efficacy of irrigation in reducing intracanal bacteria is dependent on canal preparation size. Root canals of 30 extracted permanent cuspids were prepared consecutively to sizes 36, 60, and 77 at working length (WL) using ProFile 0.04 taper Series-29 files. Smear layer was removed and teeth autoclaved following completion of each instrumentation sequence. Root canals were inoculated with a 15-mul suspension (1x10 cells) of Pseudomonas fluorescens 5RL, a salicylate-inducible bioluminescent reporter strain. Bioluminescence was measured before inoculation (background), after inoculation and after irrigation with 6 ml of irrigant delivered 1 mm from WL using a 28G safety-ended needle. The percentage of bacteria remaining following irrigation was 26.95+/-9.71%, 10.46+/-5.87%, and 10.64+/-6.01% for sizes 36, 60, and 77, respectively (p<0.001; repeated-measures ANOVA), with no difference between sizes 60 and 77 (p>0.05; Tukeys). Irrigation 1 mm from WL was significantly less effective in canals prepared to size 36.

Does Articaine Provide an Advantage over Lidocaine in Patients with Symptomatic Irreversible Pulpitis? A Systematic Review and Meta-analysis.

INTRODUCTION: Achieving profound pulpal anesthesia can be difficult in patients with symptomatic irreversible pulpitis. This study provides a systematic review and meta-analysis to address the population, intervention, comparison, outcome (PICO) question: in adults with symptomatic irreversible pulpitis who are undergoing endodontic treatment, what is the comparative efficacy of articaine compared with lidocaine in reducing pain and incidence of adverse events? METHODS: A protocol was prepared and registered on PROSPERO. Electronic searches were conducted in MEDLINE, Scopus, Cochrane Library, and ClinicalTrials.gov by using strict inclusion and exclusion criteria. Two independent reviewers assessed eligibility for inclusion and quality. Weighted anesthesia success rates and 95% confidence intervals (CIs) were estimated and compared by using a random-effects model. RESULTS: Two hundred seventy-five studies were initially identified from the search; 10 double-blind, randomized clinical trials met the inclusion criteria. For combined studies, articaine was more likely than lidocaine to achieve successful anesthesia (odds ratio [OR], 2.21; 95% CI, 1.41-3.47; P = .0006; I(2) = 40%). Maxillary infiltration subgroup analysis showed no significant difference between articaine and lidocaine (OR, 3.99; 95% CI, 0.50-31.62; P = .19; I(2) = 59%). For combined mandibular anesthesia studies articaine was superior to lidocaine (OR, 2.20; 95% CI, 1.40-3.44; P = .0006; I(2) = 30%), with further subgroup analysis showing no difference for mandibular block anesthesia (OR, 1.44; 95% CI, 0.87-2.38; P = .16; I(2) = 0%). When used for supplemental infiltration after successful mandibular block anesthesia, articaine was significantly more effective than lidocaine (OR, 3.55; 95% CI, 1.97-6.39; P < .0001; I(2) = 9%). There were no reports of adverse events. CONCLUSIONS: This systematic review of double-blind, randomized clinical trials provides level 1 evidence to support the use of articaine for patients with symptomatic irreversible pulpitis. There is a significant advantage to using articaine over lidocaine for supplementary infiltration after mandibular block anesthesia but no advantage when used for mandibular block anesthesia alone or for maxillary infiltration.

A survey for endodontists in today's economy: exploring the current state of endodontics as a profession and the relationship between endodontists and their referral base.

INTRODUCTION: The purpose of this study was to assess the perceptions, referral trends, and practice patterns of practicing endodontists in the United States and any effect the recent economy may have had on these. METHODS: A 24-question survey was formulated and sent via www.surveymonkey.com to 3255 active members of the American Association of Endodontists. Overall, 875 participants completed the survey, a response rate of 26.9%. RESULTS: The average number of treatment cases per day was 5.7. Average work hours per week were 34.3 for men and 30.7 for women (P < .05). Among all treatment cases, 46% were nonsurgical retreatment, and 7.2% were apical surgical procedures. Procedural misadventure accounted for 10.8% of all treatment cases, with the most common referral reason being unable to locate canals (75.0%) followed by separated instruments (15.3%). Of all respondents, 49.9% performed regenerative endodontic procedures, and 7.7% placed implants. Among endodontists who practice in urban areas, 69.7% believed there were too many endodontists, and 50% have delayed their retirement plans because of recent economic impact, compared with their suburban and rural counterparts at 66.1% and 38%, 25.9% and 33.1%, respectively (P < .05). Fifty-nine percent of respondents were optimistic about the future of endodontics as a specialty, but those who have practiced more than 20 years were more pessimistic than those with less experience (P < .05). CONCLUSIONS: Recent economic impacts appear to have had an effect on the perceptions of active endodontists regarding practice success, the future of the specialty, and their retirement plans. Those who have been in practice longest (>20 years), practice in urban settings, and practice in a solo environment are most significantly affected.