Prevalence of Different Bone Types on Implant Placement Site Using Cone-beam Computed Tomography Images

Dental implants are a reliable tool for the replacement of missing teeth, and the use of advanced imaging techniques for the examination of the location of implants is on the rise these days. The present study aimed to assess the frequency of different types of bone at the implant site in different age groups in Cone Beam Computed Tomography (CBCT) images.

A number of 320 CBCT images (ProMax®)  which were obtained for implant replacement were evaluated in this descriptive study. Patients were assigned to 10 groups according to age (5-year intervals) from 20-70 years old. The bone type was determined based on Zarb and Lekholm classifications. In order to determine the bone type, cross-sectional images with 1mm thickness were prepared in the most suitable place for implant placement, and the resulting images were evaluated by two observers.

Out of 1042 implant sites, 461 581 sites were in maxilla and mandible, respectively. According to Kappa statistical analysis, there was a significant inter-observers statistical correlation (82%). the most commonly observed bone types were D3, D2, D4, and D1, respectively. Bone type D3 and D1 were the most and least prevalent types in men, whereas in women, the most and least prevalent types were D3 and D1, respectively. The prevalence of D3 and D4 bone type increases with age. Moreover, D1 and D3 were the least and most prevalent bone types in younger ages, respectively.

As evidenced by the obtained results, CBCT is a reliable tool for identifying the type of bone in the implant placement area and subsequently determining the prognosis of the treatment plan.