Background Quantitative MRI can detect early changes in cartilage biochemical components, but its routine clinical implementation is challenging. Purpose To introduce a novel technique to measure T1 and T2 along radial sections of the hip for accurate and reproducible multiparametric quantitative cartilage assessment in a clinically feasible scan time. Study Type Reproducibility, technical validation. Subjects/Phantom A seven‐compartment phantom and three healthy volunteers. Field Strength/Sequence A novel MR pulse sequence that simultaneously measures proton density (PD), T1, and T2 at 3 T was developed. Automatic positioning and semiautomatic cartilage segmentation were implemented to improve consistency and simplify workflow. Assessment Intra‐ and interscanner variability of our technique was assessed over multiple scans on three different MR scanners. Statistical Tests For each scan, the median of cartilage T1 and T2 over six radial slices was calculated. Restricted maximum likelihood estimation of variance components was used to estimate intrasubject variances reflecting variation between results from the two scans using the same scanner (intrascanner variance) and variation among results from the three scanners (interscanner variance). Results The estimation error for T1 and T2 with respect to reference standard measurements was less than 3% on average for the phantom. The average interscanner coefficient of variation was 1.5% (1.2–1.9%) and 0.9% (0.0–3.7%) for T1 and T2, respectively, in the seven compartments of the phantom. Total scan time in vivo was 7:13 minutes to obtain PD, T1, and T2 maps along six radial hip sections at 0.6 × 0.6 × 4.0 mm3 voxel resolution. Interscanner variability for the in vivo study was 1.99% and 5.46% for T1 and T2, respectively. in vivo intrascanner variability was 1.15% for T1 and 3.24% for T2. Data Conclusion Our method, which includes slice positioning, model‐based parameter estimation, and cartilage segmentation, is highly reproducible. It could enable employing quantitative hip cartilage evaluation for longitudinal and multicenter studies. Level of Evidence: 1 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2019;50:810–815.

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Background: Age and gender have important effect on Gonial angle, ramus height and bigonial width. Objective: To evaluate the changes in gonial angle, bigonial width and ramus height measured from panoramic radiographs, in relation to age and gender. Patients and Methods: Fifty digital panoramic radiographs were evaluated (25 male and 25 female). The patients classified into 5 groups according to age, starting from 20 years old to 60 years and above with ten years interval . The gonial angle, ramus height and bigonial width were measured by digital panoramic radiographs by using Planmeca Romix software program. Results: Gonial angle, ramus height and Bigonial width increased with age. Gonial angle of the left side was greater than the right side and females had larger gonial angle compared to male. The measurements show that the ramus height was greater on the right side than the left side, greater ramus height and bigonial width in male patients. Conclusion: Gonial angle, ramus height and bigonial width are the most important and widely used radiographic landmarks in orthodontic tracing for evaluation of growth pattern and treatment planning. It's also used as a basic reference for forensic dentistry and for comparison with other nationalities and races.

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