A comparison of different bone graft materials in peri-implant guided bone regeneration

Abstract The aim of this study was to compare the effects of hydroxyapatite (HA), deproteinized bovine bone (DPB), human-derived allogenic bone (HALG), and calcium sulfate (CAP) graft biomaterials used with titanium barriers for bone augmentation to treat peri-implant defects in rat calvarium treated by guided bone regeneration (GBR). Thirty-two female Sprague-Dawley rats were divided into four groups: DPB, HALG, HA, and CAP. One titanium barrier was fixed to each rat's calvarium after the titanium implants had been fixed. In total, 32 titanium implants and barriers were used. Ninety days after the surgical procedure, all the barriers were removed. After decalcification of bone tissue, the titanium implants were removed gently, and new bone regeneration in the peri-implant area was analyzed histologically. Immunohistochemical staining of vascular endothelial growth factor (VEGF) was also performed. There were no statistically significant between-group differences in new bone regeneration or VEGF expression after 3 months. According to the results of the histological and immunohistochemical analyses, none of the grafts used in this study showed superiority with respect to new bone formation.

Systemic melatonin application increases bone formation in mandibular distraction osteogenesis

Abstract This study aimed to investigate the effects of different doses of systemic melatonin application on new bone formation during mandibular distraction osteogenesis (DO) in rats. Mandibular DO was performed on 30 adult female Sprague-Dawley rats, which were randomly divided into three groups: control group (CNT), melatonin dose 1 (MLT-D1), and melatonin dose 2 (MLT-D2). A five-day latent waiting period and a ten-day distraction phase followed the surgery. After the surgery, rats from the MLT-D1 and MLT-D2 groups received 25 and 50 mg/kg melatonin, respectively, at 7, 14, 21, 28, and 35 days. The animals were euthanised 28 days after distraction, i.e. at 43 days after surgery. Histological and histomorphometric analyses revealed that the distracted bone area was completely filled with new bone formation in all three groups. The MLT-D2 group exhibited the most new bone formation, followed by MLT-D1 and CNT. The melatonin groups had more osteoclasts than the CNT (p < 0.05). The number of osteoblasts was higher in the melatonin groups than in the CNT group, and the MLT-D2 had more osteoclasts than the MLT-D1 group (p < 0.05). Finally, the osteopontin (OPN) and vascular endothelial growth factor (VEGF) levels were higher in the melatonin groups than in the CNT group, and the MLT-D2 had higher OPN and VEGF levels than the MLT-D1 (p < 0.05). This study suggests that systemic melatonin application could increase new bone formation in DO.

Effects of sildenafil on dental pulp: immunohistochemical and ultrastructural evaluation / Efectos de sildenafil en la pulpa dental: evaluación inmunohistoquímica y ultraestructural

Sildenafil is a strong peripheral vasodilator and is used to treat cardiovascular and neurosurgery. The purpose of this study was to investigate the immunohistochemical and ultrastructural effects of sildenafil on dental pulp of rats. The study was performed with adult female Wistar-Albino rats. Control group (n= 7) were fed on standard laboratory diet until surgery. The study group (n= 7) were administered sildenafil orally with orogastric tube 10 mg·kg-1 once a day for 30 days. Each rat was anesthetized and incisor teeth were removed. This study examined the immunohistochemical and ultrastructural effects of sildenafil on the dental pulp in rats. The relaxation from the vessel, endothelial cell hyperplasia, moderate degeneration of collagen fibers were observed to cause degenerative changes in odontoblast with sildenafil. In the pulp tissue long-term use sildenafil is thought to cause degeneration and new vessel formation.

El sildenafil es un vasodilatador periférico importante y se utiliza para tratar enfermedades cardiovasculares y en neurocirugía. El propósito de este estudio fue investigar los efectos inmunohistoquímicos y ultraestructurales del sildenafil sobre la pulpa dental de ratas. El estudio se realizó con ratas Wistar albinas, hembras adultas. El grupo de control (n= 7) fue alimentado con una dieta estándar de laboratorio hasta que se realizó la cirugía. El grupo de estudio (n= 7) fue tratado con sildenafil por vía oral y sonda orogástrica 10 mg·kg-1 una vez al día durante 30 días. Cada rata fue anestesiada y se extrajeron los dientes incisivos. Se examinaron los efectos inmunohistoquímicos y ultraestructurales del sildenafil sobre la pulpa dentaria. Con la administración de sildenafil se observó la relajación de los vasos, la hiperplasia de las células endoteliales y una degeneración moderada de fibras colágenas causando cambios degenerativos en los odontoblastos. En el tejido pulpar, el uso de sildenafil a largo plazo puede causar la degeneración y neoformación de vasos.

Mandibular fractures: a comparative analysis between young and adult patients in the southeast region of Turkey

OBJECTIVE: The purpose of this study was to review and compare the differences between mandibular fractures in young and adult patients. MATERIAL AND METHODS: Patients treated at the Oral and Maxillofacial Department of Dicle University during a five-year period between 2000 and 2005 were retrospectively evaluated with respect to age groups, gender, etiology, localization and type of fractures, treatment methods and complications. RESULTS: 532 patients were included in the study, 370 (70 percent) males and 162 (30 percent) females, with a total of 744 mandibular fractures. The mean age of young patients was 10, with a male-female ratio of 2:1. The mean age of adult patients was 28, with a male-female ratio of 3:1. The most common causes of injury were falls (65 percent) in young patients and traffic accidents (38 percent) in adults. The most common fracture sites were the symphysis (35 percent) and condyle (36 percent) in young patients, and the symphysis in adults (36 percent). Mandibular fractures were generally treated by arch bar and maxillomandibular fixation in both young (67 percent) and adult (39 percent) patients, and 43 percent of the adult patients were treated by open reduction and internal fixation. CONCLUSION: There was a similar gender, monthly and type of treatment distribution in both young and adult patients in the southeast region of Turkey. However, there were differences regarding age, etiology and fracture site. These findings between young and adult patients are broadly similar to those from other studies. Analysis of small differences may be an important factor in assessing educational and socioeconomic environments.