Abstract
OBJECTIVES: To compare the measurement accuracy of cone-beam computed tomography (CBCT), high-resolution ultrasound (US), and intraoral scanning (IOS) with the gold-standard direct method in the measurement of peri-implant bone defects. METHODS: Forty standard-threaded and 38 aggressive-threaded (Aggressor) implants-identical in diameter and length (4.3/10 mm) but differing in macro-thread design-were placed into bovine rib bones in vitro. Dehiscence, 2/3-wall, and 4-wall (circumferential) defects were prepared around the implants. Each defect was measured for maximum width, depth, and height using CBCT, US, IOS, and direct manual measurement. Analyses were performed using the general linear model (ANOVA). A P-value < .05 was considered statistically significant. RESULTS: Intra-operator and inter-operator agreement showed high reliability (Gage R&R below 10%). For maximum width, defect type (F = 894.81, P < .001), method (F = 6.76, P < .001), and implant type (F = 5.39, P = .021) were significant. For maximum depth, defect type (F = 861.12, P < .001) and method (F = 3.39, P = .018) were significant. For maximum height, method (F = 12.62, P < .001) and defect type (F = 38.91, P < .001) were significant. The model demonstrated high explanatory power for width (R2 = 75.9%) and depth (R2 = 76.6%) measurements but lower for height (R2 = 20.7%). CBCT provided the most consistent results relative to direct measurements, followed by US, whereas IOS showed greater deviations. CONCLUSIONS: CBCT showed the highest agreement with direct measurements, followed by US, while IOS exhibited greater variability. Defect type and measurement modality were the primary determinants of accuracy. These findings indicate that CBCT and US can be considered reliable tools for assessing peri-implant bone defects.