In implantology procedures, one of the key factors determining implant success is the condition and density of bone at the placement site. For initial assessment, dentists must accurately understand bone dimensions and characteristics—both quantitatively and qualitatively—in order to select appropriate implant size and perform bone preparation procedures (such as bone grafting or sinus lift) if necessary. Cone Beam Computed Tomography (CBCT) has become a popular choice due to its ability to provide high-resolution three-dimensional images of maxillofacial structures with lower radiation doses compared to conventional CT.
Basic Research: Comparison of CBCT Measurements vs Actual Objects
Research conducted by FKG UGM student Ratihana Nurul Indias under the supervision of Dr. drg. Rurie Ratna Shantiningsih., MD.Sc., Dr. drg. Rini Widyaningrum, M.Biotech., and Prof. Dr. drg. Munakhir Mudjosemedi, S.U., published in Jurnal MKGI FKG UGM, investigated the accuracy of measurements obtained from CBCT images compared to actual object measurements (dry mandibular specimens).
Methods
- Samples consisted of 40 CBCT images of dry mandibular specimens with metal markers attached for measurement.
- Measurements were taken horizontally, vertically, and obliquely on CBCT images using specialized software (Volux 3D dental CT software).
- CBCT measurements were then compared with direct measurements of the actual objects using the Wilcoxon Signed Rank statistical test.
Results
- There were significant differences (p < 0.05) between measurements on CBCT images and actual object measurements, except in some oblique measurements not involving the anterior mandibular base.
- Maximum distortion was approximately 8% in panoramic measurements on CBCT, with distortion values varying depending on mandibular measurement location.
Implications for Implantology
- Accurate measurement of bone dimensions (including height and width) is crucial in selecting implant diameter and length to ensure stable and safe placement without risking penetration of vital anatomical structures such as the inferior alveolar nerve canal.
- Distortion of up to 8% may lead to inappropriate implant size selection, potentially resulting in integration failure or infection if the implant is too long or too wide, or unable to support occlusal load.
- Therefore, CBCT use must be accompanied by an understanding of its accuracy limitations and the application of safety margins in implant design.
There are several significant differences (p<0.05) between the metal marker distance on the CBCT image and the actual object on the dry mandible preparation, except for oblique measurements without involving the mandibular base in the anterior part of the mandible. The highest average distortion in the panoramic view of the CBCT image in this study was 8%, and the distortion value was different in each part of the mandible.
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CBCT is a highly valuable tool in implantology because it provides high-resolution three-dimensional imaging with relatively low radiation. However, research findings indicate differences between CBCT measurements and actual object dimensions, with maximum distortion of approximately 8%. Therefore, dentists must understand the limitations of CBCT accuracy in order to utilize it optimally with adequate safety margins.
References
Ratihana Nurul Indias, Dr. drg. Rurie Ratna Shantiningsih., MD.Sc., Dr. drg. Rini Widyaningrum, M.Biotech., Prof. Dr. drg. Munakhir Mudjosemedi, S.U., Perbandingan hasil pengukuran pada citra Cone Beam Computed Tomography (CBCT) dengan objek sesungguhnya, https://jurnal.ugm.ac.id/mkgi/article/view/15240
Author: Rizky B. Hendrawan | Photo: Freepik
