Assessment Of Bone Grafts Research Articles

Assessment of Bone Grafts: Authors’ Reply

We thank Dr Tan for his comments regarding our study. Statistics are used to test the validity of aims and hypotheses of a scientific study. Therefore, we used statistics to assess factors affecting the survival of bone grafts and these gave us a number of interesting and unexpected results.1 We agree the significance of diabetes was a surprise with the numbers involved, however it is consistent as a risk factor for bone graft failure, both in the clinical and scientific setting.2 The p value for this was 0.006 which is very significant. Diabetes is, however, not a contraindication for implant placement although significant complications related to risk of infection, can occur with placement of implants in diabetics with poor glycaemic control.3, 4 The other interesting finding the statistics revealed from our present study was that smoking was not a significant risk factor for graft failure. This was unexpected and counter-intuitive, particularly in relation to the vascularity issues required for revascularization related to smoking5 and the number of failures found in the smoking group. Some of these peculiarities with the statistical findings may be related to the modest numbers used in the study. We do, though, plan to revisit this topic when numbers are increased. This study was in effect, a preliminary audit of our results to date within the setting of an oral and maxillofacial surgical training programme. With statistics, you win some and you lose some, but they are there to serve a purpose. Sometimes you get some unexpected results, but these aren’t lies, they are just unexpected. If these results are relevant to the aims of the study, then they should be included.

Assessment of bone grafts placed within an oral and maxillofacial training programme for implant rehabilitation

This study aimed to review the survival of bone grafting procedures, performed by surgical trainees and assess factors affecting survival of these bone grafts as an adjunct to implant rehabilitation. Data were collected from patients between 2003 and 2009 receiving bone grafting. Graft failure was defined as any complete or partial graft loss, graft which had to be removed or regrafted, or was unable to have an implant placed. Implant survival rates were not assessed in this study. Seventy-five patients received 86 bone grafts over a period of 7 years. Overall graft survival was 87.3% with 7 complete graft failures (8.1%) and 3 partial graft failures (4.6%). All failed grafts were of the block graft type, predominately in the anterior maxilla. The main reason for failure was secondary infection. Other complications occurred in about 27% of patients. Factors significantly increasing the risk of graft failure included use of bone block augmentation (p = 0.001), mixed autogenous/bone substitute grafts (p = 0.007) and diabetes mellitus (p = 0.006). Smoking was not found to affect graft survival. Good results were found in a series of patients treated in an oral and maxillofacial training programme. Care should be taken in regards to planning block grafts in diabetic patients.

CT scanning of the alveolar cleft deformity - a useful adjunct in the assessment of bone grafting?

CT scanning of the alveolar cleft deformity - a useful adjunct in the assessment of bone grafting?

Radiological Assessment of Bone Graft in Revision Acetabular Arthroplasty

The purpose of this study was to describe the radiological appearance of moulded cancellous bone graft used for acetabular reconstruction in revision arthroplasty of the hip. We reviewed retrospectively 48 cases with a mean follow-up of 3.5 years. The radiological study was based on: the density of the graft, the delineation line between the graft and the host bone or the presence of trabecular continuity between the graft and the acetabular bone, and the position of the cup. Increasing density of the graft was observed in 35 cases. Trabecular continuity between the graft and the host bone appeared in 9 cases, in Zone I, with a mean delay of 2.6 years. This finding was associated with the disappearance of the dense line separating the graft from the acetabular bone in 8 hips (16.6%). At a mean follow-up of 2.5 years, 4 patients showed migration of the cup; this was secondary to graft resorption in 3 cases. Only one of these patients had been reoperated on. From these observations we have made an attempt to describe the evolving appearance of the bone graft and the radiological signs that may be used to assess graft incorporation.

Assessment of Bone Grafts Used for Acetabular Augmentation in Total Hip Arthroplasty

Total hip arthroplasty was performed in 13 hips with acetabular bone grafts for secure component fixation. The incorporation and healing of acetabular bone grafts were investigated with the aid of roentgenograms, planar bone scans, and a newer scintigraphic technique, three-dimensional single photon emission computed tomography (SPECT). Conventional roentgenograms proved unreliable in evaluating bone graft reconstitution because of overlapping trabecular bone patterns of the graft and iliac wing. There was no evidence of graft failure or acetabular loosening. Bone grafts in the late follow-up group (four to seven years postoperation) exhibited normal radionuclide activity, whereas grafts less than one year postsurgery demonstrated patterns of increased activity. SPECT was helpful in producing an anatomic reconstruction of the acetabulum. The observation that bone grafts exhibited normal biological viability is crucial for ensuring secure acetabular component fixation on a long-term basis.