The purpose of this study was to evaluate the effect of cortical bone perforation on angiogenesis and osteogenesis of the augmented ridge in guided bone regeneration. Eighteen patients who had osseous defects in the mandible were selected. In the test group ( n = 9), alveolar cortical bone in the area of regeneration was perforated. No decortication was performed in the control group ( n = 9). Subsequently, defects were augmented by guided bone regeneration using resorbable membrane and bovine bone. After a healing period of 7 months, trephine cores were harvested for histological and histomorphometric analysis of the grafted areas. Histomorphometry demonstrated that the amount of newly formed bone in the test group (27.8%) was greater than that in the control group (25.3%), but the difference was not statistically significant ( P = 0.13). However, the mean number of microvessels in the test group was significantly higher than that in the control group ( P = 0.01). This study found that cortical bone perforation favourably affects the amount of new bone formation in the grafted sites after 7 months of healing. Cortical bone perforation significantly increase number of new vessels (angiogenesis) of the regenerated bone. Further randomized clinical trials are required to confirm these results.
A sufficient amount of bone surrounding implants is essential to obtain a satisfactory treatment outcome in the long term. A deficiency of the alveolar ridge resulting from a trauma, pathology, or congenital defect, may impede implant placement. The principles of guided bone regeneration (GBR) have been used for many years to augment the bone height and/or width and provide clinicians with an adequate amount of bone for implant placement. Various clinical studies have shown bone regeneration within or beyond the confines of the original skeletal boundary by creating space for new bone formation and excluding soft tissue from invasion into the space.
The intramarrow penetration of cortical bone may affect the quality of regenerated bone by facilitating the migration of osteoprogenitor cells from the bone marrow into the isolated space created. Previous studies have used cortical bone decortication in different clinical conditions, such as periodontal osseous defects and alveolar ridge augmentation. However, perforation of the cortical bone prior to GBR is a controversial subject. Lee et al. showed that intramarrow perforation may improve the amount of newly formed bone and accelerate angiogenesis. In contrast, there are some studies that have shown no beneficial effect for perforation of the cortical bone prior to GBR.
The question of whether such perforations would have any effect on the quality of regenerated bone histologically in humans has not been addressed. This study evaluated the effect of intramarrow penetration on regenerated bone histologically in humans. The purpose of this study was to evaluate the effect of cortical bone decortication on the angiogenesis and osteogenesis of the augmented ridge in GBR.
Materials and methods
Eighteen patients (eight men and 10 women) who required dental implants in areas with mandibular osseous defects were selected. The patients had a median age of 52 years (age range 25–72 years) and were in good general health. All of the patients presented a partially edentulous mandible with either an extended or single tooth gap. Subjects were assigned to one of two groups: test patients ( n = 9) received perforation of the recipient bed; control patients ( n = 9) had no perforation of the recipient bed prior to GBR.
The inclusion criterion was the presence of an atrophic mandibular ridge with a buccolingual width of between 2 mm and 5 mm, as measured on serial sections of an axial computed tomography scan. Patients with diabetes, osteoporosis, or other metabolic disorders, smokers, pregnant patients, and patients who had any systemic or local factors that would inhibit a normal wound healing process were excluded. All of the patients volunteered to participate in the study and informed consent was obtained from each of them. The patients were informed that a biopsy specimen would be taken from the grafted site at the time of implant placement with no untoward effect on implant osseointegration. All procedures and materials were approved by the local ethics committee and the institutional board of research. The principles of the Declaration of Helsinki were followed in this study.