Usefulness of MR imaging for odontogenic tumors.

MRI has become an invaluable diagnostic tool in all areas of the body. However, it has not been widely used to image odontogenic tumors of the jaw. Major advantages of MRI include excellent soft tissue contrast in the absence of ionizing radiation. Furthermore, diffusion-weighted MRI and dynamic contrast-enhanced MRI can be used as functional imaging techniques for assessing tissue biology. In this review article, we present representative MR images of several types of odontogenic tumors, and discuss MR imaging characteristics useful for differential diagnosis.

Differences in the Clinical Characteristics of Persistent Idiopathic Facial Pain (Atypical Odontalgia) Patients with or Without Neurovascular Compression of the Trigeminal Nerve.

BACKGROUND: Persistent idiopathic facial pain (PIFP) is the unexplained pain along the territory of the trigeminal nerve, including nonorganic tooth pain called atypical odontalgia (AO). Though PIFP is debilitating to patients' livelihood and well-being, its pathophysiology remains poorly understood. Although neurovascular compression (NVC) of the trigeminal nerve is known to be associated with trigeminal neuralgia (TN), the relationship between NVC and other orofacial pains has not been fully elucidated. METHODS: In this study, we investigated the differences in the characteristics of PIFP (primarily AO) patients in the presence or absence of NVC. A retrospective analysis was performed on data from 121 consecutive patients who had been diagnosed with unilateral PIFP according to the criteria of the International Classification of Headache Disorders (ICHD)-3 and underwent magnetic resonance imaging scans of the head. RESULTS: In the group without NVC, characteristic findings were significant for psychiatric morbidity, somatization, and pain disability, when compared with the group with NVC. Furthermore, the group without NVC exhibited significant headache, noncardiac chest pain, shortness of breath, and pain catastrophizing. CONCLUSIONS: These results suggest that PIFP patients can be divided into two groups: one consistent with a neuropathic pain phenotype when NVC is present and a functional somatic symptom phenotype when presenting without NVC. Our findings may enable a more precise understanding of pathophysiology of PIFP and lead to better treatment strategies.

Morphological comparison of artificial teeth position utilising denture space in glossectomy patients.

OBJECTIVE: This study aimed to compare the denture space of edentulous glossectomy patients with that of a control group from the perspective of artificial teeth positioning by using three-dimensional techniques. BACKGROUND: It is known that the shape of the denture space may be affected by tongue resection or reconstruction. However, the details of artificial teeth positioning in these patients remain unclear. MATERIALS AND METHODS: Six edentulous glossectomy patients aged 73-83 years and six normal participants aged 74-85 years participated in the study. Piezography was used to elucidate the characteristics of the denture space. For visualisation, piezographic records were scanned using cone beam computed tomography and the data were converted into stereolithographic format. Three-dimensional images of piezographic records were then constructed. Bucco-lingual widths of the mandibular occlusal surface were reproduced, and the camber line of the occlusal surface was set so as to simulate the position of the artificial teeth. The maximum chord of the occlusal surface on the left and right sides was recorded and measured. The discrepancy and ratio of the larger chord to the smaller chord between the right and left sides was calculated and subjected to statistical analyses using the Mann-Whitney U test. RESULTS: There were significant differences in discrepancy and ratio between the left and right in the control group and the glossectomy patients (P Ë‚ .01). The glossectomy patients showed a greater discrepancy and ratio than the control group. CONCLUSIONS: The simulated artificial teeth positions on the occlusal surface between the right and left side were asymmetric in glossectomy patients.

Application of diffusion kurtosis imaging to odontogenic lesions: Analysis of the cystic component.

PURPOSE: To assess the feasibility of applying diffusion kurtosis imaging (DKI) to common odontogenic lesions and to compare its diagnostic ability versus that of the apparent diffusion coefficient (ADC) for differentiating keratocystic odontogenic tumors (KCOTs) from odontogenic cysts. MATERIALS AND METHODS: Altogether, 35 odontogenic lesions were studied: 24 odontogenic cysts, six KCOTs, and five ameloblastomas. The diffusion coefficient (D) and excessive kurtosis (K) were obtained from diffusion-weighted images at b-values of 0, 500, 1000, and 1500 s/mm2 on 3T magnetic resonance imaging (MRI). The combination of D and K values showing the maximum density of the probable density function was estimated. The ADC was obtained (0 and 1000 s/mm2 ). Values for odontogenic cysts, KCOTs, and ameloblastomas were compared. Multivariate logistic regression modeling was performed to assess the combination of D and K model versus ADC for differentiating KCOTs from odontogenic cysts. RESULTS: The mean D and ADC were significantly higher for ameloblastomas than for odontogenic cysts or KCOTs (P < 0.05). The mean K was significantly lower for ameloblastomas than for odontogenic cysts or KCOTs (P < 0.05). The mean values of all parameters for odontogenic cysts and KCOTs showed no significant differences (P = 0.369 for ADC, 0.133 for D, and 0.874 for K). The accuracy of the combination of D and K model (76.7%) was superior to that of ADC (66.7%). CONCLUSION: Use of DKI may be feasible for common odontogenic lesions. A combination of DKI parameters can be expected to increase the accuracy of its diagnostic ability compared with ADC. J. Magn. Reson. Imaging 2016;44:1565-1571.

Localizing the mandibular canal on dental CT reformatted images: usefulness of panoramic views.

PURPOSE: The aim of this study was to compare panoramic and paraxial views of dental CT reformatted images to detect the mandibular canal, and to evaluate the usefulness of the dental CT software function of "Outlining the Mandibular Canal in the Panoramic View". METHODS: One hundred and fifty-five patients (310 sides), who underwent multi-slice computed tomography examination for pretreatment planning of dental implant were analyzed. After scanning, two types of dental CT reformatted image, panoramic and paraxial views were obtained. Two oral radiologists evaluated both views for the visibility of the mandibular canal using a 5-point rating scale: score 5, 100-80% visible, to score 1, 20-0% visible. The visibility scores of the two views were evaluated and compared by Wilcoxon's signed rank test. RESULTS: The mean ± standard deviations of panoramic and paraxial views were 4.2 ± 1.1 and 3.5 ± 1.2, respectively, and the former was significantly higher than the latter (p < 0.001). On the basis of these results, we attempted to apply the function of "Outlining the Mandibular Canal in the Panoramic View" to cases with poor visibility of the canal (score 1, 2 or 3) on paraxial views. Consequently, we could reduce the number of such cases from 128 (41%) to 56 (18%). CONCLUSIONS: The detectability of the mandibular canal was significantly higher in panoramic views than in paraxial views. Using the function of "Outlining the Mandibular Canal in the Panoramic View", the precision for identifying the canal on paraxial views was considered to be improved.

Risk factors for posttreatment mastoid cellulitis in patients with oral malignancy.

OBJECTIVES: To investigate the possible risk factors for mastoid cellulitis after treatment in patients with oral cancer. METHODS: Patients with oral cancer who underwent preoperative and postoperative contrast-enhanced computed tomography (CECT) between January 2017 and March 2020 were retrospectively evaluated. Using an image reporting system, cases with reports containing the keyword "mastoid cellulitis" were registered in the mastoid cellulitis group. Fifty patients with oral cancer who did not develop mastoid cellulitis were randomly selected as the control group. Information concerning age, sex, location, and histopathological type of the primary tumor, presence or absence of cervical lymph node metastasis, and treatment methods were obtained from the hospital's electronic medical records to investigate the association between these factors and the occurrence of mastoid cellulitis. RESULTS: Statistically significant differences were observed in the following factors: age (p = 0.004), primary tumor site (p < 0.001), histopathological type (p = 0.032), radiotherapy (p < 0.001), and chemotherapy (p < 0.001). Logistic regression analysis revealed that maxillary tumors (p < 0.001), histopathological type (p = 0.047), and radiotherapy (p = 0.0301) were significantly associated with the occurrence of mastoid cellulitis. CONCLUSIONS: In oral cancer, the risk of postoperative mastoid cellulitis was higher in patients with a maxillary tumor, histopathology other than squamous cell carcinoma, and history of radiotherapy.

The magnetic resonance imaging characteristics of radicular cysts and granulomas.

OBJECTIVES: Limited studies have differentiated radicular cysts and granulomas with MRI. Therefore, we investigated the MRI characteristics of the two lesions and clarified features for distinguishing between them. METHODS: We collected data of 27 radicular cysts and 9 granulomas definitively diagnosed by histopathology and reviewed the fat-saturated T2 weighted, T1 weighted, and contrast-enhanced fat-saturated T1 weighted images. We measured the maximum diameter and apparent diffusion coefficient values of the lesions. We employed Fisher's exact test, the Mann-Whitney U test, and independent t-tests to compare the two lesions and created a decision tree for discriminating between them. RESULTS: There were significant differences between radicular cysts and granulomas with respect to five imaging characteristics-signal intensity of the lesion centre on fat-saturated T2 weighted images; signal intensity, texture, and contrast enhancement of the lesion centre on contrast-enhanced fat-saturated T1 weighted images; and maximum diameter of the lesion. The cut-off diameter for radicular cysts was 15.9 mm. The area under the receiver operating characteristic curve, sensitivity, and specificity were 0.971, 85.2%, and 100%, respectively. CONCLUSIONS: From the decision tree analysis, maximum diameter, lesion centre contrast enhancement on contrast-enhanced fat-saturated T1 weighted images, and lesion centre signal intensity on fat-saturated T2 weighted images were important for discriminating between radicular cysts and granulomas.

Magnetic resonance imaging of methotrexate-related lymphoproliferative disorder with a chief complaint of oral symptoms.

OBJECTIVES: To determine the magnetic resonance imaging (MRI) features of methotrexate-related lymphoproliferative disorder (MTX-LPD) in the oral cavity of a patient with a chief complaint of oral symptoms. METHODS: We included six patients who visited our hospital between November 2014 and November 2019, histopathologically diagnosed with MTX-LPD. All images were examined using 3 T MRI and reviewed by two radiologists. RESULTS: Masses were detected in five cases; all masses demonstrated signal hypointensity and homogeneous signal hyperintensity on T1- and T2-weighted images with fat suppression. Homogeneous enhancement with fat suppression was evident on post-contrast T1-weighted imaging. We performed dynamic contrast-enhanced MRI in three cases and observed early enhancement with a low washout ratio pattern in all cases. Four patients underwent diffusion-weighted MRI and revealed low mean apparent diffusion coefficient (ADC) of 0.57 (range 0.5-0.65) × 10-3 mm2/s. CONCLUSIONS: We reported on the imaging characteristics of six rare cases of MTX-LPD in the oral cavity. Homogeneous hyperintensity on fat-suppressed T2-weighted images and low ADC values are possible features of MTX-LPD. Moreover, MTX-LPD can be differentiated from other carcinomas in the oral cavity.

Differentiation of cystic lesions in the jaw by conventional magnetic resonance imaging and diffusion-weighted imaging.

OBJECTIVES: This study aimed to determine the discrimination power of apparent diffusion coefficient (ADC) for cystic lesions in the jaw using MRI. METHODS: We selected 127 cystic lesions, comprising dentigerous cysts (DCs), odontogenic keratocysts (OKCs), and unicystic ameloblastomas (UABs), from our MRI database examined by 3T MRI, including diffusion-weighted imaging sequences, and we reviewed their imaging characteristics. We attempted to discriminate the three types of lesions by ADC values with receiver operator characteristic analysis; however, satisfactory results were not obtained for differentiation between DC and OKC. Therefore, we performed a decision tree analysis. RESULTS: The imaging characteristics of the lesions were significantly different according to Fisher's exact test, except for differences in sex. The ADC values statistically discriminated the lesions of DC and UAB, OKC and UAB, but not DC and OKC. Thus, differentiation was performed by a decision tree for DC and OKC by evaluating the following points: the attached tooth condition, signal intensity on the T1 weighted image (T1SI), ADC value, and the cyst site. However, cases showing hypo- or isointense T1SI with an ADC value under 1.168 × 10-3 mm2/s were difficult to differentiate. CONCLUSION: The ADC value helped distinguish UAB from both DC and OKC, but not DC from OKC. However, the decision tree based on ADC value, tooth contact status, and T1SI helped differentiate DC and OKC to some extent.

Dual-time-point fluorodeoxyglucose positron emission tomography for diagnosis of cervical lymph node metastases in patients with head and neck squamous cell carcinoma.

OBJECTIVE: The purpose of this study was to evaluate whether dual-time-point fluorodeoxyglucose positron emission tomography/computed tomography image can improve nodal diagnosis in patients with head and neck squamous cell carcinoma (HNSCC). METHODS: One hundred six HNSCC patients were enrolled. Positron emission tomography/computed tomography images were obtained twice: 1 and 2 hours after fluorodeoxyglucose injection. Maximum standardized uptake value (SUVmax) and SUVmax increasing rate (SUV-IR) were compared with the histopathologic findings to determine the optimal cutoff for nodal diagnosis. RESULTS: Using early-phase image, SUVmax ≧ 2.75 was considered as optimal criterion. When using delayed-phase, SUVmax ≧ 3.5 was optimal. There was no significant difference between these criteria. Maximum standardized uptake value IR ≧ 8.0 (10/s) was considered as optimal, although it provided relatively low sensitivity (66%) and specificity (82%). However, combined criterion of SUVmax ≧ 3.5 in delayed-phase or SUV-IR ≧ 8.0 (10/s) significantly improved the specificity (90%) and accuracy (89%) without decreasing the sensitivity (84%). CONCLUSIONS: Using delayed-phase image combined with SUV-IR can improve the nodal diagnosis in HNSCC patients.

Longitudinal MRI follow-up of rheumatoid arthritis in the temporomandibular joint: importance of synovial proliferation as an early-stage sign.

This article describes longitudinal magnetic resonance imaging (MRI) observations in a patient with rheumatoid arthritis of the temporomandibular joint. The characteristic findings included marked synovial proliferation, which was observed before the onset of severe bone destruction. MRI is considered to provide valuable information for the early detection of rheumatoid arthritis of the temporomandibular joint.

Effective dose estimation in cone-beam computed tomography for dental use by Monte-Carlo simulation optimizing calculation numbers using a step-and-shoot method.

OBJECTIVE: The objective of this study was to perform effective dose estimation in cone-beam CT for dental use (CBCT) using a Monte-Carlo simulation employing a step-and-shoot method as well as to determine the optimal number of steps. METHODS: We simulated 3DX Accuitomo FPD8 as a CBCT model and estimated the effective doses of a large and a small field of view (FOV) examination against the virtual Rando phantom using a particle and heavy ion transport code system. We confirmed the results compared to those from a thermo-luminescence dosemeter (TLD) system in a real phantom and investigated how the reduced angle calculations could be accepted. RESULTS: The effective doses of both FOVs estimated with each one degree were almost the same as those estimated from the TLD measurements. Considering the effective doses and the itemized organ doses, simulation with 5° and 10° is acceptable for the large and small FOV, respectively. We tried to compare an effective dose with a large FOV as well as with multiple small FOVs covering the corresponding area and found that the effective dose from six small FOVs was approximately 1.2 times higher than that of the large FOVs. CONCLUSION: We successfully performed a Monte-Carlo simulation using a step-and-shoot method and estimated the effective dose in CBCT. Our findings indicate that simulation with 5° or 10° is acceptable based on the FOV size, while a small multiple FOV scan is recommended from a radiation protection viewpoint.

Incidence of hypercementosis in mandibular third molars determined using cone beam computed tomography.

PURPOSE: This study was conducted to investigate the incidence and predictors of hypercementosis in mandibular third molars using cone beam computed tomography. METHODS: Using a retrospective approach, 1,160 cone beam computed tomography image sets were analyzed. Two oral radiologists independently evaluated the image sets based on four severity grades: 0, no hypercementosis around the root; 1, hypercementosis surrounding less than half of the root surface; 2, hypercementosis surrounding more than half of the root surface; and 3, hypercementosis surrounding the entire root surface. Hypercementosis was identified as a dark or light layer. Statistical analyses of relationships between hypercementosis incidence and possible predictors (e.g. age, sex, impaction, and occlusion) were performed using chi-square test or Fisher's exact test; logistic regression was used for multivariate analysis. RESULTS: The severity of hypercementosis increased with age, and the incidences were as follows: ≤19 years, 0%; 20-24 years, 14.1%; 25-29 years, 57.7%; 30-39 years, 83.0%; 40-49 years, 92.7%; 50-59 years, 93.4%; and ≥60 years, 96.8%. CONCLUSION: The observed incidences of hypercementosis were relatively higher than in previous studies, and the incidence was significantly lower for occluded teeth than for non-occluded teeth.

Applying the paralleling technique in intraoral periapical radiographs for Japanese patients by analyzing CT images.

OBJECTIVES: The aim of this study was to investigate the size of the teeth and palatal heights to determine if it is possible to apply the paralleling technique in the upper molar region in Japanese patients. METHODS: The medical computed tomography (CT) data of ten patients were analyzed. A minimum intensity projection image with 8-mm slice thickness was created for each second premolar, first molar, and second molar tooth. We traced the tooth, the alveolar bone, the plate bone surface, and the cheek skin surface on a tracing paper. Tooth length (TL), palatal height (PH), distance between a tip of the cheek and each tooth (D1), and distance between each tooth and the receptor (D2) were measured. The measurements were performed by two observers, and the measurements were repeated twice by each observer. Two potential situations were considered for application of the paralleling technique. RESULTS: We analyzed whether there was a possibility for application of the paralleling technique comparing the TL and the PH for each case by considering the magnification rate calculated from D1 and D2, the palatal mucosa thickness, and the safety margin within the resultant image. The data suggested that applying the paralleling technique was impossible in 95% of cases. In the cases where application of the paralleling technique was impossible, the incident angle of X-ray increased by 31.6°. CONCLUSIONS: We concluded that the paralleling technique could not be applied in Japanese patients due to insufficient space for the image receptor in the upper maxilla region.

Evaluation of streak metal artifacts in cone beam computed tomography by using the Gumbel distribution: a phantom study.

OBJECTIVE: The aim of this study was to confirm whether streak metal artifacts (SMAs) between titanium implants on cone beam computed tomography (CBCT) images could be evaluated by using the Gumbel distribution (GD). Moreover, the influence of different scan settings on SMAs was investigated. STUDY DESIGN: An iodine solution simulating dentin was placed between 2 titanium rods in an acrylic phantom. It was scanned by using CBCT at 2 settings with nearly equivalent exposure doses (90 kV, 7 mA; 78 kV, 10 mA). The images were analyzed, and the dependence of the voxel values in SMAs on GD was investigated with the coefficient of determination (r2). The location parameters, indicating the strength of the SMAs, were calculated for each scan setting and evaluated with the Mann-Whitney U test. Significance was established at p = .05. RESULTS: The SMAs on CBCT images depended on GD (r2 ≥ .959). The SMAs with the 78 kV, 10 mA settings were significantly smaller than those with the 90 kV, 7 mA settings (p < .01). CONCLUSIONS: SMAs on CBCT images could be evaluated by using methods based on GD. The strengths of metal artifacts varied with changes in scan settings, even at nearly equivalent exposure doses.

Effective combination of 3 imaging modalities in differentiating between malignant and benign palatal lesions.

OBJECTIVE: The aim of this study was to evaluate whether computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography/computed tomography (PET/CT) can effectively differentiate between malignant and benign palatal lesions. STUDY DESIGN: In total, 59 patients with palatal lesions (32 malignant and 27 benign), who underwent CT, MRI, and/or PET/CT imaging examinations and had histopathological diagnoses, were divided into an analysis group (n = 46) and a validation group (n = 13). Bone changes adjacent to the lesion, MRI signal intensity, apparent diffusion coefficient (ADC), time to peak enhancement (Tpeak), and maximum standardized uptake values (SUVmax) were evaluated in the analysis group. Diagnostic performance was individually assessed for each parameter for differentiating between malignant and benign lesions. A diagnostic decision tree was constructed by using useful parameters and its accuracy tested in the validation group. RESULTS: The frequency distribution of bone change types and Tpeak differed significantly between malignant and benign lesions. The ADC of malignant lymphoma was significantly lower than that of other lesions. The other parameters did not distinguish between lesion types. The accuracy of the decision tree, constructed by using bone change types, ADC, and Tpeak, was 87.5%. CONCLUSIONS: Bone change types, ADC values, and Tpeak are useful for differentiating between malignant and benign palatal lesions.

Distrontium Cerate as a Radiopaque Component of Hydraulic Endodontic Cement.

This study aimed to synthesize distrontium cerate (2SrO·CeO2: S2Ce) and evaluate its properties as an alternative component of the endodontic cement. S2Ce cement was prepared through calcination of strontium hydroxide and cerium carbonate. Subsequently, the crystal phase was confirmed using X-ray diffraction. S2Ce cement exhibited a rapid setting time (121 min) and achieved a high compressive strength (72.1 MPa) at 1 d after mixing, comparable to the compressive strength of a commercial mineral trioxide aggregate (MTA) cement (ProRoot MTA) after 28 d post mixing. However, the compressive strength decreased after 28 d of storage when the W/P ratio was 0.30-0.40 (p < 0.05). Ion dissolution test of the S2Ce cement showed that strontium ions were released after immersion in water (5.27 mg/mL after 1 d), whereas cerium dissolution was not detected. S2Ce exhibited approximately three times higher radiopacity (9.0 mm aluminum thickness equivalent) compared to the commercial MTA (p < 0.05). These findings suggest that S2Ce is a possible component for hydraulic endodontic cement that demonstrates a rapid setting and high radiopacity.

MRI before biopsy correlates with depth of invasion corrected for shrinkage rate of the histopathological specimen in tongue carcinoma.

The purpose of this study was to evaluate which radiological depth of invasion (r-DOI) measurement is the most concordant to clinical DOI (c-DOI) derived from correction for the shrinkage rate of the histopathological specimens. We retrospectively reviewed 128 patients with tongue carcinoma who had undergone glossectomy between 2006 and 2019. At first, the width shrinkage rate during formalin fixation and preparation process of histopathological specimens was evaluated. From the shrinking rates, a formula to calculate c-DOI from pathological DOI (p-DOI) was developed. The correlation between c-DOI and r-DOI was evaluated. The specimen shrinkage rate during the histopathological specimen preparation process was 10.3%. Based on that, we yielded the correct formula for c-DOI based on p-DOI and preparation shrinkage rate: c-DOI = p-DOI × 100/89.7. The regression equations for the association of c-DOI with r-DOI measured by ultrasound (n = 128), MRI before biopsy (n = 18), and MRI after biopsy (n = 110) were y = 1.12 * x + 0.21, y = 0.89 * x - 0.26, and y = 0.52 * x + 2.63, respectively, while the coefficients of determination were 0.664, 0.891, and 0.422, respectively. In conclusion, r-DOI using MRI before biopsy most strongly correlated with c-DOI.

Clinical guidelines for the application of panoramic radiographs in screening for osteoporosis.

Osteoporotic fractures are associated with an increased risk of subsequent fractures, a higher rate of mortality, and incremental medical costs. Incidental findings, which include some measurements related to the mandibular inferior cortex and the alveolar trabecular bone pattern of the mandible determined on panoramic radiographs, are considered to be a useful tool for identifying asymptomatic individuals at risk of having osteoporosis and/or fragility fractures. We undertook a worldwide literature survey and present the following clinical recommendations. Postmenopausal female dental patients with a mandibular inferior cortical width of less than 3 mm on panoramic radiographs may be at risk of having low skeletal bone mineral density (BMD) or osteoporosis, but not fragility fractures. In addition, those with a severely eroded mandibular inferior cortex may have an increased risk of having low skeletal BMD, osteoporosis, and fragility fractures. The alveolar trabecular bone pattern of the mandible might be useful for identifying female dental patients at risk of having fragility fractures, although further investigation is necessary to confirm this possibility. These incidental findings on panoramic radiographs, when used for identifying asymptomatic postmenopausal female patients at risk of having osteoporosis in general dental practice, may be helpful in reducing the incidence of first fractures, with a consequent reduction in the secondary fractures, medical costs, and mortality associated with osteoporotic fragility fractures, without incurring any additional cost.

Postoperative morphological changes over time of vascularized scapular bone used for mandibular reconstruction: A retrospective cohort study.

BACKGROUND: Currently, sequential morphological changes of vascularized scapular bone for mandibular reconstruction have remained unreported. METHODS: We retrospectively analyzed 18 patients with defects on the lateral segment of the mandible who underwent postoperative computed tomography (CT) scanning at 1, 6, 12, and 24 months postoperatively. Using the cross-sectional coronal CT images during each assessment, we measured the height and thickness of the grafted scapular bone at points 10 and 30 mm away from the mesial segment and evaluated their differences over time. Then, the relationship between the morphological changes of the grafted scapular bone and the distance from the mesial bone segment, the number of occlusal supports on the contralateral side of the mandible, and the correlation of sex and age were evaluated. RESULTS: The height of the grafted scapular bone decreased by approximately 11% and its thickness increased by 14% within 24 months postoperatively. The bone thickness increase was greater at point 30 mm from the mesial bone segment. Patients with two occlusal contacts (premolar and molar) on the contralateral side had a significantly higher rate of bone thickness increase. Furthermore, the graft morphology was not associated with age or sex. CONCLUSION: A vascularized scapular bone thickens over time, which depends on the distance from the mesial bone segment and the occlusal contact regions on the contralateral side of the mandible.