Effects of cold atmospheric pressure plasma and disinfecting agents on Candida albicans in root canals of extracted human teeth.

Reinfection in endodontically treated teeth is linked to the complexity of the root canal system, which is problematic to reach with conventional disinfection methods. As plasma is expected to have the ability to sanitize narrow areas, the aim of this study was to analyze the effect of cold atmospheric pressure plasma (CAP) on Candida albicans in root canals of extracted human teeth. CAP was applied as mono treatment and in combination with standard endodontic disinfectants (sodium hypochlorite, chlorhexidine and octenidine). Disinfection efficiency was evaluated as reduction of the logarithm of colony forming units per milliliter (log10 CFU/mL) supported by scanning electron microscopy as imaging technique. Plasma alone showed the highest reduction of log10 CFU, suggesting the best disinfection properties of all tested agents.

Comparison of K hand files and ProFiles 0.06/0.04 in simulated curved root canals prepared by students.

OBJECTIVES: The objective of this study was to compare the step-down technique in simulated curved root canals using K hand files (VDW) and ProFiles 0.06/0.04 (Dentsply Maillefer). METHOD AND MATERIALS: A total of 72 canals were blindly prepared by instructed students: 1 block with K files and a second one with ProFiles 0.06/0.04 in connection with the EndoStepper (SET). Postoperative images of the canals were taken, and an independent dentist assessed preparations for amount and position of material removed during preparation. Efficacy of the instruments is described in terms of canal shape, instrument failure, canal blockages, and preparation time. RESULTS: ProFile instrumentation provided well-centered and tapered preparations while maintaining the apical foramen; in contrast, the use of K files resulted in frequent alterations of the root canal. In the apical portion, both techniques showed unprepared areas. The coronal diameter in hand-instrumented canals was more irregular and wider than in those mechanically prepared. There was no separation of a ProFile instrument. Hand instrumentation was faster than mechanical, but the difference was not statistically significant. CONCLUSION: Under the conditions of the study, the ProFile rotary system was simple and safe to use and created better preparations than hand instrumentation.

Conventional treatment of dens invaginatus in maxillary lateral incisor with sinus tract: one year follow-up.

Endodontic treatment of a maxillary lateral incisor with dens invaginatus in association with sinus tract and lateroradicular lesion is reported. Invaginated teeth present technical difficulties with respect to their management because of complicated canal morphology. This case was treated by conventional root canal treatment. At follow up examination after one year the tooth was asymptomatic and radiographically showed repair of the lesion.

The sealing ability of ProRoot MTA when placed as an apical barrier using three different techniques: an in-vitro apexification model.

OBJECTIVE: To assess the sealing ability of ProRoot MTA when placed as an apical barrier using three different techniques. METHOD AND MATERIALS: Sixty freshly extracted single-rooted human teeth were decoronated and standardized to a root length of 15 mm. The root segments were prepared with Gates Glidden burs to simulate a divergent open apex of immature teeth and randomly assigned into three experimental groups of 20 samples each. MTA (5 mm) was placed by pluggers (Group A), paper points (Group B), or ultrasonic tips (Group C). A cotton pellet moistened with saline was placed in the root canals till the material set, and the coronal portion was sealed with Cavit. After 24 hours, the Cavit and cotton pellet were removed and the canals dried and obturated with warm guttapercha (Obtura) and AH 26 sealer. Coronal portions of all samples were then sealed with Cavit. All root segments were double-coated with nail varnish except for the open apex and were exposed to methylene blue dye for 48 hours at room temperature. The samples were sectioned longitudinally (layer thickness 0.4 mm) and the extent of dye penetration was measured with a stereomicroscope (magnification 20×). RESULTS: The mean depth (± standard deviation) of dye leakage for Group A was 1.34 ± 0.5 mm, Group B 1.25 ± 0.4 mm, and Group C 1.14 ± 0.4 mm. There were no significant differences among the three experimental groups (.178 < P < .552). CONCLUSION: ProRoot MTA has a similar sealing ability when placed as an apical barrier with pluggers, paper points, or ultrasonic tips.

One-year evaluation of an Ormocer restorative-a multipractice clinical trial.

The purpose of this ongoing prospective long-term study was to evaluate the clinical performance of Ormocer restorative material in combination with a self-conditioning adhesive. Five operators at five clinics placed 356 restorations (48 class I, 150 class II, 63 class III, 32 class IV, and 63 class V) in 117 patients aged 17 to 65 years. All fillings were placed with cotton roll isolation and clear matrix bands for class III and IV restorations, and metal matrix bands and an incremental placement technique were used for class II restorations. In follow-up examinations after 6 and 12 months, modified Ryge criteria were recorded on all restorations. With 33 randomly selected class I and II restorations, measurements of occlusal wear (via 3D laser scanner) and qualitative and quantitative marginal analysis (via scanning electron microscope) were performed using a replica technique. After placing the fillings, patients reported postoperative hypersensitivity corresponding to B scores in 19 cases and to C scores in four cases. At 12-month recall, 328 restorations were available for evaluation. Losses in the five cavity classes (I, II, III, IV, V) numbered 0, 2, 0, 1, and 6, respectively. The percentages of retained restorations for clinical parameters in four categories (Alpha, Beta, Charlie, Delta) were: 94.7, 5, 0.3, and 0 (marginal integrity), 81.2, 18.8, 0, and 0 (marginal discoloration), 75.2, 24.8, 0, and 0 (anatomic form), and 95, 4.7, 0.3, and 0 (fracture), respectively. Marginal analysis showed 48.7% "continuous margin" initially and 17.7% at 12 months (difference statistically significant, P=0.05). The occlusal wear at 12 months was 10.0 microm (SD 11.6) for premolars and 22.0 microm (SD 24.1) for molars. Over the 12-month observation period, the Ormocer restorative was clinically effective in combination with a self-conditioning adhesive, and concern persists related to the marginal quality and retention of class V restorations.