Comparison of IL-1ß, TNF-α, hBD-2, and hBD-3 Expression in the Dental Pulp of Smokers Versus Nonsmokers.

INTRODUCTION: To date, the endodontic literature lacks research on the effect of smoking on cytokine and defensin expression in the dental pulp. Therefore, the aim of this study was to investigate the expression of interleukin (IL)-1ß, tumor necrosis factor (TNF)-α, human beta defensin (hBD)-2 and hBD-3 in the dental pulp of smokers and compare them with nonsmokers. We hypothesized that cytokine and defensin expression would be reduced in smokers as compared with nonsmokers. METHODS: Thirty-two smokers and 37 nonsmokers with endodontic pulpal diagnoses of normal, symptomatic irreversible pulpitis and asymptomatic irreversible pulpitis were included in this cross-sectional study. Samples from pulp chambers were collected and stored in phosphate-buffered saline at -80°C. Luminex was used to measure IL-1ß and TNF-α levels. The levels of hBD-2 and hBD-3 were measured using enzyme-linked immunosorbent assay. Marker levels were normalized to protein concentrations and data were analyzed using Kruskal-Wallis test, Mann-Whitney U test, and 2-way analysis of variance (α = 0.05). RESULTS: Pulpal concentrations of TNF-α and hBD-2 were significantly lower among smokers (P < .01), whereas no significant difference was observed for IL-1ß, or hBD-3. Two-way analysis of covariance revealed that smoking status (P < .001), not endodontic diagnosis (pulpal status), significantly affected TNF-α and hBD-2 levels. CONCLUSIONS: This study reported that smokers are immunologically deficient in TNF-α and hBD-2, suggesting that dental pulps of smokers possess limited defense mechanisms, affecting their endodontic prognosis and indicating a cause for their reported inferior outcome.

The Effect of Various Concentrations of Nitrous Oxide and Oxygen on the Hypersensitive Gag Reflex.

The purpose of this study was to compare the effectiveness of various concentrations of N2O/O2 on obtunding a hypersensitive gag reflex. We hypothesized that the administration of nitrous oxide and oxygen would obtund a hypersensitive gag reflex enough to allow a patient to tolerate the placement and holding of a digital x-ray sensor long enough to obtain a dental radiograph. Volunteers claiming to have a hypersensitive gag reflex were first screened to validate their claim and then tested by placing a size 2 digital x-ray sensor in the position for a periapical radiograph of the right mandibular molar area and holding it in place for 10 seconds. Subjects were first tested using room air only, then 30%, 50%, or 70% nitrous oxide until they were able to tolerate the sensor without gagging or discomfort. A visual analog scale was used for subjective responses, and other statistical tests were used to analyze the results. We found that for some subjects, 30% nitrous oxide was sufficient; for others, 50% was needed; and for the remainder of the subjects, 70% was sufficient to tolerate the test. Using a combination of 70% nitrous oxide and 30% oxygen allowed all patients claiming to have a hypersensitive gag reflex to tolerate the placement and holding of a digital x-ray sensor long enough to take a periapical radiograph.

Eight-Year Retrospective Study of the Critical Time Lapse between Root Canal Completion and Crown Placement: Its Influence on the Survival of Endodontically Treated Teeth.

INTRODUCTION: The purpose of this study was to investigate the effects of factors associated with various coronal restorative modalities after root canal treatment (RCT) on the survival of endodontically treated teeth (ETT) and to assess the effect of time lapse between RCT and crown placement after RCT to form a tooth loss hazard model. METHODS: Computerized analysis was performed for all patients who received posterior RCT from 2008 to 2016 in the graduate endodontic department. Data collected included dates of RCT, type of post-endodontic restoration, and time of extraction if extracted. Teeth that received crown after RCT were also divided into 2 groups: receiving crown before 4 months and after 4 months after RCT. Data were analyzed by using Kaplan-Meier log-rank test and Cox regression model (α = 0.05) by using SPPS Statistic 21. RESULTS: Type of restoration after RCT significantly affected the survival of ETT (P = .001). ETT that received composite/amalgam buildup restorations were 2.29 times more likely to be extracted compared with ETT that received crown (hazard ratio, 2.29; confidence interval, 1.29-4.06; P = .005). Time of crown placement after RCT was also significantly correlated with survival rate of ETT (P = .001). Teeth that received crown 4 months after RCT were almost 3 times more likely to get extracted compared with teeth that received crown within 4 months of RCT (hazard ratio, 3.38; confidence interval, 1.56-6.33; P = .002). CONCLUSIONS: Patients may benefit by maintaining their natural dentition by timely placement of crown after RCT, which otherwise may have been extracted and replaced by implant because of any delay in crown placement.

Determination of mutagenicity of the precipitate formed by sodium hypochlorite and chlorhexidine using the Ames test.

The aim of this study was to determine the direct mutagenic potential of any precipitate formed by combining sodium hypochlorite (NaOCl) and chlorhexidine (CHX). The precipitates formed by NaOCl and CHX were dissolved in 100% dimethyl sulfoxide and cultured with mutant Salmonella Typhimurium strains. The cells were observed for reverse mutation. The numbers of positive/mutated wells were statistically compared with those in the background plates using the two-sample proportion independent t-test. The precipitates were not found to be significantly more mutagenic than the background plates. Within the limitations of this study, the results suggest that the precipitates formed when sodium hypochlorite and chlorhexidine contact did not show mutagenic (and are therefore carcinogenic) potential.

Are more endodontic consultations needed in dental school clinic settings? A study of treatment decisions at one school.

With no previous studies of the occurrence of interdisciplinary consultations for tooth extraction in a dental school clinic setting, the aim of this cross-sectional descriptive investigation was to measure and compare the consultation process that occurred among departments at one U.S. dental school for making treatment decisions on tooth extraction. A comprehensive computerized retrieval (Crystal Reports) was used to identify and gather data from patient records from July 1, 2007, to July 1, 2011. Treatment plans and progress notes were analyzed to determine why each tooth had been extracted and which department had recommended the extraction. Results showed that the clinical departments involved in treatment planning decisions were the DMD dental student clinic, Department of Periodontics, and Department of Endodontics. The narrative records of 227 patients who had 516 teeth extracted were examined. About three-fourths (73.26%) of the extracted teeth were extracted based on the recommendation of only one department. Of these extracted teeth, 22.0% (n=114) were previously endodontically treated, and only four were recommended for endodontic consultation prior to extraction. The study found that most extractions were performed without specialty consultations and that the Department of Endodontics was consulted the least of all departments. To foster interdisciplinary collaboration in dental school clinics and help students develop expertise in such collaborations, more specialty consultations are needed for teeth that are treatment planned for extraction in order to preclude needless extraction of potentially salvageable teeth. Doing so will provide benefits for both patient care and students' education.

Assessment of patients' awareness and factors influencing patients' demands for sedation in endodontics.

INTRODUCTION: Endodontic therapy is perceived by many as a procedure to be feared. Many studies have reported that fear and anxiety are major deterrents to seeking dental care in general, but only a few deal with the use of sedation in endodontic therapies. The purpose of this study was to assess patients' awareness of and factors influencing the potential demand for sedation in endodontics. We hypothesized that there is an association between demographic factors and the demand for sedation in endodontics. METHODS: A survey consisting of 24 questions was given to patients 18 years and older who presented to the graduate endodontic clinic. Results were collected and statistically analyzed. RESULTS: Thirty-six percent of patients reported that their perception of sedation was being put to sleep, and 27% perceived it as related to or reducing pain. Concerns associated with endodontic therapy were the fear of pain (35%), fear of needles (16%), difficulty getting numb (10%), and anxiety (7%). The 2 major demographic factors that influenced the demand for sedation were cost and the level of anxiety (P < .05). Fifty-one percent showed a positive interest in sedation for endodontic therapy if the option of sedation was available. CONCLUSIONS: The demand for sedation in endodontics is high. Patients' understanding of sedation varies. More patients would consider having endodontic procedures if sedation was available. The provision of sedation by endodontists could result in more patients accepting endodontic therapies.

The critical time-lapse between various restoration placements and subsequent endodontic intervention.

INTRODUCTION: The purpose of this study was 2-fold: (1) to investigate the critical time-lapse of endodontic intervention subsequent to various restorations and tooth surfaces and (2) to assess and compare the risk factors associated with the restorations, tooth surfaces, and endodontic treatment. METHODS: A comprehensive computerized analysis of all dental school patients at the Case Western Reserve University School of Dental Medicine who received restorations from 2008-2013 was obtained. Inclusion and exclusion criteria were applied. The sample size was limited to teeth with endodontic treatment completed by the endodontic postgraduate dental clinic. Data collected included restoration type, restored tooth surfaces, tooth type, and the dates of restoration and subsequent endodontic treatment. A 2-sample paired t test (95% confidence interval, P < .05) and pair-wise comparison with Bonferroni corrections were implemented. RESULTS: The mean time between restoration placement and resultant endodontic intervention was 270 days, with a mean difference of 247-294 days (P < .0001). Further analysis revealed composite resin was 1.91 times more likely than amalgam and 5.69 times more likely than crowns to cause resultant endodontic intervention. Teeth with 2 or more restorative surfaces required endodontic intervention (P < .001). CONCLUSIONS: Of the patients who required endodontic treatment after restoration placement, the critical time-lapse was 9 months. Composite restorations and teeth with 2 or more restorative surfaces were significantly associated with endodontic treatment. From the results of the current study, we recommended that all dental practitioners should perform a thorough endodontic evaluation and diagnosis before, during, and after all restorative procedures.

An analysis of moderate sedation protocols used in dental specialty programs: a retrospective observational study.

INTRODUCTION: Pain and anxiety control is critical in dental practice. Moderate sedation is a useful adjunct in managing a variety of conditions that make it difficult or impossible for some people to undergo certain dental procedures. The purpose of this study was to analyze the sedation protocols used in 3 dental specialty programs at the Case Western Reserve University School of Dental Medicine, Cleveland, OH. METHODS: A retrospective analysis was performed using dental school records of patients receiving moderate sedation in the graduate endodontic, periodontic, and oral surgery programs from January 1, 2010, to December 31, 2012. Information was gathered and the data compiled regarding the reasons for sedation, age, sex, pertinent medical conditions, American Society of Anesthesiologists physical status classifications, routes of administration, drugs, dosages, failures, complications, and other information that was recorded. RESULTS: The reasons for the use of moderate sedation were anxiety (54%), local anesthesia failures (15%), fear of needles (15%), severe gag reflex (8%), and claustrophobia with the rubber dam (8%). The most common medical conditions were hypertension (17%), asthma (15%), and bipolar disorder (8%). Most patients were classified as American Society of Anesthesiologists class II. More women (63.1%) were treated than men (36.9%). The mean age was 45 years. Monitoring and drugs varied among the programs. The most common tooth treated in the endodontic program was the mandibular molar. CONCLUSIONS: There are differences in the moderate sedation protocols used in the endodontic, periodontic, and oral surgery programs regarding monitoring, drugs used, and record keeping.

The effect of docosahexaenoic acid (DHA) on expression of IL-1ß, IL-6, IL-8, and TNF-α in normal and lipopolysaccharide (LPS)-stimulated macrophages.

OBJECTIVE: Differentiated macrophages (MØ) are the resident tissue phagocytes and sentinel cells of the innate immune response. These cells are major constituents of periapical granulomas. Current studies indicate these activated cells as the source of bone-resorbing cytokines in the periapical granuloma. Periapical inflammation can be mediated by proinflammatory cytokines like interleukin 1ß (IL-1ß), tumor necrosis factor α (TNF-α), IL-6, and IL-8. Reducing the production of these cytokines may be beneficial for the treatment of periapical lesions. Oils rich in omega-3 fatty acids like docosahexaenoic acid (DHA) have been linked with anti-resorptive and bone-protective effects. The purpose of this investigation was to study the effect of DHA on the expression of these cytokines by normal and lipopolysaccharide (LPS)-treated MØ. We hypothesized that pretreatment of MØ with DHA decreases the expression of pro-inflammatory cytokines induced by LPS-treated MØ. METHOD AND MATERIALS: THP-1 monocytes were cultured and differentiated into MØ. DHA was added to MØ in a dose-dependent manner. MØ samples were added to the following groups: Group 1, ethanol alone as a solvent control; Group 2, 10 µg/ml of DHA (D1); Group 3, 20 µg/ml of DHA (D2); Group 4, 10 µg/ml of DHA + LPS (DL1); Group 5, 20 µg/ml of DHA + LPS (DL2); Group 6, LPS alone. Reverse transcriptase-PCR (RT-PCR) followed by ImageJ analysis was used to measure cytokine expression. RESULTS: The results show that IL-1ß and TNF-α levels for DL and DHA (basal) were significantly lower than the levels in LPS alone. IL-6 was increased in the DL groups. There was no significant change for IL-8. CONCLUSION: DHA at higher concentrations may selectively decrease proinflammatory cytokine production of IL-1ß and TNF-α. More studies are needed to verify the anti-inflammatory therapeutic action of agents like DHA omega-3 fatty acids.

A clinical report of the management of episodic idiopathic pruritus occurring during endodontic therapy.

INTRODUCTION: In endodontic practice, conditions may arise that are unexpected despite thorough preparation. The purpose of this case report was to describe how a condition of episodic idiopathic pruritus, which was undiscovered in the medical history taking, was managed without a loss of time. METHODS: A 29-year-old woman presented to the graduate endodontic clinic for conventional endodontic treatment of tooth #30 and intravenous moderate sedation for dental phobia. Before the administration of intraoral local anesthetics or intravenous medications, the patient was unable to keep still because of itching. When questioned, the patient reported that she suffers from this condition fairly regularly. The patient reported that the itching could be initiated by stress or for no apparent reason. Intraoral local anesthesia was administered, intravenous access was attained, and an analgesic and antihistamine were given. RESULTS: Two minutes after the administration of the antihistamine, the itching resolved, and the treatment was completed without further incident. CONCLUSIONS: This case provides an example of how an unexpected incident of episodic idiopathic pruritus was managed via the intravenous route without a loss of scheduled appointment time.

Introduction of implants into postdoctoral endodontic residency programs.

The purpose of this study was to survey the directors of postdoctoral endodontic programs in the United States to ascertain their attitudes and approaches regarding incorporation of implants into the endodontic curriculum. We hypothesized that program directors would agree that implant training should be incorporated into the endodontic curriculum. We also hypothesized that they would all prefer apical surgeries and retreatment over implants when plausible. A twenty-item online survey was emailed to all fifty-two postdoctoral endodontic program directors in the United States. A 100 percent response was received. The results showed that 78.6 percent agreed that implant training should be incorporated, 85.7 percent preferred the didactic approach, and 42.9 percent preferred clinical implant training. One hundred percent preferred apical surgeries and retreatment over implants when plausible, and 53.8 percent did not prefer implants over endodontic treatment for teeth with a questionable prognosis. This survey indicates that implant training has been incorporated into postdoctoral endodontic programs and that the Commission on Dental Accreditation standards are being met. The trend may be to become more hands-on in the future if program directors believe there is a need to provide training in actual placement of implants.

Genetic predisposition to persistent apical periodontitis.

INTRODUCTION: The proinflammatory cytokine interleukin (IL)-1 is a key regulator of host responses to microbial infection and a major modulator of extracellular matrix catabolism and bone resorption. Allele2 of IL-1ß is associated with a four-fold increase in IL-1ß production. The aim of this case-control study was to evaluate the gene polymorphism of IL-1ß in the pathogenesis of endodontic failure. We hypothesized that the gene polymorphism (allele2 of IL-1ß) would influence host response and enhance inflammatory reactions predisposing to persistent apical periodontitis (PAP). MATERIALS AND METHODS: Subjects with at least 1 year of follow-up after root canal therapy (RCT) were recalled. Inclusion and exclusion criteria were applied, and 34 subjects with signs/symptoms of PAP with otherwise acceptable RCT were included. Sixty-one controls showed healing with acceptable RCT. Genomic DNA from buccal mucosa was amplified by polymerase chain reaction followed by restriction fragment length polymorphism to distinguish the alleles of IL-1ß gene polymorphism. RESULTS: A significant difference in the distribution of the polymorphic genotype among cases (70.6%) and controls (24.6%) (P < .001, Pearson χ(2)) was shown. CONCLUSIONS: These findings suggest that specific genetic markers associated with increased IL-1ß production may contribute to increased susceptibility to PAP.

Evaluation of cutting efficiency of ultrasonic tips used in orthograde endodontic treatment.

The purpose of the present study was to evaluate the cutting efficiency of the three different ultrasonic tips for orthograde endodontic treatment: stainless steel, zirconium nitride-coated, and diamond-coated tips. An ultrasonic handpiece was mounted on a custom-made automated balance, and each tip repeatedly penetrated dental stone blocks to a depth of 3 mm for 10 times. The amount of time taken to penetrate 3 mm of stone was measured. The diamond-coated tips showed significantly greater cutting efficiency than either stainless steel tips or zirconium-nitride coated tips. The stainless steel tips showed initial better cutting efficiency, but over time , there is no significant difference between the cutting efficiency of the stainless steel tips and the zirconium nitride coated tips. The diamond coated tips were the only group that showed breakage in this study.