Objectives:The purpose of this study was to compare the quantity and quality of platelets in platelet-rich plasma (PRP) samples prepared using either the single- or the double-centrifugation protocol.Methods:Ten adult white New Zealand rabbits were used. Ten ml of blood were drawn from each animal via cardiac puncture. Each blood sample was divided into two equal parts for PRP preparation: 5 ml of blood were centrifuged according to a single-centrifugation protocol (Group I), and 5 ml were centrifuged according to a double-centrifugation protocol (Group II). Manual platelet counts were performed on the whole blood and PRP samples of each group. Smears were also done on all samples in order to see the morphology of the platelets. The data obtained in the manual platelet count were submitted to statistical analysis (repeated measures ANOVA, Tukey, P<.05).Results:The average whole blood platelet count was 446,389/μl. The PRP samples in Group II presented an average platelet amount significantly higher than that of Group I (1,986,875 ± 685,020/μl and 781,875 ± 217,693/μl, respectively). The PRP smears from Group II were the only one to present platelets with altered morphology (75% of the smears). A few lymphocytes with increased cytoplasm were observed in the PRP smears of both Groups I (25% of the smears) and II (62.5% of the smears).Conclusions:Within the limits of this study, it can be concluded that the double-centrifugation protocol resulted in higher platelet concentrations than did the single-centrifugation protocol. However, the double-centrifugation protocol caused alterations in platelet morphology and was more sensitive to small processing errors.

BG particles, used with or without a CS barrier, maintained the volume and contour of the area grafted in CSD. However, they did not lead to a significant difference in bone formation when compared with control at 12 weeks post-operative.

It can be concluded that the type of activator used to initiate PRP clot formation influences its biological effect on bone healing in CSD in rat calvaria.

Periodontal healing was similar using surgical debridement alone, AB graft, or AB graft with a CS barrier in the treatment of Class II furcation defects.

The objective of this study was to classify the morphology of bifid mandibular canals and to evaluate their relationship with the roots of third molars, using cone beam computed tomography (CBCT) scans. The CBCT scans of 75 patients were analyzed and the bifurcations were classified according to Langlais et al. (1985). The relationship of bifurcation and third molars was established according to the following classification: class A -uninvolved, class B -close relationship, class C -intimate relationship and class D -absence of third molars. Data were submitted to descriptive statistics, and the results indicated that the patients' mean age was 48.2 (± 13.2) years. Unilateral bifurcation (Type 1) was the most frequent type (72.6%), followed by unilateral Type 2 (19.3%). Class D was the most frequent (57.33%), followed by class C (21.33%), class B (13.33%) and class A (8%). It could be concluded that most cases presented unilateral bifid mandibular canals extending to the third molar or adjacent regions, and when present, the roots seemed to be a continuation of the bifid mandibular canal.