Joshua Moshonov

Effect of different endodontic treatment protocols on periodontal repair and root resorption of replanted dog teeth

This study examined, histologically, the healing of intentionally damaged root surfaces of replanted teeth with either uninfected or infected root canals treated with short- and long-term calcium hydroxide. Thirty beagle dog incisors were randomly divided into four groups. In group 1, uninfected obturated incisors were extracted, the roots were longitudinally grooved and the teeth were replanted within 2 min. In group 2 the root canals were artificially infected followed by extraction, longitudinal grooving, and replantation as described in group 1. Fourteen days after replantation, the root canals were fully instrumented and medicated with intracanal calcium hydroxide. One week later the root canals were permanently obturated with gutta-percha and sealer. The teeth in group 3 were treated as described in group 2 but after 1 wk the calcium hydroxide dressing was repacked for the duration of the study. In group 4 (positive control) the teeth were treated as described in groups 2 and 3 but no endodontic treatment was performed. After 8 wk, sacrifice and histological preparation were carried out. In group 1 complete cemental repair was seen in all teeth. In groups 2 and 3, complete and incomplete cemental repair was seen in seven and two teeth, respectively. An ankylotic area was present in one tooth in group 3. None of the teeth in group 4 showed cemental repair. It was concluded that short- and long-term calcium hydroxide treatment resulted in similar healing patterns when endodontic treatment is initiated 14 days after replantation of teeth.

Efficacy of removing glass ionomer cement, zinc oxide eugenol, and epoxy resin sealers from retreated root canals

Removal of gutta-percha and various sealers was assessed during retreatment of the root canal system. Sixty root canals were prepared and obturated with gutta-percha and Ketac-endo, Roths 801 cement, or AH26. After 14 days, the canals were retreated by hand or ultrasonic technique and the retreatment time was recorded. The roots were split and the amount of debris that remained on the canal walls in three separate levels was recorded by use of a dissecting microscope. The mean scores were compared by one-way and two-way ANOVA. The total score was significantly the highest for Ketac-endo (p less than 0.04), followed by AH26 and Roths 801 cement. The largest amount of debris was consistently found in the apical third, and generally it was comparable for both retreatment techniques. The ultrasonic technique was significantly faster than the hand technique for all sealers tested (p less than 0.0004, p less than 0.0003, p less than 0.02, respectively). Hand retreatment of Ketac-endo was the slowest, whereas ultrasonic retreatment of Roths 801 cement was the fastest. The results indicated that Ketac-endo endodontic sealer can be effectively removed from the root canal by ultrasonic instrumentation.

Antibacterial Properties of Four Endodontic Sealers

The purpose of this study was to evaluate the antimicrobial effects of root canal sealers. The direct contact test (DCT) was used to assess the antibacterial properties of AH plus, Apexit Plus, Epiphany SE, and RoekoSeal when in contact with Enterococcus faecalis. The materials were examined immediately after setting and 1, 2, 7, and 14 days after aging in phosphate-buffered-saline. Statistical analysis with two-way analysis of variance, one-way analysis of variance, and Tukey multiple comparison was applied to the data. Apexit Plus had a short-term antibacterial effect of 1 day on E. faecalis, whereas Epiphany SE enhanced bacterial growth for at least 7 days. AH plus and RoekoSeal were ineffective.

Efficacy of argon laser irradiation in removing intracanal debris

Endodontic instrumentation, irrigation, or intracanal medication are unable to totally remove intracanal debris. The purpose of this study was to evaluate the efficacy of argon laser irradiation in removing debris from the root canal system. After cleaning and shaping, 12 single rooted teeth were randomly divided into two groups of six teeth each. The first group, which served as the control, was not lased. In the second group, a 300 microns argon laser fiber optic was introduced into the root canal of each tooth, to its working length. Fifteen pulses of 100 msec each with an energy of 2 watts were delivered for 5 seconds at the apex. The lasing procedure was repeated at 1 mm intervals along the root canal, and the fiber tip was retrieved from the apex to the orifice. Computerized scanning electron microscopy analysis revealed that the amount of debris in the lased group was significantly lower than that in the control (p = 0.0001). On the basis of these results, it appeared that intracanal argon laser irradiation was an efficient mean of removing intracanal debris.

Dental Anxiety among Patients Undergoing Endodontic Treatment

The purpose of this study was to evaluate the dental anxiety expressed among patients undergoing endodontic treatment with respect to some social and dental parameters. The dental records of 98 patients, 42 men and 56 women who were referred for root canal treatment to an endodontist, were examined. Patients completed a Dental Anxiety Scale (DAS). Dental experience, time of last visit to the dentist, and symptoms of tooth were recorded. The mean DAS scores were higher than scores reported in other countries (9.4 +/- 3.3). Women demonstrated higher dental anxiety than men. Patients with higher education demonstrated lower dental anxiety. No difference was found between patients experienced in endodontic treatment and those who were not, patients who suffered previous pain in the treated tooth and patients who did not. Women in their mid-thirties to mid-forties and men in their twenties expressed the highest DAS scores.

Retreatment Efficacy 3 Months after Obturation Using Glass Ionomer Cement, Zinc Oxide-Eugenol, and Epoxy Resin Sealers

The efficacy of ultrasonic retreatment, 3 months after obturation, in conjunction with Ketac-Endo, Roths 801, and AH26 sealers was evaluated. Seventy-two root canals were prepared and obturated with gutta-percha and one of the sealers mentioned above. After 90 days, the canals were retreated by an ultrasonic technique and the retreatment time was recorded. The roots were split and the amount of debris that remained on the canal walls in three separate levels was scored. Compared by one-way and two-way analysis of variance, the mean scores of remaining debris at the different canal levels for the three sealer groups, as well as for each group, were not significantly different. The only significant difference was found in retreatment time for which Ketac-Endo was significantly slower to retreat than the other two sealers (p < 0.002). Thus, the results of this study showed that the amount of debris remaining on the root canal walls following retreatment 3 months after obturation is similar for Ketac-Endo, Roths 801, and AH26 sealers, but the retreatment time for Ketac-Endo is significantly longer.

Effect of chloroform, xylene, and halothane on enamel and dentin microhardness of human teeth☆☆☆★

OBJECTIVE The purpose of this study was to assess in vitro the effect of commonly used gutta-percha solvents on the microhardness of human enamel and dentin. STUDY DESIGN Crowns of human teeth were cut and treated with chloroform, xylene, and halothane. Treatment consisted of exposing the specimens for 5 or 15 minutes to the test solvents. Acid-treated and saline-treated specimens served as controls. After each treatment period, the specimens were rinsed, dried, and prepared for Vickers microhardness analysis. Vickers microhardness values for each specimen were recorded before and after treatment, and the differences were statistically compared. RESULTS A statistically significant decrease in enamel and dentin microhardness was found in most solvent-treated groups; the amount of the decrease was directly related to the exposure time. CONCLUSIONS Chloroform, xylene, and halothane may cause a significant softening effect on both enamel and dentin. This softening is already apparent after 5 minutes of treatment.

Effect of Er:YAG Laser-Activated Irrigation Solution on Enterococcus Faecalis Biofilm in an Ex-Vivo Root Canal Model

UNLABELLED Abstract Objective: The purpose of this study was to evaluate mineral content and surface morphology of root canals coated with Enterococcus faecalis biofilm after treatment with several endodontic irrigation solutions, with and without Er:YAG laser-activated irrigation (LAI). BACKGROUND DATA LAI has been introduced as a powerful method for root canal irrigation resulting in smear-layer removal from the root canal wall. METHODS Distal and palatal roots from 60 freshly extracted human molars were used in this study. The coronal of each tooth was removed. Roots were split longitudinally and placed in an ultrasonic bath to remove the smear layer, creating conditions for the formation of E. faecalis biofilm. After incubation, the two halves were reassembled in impression material to simulate clinical conditions. Specimens were divided into two main groups: roots rinsed with irrigation solutions and roots subjected to laser irradiation combined with irrigation solutions. Solutions tested were 2% chlorhexidine and 17% ethylenediaminetetraacetic acid (EDTA) and saline. RESULTS Surface morphology: 17% EDTA irrigant solution combined with Er:YAG laser showed the best results for removing bacteria from the root canal walls. Chemical analysis: all samples treated with combined laser irradiation and irrigation solution had low surface levels of Ca compared with samples treated with irrigation alone. The Ca/P ratio was highest in the laser-EDTA group. Overall, mineral changes caused by laser with irrigation solutions were minimal, and statistically nonsignificant. CONCLUSIONS In vitro irrigation solutions, combined with Er:YAG laser irradiation, were effective in removing E. faecalis biofilm from root canal walls. Irrigation solutions without laser irradiation were less effective, leaving a layer of biofilm on the dentin surface.

Endoscopic Approach to Dental Implantology

OBJECTIVE To describe an innovative miniature visualization surgical endoscope and endoscopic techniques applicable to dental implant procedures. MATERIALS AND METHODS A newly developed modular dental implant endoscope is introduced, and the first impressions from its use in different implant procedures are reported. RESULTS Details of the device that combines an endoscope, irrigation cannulas, and a surgical microinstrument channel are presented. The advantages of using it in dental implant procedures are described, and examples of how miniature visualization and surgical endoscopic techniques can be applied to increase the success of implantation are outlined. The new modular implant endoscope accurately identified all microanatomical and pathological structures, and simplified dental implant procedures. CONCLUSION Endoscopy should be considered not only for intraoperative observation and assessment of implant sites, but also should be applied for active assistance during implant placement procedures.

Cleaning of the Root Canal Using Nd:YAP Laser and Its Effect on the Mineral Content of the Dentin

OBJECTIVE The aim of this study was to compare the efficacy of root canal cleanliness with and without Nd:YAP laser and to assess the effect of the laser on the mineral content of the dentin. BACKGROUND DATA A high degree of cleanliness of the canal when using the Nd:YAG laser has been shown while the laser is in contact with the canal wall. A new Nd:YAP laser has been studied recently, which is considered to be superior to the Nd:YAG with regard to antibactericidal ability due to its 1.34 micro m wavelength, which is in the infra-red range. This wavelength is absorbed better in water than that of Nd:YAG. MATERIALS AND METHODS Fourteen extracted single rooted premplars were divided into two groups. In group 1, canals were cleaned, instrumented, and shaped with K files. In group 2, initial preparation was done using K files and completed with a Nd:YAP laser. Teeth were then split longitudinally and submitted to scanning electron microscopy. RESULTS The cleanliness of the laser-treated teeth was significantly greater than teeth treated with K files alone (p < 0.05). No difference in Ca and P content was detected when the use of K files was compared to the use of laser. CONCLUSION It appears that the Nd:YAP laser improves the cleanliness of the root canal. However, since the Nd:YAP laser serves as an addition to K files, its clinical value for replacing conventional root canal instrumentation remains to be determined.