Influence of dental implants on the accuracy of measuring the postoperative labial alveolar bone thickness in the maxillary anterior region: An in vivo CBCT study

Abstract

Background. The accuracy of cone-beam computer tomography (CBCT) in measuring the labial alveolar bone thickness requires further evaluation. Objectives. The aim of the present study was to evaluate the impact of dental implants on the accuracy of CBCT in measuring the postoperative labial alveolar bone thickness in the maxillary anterior region. Material and methods. The distance from the labial alveolar bone surface at the bone crest level to the implant neck was measured using 2 methods. One method involved using periodontal probes during an immediate implant surgery, while the other employed the CBCT scans obtained immediately postoperation. Results. Twenty patients were recruited from the Department of General Dentistry at the Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, China, from February 2023 to October 2023. In total, 20 implants with a diameter of 3.3 mm were placed surgically. The average distance from the labial alveolar bone surface at the bone crest level to the implant neck in the group of 20 patients, obtained through the intraoperative measurement, was 3.7 ±0.8 mm. The corresponding average value based on the CBCT data of the 20 patients was 3.1 ±0.6 mm. A significant difference was observed between the 2 methods (p < 0.001). The average diameter of the 20 implants measured using the CBCT scans was 4.1 ±0.4 mm, which was significantly greater than the actual implant diameter of 3.3 mm. Conclusions. The distance from the labial alveolar bone surface at the bone crest level to the implant neck, which comprises the thickness of the labial alveolar bone and the jumping gap, was smaller according to the CBCT data than the actual values obtained from intraoperative measurements. However, the average diameter of the 20 implants measured using the CBCT scans exceeded the actual implant diameter of 3.3 mm. When assessing the thickness of the labial alveolar bone around implants in the maxillary anterior region using CBCT during follow-up, a moderate underestimation of the labial bone thickness may occur.