Evaluation of postoperative pain and healing following regenerative endodontics using platelet-rich plasma versus conventional endodontic treatment in necrotic mature mandibular molars with chronic periapical periodontitis. A randomized clinical trial.

AIM: To evaluate the post-operative pain and the healing of necrotic mature permanent mandibular molar teeth with peri-apical periodontitis after conventional endodontic treatment versus after platelet-rich plasma (PRP) revascularization. METHODOLOGY: The protocol of this randomized clinical trial was registered at www. CLINICALTRIALS: gov with identification number NCT03350841. Twenty-eight patients were included in the study after confirming the diagnosis clinically and radiographically. In the first visit, mandibular molar teeth of both groups were mechanically prepared. Double antibiotic paste was prepared and injected then the cavity that was sealed with glass ionomer. At the second visit, the patients were randomized either to control group where standard endodontic treatment was completed by lateral condensation technique or assigned to intervention group where PRP revascularization technique. The degree of spontaneous pain was assessed using numerical rating scale (NRS) pre-operatively, then post-operatively after 6, 12 h and daily for 5 days. Patients were given a placebo to be administrated in case of pain. An analgesic (ibuprofen 400mg) was prescribed in case of persistent pain. Clinical and radiographic healing was assessed after 6 and 12 months. All demographic, baseline and outcome data were collected and statistically analysed. RESULTS: Regarding the post revascularization/obturation pain, there was no statistically significant difference between severity of pain in the two groups at all time intervals except after 12 h, revascularization group showed statistically significantly higher prevalence of no pain than endodontic treatment group. Regarding the healing; the periapical lesions decrease in size significantly from the pre-operative lesion size in both groups without significant difference between the both groups. CONCLUSION: Within the limitation of this study, PRP revascularization could be an alternative treatment to root canal treatment but further randomized clinical trials with standardized techniques and long follow up periods are recommended for more reliable results.

Geometric analysis of root canals prepared by four rotary NiTi shaping systems.

INTRODUCTION: A great number of nickel-titanium (NiTi) rotary systems with noncutting tips, different cross-sections, superior resistance to torsional fracture, varying tapers, and manufacturing method have been introduced to the market. The purpose of this study was to evaluate and compare the effect of 4 rotary NiTi preparation systems, Revo-S (RS; Micro-Mega, Besancon Cedex, France), Twisted file (TF; SybronEndo, Amersfoort, The Netherlands), ProFile GT Series X (GTX; Dentsply, Tulsa Dental Specialties, Tulsa, OK), and ProTaper (PT; Dentsply Maillefer, Ballaigues, Switzerland), on volumetric changes and transportation of curved root canals. METHODS: Forty mesiobuccal canals of mandibular molars with an angle of curvature ranging from 25° to 40° were divided according to the instrument used in canal preparation into 4 groups of 10 samples each: group RS, group TF, group GTX, and group PT. Canals were scanned using an i-CAT CBCT scanner (Imaging Science International, Hatfield, PA) before and after preparation to evaluate the volumetric changes. Root canal transportation and centering ratio were evaluated at 1.3, 2.6, 5.2, and 7.8 mm from the apex. The significance level was set at P ≤ .05. RESULTS: The PT system removed a significantly higher amount of dentin than the other systems (P = .025). At the 1.3-mm level, there was no significant difference in canal transportation and centering ratio among the groups. However, at the other levels, TF maintained the original canal curvature recording significantly the least degree of canal transportation as well as the highest mean centering ratio. CONCLUSIONS: The TF system showed superior shaping ability in curved canals. Revo-S and GTX were better than ProTaper regarding both canal transportation and centering ability.