Ronaldo Célio Mariano

Bone healing in critical-size defects treated with platelet-rich plasma: a histologic and histometric study in rat calvaria

BACKGROUND AND OBJECTIVE The purpose of this study was to analyze histologically the influence of autologous platelet-rich plasma on bone healing in surgically created critical-size defects in rat calvaria. MATERIAL AND METHODS Thirty-two rats were divided into two groups: the control group (group C) and the platelet-rich plasma group. An 8-mm-diameter critical-size defect was created in the calvarium of each animal. In group C the defect was filled by a blood clot only. In the platelet-rich plasma group, 0.35 mL of platelet-rich plasma was placed in the defect and covered by 0.35 mL of platelet-poor plasma. Both groups were divided into subgroups (n = 8) and killed at either 4 or 12 wk postoperatively. Histometric (using image-analysis software) and histologic analyses were performed. The amount of new bone formed was calculated as a percentage of the total area of the original defect. Percentage data were transformed into arccosine for statistical analysis (analysis of variance, Tukey, p < 0.05). RESULTS No defect completely regenerated with bone. The platelet-rich plasma group had a statistically greater amount of bone formation than group C at both 4 wk (17.68% vs. 7.20%, respectively) and 12 wk (24.69% vs. 11.65%, respectively) postoperatively. CONCLUSION Within the limits of this study, it can be concluded that platelet-rich plasma placed in the defects and covered by platelet-poor plasma significantly enhanced bone healing in critical-size defects in rat calvaria.

Bone healing in critical-size defects treated with platelet-rich plasma: a histologic and histometric study in the calvaria of diabetic rat.

OBJECTIVE The objective of this study was to histologically analyze the influence of the platelet-rich plasma (PRP) on bone healing in surgically created critical-size defects (CSD) in the calvaria of diabetic rats. STUDY DESIGN A total of 20 diabetic rats were divided into 2 groups: C (control) and PRP. A 5-mm diameter CSD was created in the calvarium of each animal. In Group C, the defect was filled by blood clot only. In Group PRP, 0.35 mL of PRP was placed in the defects. All animals were humanely killed 30 days postoperatively. Histometric and histologic analyses were performed. Data were statistically analyzed (t test, P < .05). RESULTS No defect completely regenerated with bone. Group PRP had a statistically greater amount of bone formation than Group C (37.22% +/- 6.00% and 21.68% +/- 11.35%, respectively). CONCLUSION PRP placed in the defects significantly enhanced bone healing in CSD in the calvaria of diabetic rats both qualitatively and quantitatively.

Anterior Pericranial Flap for Frontal Sinus Duct Obliteration: Is It a Valuable Resource?

Inappropriate treatments of frontal sinus fractures may lead to serious complications, such as mucopyocele, meningitis, and brain abscess. Assessment of nasofrontal duct injury is crucial, and nasofrontal duct injury requires sinus obliteration, which is often accomplished by autogenous grafts such as fat, muscle, or bone. These avascular grafts have an increased risk of resorption and infection and donor site morbidity. For these reasons, pericranial flap, which is vascular, should be used for frontal sinus obliteration. The pericranial flap presented with less morbidity procedure and has decreased infection rates, which justifies its use in frontal sinus obliteration. This study aimed to report a case of a comminuted frontal sinus fracture with a brief literature review, regarding the use of pericranial flap. The authors report a case of a 23-year-old male subject with a severely comminuted fracture of the anterior and posterior walls of the frontal sinus. The patient was successfully treated by cranialization with frontal sinus duct obliteration, using anterior pericranial flap. The patient was followed up for 16 months with no postoperative complication, such as infection. Pericranial flap is a good resource for frontal sinus duct obliteration because it is a durable and well-vascularized flap, which determines low rates of postoperative complications.

Effect of topical application of chlorhexidine and metronidazole on the tissue repair of palatal wounds of rats: a clinical and histomorphometric study

OBJECTIVE This study investigated the effect of topical application of 2% chlorhexidine (GCl) and metronidazole (Gme) pastes for the repair of palatal wounds in rats. STUDY DESIGN A 4-mm diameter wound was created on the palates of 27 rats separated randomly into 3 groups of 9 animals each, according to the treatment received: GNa (Control: natrosol), GCl, and GMe. The animals were euthanized after 3, 6, and 10 days, and wound closure was clinically and histomorphometrically assessed. RESULTS Clinical evaluation showed a statistically significant difference in tissue repair with GCl and GMe compared with GNa. In histomorphometric analysis, the highest values in the areas of the epithelium and keratin were observed for GCl and GMe; however, compared with Gna, no statistically significant differences were observed. CONCLUSIONS GCl and GMe pastes showed promising results with regard to tissue repair from a clinical point of view. Histologically, premature closure of wounds was noted in most specimens on day 6. Although no statistically significant differences were observed among the experimental groups with regard to histometry of the epithelium and keratin, the highest means were observed for GCl.

Effect of Doxycycline in Gel Form on Bone Regeneration: Histomorphometric and Tomographic Study in Rat Calvaria

BACKGROUND This study aims to investigate the effects of the local application of doxycycline in the form of natrosol-based gel on bone regeneration by examining critical defects in rat calvaria. METHODS Twenty-four rats were randomly divided into three groups with eight animals each, according to the treatment received: BC (untreated, filled with blood clot), NAT (natrosol gel alone), and DOX (10% doxycycline gel). Four animals from each group were euthanized at 4 and 8 weeks postoperatively. In tomographic analysis, mean density in the region of the defect was calculated as a percentage relative to the native bone density. In histomorphometric analysis, the newly formed bone area was calculated as a percentage of the total area. The values obtained underwent analysis of variance and Tukey testing (P <0.05). RESULTS The mean percentage of tomographic density in the region of the defect at the end of 8 weeks was higher for DOX (44.37%), and statistical differences in this period were observed between DOX and NAT (33.10%) and DOX and BC (32.43%). Regarding new bone formation, at the end of 8 weeks, DOX (61.11%) also had the highest mean bone formation, and statistical differences were observed between DOX and NAT (34.61%) and DOX and BC (23.11%). CONCLUSION It was observed that 10% doxycycline gel had a good effect on bone regeneration regarding the filling of critical defects in rat calvaria.

Open Reduction in Pediatric Condylar Fracture.

Facial fractures in children are rare. Lack of pneumatization, fat pockets, mixed dentition, contribute to the elasticity and bone stability. When mandibular fractures occur in children, most often involve the condyle by indirect trauma. Such fractures are the center of discussion on the form of treatment if this should be performed conservatively, or held the reduction and fixation of the fracture with surgical exposure of the fragments. In condylar fractures in children, in most patients, the proposed treatment is closed reduction. Treatment with open reduction and fixation has its specific indications. In this case, the authors report a patient cycling accident victim, with cut-contusion injury in ment with limited mouth opening and left condylar fracture with medial rotation. The treatment was the reduction and fixation of fragments by open process.

Papillary mucinous cystadenocarcinoma: rare malignant tumor in minor salivary gland

Clinical case description of a papillary mucinous cystadenocarcinoma, extremely rare malignant tumor in the salivary gland and difficult to diagnose, in geriatric patient. Patient with 86 years old was referred for treatment with nodular lesion on the inner side of left lower lip extending to the bucal mucosa, without any clinical appearances of malignancy. The lesion was asymptomatic, had flabby consistency and slow growth. Despite the favorable clinical features, after surgical removal, was diagnosed as papillary mucinous papillary mucinous cystadenocarcinoma. Nonetheless, the cellular atypia found was considered to be mild and immunohistochemical evaluation the reaction to Ki-67 was low, indicating a low rate of proliferation of the tumor. Medical evaluation confirmed the absence of systemic disorders or distant metastases. Although it is a malignant lesion, due to low degree of proliferation of lesion and the careful follow-up carried out, there was a favorable evolution after conservative treatment in a follow-up period of 11 years and six months.