Purpose: To compare the presenting symptoms and the outcomes of root canal therapy between HIV positive and HIV negative endodontic patients over a 6-12 month period. Methods: Fifty-nine HIV negative and 46 HIV positive patients presented for endodontic treatment. Signs and symptoms were noted and compared for both groups of patients, together with demographic data and CD4 counts for the HIV positive patients. Endodontic procedures were evaluated after an 18-month period. Endodontic treatment was assessed using clinical factors (palpation, percussion, sensitivity to hot and cold, swellings, excessive bleeding), and radiographic factors (periapical radiolucency, root resorption, periodontal ligament space). Results: There was no statistically significant difference in the preoperative presenting symptoms of endodontic infections/conditions between HIV positive and HIV negative patients. The prevalence of radiographic caries in the presenting teeth was only 24% in the HIV positive patients compared with 95% in the HIV negative patients. For the HIV positive patients, the treatment time required to resolution of the endodontic infection was nearly twice (113 minutes) that of the HIV negative patients (52 minutes). Amongst the HIV positive patients still experiencing symptoms at 18 months, pain was more severe in those patients with lower CD4 counts (significance at the 90% level of confidence). Conclusion: Within the limitations of this study the following conclusions emerge: 1. Although the success rate was lower over the period of this study in HIV positive patients, the rate is sufficiently high to warrant treatment. 2. Patients who are HIV positive may present with more severe symptoms and during treatment more bleeding may be expected. 3. In keeping with best practice for immuno-compromised patients, it would be advantageous to put HIV positive patients on antibiotic cover during treatment. 4. The process of anachoresis may explain the high incidence of endodontic infections in teeth with no history of trauma or caries in the HIV positive group.

No description available.

The objective of this study was to evaluate the biofilm removal efficacy of three root canal treatment systems: ProUltra® PiezoFlow™, traditional needle irrigation, and the GentleWave® system in an ex-vivo benchtop study. Twenty-four extracted maxillary and mandibular molars were selected. Teeth were all instrumented to a master apical file size #25 with 4% taper. Teeth were then randomly divided into four experimental groups and two control groups. The root canals were inoculated with a culture of Enterococcus faecalis and incubated for five weeks to form a biofilm. Each group was then treated with one of the different root canal treatment systems using 6% sodium hypochlorite (NaOCl) as per the respective manufacturer’s recommendation followed by a rinse with water. Following treatment, teeth were decoronated and roots were sectioned longitudinally. Three scanning electron microscope images were taken at the apical level per root half at 5000x magnification. Images were scored by four calibrated examiners blind to group membership using a four-point scoring system (<5% coverage, 5-33%, 34-66%, and >66%). Results were analyzed using mixed model ANOVA. All the experimental groups were significantly better than the positive control group in removing biofilm. Among the experimental groups, the GentleWave® 15/04 group was significantly better than the other groups. There was no significant difference between the GentleWave® and the ProUltra® PiezoFlow™. Traditional needle irrigation scored the worst in reducing E. faecalis biofilm. The GentleWave™ system was as effective at intracanal biofilm removal as the ProUltra® PiezoFlow™ and better than traditional needle irrigation using 6% NaOCl as an irrigant.

K3 ENDO, PRO TAPER, AND PRO FILE SYSTEMS: BREAKAGE AND DISTORTION IN SEVERELY CURVED ROOTS OF MOLARS.By Matthew T. Ankrum, D.D.S.A Thesis submitted in partial fulfillment of the requirements for the degree of Master of Science at Virginia Commonwealth University.Virginia Commonwealth University, 2003Major Director: Gary R. Hartwell, D.D.S., M.S.Chairman and Professor, Department of EndodonticsIt was the aim of this study to investigate the incidence of file breakage and distortion when the Pro Taper, K3 Endo and ProFile systems were used to instrument canals in the severely curved roots of extracted molars.Forty-five roots of extracted mandibular and maxillary molars with curvatures between 40 and 75 degrees were chosen for use in this study. The roots in Group One were instrumented with the Pro File (PF) system and served as the control group. Roots in Group Two were instrumented with the Pro Taper (PT) system and those in Group Three were instrumented with the K3 Endo (K3) system. The three systems were used according to the manufacturers' instructions.The proportion of files distorted was 15.3% for the PF group, 2.4% for the PT group, and 8.3% for the K3 group. There was a statistically significant difference between the PF and PT groups (p = .0079). The percentage of broken files was 1.7% for the PF group, 6.0% for the PT group and 2.1% for the K3 group. No statistically significant differences were found between these three groups (p = .4243). The results of this study showed that these three rotary tapered systems were not significantly different with regard to breakage. There were significantly more distorted files in the PF group when compared to the PT group, with regard to distortion there was no significant difference between the PT and K3 and the PF and K3 groups.

The purpose of this study was to determine the changes in prescribing habits of active members of American Association of Endodontics (AAE) with regards to antibiotics in comparison to the findings reported by Yingling et al. in 1999. The invitations to take the online survey were sent via email to 2593 active members. A response rate of 37.75% was obtained. It was determined to be adequate for analysis and for comparison to the results obtained by Yingling et al. Comparisons between the percentages shown in this survey and the previous survey were tested using a z-test. An ANOVA model was used to determine the relationships between predictive factors and the number of prescriptions written. The change in distribution of respondents was notable with an increase in younger clinicians (25% in 1999 to 36% at present). They were more likely to be in private practice and much less in part-time academic and private practice setting. The number of patients being seen per week and the number of prescriptions written per week also decreased in comparison (p<0.001). For all the considered factors, it was also noted that board certified endodontists were prescribing less antibiotics per week. A positive correlation was noted for number of years in practice (p=0.0006), type of practice (p<0.001) and number of prescriptions written per week. Changes in choice of antibiotics were also noted. There was a decrease in use of Penicillin (61.48% to 43%), an increase in the use of Amoxicillin (27.5% to 37.6%), and an increase in use clindamycin (45.3% to 64%) for patients with no medical allergies. As for patients with medical allergies, there was a steep incline in the use of clindamycin (56.03% to 90.3%) as first choice to an increase in azithromycin (7.4% to 38%) as a second choice. An improved trend was noted with a significant decrease in use of antibiotics in managing most of the endodontic scenarios given. Antibiotic use in cases of irreversible pulpitis significantly dropped from 16.76% to 12% (p<0.05); in necrotic pulps with acute apical periodontitis with no swelling, a significant decline from 53.9% to 28.3% (p<0.001); significant decreases were also noted for necrotic pulp with chronic apical periodontitis with no/mild symptoms, 18.8% to 16.1% (p=0.029), and necrotic pulp with acute apical periodontitis with swelling and mod/severe symptoms, 99.2% to 92.4% (p<0.001). An exception was noted for necrotic pulp with chronic apical periodontitis with a sinus tract where there was a significant increase in antibiotic use from 11.9% to 29.1% (p<0.001). Many clinicians (19%) were still giving antibiotics due to soliciting of patients and referring general dentists in fear of losing referrals. A disturbing find is that 50% of the respondents were using antibiotics to manage post treatment flare-ups and pain, while 13% were using antibiotics for inter-appointment pain. As for prophylactic antibiotics, most clinicians were aware of the new AHA/ADA guidelines and were abiding by them. Most of the clinicians responding to survey were choosing the appropriate antibiotics and regimen (i.e. dosage, loading dose, and duration). Although there is an improvement in trends, it has to be noted that there is still an indiscriminate and overuse of antibiotics at large. There needs to be greater improvement in the use of antibiotics in endodontics, and a group effort as a specialty is needed in halting this alarming problem of antibiotic resistance globally.

Endodontic or root canal treatment is one of the most important dental procedures employed in modern dentistry. Although there have been many results in surgical simulation in the past two decades, little work has been done on endodontics. The objective of this thesis is to explore critical issues for simulating root canal procedures effectively and efficiently, and to develop an interactive virtual environment featured with both visual and haptic feedback to facilitate endodontic training, which opens new roads to the research of root canal simulation and endodontic training. Beyond endodontics, the results of this work can be extended and applied to other kinds of medical simulation and biomechanical modeling, especially the simulations featured with interactions between soft tissue and solid tool objects. / This work covers both theories and methodologies related to the interactive endodontic simulation and validation, including dynamic modeling, visual and haptic display, model validation and statistical learning. We focus on the simulation of the most critical step in the entire endodontic procedure---shaping root canal with endodontic files. There are four major contributions of this thesis. First, we propose a dynamic model to simulate endodontic shaping operations, which is a smoothed particle based dynamic model derived for the pulpal tissue coupled with a finite element model for the endodontic files. This approach effectively characterizes the special properties and constraints associated with both the pulpal tissue and the endodontic files. Second, we implement the derived dynamic model and build up the virtual environment for endodontic simulation with both graphic and haptic interfaces. Third, we design a novel Robotic Endodontic Measurement System to acquire real haptic data of interactions between root canal and endodontic files during endodontic shaping, and propose an experimental validation method to evaluate the performance of derived dynamic model. Finally, we propose a support vector regression model to accurately characterize the input-output haptic mapping for endodontic shaping operation. The optimized parameters of this model can be learned from robotic endodontic measurements with RBF kernel. / Li Min. / "December 2005." / Adviser: Yun-Hui Liu. / Source: Dissertation Abstracts International, Volume: 67-11, Section: B, page: 6554. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (p. 108-116). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.

Thesis (M.S.)--University of Michigan, 2001. / Includes bibliographical references.

We investigated the antibacterial effect of low concentrations of double antibiotic paste (DAP) loaded into a methylcellulose system against bacterial biofilms obtained from mature and immature teeth with necrotic pulps. Standardized radicular dentin specimens were randomly divided into six experimental groups (n = 20). Group 1: 5mg/mL DAP treatment. Group 2: 1mg/mL DAP treatment. Group 3: Calcium hydroxide (Ca(OH)2) treatment. Group 4: Methylcellulose. Group 5: No treatment. Group 6: No bacteria or treatment. Clinical bacterial isolates were obtained from mature and immature teeth with necrotic pulps indicated for endodontic regeneration or routine endodontic treatment, respectively. Specimens in each group were inoculated with either bacterial isolates (n = 10) and incubated anaerobically for 3 weeks. Specimens were then treated for one week with the assigned group treatment. Treatments were rinsed with sterile saline and biofilms were detached and spiral plated using biofilm disruption assays. Wilcoxon Rank Sum tests followed by pair-wise comparisons were used for statistical analyses. Treatment of infected dentin with 1 mg/ml of DAP, 5 mg/mL of DAP, and Ca(OH)2 demonstrated significant and substantial antibiofilm effects in comparison to untreated control groups or groups treated with placebo paste. Furthermore, 1 mg/mL of DAP caused complete eradication of biofilm obtained from mature tooth with necrotic pulp. However, the same concentration was not able to completely eradicate biofilm obtained from the immature tooth with necrotic pulp. Low concentrations of DAP (1-5 mg/mL) loaded into a biocompatible methylcellulose system demonstrated significant antibacterial effects against biofilm obtained from both mature and immature teeth with necrotic pulps.

Indiana University-Purdue University Indianapolis (IUPUI) / Introduction: Regenerative endodontic procedures require adequate disinfection of immature teeth with necrotic pulps. Regeneration endodontic procedures have been shown to increase width and length of dentin after disinfection of the root canal system with various antibiotic pastes such as double antibiotic paste (DAP). DAP is composed of an equal ratio of metronidazole and ciprofloxacin. After the root canal system is disinfected with DAP, it is later flushed out with 17-percent EDTA. There is a need for a radiopaque component in the DAP to facilitate proper placement. Following disinfection with DAP, a residual antibacterial effect is formed in dentin. It is not known if this effect is modified by making DAP radiopaque. Objectives: The residual antibacterial effects of a radiopaque double antibiotic paste against a bacterial isolate obtained from an immature tooth with necrotic pulp on radicular dentin will be explored utilizing various strengths of DAP (1 mg/mL, 10 mg/mL, and 25 mg/mL) after 1 week and 4 weeks. Materials and Methods: Dentin samples of 4x4-mm will be prepared from previously extracted human posterior teeth. The samples will be assigned to seven treatment groups in a random fashion (G1 will be treated with 25-, G2-10, and G3-1 mg/mL of radiopaque DAP. G4 will be treated with the radiopaque filler without DAP. G5 will be treated with Ca(OH)2 and G6 sterile water with bacterial biofilm, and G7 will be sterile water). The groups will be treated for both 1 week 4 weeks. These samples will then be stored in a phosphate buffered saline (PBS) solution for 1 week and then inoculated with the cultured bacterial isolate from an immature tooth with necrotic pulp. The specimens will be incubated for three weeks to permit adequate formation of a biofilm. The biofilm will be detached, diluted and spirally plated onto blood agar plates and incubated for a total of 48 hours in 5-percent CO2 at 37°C. The number of CFUs/mL will be counted using an automated colony counter. A two way ANOVA and Fisher’s Protected Least Significant Differences test using 5-percent significance level will be used to evaluate the resulting data. Expected outcome: A residual antibacterial effect will be observed on radicular dentin samples when treated with radiopaque DAP. Conclusion: Using a radiopaque DAP that provides residual antibacterial effects, further awareness into regenerative endodontic procedures will be gained leading to alterations in treating such cases. / 2020-06-30

In December 2019, the coronavirus disease 2019 (COVID-19) was first identified as an acute infectious disease in Wuhan, China and subsequently led to an ongoing pandemic. At the onset of the pandemic, dental professionals were understood to face the greatest exposure risk to SARS-Cov-2 due to aerosolization of fluids from the oral cavity and respiratory airways . As a result, dental professionals, including academic institutions and their students and residents halted much of their operations to minimize exposure risks and potentially slow the spread of infection to peers and patients alike. Currently, there is little in the literature that describes the changes that academic institutions have implemented in the face of pandemics. This study will discuss the chronology, modifications, and possible resultant outcomes of COVID-19 related events in respect to Graduate Endodontic programs in the United States.