Limited evidence suggests guided bone regeneration with or without autogenous bone grafts are equivalently effective in horizontal bone gain

Summary Subjects Forty-two patients, requiring implant supported restorations, were recruited between May 2012 and September 2015 from the Periodontal Postgraduate Clinic at the Faculty of Dentistry, Cientifica del Sur University (CSU), Lima (Peru) fulfilling the following inclusion criteria; all were over age 18 years with horizontal mandibular or maxillary bone defects less than 4 mm at least on one side of the arch. Good oral hygiene and no previous history of augmentation at the selected implant sites were a must for including the patients. On the other hand, immune-compromised, pregnant, lactating patients or those with poor oral hygiene, untreated periodontitis, uncontrolled systemic diseases, history of irradiation in head and neck regions, history of receiving intravenous amino-bisphosphonates, parafunctional habits, drug or alcohol abusers, psychiatric disorders, heavy smokers, acute or chronic infection at the extraction site, or recent extraction sites with less than 3 months of healing were all excluded. Treatment Patients were randomly assigned either to the intervention (ABG group; 22 patients with 31 implants) or control group (GBR; 20 patients with 34 implants). In ABG the bone was harvested from the chin or the ramus, depending on the required amount of bone. Two to 3 implants, 3.6 mm in diameter and 12 mm in length, were then placed at each of the augmented sites 6 months later. They were kept submerged for another 4 to 6 months, after which they were restored with single, cement-retained crowns. Main outcome Cone-beam computed tomography (CBCT) scans at baseline and at 6, and 18 to 21 months of follow up were taken to evaluate the primary outcome, which was horizontal dimensional bone changes measured at 3 lines that were 5, 7, and 11 mm from the crest and that ran perpendicular to a bisector following residual bone inclination and dividing the image into a buccal and a palatal section. Secondary outcomes including implant failure and postoperative complications such as infection, hematoma, swelling, graft exposure, need for regrafting at the recipient sites, and sensory disturbance in both donor and recipient sites were also reported as binary outcomes. Outcome assessment was done by one blinded trained examiner. Main results A total of 3 patients did not complete all study visits due to loss of follow-up (2 in the GBR group and 1 in the ABG group). Mean increases in horizontal bone width (HBW) amounted to 5.6 ± 1.35 mm in GBR sites and 5.1 ± 0.87 mm in ABG sites at 6 months. There was no statistically significant difference in the increase of HBW obtained by the GBR group compared to that obtained by the ABG group at 6 months (P = .26). After 18 months, the mean increase in HBW was 5.6 ± 1.75 mm in GBR sites and 4.8 ± 0.79 mm in ABG sites. There was no statistically significant difference in the increase of HBW obtained by the GBR group compared to that obtained by the ABG group at 18 months (P = .26). Additionally, no implant failure at 12 months post-loading or need for regrafting in both groups was observed. Among the surgical complications that were assessed, hematomas and sensory disturbance were statistically more significant in ABG than GBR, favoring GBR. Conclusion Within the limitations of the study, GBR with or without autogenous block graft may be an effective approach in augmenting horizontally deficient mandibular or maxillary ridges, before the placement of dental implants. However, more complications may be seen with the use of an autogenous block graft related to the donor sites.