A Scanning Electron Microscope Evaluation of Smear Layer Removal and Antimicrobial Action of Mixture of Tetracycline, Acid and Detergent, Sodium Hypochlorite, Ethylenediaminetetraacetic Acid, and Chlorhexidine Gluconate: An In vitro Study.

OBJECTIVES: The main objective is to evaluate the efficiency in removal of smear layer of mixture of tetracycline, acid and detergent (MTAD), sodium hypochlorite (NaOCl), ethylenediaminetetraacetic acid (EDTA) and chlorhexidine gluconate by scanning electron microscope (SEM) evaluation and also to evaluate the antimicrobial action of the same irrigants against standard culture strains of Enterococcus faecalis. MATERIALS AND METHODS: This study included 60 extracted permanent teeth with single root canal. The sample was categorized into five groups with 12 teeth in each group. Root canals were enlarged till size 40 with K-files. One group was kept as control and irrigated only with saline. Other four groups used 5% NaOCl as irrigant during instrumentation and MTAD, 5% NaOCl, 17% EDTA, and 2% chlorhexidine gluconate as final rinse. Teeth were split and examined under SEM. To test the antibacterial action, the zone of inhibition method using agar plates was used. Obtained data were statistically analyzed by SPSS version 17 (SPSS Inc., Chicago, IL, USA). RESULTS: MTAD and 17% EDTA removed smear layer from all regions of the root canals. About 5% NaOCl and 2% chlorhexidine gluconate were ineffective in removing the smear layer. The mean zone of inhibition formed by the irrigants was in the following order; MTAD (40.5 mm), 2% chlorhexidine gluconate (29.375 mm), 17% EDTA (24.125 mm), 5% NaOCl (22.125 mm), and saline (zero). CONCLUSION: MTAD showed high smear layer removal efficacy, but no significant difference was found to that of 17% EDTA. As the dimensions of the zones of inhibition showed, MTAD has got highest antibacterial action against E. faecalis, followed by 2% chlorhexidine gluconate, 17% EDTA, and 5% NaOCl. However, the exact correlation of in vitro study results to clinical conditions is impossible due to the variables involved.

Evaluation and comparison of the microhardness of enamel after bleaching with fluoride free and fluoride containing carbamide peroxide bleaching agents and post bleaching anticay application: An in vitro study.

AIMS AND OBJECTIVES: The purpose of the study was to evaluate and compare the microhardness of enamel after the application of anticay on bleached enamel with fluoride containing and fluoride free bleaching agent. MATERIALS AND METHODS: Twenty freshly extracted teeth decoronated and divided mesiodistally into two halves were randomly divided into five groups with 10 samples in each group. The enamel surface was treated as follows: Group 1 - no treatment, Group 2 - fluoride free bleaching agent, Group 3 - fluoride containing bleaching agent, and Group 4 - fluoride free bleaching agent followed by anticay application. The samples were subjected to indentation to test the microhardness using Vicker's hardness analyzer. CONCLUSION: Enamel microhardness significantly increased in samples where anticay was used after the application of bleaching agent.

Pain Duration and Resolution following Surgery: An Inception Cohort Study.

OBJECTIVE: Preoperative determinants of pain duration following surgery are poorly understood. We identified preoperative predictors of prolonged pain after surgery in a mixed surgical cohort. METHODS: We conducted a prospective longitudinal study of patients undergoing mastectomy, lumpectomy, thoracotomy, total knee replacement, or total hip replacement. We measured preoperative psychological distress and substance use, and then measured pain and opioid use after surgery until patients reported the cessation of both opioid consumption and pain. The primary endpoint was time to opioid cessation, and those results have been previously reported. Here, we report preoperative determinants of time to pain resolution following surgery in Cox proportional hazards regression. RESULTS: Between January 2007 and April 2009, we enrolled 107 of 134 consecutively approached patients undergoing the aforementioned surgical procedures. In the final multivariate model, preoperative self-perceived risk of addiction predicted more prolonged pain. Unexpectedly, anxiety sensitivity predicted more rapid pain resolution after surgery. Each one-point increase (on a four point scale) of self-perceived risk of addiction was associated with a 38% (95% CI 3-61) reduction in the rate of pain resolution (P = 0.04). Furthermore, higher anxiety sensitivity was associated with an 89% (95% CI 23-190) increased rate of pain resolution (P = 0.004). CONCLUSIONS: Greater preoperative self-perceived risk of addiction, and lower anxiety sensitivity predicted a slower rate of pain resolution following surgery. Each of these factors was a better predictor of pain duration than preoperative depressive symptoms, post-traumatic stress disorder symptoms, past substance use, fear of pain, gender, age, preoperative pain, or preoperative opioid use.

Self-loathing aspects of depression reduce postoperative opioid cessation rate.

OBJECTIVE: We previously reported that increased preoperative Beck Depression Inventory II (BDI-II) scores were associated with a 47% (95% CI 24%-64%) reduction in the rate of opioid cessation following surgery. We aimed to identify the underlying factors of the BDI-II (affective/cognitive vs somatic) associated with a decreased rate of opioid cessation after surgery. METHODS: We conducted a secondary analysis of the data from a previously reported prospective, longitudinal, observational study of opioid use after five distinct surgical procedures (total hip replacement, total knee replacement, thoracotomy, mastectomy, and lumpectomy) in 107 patients. The primary endpoint was time to opioid cessation. After exploratory factor analysis of the BDI-II, mean summary scores were calculated for each identified factor. These scores were evaluated as predictors of time to opioid cessation using Cox proportional hazards regression. RESULTS: The exploratory factor analysis produced three factors (self-loathing symptoms, motivational symptoms, emotional symptoms). All three factors were significant predictors in univariate analysis. Of the three identified factors of the BDI-II, only preoperative self-loathing symptoms (past failure, guilty feelings, self-dislike, self-criticalness, suicidal thoughts, worthlessness) independently predicted a significant decrease in opioid cessation rate after surgery in the multivariate analysis (HR 0.86, 95% CI 0.75-0.99, P value 0.037). CONCLUSIONS: Our results identify a set of negative cognitions predicting prolonged time to postoperative opioid cessation. Somatic symptoms captured by the BDI-II were not primarily responsible for the association between preoperative BDI-II scores and postoperative prolonged opioid use.