Recent clinical studies have shown that implant placement is highly predictable with computer generated guides. However, reliability of these guides compared to conventional guides has not been tested clinically. This study aimed to compare the accuracy of reproducing planned implant positions between computer generated and conventional surgical guides using a split-mouth design.
A total of 9 patients received 2 implants each, in symmetrical locations. All implants were planned virtually using a software program and information from CT scans taken with scan appliances. Patients were randomly selected for CAD/CAM guided implant placement on their right or left side. Conventional guides were used on the contralateral side. Patients received post-operative CBCT scans. Planned and actual implant positions were compared using three dimensional analyses capable of measuring volume overlap as well as differences in angles, coronal and apical positions. Results were compared using a Mixed Model Repeated Measures ANOVA and were further analyzed using a Bartlett’s test for unequal variance (alpha = 0.05).
Implants placed with CAD/CAM and conventional surgical guides had volume overlaps between planned and actual positions of 69.7% ± 6.8% and 48 ± 16.2%, respectively. This measurement was a statistically significant difference (p < 0.05). Coronal horizontal differences also showed significance (p < 0.05) with CAD/CAM measuring 0.55 mm ± 0.24 mm and conventionally guided implants 1.22 mm ± 0.62 mm. Apical horizontal distance significantly (p < 0.05) showed CAD/CAM to be more accurate than conventional guides (0.93 mm ± 0.62 mm and 2.03 mm ± 0.95 mm, respectively). Other measurements made did not show statistical significance.
Implants placed using CAD/CAM surgical guides provided more accuracy in a lateral direction than conventional guides. In addition, CAD/CAM guides were more consistent in their deviation from the planned placements than conventional guides. Further research, including a larger patient population and multiple consecutive implants, is needed.