A radiological method to evaluate alveolar bone regeneration in the Chacma baboon (Papio ursinus)

The evaluation of alveolar bone healing may have a role in dental implantology, in prosthodontics in the post-extraction phase and in monitoring fracture repair. There are several radiological techniques described to evaluate alveolar bone regeneration. However, most are expensive and time consuming.

To develop and evaluate a radiological method utilising readily available equipment to measure alveolar bone regeneration.

An apparatus was designed to enable the acquisition of standardized x-ray images, consisting of a disposable impression tray, digital positioning system, aluminum step wedge, digital x-ray sensor, Rinn apparatus and laboratory putty. Bone biopsies were collected from each oral quadrant in each of five Chacma baboons (Papio ursinus). Accurately standardised x-ray images of the biopsy sites were taken pre-operatively, directly post-operatively and again after three and six week intervals. These images were analysed using a graded histogram provided in a computer software program.

The average gray-scale value on the histogram of the selected biopsy area was determined on the series of standardised images. The average values for the three biopsied sites per quadrant were expressed as percentages of pre-operative density. The results ndicated a mean ncrease of 6.3% (+/- 1.4%) (mean +/- 1 SEM) in bone density after three weeks and 12.6% (+/- 1.7%) six weeks post-operatively.

A standardised radiologica examination method was developed which, together with a computer ised evaluation technique, could be applied to accurately determine relative bone density. This method was shown to provide comparative bone density values during the regeneration process of alveolar bone over a six week period.