Biomedical subjects

James K Bahcall

Publications and source records attributed to James K Bahcall.

11 recordsLinked to original sources

PubMed2006

An in vitro comparison of the intraradicular dentin bond strength of Resilon and gutta-percha.

The purpose of this study was to compare the micropush-out bond strength of Resilon to that of gutta-percha. Extracted human anterior teeth were used for evaluation. The crowns were removed and the root canals were instrumented with Gates Glidden drills and 0.06 Profile rotary files. Instrumentation was performed with 5.25% sodium hypochlorite irrigation and a final rinse of 17% EDTA. The teeth were randomly divided into two groups. Gutta-percha group: obturation with gutta-percha and Kerr Pulp Canal Sealer EWT. Resilon group: obturation with Resilon points, Epiphany Primer, and Root Canal Sealant. The teeth were cut perpendicular to their long axis to obtain a series of 1.0 mm thick disks (n = 15 per group). Micropush-out bond strengths to root canal dentin were measured. The results show that the mean bond strength to root canal dentin was significantly higher (p < 0.05) in the Resilon/Epiphany group as compared to the gutta-percha/Kerr Pulp Canal Sealer EWT group.

Adhesiveness↗

PubMed2006

A comparison of thermal properties between gutta-percha and a synthetic polymer based root canal filling material (Resilon).

A new polymer-based obturating material, Resilon, has been developed but there have been no studies identifying its thermal properties. The purpose of this study was to compare the melting point, specific heat, enthalpy change with melting and heat transfer between gutta-percha (GP) and Resilon (R). The first three tests were determined using a differential scanning calorimeter and the heat transfer test was determined using a split-tooth model. Results show no significant difference (t test, p > 0.05) between gutta-percha and Resilon for the melting point temperature (GP: 60.01 degrees C; R: 60.57 degrees C). There was a significant difference (t test, p < 0.05) in specific heat capacity (GP: 0.94 J/g degrees C, R: 1.15 J/g degrees C) and endothermic enthalpy change (GP: 10.88 J/g, R: 25.20 J/g) between the two materials. The heat transfer test showed a significant difference (Mann-Whitney, p < 0.05) in temperature increase between gutta-percha and Resilon within 3 mm of the heat source.

Calorimetry↗

PubMed2006

In vitro evaluation of the antimicrobial effects of a root canal sealer-antibiotic combination against Enterococcus faecalis.

The purpose of this in vitro study was to evaluate the antimicrobial effects of five antibiotics when added to Kerr Pulp Canal Sealer EWT against Enterococcus faecalis. Five antibiotics: amoxicillin, penicillin, clindamycin, metronidazole, and doxycycline, were added separately to Kerr sealer. Thirty brain heart infusion agar plates were inoculated with E. faecalis and sterile paper discs containing a sealer-antibiotic combination were randomly assigned to the inoculated plates. Kerr sealer on a sterile paper disc and a blank sterile paper disc served as the controls. Fifteen plates were incubated aerobically and the remaining 15 plates were incubated anaerobically at 37 degrees C. The zones of inhibition were measured at 48 hours. No significant differences (p > 0.05) were found between aerobic and anaerobic groups. The groups were combined and data analysis using a one-way ANOVA and Tukey's post hoc test was performed. Results revealed that sealer-antibiotic combinations containing amoxicillin, penicillin, clindamycin, and doxycycline had a significant difference (p < 0.001) in the mean zones of inhibition when compared to Kerr EWT sealer alone. No significant differences (p > 0.05) were found between the metronidazole-sealer combinations and Kerr EWT sealer alone.

Aerobiosis↗

PubMed2005

An in vitro comparison of the rake angles between K3 and ProFile endodontic file systems.

The purpose of this study was to compare rake angles of the ProFile and K3 file systems. Twenty-five 40/0.06 taper files were obtained for each system. Five files from the same manufacturer were placed perpendicularly into a vial of Epoxicure Resin and left to set for 24 h. The set-ups were removed from the vials and each were sectioned 5 mm from the tip of the files and polished. A photomicrograph was taken of each file with 100x magnification. Five sets of ProFile and five sets of K3 files were processed in this manner. Images were captured digitally, and rake angles of each file were measured. Multivariate ANOVA found a significant difference (p < 0.001) among the three negative rake angles of the ProFile system compared with the K3 system.

Dental Instruments↗

PubMed2005

Low carb endodontics.

The field of endodontics has seen great technological advances and changes in thought processes over the last decade. Unfortunately, with these advances and changes has come an overload of information (too many carbs!). This article will help to reduce your intake of carbohydrate information and provide you with what you need to know about conventional endodontic treatment.

Dental Pulp Diseases↗

PubMed2005

The causes, prevention, and clinical management of broken endodontic rotary files.

Complications can occur during many dental procedures. The prepared clinician responds by either correcting the problem during treatment, or, ideally, preventing the problem from occurring in the first place. In endodontic treatment separated rotary Ni-Ti files are a common procedural problem. Through understanding that the main causes of file breakage are cyclic fatigue and torsional stress, a dentist can best prevent this occurrence by using hand files before rotary files, creating a straight-line (glide path) access into a canal, and preflaring the coronal portion before using rotary files in the apical third of the canal. In addition, using an up and down motion with the electric slow-speed handpiece (not allowing the file to bind within the canal) will significantly reduce the incidence of file breakage. If a file does break, successful removal primarily depends on the location of the file in the canal rather than the specific technique employed for removal. A case does not necessarily fail if the separated file cannot be removed. The prognosis when file separation occurs can still be favorable, especially if care was taken to reduce the critical concentration of canal debris with hand instrumentation and chemical irrigation prior to rotary file insertion. In addition, the introduction of a new CS file design will help the dentist increase the chance of removing the file in the event of breakage.

Dental Alloys↗

PubMed2004