1st INTERNATIONAL TURKISH JAPANESE DENTAL CONGRESS 2nd ANKARA-OSAKA UNIVERSITY DENTAL WORKSHOP, Ankara, Turkey, 24 - 26 June 2021, pp.84-85
Comparison of Cephalometric Radiography and Dental Volumetric Tomography Measurements of Bucco-Lingual Angle and Bone Thicknesses in Mandibular Symphyseal Area
Oğuzhan Baydar1 , Erinç Önem1 , B. Güniz Baksı1
1Ege University, School of Dentistry, Department of Oral and Maxillofacial Radiology, Izmir, Turkey
Introduction/Purpose: One of the sites with the highest risk of clinically important complications is anterior mandibular region in terms of implant or advanced surgical applications due to its complex anatomical features, insufficient bone volume, and anastomoses of vital anatomic structures. Accordingly, determination of the angle and dimensions of bone at implant recipient site in the symphyseal area has a vital importance both for the formation of osseointegration and long-term clinical success. Therefore, the aim of this study was to compare the buccal concavity, lingual- and the tooth-inclination angles of the mandibular symphysis area, as well as buccal & lingual cortical bone and total bone thickness measurements using cephalometric radiography (CR) and dental volumetric tomography (DVT) images.
Method: One hundred patients justifying both CR and DVT exposures for various reasons were included in the study. Images were obtained with the Kodak 9000 3D DVT system (Kodak Carestream Health, Trophy, France) and also with the KaVo OP 3D cephalometric machine (KaVo OP 3D™ Biberach, Germany). Parameters particularly important for implant planning such as buccal-concavity, lingual- and tooth-inclination angles as well as buccal, lingual, and total bone thickness measurements were performed on all images using the measurement tool provided by the system software. Two observers performed the measurements independently and mean of the measurements were used for statistical analysis. While magnification correction was made on CR measurements, DVT measurements were used directly. Comparison of the measurements and the imaging methods were done using paired- and Wilcoxon t-tests. Inter-observer reliability was evaluated with the intra-class correlation coefficient.
Findings: The mean buccal concavity angles measured on CR was 141.7° ± 7.73, while it was 144.6° ± 6.6 on DVT images. Mean value of lingual inclination angle measurements was 68.6° ± 8.1 on CR and 70.6° ± 14.5 on DVT images, respectively. The mean value of the tooth inclination angle was 71.1° ± 9.4 for CR and 74.7° ± 8.37 for DVT. The mean of total bone thickness measured on CR was 6.7 ± 1.8 mm, while it was 6.3 ± 1.9 mm on DVT. The mean of buccal & lingual cortical bone thicknesses as measured on CR were 1.6 ± 0.4 mm and 1.7 ± 0.4 mm respectively, while identical measurements on DVT were 1.1 ± 0.38 mm 1.6 ± 0.4 mm. There was a significant difference between two imaging methods in buccal-concavity and tooth-inclination angles as well as buccal and total bone thicknesses (p <0.05). However, no difference was obtained in lingual-inclination angle and lingual bone thickness measurements (p>0.05). Inter-observer reliability ranged between 0.86 and 0.99.
Conclusion: Based on the present data, CR can be reliable for measurements of lingual inclination angle and lingual cortical bone thickness in the mandibular symphyseal region. However, CR measurements significantly deviated from DVT measurements for buccalconcavity, tooth inclination angle and total bone thickness of the anterior mandibular region. Accordingly, 3-D imaging of the mandibular symphysis is recommended before implant surgery and/or graft operations to reduce the risk of complications.
Keywords: Cephalometric Radiography, Dental Volumetric Tomography, Mandibular Symphyseal Area