Furcation area and root proximity of molars as a risk indicator of periodontitis: a cone­beam computed tomography-based study.

OBJECTIVES: This study assessed the root proximity in molars and the furcation area (FA) in the first root separation point (RSP) using cone­beam computed tomography (CBCT) and evaluated the association between the furcation area of molars and periodontal status of the patients. METHODS: A total of 264 molar teeth in 66 participants were included in the study. The control group consisted of 110 molar teeth of participants, and 154 molar teeth were included in periodontitis group, which consisted of only stage II and III periodontitis patients. FA, RSP, and root proximities were measured in axial slices, and bone resorption rates were measured in sagittal slices. RESULTS: Both maxillary and mandibular molar groups had significantly less FA in periodontitis group than in controls (p < 0.005), and there were significant relationships between the degree of bone resorption in molars and FA and furcation grades (p < 0.001). According to regression analysis, the risk of periodontitis increased by 1.011 times as total FA decreased (p < 0.001), and periodontitis risk of maxillary molar was 1.693 times higher than mandibular molars but not found to be statistically significant (p = 0.152). When assessing the root proximity between molar teeth, maxillary molars showed significantly higher root proximity in CEJs than mandibular molars in both periodontitis and control groups (p < 0.05). CONCLUSIONS: The results indicate that the association between FA and the degree of bone resorption and root proximity of maxillary molars might be considered as a risk indicator for bone resorption in molars and might play a role during disease progression.

A Fused Deep Learning Architecture for the Detection of the Relationship between the Mandibular Third Molar and the Mandibular Canal.

The study aimed to generate a fused deep learning algorithm that detects and classifies the relationship between the mandibular third molar and mandibular canal on orthopantomographs. Radiographs (n = 1880) were randomly selected from the hospital archive. Two dentomaxillofacial radiologists annotated the data via MATLAB and classified them into four groups according to the overlap of the root of the mandibular third molar and mandibular canal. Each radiograph was segmented using a U-Net-like architecture. The segmented images were classified by AlexNet. Accuracy, the weighted intersection over union score, the dice coefficient, specificity, sensitivity, and area under curve metrics were used to quantify the performance of the models. Also, three dental practitioners were asked to classify the same test data, their success rate was assessed using the Intraclass Correlation Coefficient. The segmentation network achieved a global accuracy of 0.99 and a weighted intersection over union score of 0.98, average dice score overall images was 0.91. The classification network achieved an accuracy of 0.80, per class sensitivity of 0.74, 0.83, 0.86, 0.67, per class specificity of 0.92, 0.95, 0.88, 0.96 and AUC score of 0.85. The most successful dental practitioner achieved a success rate of 0.79. The fused segmentation and classification networks produced encouraging results. The final model achieved almost the same classification performance as dental practitioners. Better diagnostic accuracy of the combined artificial intelligence tools may help to improve the prediction of the risk factors, especially for recognizing such anatomical variations.

Cone beam computed tomography analysis of mandibular inferior cortical thickness and bone texture in cemento-osseous dysplasia.

OBJECTIVE: This study compared mandibular cortical thickness (CTh) and fractal dimension (FD) in patients with cemento-osseous dysplasia (COD) and controls, as measured with cone beam computed tomography. STUDY DESIGN: In total, 28 female patients with COD and 28 age-matched controls were selected retrospectively. Inferior cross-sectional CTh was measured at the symphysis (sCTh), anterior (aCTh), mental foramen (mfCTh), molar (mCTh), and posterior (pCTh) regions. The alternate measurement of mean CTh of the volume including buccal, lingual, and inferior cortices between the mental foramina (alternate CTh) was measured in ImageJ. FD was calculated in cortical and trabecular bone. Data were analyzed for significance of differences in CTh and FD between patient groups and for correlation of inferior and alternate CTh measurements. RESULTS: Inferior CTh values were lower overall in the patients with COD than in the controls (P = .01), specifically at sCTh, mCTh, and pCTh (P ≤ .042). Alternate CTh was also significantly lower in the COD group (P = .005). There was a significant correlation between inferior and alternate CTh measurements (r = 0.636, P < .001). No significant differences were observed in cortical or trabecular FD between groups (P ≥ .072). CONCLUSIONS: Female patients with COD had significantly lower inferior and alternate CTh than healthy controls. Both groups had similar cortical and trabecular bone textures.

Radioanatomic study of maxillary sinus palatal process pneumatization.

OBJECTIVES: To perform a detailed analysis of palatal process pneumatization (PPP) on cone beam computed tomography (CBCT) images. METHODS: This study consisted of 376 maxillary sinuses of 188 patients aged 22-88 years who had maxillary CBCT scans. The radioanatomy of the PPP was evaluated at distances 4, 8, 16, and 24 mm posterior to incisive foramen. The types of PPP were classified as follows: type I: maxillary sinus palatal process non-gasified; type II: palatal process gasification into the nasal floor, but not more than half of the width of the nasal floor; and type III: palatal process gasification into the nasal floor more than half of the width of nasal floor. Sinus opening angle (SOA), palatonasal recess angle (PNRA), palatal junction angle (PJA), and palatal depth measurement (PDM) were the evaluated parameters. RESULTS: Among the identified 1315 PPPs, type I PPP (880, 66.92%) was the most frequently observed, followed by type II (426, 32.4%), and the least observed was type III PPP (9, 0.68%). There was no significant difference between SOA and PJA according to the types of PPP (p > 0.05). The difference between PNRA and PDM of type I and type II PPP showed a statistically significant difference (p < 0.05). Type I PPP was the most encountered with the highest PDM, and PNRA was narrower in type III than in type II PPP. CONCLUSION: Physicians must be aware of these variations to prevent possible complications during surgery because 33.08% of the maxillary sinuses showed extensive pneumatization through the palatal process.

Association between root taper and root proximity of single-rooted teeth with periodontitis: a cone-beam computed tomography based study.

This study aimed to determine the association between the root taper and proximity of single-rooted teeth with periodontitis using cone-beam computed tomography (CBCT). CBCT images of 362 single-rooted teeth from 37 patients were evaluated. This case-control study analyzed 17 participants with stage II and III periodontitis, (n = 161 teeth, periodontitis group) and 20 participants with healthy periodontium (n = 201 teeth, control group). Multiplanar reconstructions were used for proximity measurements, and cross-sectional images for calculating the angle of the root tapers. Root proximity, root length, and root taper were measured. Multivariate binary logistic regression analysis was used to determine association with periodontitis. In the periodontitis group, the upper lateral root-taper was 18.33° ± 3.25° and was significantly higher when compared to the control group (p = 0.001). The root taper of the lateral incisor was associated with the diagnosis of periodontitis (p = 0.01) with an odds ratio of 1.541 according to regression analysis. Root length was also identified as a potential protective parameter. The risk of being diagnosed with periodontitis decreases when root length increases by 0.785 times (p = 0.043). Upper canines in the periodontitis group presented shorter root lengths (p = 0.039) and higher root tapers (p = 0.01). Also, mandibular canines were closer form adjacent teeth in the periodontitis group (p = 0.042). This study indicated that short-root and increased root-taper at specific teeth could be considered as risk indicators for periodontitis.

Radiologic prognosis of an idiopathic bone cavity of the mandible in 1-year period

An idiopathic bone cavity (IBC) tends to rise as an abnormality in osseous growth, a degenerating tumoral process, or triggered by hemorrhagic trauma. This paper describes the interpretation of an IBC and its progression over one year. The patient's initial radiographic images showed well-defined multilocular radiolucency located at the right mandibular molar region, extending between the teeth and the mandibular basis. No clinical symptoms were present, and the course of the mandibular canal was not altered. The lesion was not initially biopsied due to the patient's dental anxiety. Over one year, the radiolucent area extended anteriorly and thinned the lingual and buccal cortices. Prior radiolucent areas changed to granular-appearing bone. The diagnosis was based on a fine-needle aspiration biopsy. The appearance of an IBC is not unique; its benign nature should be differentiated from multilocular or fibro-osseous lesions by a careful interpretation of clinical and radiological perspectives.

Is there any predictive bone parameter for implant stability in 2-dimensional and 3-dimensional radiologic images?

OBJECTIVES: This ex vivo study aimed to compare radiomorphometric parameters between 2-dimensional (2-D) and 3-dimensional (3-D) radiographs and evaluate the influence of preoperative radiologic bone parameters on the clinical outcomes of implant stability. STUDY DESIGN: Implant recipient sites in fresh bovine blocks were evaluated on panoramic radiographs for gray value (GV), fractal dimension (FD), number of connected trabeculae (Co), and density of connected trabeculae (CoD). Cone beam computed tomography (CBCT) scans were evaluated for trabecular thickness (TbTh), cortical thickness (CTh), degree of anisotropy (DA), FD, and Co. Insertion torque (IT) and implant stability quotient (ISQ) were measured. RESULTS: GV was significantly correlated with all parameters in 2-D and 3-D images except FD in 2-D and Co in 3-D, and with all surgical parameters (P ≤ .029). Co and CoD values on panoramic radiographs had significant correlation with TbTh, CTh, and DA values on CBCT images (P < .001). All 2-D parameters and TbTh and CTh in the CBCT data were significantly correlated with IT only (P ≤ .047). Only GV was correlated with ISQ measurements (P ≤ .029). CONCLUSIONS: GV, Co, and CoD values on panoramic radiographs reflect the architecture of trabecular bone and the thickness of cortical bone, and might help predict implant stability in clinical situations.

Assessment of the trabecular structure of mandibular condyles in patients with temporomandibular disorders using fractal analysis.

OBJECTIVES: The aim of this study was to evaluate changes in the trabecular structure of the mandibular condyle in patients with temporomandibular disorders (TMDs) using fractal analysis. STUDY DESIGN: A total of 100 patients ages 18 to 73 years were clinically assessed using the Diagnostic Criteria for Temporomandibular Disorders. The control group was age- and sex-matched with the patient group. Panoramic radiographs were obtained using a Kodak 8000 digital device with 73 kVp and 5 mA fixed parameters. The degree of degeneration in the mandibular condyles was calculated. Regions of interest (84 × 84 pixels) were selected within the cortical boundary of the mandibular condyle, and the fractal dimension (FD) was calculated using ImageJ version 1.48. RESULTS: Radiographic degenerative changes were more frequently present and more severe in the patient group (P < .001). The mean value of FD was 1.22 ± 0.06 in the patient group and 1.25 ± 0.06 in the control group (P = .001). A significant decrease in FD was observed (P = .001) in the left temporomandibular joints of the patient group, whereas a nonsignificant decrease in FD was observed in the right temporomandibular joints (P = .073) as degenerative changes increased. CONCLUSIONS: Lower FD values were associated with more severe degenerative changes in the patient group. The trabecular structure of condyles in patients with TMD exhibited decreased complexity when erosive and sclerotic changes were evident. As a result, fractal analysis enhanced the use of panoramic radiography in detecting degenerative changes in patients with TMD.