Diagnostic capabilities of fractal dimension and mandibular cortical width to identify men and women with decreased bone mineral density

Evaluation of mandibular bone structure changes in patients with phenylketonuria through fractal analysis and radiomorphometric indices

OBJECTIVES

The aim of this study was to evaluate the effect of phenylketonuria (PKU) on mandibular bone structure by comparing the bone of PKU patients with healthy controls using fractal analysis (FA) and the radiomorphometric indices of mandibular cortical width (MCW) and mandibular cortical index (MCI).

STUDY DESIGN

In total, 32 patients with PKU were analyzed and compared with the control participants. Regions of interest in panoramic radiographs were selected and the fractal dimension (FD) obtained from FA was calculated. MCW was defined as the cortical thickness of the inferior border of the mandible at the level of the mental foramen. MCI classified the endosteal edge of the mandibular cortex as C1: straight and sharp, C2: the presence lacunar resorption spaces, and C3: distinctly porous and severely eroded. The significance level was P < .05.

RESULTS

All FD and MCW values were significantly lower in the PKU patients. The prevalence of C1 was significantly lower and prevalence of C2 was significantly higher in the PKU group.

CONCLUSIONS

The differences in FD and radiomorphometric indices between patients with PKU and healthy controls may indicate a potential impact of PKU on mandibular bone structure.

Comparison of quantitative radiomorphometric predictors of healthy and MRONJ-affected bone using panoramic radiography and cone-beam CT

OBJECTIVES

To determine the most distinctive quantitative radiomorphometric parameter(s) for the detection of MRONJ-affected bone changes in panoramic radiography (PR) and cone-beam CT (CBCT).

METHODS

PR and sagittal CBCT slices of 24 MRONJ patients and 22 healthy controls were used for the measurements of mandibular cortical thickness (MCT), fractal dimension (FD), lacunarity, mean gray value (MGV), bone area fraction (BA/TA), trabecular thickness (Tb.Th), trabecular separation (Tb.Sp), trabecular number (Tb.N). MCT was measured in the mental foramen region. While FD and lacunarity were measured on mandibular trabecular and cortical regions-of-interest (ROIs), the remaining parameters were measured on trabecular ROIs. The independent samples t-test was used to compare the measurements between the MRONJ and control groups for both imaging modalities (P = .05).

RESULTS

MCT was the only parameter that differentiated MRONJ-affected bone in both PR and CBCT (P < .05). None of the remaining parameters revealed any difference for MRONJ-affected bone in CBCT (P > .05). FD, lacunarity, MGV, BA/TA, and Tb.Sp could distinguish MRONJ-affected trabecular bone in PR (P < .05). The correspondent ROI for both imaging methods that was reliable for detecting MRONJ-affected bone was the trabecular bone distal to the mental foramen above the inferior alveolar canal (ROI-3).

CONCLUSIONS

MCT is a reliable parameter for the discrimination of MRONJ-affected bone in both PR and CBCT images. PR may be used to detect MRONJ-affected trabecular bone using FD, lacunarity, MGV, BA/TA, and Tb.Sp measurements as well.

Efficacy of the CALM® Algorithm in Reducing Motion-Induced Artifacts in CBCT Imaging: A Fractal Dimension Analysis of Trabecular Bone

OBJECTIVE

The primary goal of this investigation was to ascertain the efficacy of the CALM® motion artifact reduction algorithm in diminishing motion-induced blurriness in Cone Beam Computed Tomography [CBCT] images. The assessment was conducted through Fractal Dimension [FD] analysis of the trabecular bone.

METHODS AND MATERIALS

A desiccated human mandible was subjected to Planmeca ProMax 3D® scanning under eight distinct protocols, marked by variations in motion presence [at 5, 10, and 15 degrees] and the deployment of CALM®. In every scan, five distinct regions of interest [ROIs] were designated for FD analysis, meticulously avoiding tooth roots or cortical bone. The FD was computed employing the box-counting method with Image-J 1.53 software.

RESULTS

Our findings reveal that a 5-degree motion does not significantly disrupt FD analysis, while a 10-degree motion and beyond exhibit statistical differences and volatility among the sites and groups. A decreased FD value, signifying a less intricate or "rough" bone structure, correlated with amplified motion blurriness. The utilization of CALM® software seemed to counteract this effect in some instances, reconciling FD values to those akin to the control groups. Nonetheless, CALM®'s efficacy differed across sites and motion degrees. Interestingly, at one site, CALM® application in the absence of motion resulted in FD values considerably higher than all other groups.

CONCLUSION

The study indicates that motion, particularly at 10 degrees or more, can considerably impact the FD analysis of trabecular bone in CBCT images. In some situations, the CALM® motion artifact reduction algorithm can alleviate this impact, though its effectiveness fluctuates depending on the site and degree of motion. This underscores the necessity of factoring in motion and the employment of artifact reduction algorithms during the interpretation of FD analysis outcomes in CBCT imaging. More research is necessary to refine the application of such algorithms and to comprehend their influence on different sites under varying motion degrees.

Fractal Dimension and Lacunarity Analysis in the Dentulous and Edentulous Mandibular Posterior Region Using Cone-beam Computed Tomography: A Cross-sectional Retrospective Study

AIMS

This cross-sectional retrospective study was conducted to assess the differences in the microarchitecture of the trabecular bone of the posterior mandibular region at dentulous and edentulous sites with the help of fractal dimension (FD) and lacunarity using cone-beam computed tomography (CBCT).

MATERIALS AND METHODS

Ninety CBCT scans were analyzed for the purpose of the present study. Inclusion criteria included subjects with unilaterally missing mandibular molars or premolars and an with intact contralateral opposing tooth. The coronal view of the dentulous and edentulous sites was used, and the region of interest (ROI) was selected 2.6 mm below the apex of the tooth present. These images were then transferred to ImageJ Software, and fractal analysis was done using the box-counting method of the FracLac plug-in. A paired samples t-test was performed to compare the means of FD and lacunarity, and a Kendall correlation was performed to check correlations. A p-value less than 0.05 was considered to indicate statistical significance.

RESULTS

Statistical analysis revealed that the mean FD of the edentulous side was significantly greater than that of the dentulous side (p-value = 0.011). Additionally, the mean lacunarity of the edentulous side was marginally significantly greater than that of the dentulous side (p-value = 0.089). A significant negative correlation was detected between the FD and lacunarity of the edentulous region (p-value = 0.017), and a marginally significant negative correlation was detected between edentulous lacunarity and dentulous lacunarity (p-value = 0.081).

CONCLUSION

The differences in occlusal forces exerted in dentulous and edentulous regions can lead to a change in the trabecular pattern of the bone in these regions. This change in the microarchitecture of bones can be detected by FD and lacunarity, which can further help us assess changes pre- and post-implant.

CLINICAL SIGNIFICANCE

The advanced technology, the assessment of microarchitecture of the bone has been made easy, using FD and lacunarity, as done in the present study. This analysis can further aid us in both pre- and post-implant analysis to prevent failure of the implant. How to cite this article: Bhoraskar M, Denny C, Srikant N, et al. Fractal Dimension and Lacunarity Analysis in the Dentulous and Edentulous Mandibular Posterior Region Using Cone-beam Computed Tomography: A Cross-sectional Retrospective Study. J Contemp Dent Pract 2024;25(6):581-587.

Radiomorphometric indices of the mandible as indicators of decreased bone mineral density and osteoporosis - meta-analysis and systematic review

This review aims to evaluate the accuracy of various mandibular radiomorphometric indices in comparison with DEXA BMD measurements in the diagnosis of osteopenia and osteoporosis based on a meta-analysis of the sensitivity and specificity of the indices. PRISMA statement was followed. The materials for analysis were collected in August 2023 by searching three databases: PubMed Central, Web of Science, and Scopus. The selection of studies consisted of three selection stages, and 64 articles were finally obtained. Quality assessment was performed with the QUADAS-2 tool, and the general methodological quality of retrieved studies was low. Statistical analysis was performed based on 2 × 2 tables and estimated sensitivity and specificity were obtained using SROC curves. The most used indices were MCI, MCW and PMI. The best results in detecting reduced BMD obtained for MCW ≤ 3 mm, estimated sensitivity and specificity were 0.712 (95% CI, 0.477-0.870) and 0.804 (95% CI, 0.589-0.921), respectively. The most prone to the risk of bias is the MCI due to the examiner's subjectivism. Radiomorphometric indices of the mandible can be useful as a screening tool to identify patients with low BMD, but should not be used as a diagnostic method. Further research needs to focus on analysing the ability of the indices to detect osteoporosis and also in combination the indices with clinical parameters.

Evaluation of Jaw Bone Change in Children and Adolescents with Rheumatic Heart Disease by Fractal Analysis

BACKGROUND

Recognizing the oral needs of people living with rheumatic heart disease (RHD), particularly in relation to their jaws, is of paramount importance.

AIMS

This study aimed to evaluate potential jaw bone changes in children and adolescents diagnosed with RHD and compare them with a group of healthy children and adolescents.

METHODS AND MATERIAL

The dental panoramic radiographs (DPRs) of 32 children and adolescents diagnosed with RHD comprised the case group. In contrast, the control group consisted of DPRs from 32 children and adolescents without any known diseases. Two regions of interest (ROI1 and ROI2) of trabecular bone and a separate region of interest (ROI3) of cortical bone were selected for fractal analysis. The mandibular cortical index (MCI) was evaluated.

RESULTS

The ROI1 fractal dimension (FD) value of the individuals in the case group was statistically higher in the right jaw than in the left jaw (P < 0.01). Significant differences were determined between the case and control groups regarding the left ROI1, and the left and the right ROI2 (P < 0.05). No significant difference was found between the patient and control groups regarding the MCI value (P > 0.05).

CONCLUSIONS

The results of this study showed that bone metabolism was affected unilaterally in the condyle region and bilaterally in the gonial region of patients with RHD. It also revealed that the cortical layer was not affected.

Evaluation of Bone Mineral Changes in Panoramic Radiographs of Hypothyroid and Hyperthyroid Patients Using Fractal Dimension Analysis

Objective Hyperthyroidism and hypothyroidism are endocrinopathies that cause a decrease in bone mineral density. The aim of this study is to investigate possible bone changes in the mandible caused by hyperthyroidism and hypothyroidism using fractal analysis (FA) on panoramic radiographs. Material and Methods Panoramic radiographs of a total of 180 patients, including 120 patient groups (60 hyperthyroid, 60 hypothyroid) and 60 healthy control groups, were used. Five regions of interests (ROI) were determined from panoramic radiographs and FA was performed. ROI1: geometric midpoint of mandibular notch and mandibular foramen, ROI2: geometric midpoint of mandibular angle, ROI3: anterior of mental foramen, ROI4: basal cortical area from distal mental foramen to distal root of first molar, ROI5: geometric center of mandibular foramen and mandibular ramus. Results While a significant difference was observed between the patient and control groups regarding ROI1 and ROI2 (p < 0.05); there was no significant difference between the groups in relation to ROI3, ROI4, and ROI5. All FA values were lower in the hyperthyroid group than in the hypothyroid group. Conclusion Fractal analysis proves to be an effective method for early detection of bone mass changes. In the present study, it was concluded that while the mandibular cortical bone was intact, trabecular rich regions were affected by osteoporosis caused by thyroid hormones. Necessary precautions should be taken against the risk of osteoporosis in patients with thyroid hormone disorders.

Fractal characteristics of the trabecular pattern of the mandible in patients with renal transplantation

OBJECTIVE

In this study, we examined the mandibular trabecular bone structures by performing fractal dimension (FD) analysis in patients who underwent renal transplantation (RTx).

METHODS

Our study is an observational study with 69 RTx patients and 35 control group patients. The mean FD values of the patient and control groups were calculated and compared. In addition, biochemical parathyroid hormone (PTH), serum calcium, phosphorus, alkaline phosphatase (ALP), and vitamin-D parameters and FD values of both groups were analyzed.

RESULTS

FD values were significantly lower in the patient group than in the healthy group (p < .05). In the RTx group compared to the control group, ALP (90.71 ± 34.25-66.54 ± 16.8, respectively) (p < .001) and PTH (75.76 ± 38.01-38.17 ± 12.39, respectively) (p < .001) values were higher. There was a positive correlation between the FD values and ALP (rspearman  = .305, p = .011) and a negative correlation between FD values and vitamin-D (rspearman  = .287, p = .017) of patients with RTx.

CONCLUSION

FD values were found to be lower in patients who underwent RTx compared to the control group. It should be considered that FD analysis can be a method that can be used to evaluate trabecular bone structure in patients undergoing RTx.

Pilot study of fractal dimension analysis of osteogenesis for bone substitute materials of Bio-Oss in lateral sinus augmentation

BACKGROUND

Fractal dimension (FD) analysis has been proposed and validated in osseointegration-related research. The aim of this study was to evaluate the feasibility of FD analysis in the osteogenesis detection of bone substitute materials (BSMs) of Bio-Oss in maxillary lateral sinus augmentation.

METHODS

Patients who received lateral maxillary sinus augmentation and underwent grafting with BSMs (Bio-Oss) were included in the study. The cross sections of the BSMs under cone-beam computed tomography (CBCT) at mesial, distal, and sagittal directions were obtained immediately after the graft (T0) and 6 months later (T1), and the obtained images were cropped to include only the BSMs. The FD analysis was performed, and the FD value was obtained by the method of box-counting. Paired t-tests and analysis of variance (ANOVA) were used, and p-values <0.05 was considered statistically significant.

RESULTS

Twelve participants with 22 implants, which were inserted simultaneously after sinus augmentation, were included in this study. A total of 22 mesial, 22 distal, and 14 sagittal images were obtained after FD analysis. The mean FD value and standard deviation at T0 was 1.2860 ± 0.0896, while at T1, it was 1.2508±0.1023; thus, significant differences were detected (p = 0.022). However, the increasing or decreasing trend of FD value was not stable, and no significant difference was detected for FD values of mesial, distal, and sagittal images between T0 and T1. ANOVA indicated that no significant difference was detected among the FD values of mesial, distal, and sagittal images at any timepoint. Differences in FD values between the sexes were not significant either.

CONCLUSIONS

Since the FD analysis for the osteogenesis detection of BSMs in maxillary sinus augmentation indicated unstable trends of change, its feasibility is not reliable. The initially rough surface, self-degradation, and volume change of the BSMs during osteogenesis may be the reason for the variation in FD values.

Evaluation of cortical and trabecular bone structure of the mandible in patients using L-Thyroxine

BACKGROUND

Long-term use of L-Thyroxine (LT4), the synthetic thyroxine hormone used for thyroid hormone replacement therapy, is an important risk factor for osteoporosis. The aim of this study was to investigate the differences between mandibular cortical index (MCI) and trabecular bone fractal dimension (FD) values on panoramic radiographs of patients using LT4 and control subjects.

METHODS

A total of 142 female patients, 71 cases and 71 controls, were analyzed in the study. Ages were matched in case and control groups and the mean age was 36.6 ± 8.2 (18 to 50) years. MCI consisting of C1 (Normal Mandibular Cortex), C2 (Moderately Resorbed Mandibular Cortex) and, C3 (Severely Resorbed Cortex) scores was determined for case and control groups. Fractal analysis was performed using ImageJ on selected regions of interest from the gonial and interdental regions. The box-count method was used to calculate FD values. Wilcoxon signed-rank test, Mann-Whitney U test, and Spearman correlation analysis were applied to compare the measurements. Statistical significance of differences was established at P < 0.05 level.

RESULTS

FD values did not show statistically significant differences between case and control groups (p > 0.05). The mean FD in the right gonial region was 1.38 ± 0.07 in the case group and 1.38 ± 0.08 in the control group (p = 0.715). The mean FD in the right interdental region was 1.37 ± 0.06 in the cases and 1.36 ± 0.06 in the control group (p = 0.373). The mean FD in the left gonial region was 1.39 ± 0.07 in the cases and 1.39 ± 0.07 in the control group (p = 0.865). The mean FD in the left interdental region is 1.37 ± 0.06 in the cases and 1.38 ± 0.05 in the control group (p = 0.369). The most common MCI score was C1, with 62% in the cases and 83.1% in the control group. MCI scores showed a statistically significant difference between cases and controls (p = 0.016, p < 0.05). While the C2 score was higher in the cases, the C1 score was higher in the controls.

CONCLUSIONS

LT4 use was not associated with the FD of mandibular trabecular bone, but was associated with MCI values of cortical bone. Further studies on larger samples with different imaging modalities and image processing methods are needed.

Evaluation of cortical and trabecular bone structure of the mandible in patients with ankylosing spondylitis

This study aimed to examine the difference between the fractal dimension (FD) values of the mandibular trabecular bone and the panoramic mandibular index (PMI), mandibular cortical index (MCI) and mandibular cortical thickness (MCW) of patients with ankylosing spondylitis (AS) and healthy control group. A total of 184 individuals (92 cases, 92 controls), were examined in our study. PMI, MCI, and MCW values were calculated on panoramic images of all individuals. For FD values, the region of interest (ROI) was selected with the size of 100 × 100 pixels from the right-left gonial and interdental regions and 50 × 50 pixels from the condylar region. Degenerative changes in the temporomandibular joint (TMJ) region were recorded. PMI, MCI, and MCW values showed statistically significant differences between the groups (p = 0.000, p < 0.001). The radiological signs of mandibular cortical resorption were more severe in the case group than in the control group. PMI and MCW values were found to be lower in the case group than in the control group. It was determined that the number of C3 and C2 values, among the MCI values, was higher in the case group. Only the FD values of the ROI selected from the condyle region were found to be statistically significant and were lower in the case group (p = 0.026, p < 0.05). Degenerative changes in the TMJ region were significantly more frequent in the case groups (p = 0.000, p < 0.001). The fact that the mandibular cortex shows more resorptive features in individuals with AS may require further evaluation in terms of osteoporosis. Because of the low FD values of the condylar regions of these patients and the more frequent degenerative changes, the TMJ region should be followed carefully. Detailed examination of the mandibular cortex and condylar region is beneficial in patients with AS for screening and following osteoporotic changes in these individuals, which is essential for the patient's life quality.

Is there a correlation between radiographic absorptiometry of the phalanges of the hand and radiomorphometric indices of the mandible?

OBJECTIVES

The aim of this study was to correlate the mandibular bone quality through radiomorphometric indices in panoramic radiograph with bone quality of non-dominant hand phalanges by radiographic absorptiometry phalanx (RA).

METHODS

The sample consisted of 167 patients (128 women and 39 men) with a mean age of 52.09 (± 11.5) divided into four groups according to RA test: (A) 92; (B) 36; (C) 25 and (D) with 14.9. A panoramic radiograph was taken of each patient and one observer made measurements of cortical thickness at the mental foramen (mental index, MI) and gonion (goniac index, GI) regions and fractal dimension (FD) analyze in mandibular ramus. In phalangeal radiograph was made measurements of cortical thickness at the intermediate (medial phalange index, MPI) and proximal (proximal phalange index, PPI) phalangeal.

RESULTS

The results showed correlation (p < 0.00037) between Klemetti index with RA. Variance analysis MI, GI, MPI, PPI shown significant differences (p < 0.05) between the two groups (normal and low bone mineral density - BMD). Area under the ROC curve was 0.74 (sensitivity = 97.4%, specificity = 78%) for MI, 0.79 (sensitivity = 94, specificity = 54%) for GI, 0.77 (sensitivity = 94.8%, specificity = 64%) for MPI, 0.76 (sensitivity = 93.1%, specificity = 62%) for PPI, 0.71 (sensitivity = 96.5%, specificity = 86%) for FD.

CONCLUSIONS

Our results suggest that the analysis of radiomorphometric indices showed moderate accuracy for detecting changes in mandibular bone quality according to AR.

Investigation of the effect of oral and internal bisphosphonate use on bone density in the jaws in patients with osteoporosis in panoramic radiography

OBJECTIVES

This study aims to quantitatively evaluate the effects of bisphosphonate use duration and route of administration on mandibular cortical and trabecular bone in postmenopausal women.

STUDY DESIGN

Ninety postmenopausal women over the age of 50 were included in this study. Trabecular bone density was specified numerically by fractal dimension (FD) in the region of interest selected on the panoramic radiograph. The width of the mandibular cortical (MCW) bone under the mental foramen of the mandible was measured. Mann-Whitney U test was used for parameters that did not show a normal distribution. Spearman rho correlation test was used to determine the relationship between continuous measurement parameters.

RESULTS

It was observed that FD and MCW of dentate and edentate individuals using bisphosphonate were statistically significantly lower than those of healthy individuals (P < .05). There was no significant correlation was found between the duration of use of bisphosphonates and the fractal values obtained from the relevant regions of the mandible (P > .05).

CONCLUSION

Fractal dimension was found to be lower in oral bisphosphonate use than in intravenous bisphosphonate use. The width of the mandibular cortical bone values was found to be lower in individuals using bisphosphonate than in healthy individuals. Fractal dimension and MCW may benefit clinicians as quantitative parameters in panoramic radiography in the diagnosis of osteoporosis.

Radiomorphometric indices and fractal dimension of the mandible in individuals with osteogenesis imperfecta: a matched cross-sectional study

OBJECTIVE

The objective was to analyze radiomorphometric indices (RMIs) of mandibular cortical bone and fractal dimension (FD) of trabecular bone of individuals with osteogenesis imperfecta (OI) and compare the findings to those of individuals without OI.

METHODS

Digital panoramic radiographs of 20 individuals with OI (case group) and 40 individuals without OI (control group) were examined. The RMIs of mandibular cortical index (MCI) and mandibular cortical thickness (MCT) were analyzed. FD of mandibular trabecular bone was calculated bilaterally in 3 regions. The chi-squared test and paired t test were used to compare the significance of differences between the groups. The effect size and minimal clinically important difference (MCID) were also determined. Significance was established at P < .05.

RESULTS

Categories C2 and C3 of the MCI were more frequent in individuals with OI (P < .001). The Mean MCT was 2.08 ± 0.79 in the OI case group and 2.91 ± 0.60 in the control group (P < .001). Mean FD in the condylar region was significantly lower in the OI case group (P = .002). The effect size for these 2 measures was large, and the difference between groups was greater than the MCID.

CONCLUSION

Radiographs of individuals with OI exhibited more porosity and diminished thickness of the mandibular cortical bone and lower FD values in the condylar trabecular bone.

Fractal dimension, lacunarity, and cortical thickness in the mandible: Analyzing differences between healthy men and women with cone-beam computed tomography

Purpose

The objective of this study was to assess the fractal dimension, lacunarity, trabecular microarchitecture parameters, and cortical linear measurements in the mandibles of male and female individuals to identify differences between them.

Materials and Methods

In total, 116 cone-beam computed tomography scans of healthy individuals of different ages (57 men and 59 women, aged between 20 and 60 years) were selected. The following bone parameters were measured: 1) buccal, lingual, and basal cortical bone thickness in 5 standard parasagittal sections (the midline, the left and right sides of the lower lateral incisors, and the left and right sides of the lower canines); 2) the bone volume fraction of 10 sequential axial sections from each patient by creating a volume of interest in the area between the lower canines; and 3) fractal dimension and lacunarity using grayscale images of the same region of the volume of interest in the anterior mandible. Spearman correlation coefficients and the Mann-Whitney test were used.

Results

A significant and positive correlation was found between age and cortical thickness, especially in the region of the central incisors. Significant differences between sexes in terms of fractal dimension, lacunarity, and bone volume were found. Women revealed lower fractal dimension values and higher lacunarity and bone volume ratio values than men.

Conclusion

Fractal dimension, lacunarity, trabecular bone volume, and cortical thickness were different between men and women of different ages.

Osteoporosis Screening Using Dental Panoramic Radiographs and Age at Menarche

Since early detection of osteoporosis is essential, the development of an efficient and cost-effective screening model would be incredibly beneficial. The aim of this study was to evaluate the diagnostic accuracy of MCW and MCI indices from dental panoramic radiographs in combination with a new variable, age at menarche, for the detection of osteoporosis. The study enrolled 150 Caucasian women (aged 45 to 86) who met the eligibility criteria, had DXA scans of the left hip and lumbar spine (L2 to L4), and were classified as osteoporotic, osteopenic, or normal based on T-score. Two observers evaluated MCW and MCI indexes on panoramic radiographs. There was a statistically significant correlation between the T-score and MCI and MCW. In addition, age at menarche had a statistically significant correlation with T-score (p = 0.006). In conclusion, in the current study, MCW proved to be more effective in detecting osteoporosis when combined with age at menarche. Individuals with MCW less than 3.0 mm and age at menarche later than 14 years old should be referred for DXA since they present high risk of osteoporosis.

Comparative evaluation of trabecular bone structures of bruxist and non-bruxist individuals with bone apposition in the mandible angle region by fractal analysis

OBJECTIVE

This study aimed to compare the trabecular internal structure of different regions of the mandible according to the grades of appositional classification in the mandible angle region in probable bruxist individuals and non-bruxist G0(Convex course of the basal cortex, no directional change, no bone apposition) individuals by measuring fractal dimension (FD) on panoramic radiographs.

METHODS

200 sample jaws, bilaterally, of 80 probable bruxists and 20 non-bruxist G0 individuals were included in the study. According to the classification in the literature, each mandible angle apposition severity was classified as G0-G1-G2-G3. FD was calculated by selecting the region of interest (ROI) area of 7 regions from each sample. Gender differences in changes between ROIs in radiographs and independent samples t-test were evaluated. Relation between categorical variables was determined by chi-square test (p < .05).

RESULTS

In the comparison of the probable bruxist and non-bruxist G0 groups, FD was found to be statistically significantly higher in the mandible angle (p = 0.013) and cortical bone (p = 0.000) regions in the probable bruxist group than in the non-bruxist G0 group. There is a statistically significant difference between probable bruxist G0 and non-bruxist G0 grades in terms of FD averages in cortical bone (p < 0.001). A statistically significant difference was found in the relationship of ROIs with gender in canine apex (p = 0.021) and canine distal (p = 0.041) regions.

CONCLUSION

FD was found to be higher in the mandibular angle region and cortical bone in probable bruxist individuals than in non-bruxist G0 individuals. Morphological changes seen in the mandible angulus region may be a finding that may raise suspicion for bruxism for clinicians.

Evaluation of the effect of antiepileptic drugs on mandibular bone quality by fractal analysis

OBJECTIVES

Antiepileptic drugs (AEDs) are used to control seizures in epilepsy and their long-term use is common. AED use has been associated with decreased bone mineral density. The aim of this study is to determine the effect of AEDs on mandibular bone quality using fractal analysis and panoramic morphometric indices.

METHODS

In this study, dental and medical records of 132 patients (66 AED users and 66 control group) were used. Fractal analysis (FA), the panoramic mandibular index (PMI), mandibular cortical width (MCW), and Klemetti index (KI) measurements were performed on panoramic radiographs.

RESULTS

In all metrics, the mean values of the study group were significantly lower than the control group (p < 0.000). There is a statistically significant difference between the study and control groups in terms of KI distribution (p < 0.000). The mean fractal dimension (FD) values in each measured region of the female patients in the study group were found to be significantly lower than the female patients in the control group (p < 0.05). The mean FD values measured in ROI-2 and ROI-3 of male patients in the study group were found to be significantly lower than male patients in the control group (p < 0.05).

CONCLUSION

The side effects of AEDs on bone metabolism were shown in this study. Dentists examining patients with epilepsy should be careful about osteoporotic changes in the jaws.

The effects of vitamin D deficiency on mandibular bone structure: a retrospective radiological study

OBJECTIVE

The aim of the study was to evaluate the effects of vitamin D deficiency on the mandibular bone structure by fractal analysis and panoramic morphometric indices.

METHODS

Ninety participants were divided into three groups as 30 individuals with severe vitamin D deficiency, 30 individuals with vitamin D deficiency, and 30 individuals with vitamin D sufficiency. Fractal dimension analysis (FD), panoramic mandibular index (PMI), mandibular cortical index (MCI), and mandibular cortical thickness measurement (CTM) were evaluated on panoramic radiographs.

RESULTS

FD values of the patients with vitamin D deficiency were found to be statistically lower than the patients with vitamin D sufficiency (p < 0.05). FD value of supracortical area above the angulus mandible (FD2) in patients with severe vitamin D deficiency was significantly lower than FD values (p = 0.002). There was no statistically significant difference between the groups in the CTM (p > 0.05). PMI was significantly lower in patients with severe vitamin D deficiency (p < 0.001). There was a significant difference in MCI values between the groups (p < 0.05).

CONCLUSION

Vitamin D deficiency causes a decrease in bone mineral density in the mandible, and an increase in alveolar porosity. FD analysis and radiomorphometric indices in panoramic radiographs can be used to assess osteoporotic changes in patients with vitamin D deficiency.

Evaluation of temporomandibular joint components and mandibular bone structure in ankylosing spondylitis patients

OBJECTIVES

The study aimed to investigate the mandible and temporomandibular joint (TMJ) in patients with ankylosing spondylitis (AS) who had no signs or symptoms of TMJ-related disease and compare them with a control group.

STUDY DESIGN

In total, 128 panoramic radiographs (63 patients with AS, 65 controls) were evaluated. Fractal analysis was conducted on the mandibular condyle (ROI1), angle of the mandible (ROI2), and the area adjacent to the mental foramen (ROI3). Articular eminence inclination (AEI) values were measured. Klemetti index (KI) evaluation of the mandibular cortex was also performed.

RESULTS

Fractal dimension (FD) values were significantly lower in the patients with AS than the controls in ROI1 and ROI2 (P = .001), but there were no significant differences between groups for FD in ROI3, AEI, or KI (P ≥ .09). No significant differences were found in any parameters between patients with AS with different disease durations (P ≥ .06).

CONCLUSIONS

Patients with AS displayed significantly lower FD values in condyles and the angle of the mandible and slightly lower AEI values; therefore, they should be examined routinely for TMJ disorders. Clinicians should be aware of the possibility of secondary osteoporosis in patients with AS and consider its probable effects on the mandible.

Fractal Dimension and Radiomorphometric analysis of Orthopanoramic radiographs in patients with tobacco and areca nut associated oral mucosal lesions: A pilot in-vivo study in a North Indian cohort

OBJECTIVE

The aim of this study was to determine the fractal dimension (FD) and radiomorphometric indices (RMIs) in the mandible from orthopantomographic radiographs in patients with oral lesions associated with smokeless/smoking tobacco (SLT/ST) and areca nut habits in a North Indian cohort.

STUDY DESIGN

A prospective, cross-sectional, observational pilot study was conducted of 120 subjects, including controls and 3 study groups of 30 patients each with oral submucous fibrosis, tobacco pouch keratosis, and oral leukoplakia (OL). Two observers calculated FD and the RMIs of mandibular cortical thickness (MCT), panoramic mandibular index (PMI), and mandibular cortical index (MCI).

RESULTS

Mean FD was significantly reduced compared to controls with all oral lesions (P < .05) and with all habits in 3 of 4 regions of interest (P < .05). MCT was significantly reduced with OL (P < .005) and in ST users (P < .05). PMI did not differ regarding lesion status or habits. Compared to the controls, MCI C2 type was significantly more common in all oral lesions (P ≤ .005) and all types of habit (P < .005). Inter- and intraobserver agreement was strong to excellent.

CONCLUSIONS

FD and RMI values were significantly altered compared to controls in oral lesions associated with tobacco and areca nut habits and in the dominant type of habit.

Does Fractal Analysis Have a Role in Diagnosis of Langerhans Cell Histiocytosis?

PURPOSE

Langerhans cell histiocytosis (LCH) of the jaws is a rare disease and is often diagnosed at an advanced stage. This study aims to assess the trabecular pattern of jaws via fractal analysis (FA) on initial panoramic radiographs (OPG) of the patients with LCH to facilitate interpretation of the radiographic changes.

METHODS

A case-control study investigated LCH cases with jaw involvement retrieved from the databases of Istanbul and Kocaeli Universities between 2010 and 2021. Initial OPGs of LCH cases and OPGs of healthy sex- and age-matched controls were investigated with FA. All images were assessed using ImageJ software. On each OPG, a total of 6 regions of interest (ROIs) located on the mandible were investigated bilaterally. The independent variables were the trabecular patterns of jaws of LCH cases and their control matches. The outcome variables were the fractal dimension (FD) values obtained from the ROIs on OPGs. Data were analyzed using the Mann-Whitney U test and Student's t test.

RESULTS

Fifteen LCH-control pairs were investigated. In one ROI located in the supracortical area above the left mandibular angle, FD values of LCH cases (1.273 ± 112.8) were significantly lower than controls (1.308 ± 85.3; P < .05). Lower FD values were also calculated for some of the remaining ROIs, but there was no significant difference between groups (P > .05).

CONCLUSIONS

Regarding our results, FA was not a useful parameter to discern radiographical trabecular changes between LCH cases and controls. Multicenter studies with larger populations are needed to investigate the potential of FA in the identification of this rare disease.

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.

In vivo evaluation of mandibular trabecular and cortical bone quality in psoriasis vulgaris

OBJECTIVE

The aim of this study was to evaluate the effects of psoriasis vulgaris on mandibular structure by calculating fractal dimension (FD) and radiomorphometric indices.

STUDY DESIGN

Panoramic radiographs of 58 patients with psoriasis and 58 healthy participants were assessed. FD was used to analyze trabecular bone architecture in the condyle, angle, and 2 sites in the alveolar bone. Five radiomorphometric indices based on cortical thickness and the mandibular cortical index (MCI) for structure were used to assess cortical bone porosity. Comparisons were made between sites in trabecular and cortical bone. Quantitative and categorical data were statistically analyzed with the significance level at P < .05.

RESULTS

FD was significantly lower in the patients with psoriasis than in the controls in the alveolar bone sites (P ≤ .035). Differences between measurement sites were insignificant in psoriasis (P ≥ .617), but the FD values of some measurement sides in the control group differed significantly (P ≤ .004). All quantitative radiomorphometric indices were significantly lower in patients with psoriasis (P ≤ .034) with significant differences between some sites in both groups. No significant difference was found in MCI frequency distribution between the groups (P = .782).

CONCLUSIONS

Trabecular architecture and cortical thickness were negatively affected in patients with psoriasis, but no differences in cortical porosity were detected between groups.

Effects of reverse headgear therapy on mandibular trabecular structure: A fractal analysis study

OBJECTIVES

The aim of this study was to assess the effects of reverse headgear (RHG) treatment combined with rapid maxillary expansion (RME) on the trabecular structure of the mandibula using fractal dimension (FD) analysis.

METHODS

Forty-four individuals with skeletal Class III malocclusion were selected from the archives and divided into two groups as patients who underwent treatment with RME + RHG (RHG-G, 22 patients) and untreated control group (C-G, 22 patients). The before (T0) and after (T1) treatment lateral cephalometric and panoramic radiographs were collected in the RHG-G and in the control group, radiographs obtained with similar time intervals were grouped as T0 and T1. Cephalometric and FD analysis was conducted on T0 and T1 lateral cephalometric and panoramic radiographs. The intragroup comparison of cephalometric and FD data was performed using paired t test and Wilcoxon Signed Ranks test, while independent t test and Mann-Whitney U test were used for intergroup comparison.

RESULTS

C-G had higher FD values in the right mandibular corpus and left mandibular ramus values at T0 (P < .05). The only significant difference in the intragroup comparisons was detected in the FD values of the right mandibular corpus in the C-G (P < .05). No significant differences were found in the FD between the groups in any of the areas measured (P > .05).

CONCLUSIONS

RME + RHG therapy did not cause any significant trabecular changes in the mandibula when compared to the control group.

Fractal dimension analysis on CBCT scans for detecting low bone mineral density in postmenopausal women

Purpose

The aim of this study was to compare the fractal dimension (FD) measured at 2 bone sites (second cervical vertebra and mandible) on cone-beam computed tomography (CBCT). The research question was whether FD could serve as an accessory tool to refer postmenopausal women for densitometric analysis. Therefore, the reliability and accuracy of FD were evaluated.

Materials and Methods

In total, 103 postmenopausal women were evaluated, of whom 52 had normal bone mineral density and 51 had osteoporosis, according to dual X-ray absorptiometry of the lumbar spine and hip. On the CBCT scans, 2 regions of interest were selected for FD analysis: 1 at the second cervical vertebra and 1 located at the mandible. The correlations between both measurements, intra- and inter-observer agreement, and the accuracy of the measurements were calculated. A P value less than 0.05 was considered to indicate statistical significance for all tests.

Results

The mean FD values were significantly lower at the mandibular region of interest in osteoporotic patients than in individuals with normal bone mineral density. The areas under the curve were 0.644 (P=0.008) and 0.531 (P=0.720) for the mandibular and vertebral sites, respectively.

Conclusion

FD at the vertebral site could not be used as an adjuvant tool to refer women for osteoporosis investigation. Although FD differed between women with normal BMD and osteoporosis at the mandibular site, it demonstrated low accuracy and reliability.

Digital panoramic radiography as a tool for analyzing the quality of trabecular bone microarchitecture

Abstract Introduction Osteoporosis is a metabolic disease characterized by reduced bone mineral density, often accompanied by loss of quality of trabecular bone microarchitecture. Objective To assess the quality or degradation of trabecular bone microarchitecture in digital panoramic radiography to better predict the risk of fragility fractures. Material and method The sample included 68 female patients, age-matched, and divided into three groups according to densitometric results. Trabecular Bone Score values were measured and digital panoramic radiographs were taken. Fractal analysis with box counting was conducted in the region of premolars and angle of the mandible, with regions of interest measuring 64×64 and 80×120 pixels. In the statistical analysis, Pearson’s correlation was applied between the Trabecular Bone Score and fractal analysis results obtained in each group, using age as a control variable and assigning individualized age ranges within groups. Result A moderate correlation was identified in the regions of interest of 64×64 and 80×120 pixels at the angle of the mandible in the osteoporosis group and in the normal group. A moderate correlation was also obtained using age as a control variable in the 64x64 pixel regions of interest in the premolar region. Considering age range, the within-group analysis presented a strong correlation in the osteoporosis group and moderate correlation in the osteopenia and normal groups. Conclusion Fractal analysis in digital panoramic radiographs was shown to be a promising predictive instrument of bone microarchitecture quality.

Is jaw fractal dimension a reliable biomarker for osteoporosis screening? A systematic review and meta-analysis of diagnostic test accuracy studies

OBJECTIVES

To summarize the evidence on the feasibility of maxillomandibular imaging exams-related fractal dimension (FD) in screening patients with osteoporosis.

METHODS

This registered systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses of Diagnostic Test Accuracy statement. High sensitivity search strategies were developed for six primary databases and grey literature. Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) items evaluated the risk of bias, and the GRADE approach assessed the evidence certainty.

RESULTS

From 1034 records initially identified through database searching, four studies were included (total sample of 747 patients [osteoporosis, 136; control group, 611]). The meta-analysis showed that the overall sensitivity and specificity of the FD were 86.17 and 72.68%, respectively. In general, all studies showed low RoB and applicability concern. The certainty of the evidence was very low to moderate.

CONCLUSIONS

This systematic review showed that the jaw-related FD presented sensitivity and specificity values higher than 70%, and its sensitivity in osteoporosis screening was a better parameter than specificity.

Proton pump inhibitors and mandibular bone quality: A preliminary study

OBJECTIVES

Proton pump inhibitors (PPI) provide a long-lasting anti-acidic effect by inhibiting the proton pump, and they are one of the most commonly prescribed drugs worldwide. PPIs adversely affect the bone structure via deficiency of vitamins and minerals. The aim of this study was to investigate the possible PPI-induced bone changes in the mandible on panoramic radiographs with the methods of fractal analysis and panoramic morphometric indices.

METHODS

Panoramic radiographs of 402 patients were used (201 PPI users, 201 control group). Fractal analysis was performed on 4 regions of interests (ROI): 1- upper part of the ramus, 2- angulus, 3- anterior of the mental foramen, 4- distal of the middle ramus. Also, the panoramic mandibular index (PMI), mandibular cortical width (MCW), and Klemetti index (KI) were performed on radiographs.

RESULTS

There were significant differences in terms of ROI3, MCW, and KI between the control and study groups (p < 0.05) while there was no significant difference for ROI1, ROI2, ROI4, and PMI (p > 0.05). Males were severely affected than females.

CONCLUSIONS

Osteoporotic changes were detected in the trabecular and cortical bone in the mental foramen region in PPI users with fractal analysis and morphometric indices, while there were no differences for mandibular ramus and angulus regions according to fractal analysis.

Fractal analysis of the trabecular bone pattern in the presence/absence of metal artifact-producing objects: Comparison of cone-beam computed tomography with panoramic and periapical radiography

OBJECTIVES

The effect of metallic objects on the fractal dimension (FD), bone area fraction (BAF) and gray scale values (GSVs) of cone-beam CT (CBCT) images was assessed. Also, FD, BAF and GSV were compared among CBCT, digital periapical and panoramic radiographies.

METHODS

Digital periapical and panoramic radiographs were acquired from six blocks of bovine rib. Additionally, different arrangements of titanium implants and intracanal metallic posts were created in the bone blocks and CBCT scans were taken from the different implant-root arrangements. The three radiographical modalities were compared by analysis of variance. Pairwise comparisons between the modalities were performed by the Tukey test (significance level set at 0.05).

RESULTS

Different root-implant arrangements in the CBCT images revealed no significant differences in the FD (p = 0.920), BAF and GSV values (p = 0.623). FD differed significantly among the three modalities (p < 0.001). Significant differences were found between CBCT and each of the periapical and panoramic techniques (p < 0.001), while no remarkable differences were observed in the FD of the periapical and panoramic images (p = 0.294). BAF and GSV showed significantly different results among the three radiographical techniques (p < 0.001). The difference was remarkable between CBCT and periapical (p < 0.001), CBCT and panoramic (p < 0.001) and periapical and panoramic (p = 0.008).

CONCLUSION

Presence of titanium implants and intracanal posts does not produce different results in the fractal analysis (FA) of the CBCT images. The trabecular bone pattern is best assessed by FA of the periapical radiographs followed by the panoramic and CBCT techniques, respectively.

Use of fractal analysis in dental images for osteoporosis detection: a systematic review and meta-analysis

Fractal dimension (FD) calculated on oral radiographs has been proposed as a useful tool to screen for osteoporosis. This systematic review and meta-analysis firstly aimed at assessing the reliability of FD measures in distinguishing osteoporotic patients (OP) from healthy controls (HC), and secondly, to identify a standardized procedure of FD calculation in dental radiographs for the possible use as a surrogate measure of osteoporosis. A comprehensive search was conducted up to September 2020 using PubMed, Web of Science, and SCOPUS databases. The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement was followed. Meta-analysis was performed on FD values calculated for HC and OP. Overall, 293 articles were identified. After a three steps screening, 19 studies were included in the qualitative appraisal and 12 were considered for meta-analysis. The methodological quality of the retrieved studies was generally low. Most of the studies included used White and Rudolph and box counting to process the images and to calculate FD, respectively. Overall, 51% of the studies found a meaningful difference between HC and OP groups. Meta-analyses showed that to date, FD measures on dental radiographs are not able to distinguish the OP from HC group significantly. From the current evidence, the use of FD for the identification of OP is not reliable, and no clear conclusion can be drawn due to the heterogeneity of studies. The present review revealed the need for further studies and provided the fundamentals to design them in order to find a standardized procedure for FD calculation (regions for FD assessment; images processing technique; methods for FD measurement). More effort should be made to identify osteoporosis using dental images which are cheap and routinely taken during periodic dental examinations.

Evaluation of trabecular bone healing using fractal dimension analysis after augmentation of alveolar crests with autogenous bone grafts: a preliminary study

OBJECTIVE

The aim of this study is to evaluate bone remodeling after alveolar crest augmentation with autogenous bone grafts.

METHODS

50 patients who were applied augmentation due to alveolar deficiency were included in this study. Fractal dimensions were measured on the radiographs in the preoperative, postoperative, follow-up periods. The ROI was selected specific to each patient, but repeated in a standardized manner on subsequent radiographs.

RESULTS

A total of 50 patients were included in the study; There were 31 females and 19 males. Implants were placed in all patients without any complications. The mean fractal dimensions on the graft recipient side were statistically higher in the postoperative 5th month compared to the postoperative 1st week (p = 0.002). The mean fractal dimensions on the donor side were statistically higher in the preoperative and postoperative 5th month compared to the postoperative 1st week (p < 0.001).

CONCLUSION

Any clinical imaging method cannot fully reflect the histological microstructures of the bone. Evaluating the fractal analysis together with the clinical results can demonstrate adequate bone healing and quality prior to implant placement. Fractal analysis is a non-invasive, reproducible, method but further, prospective, randomized, controlled clinical studies are needed to estimate bone quality prior to implant placement.

Fractal dimension in CBCT images as predictor for MRONJ: a retrospective cohort study

Objective

To estimate boxcounting fractal dimension in a standardized approach in CBCT images of the mandible and maxilla in a group of patients with MRONJ in comparison to a healthy control group.

Material and methods

From our records, a study group consisting of 80 maxillary and mandibular CBCTs in 77 cases of patients having MRONJ was collected. The control group consisted of 84 mandibular and maxillary CBCTs in a total of 78 patients. Using the boxcounting method, fractal dimension (FD) was estimated in a standardized fashion either cranially to the apex of the canine (maxilla) or beneath the tooth apices of the lower molars in the bone area above the mandibular canal (mandible). Intra-observer reproducibility of the FD-measurements was assessed by 6 repeated measurements in 10 individuals. FD values were correlated to age and sex of the individuals as well as to region of interest (ROI) sizes.

Results

FD in the study group (1.684 ± 0.051) was roughly 3.5 % lower than in the control group (1.745 ± 0.026, p < 0.0001). Sex and age had a significant (p < 0.001) influence on FD values in the study group, yet not in the control group. FD values increased with age (study group, spearman-rho: 0.2895, p < 0.05) and also ROI size (both groups, p < 0.0001). Reproducibility was good (intra-class correlation coefficient (ICC): 0.87).

Conclusions

Fractal dimension as assessed by boxcounting seems to be a good descriptor for MRONJ in jaw bones. Influence of age and sex on the outcome values needs to be further investigated in future studies.

Clinical relevance

CBCTs could be assessed with respect to FD to obtain an overview of the disease status of MRONJ patients.

Effect of total edentulism on the internal bone structure of mandibular condyle: a preliminary study

OBJECTIVE

The aim of this study was to assess the internal structure of the mandibular condyles in patients with total edentulism by applying fractal analysis on cone-beam computed tomography (CBCT) images and compare with dentate subjects.

METHODS

A total of 136 mandibular condyles were assessed. All CBCT images were prepared with 0.25-mm slice thickness and maximum magnification. A 64 × 64 pixel region of interest (ROI) within the trabecular bone in the center of the condyle was selected. Fractal analysis was performed using White and Rudolph's box-counting method.

RESULTS

Control and study groups were age and gender-matched. The mean fractal dimension (FD) value of the study group was significantly lower compared to the control group (p < 0.01). In the study group, the mean FD value of the females was significantly lower than males (p = 0.01). For the control group, there was no significant difference between the genders for FD (p = 0.11). There was no significant difference between the age subgroups of the female study group and the male control group for FD (p = 0.22, p = 0.33). The mean FD value of the younger age subgroup was significantly higher compared to the older age subgroup in the female control and male study group (p = 0.03, p = 0.01).

CONCLUSION

The internal bone structure of mandibular condyles in edentulous patients was found to be affected by edentulism. Fractal analysis can be used as an effective method for assessing temporomandibular joint health.

Mandibular radiomorphometric parameters of women with cemento-osseous dysplasia

OBJECTIVE

To compare the radiomorphometric parameters of mandibular trabecular and cortical bone of females with and without cemento-osseous dysplasia (COD).

METHODS

A retrospective cross-sectional paired study was conducted. Digital panoramic radiographs were obtained from females diagnosed in a public service of Oral Medicine. The participants were divided into two groups of 50 subjects each: females with a diagnosis of COD (COD group) and females without a diagnosis of COD (non-COD group), randomly chosen from the image database and paired for age. The radiomorphometric parameters analyzed were: mandibular cortical width (MCW), fractal dimension (FD) and mandibular cortical index (MCI). The paired t-test and Wilcoxon test were used to compare MCW and FD values and the McNemar-Bowker test compared the MCI.

RESULTS

The mean age of both groups was 46.84 ± 11.38 years. The median MCW index was 3.12 mm (2.15-4.55) for the COD group and 3.52 mm (1.90-4.70) for the non-COD group (p = 0.034). The mean FD value of the COD group (1.2039 ± 0.0926) was lower than that of the non-COD group (1.2472 ± 0.0894) in the anatomical region of the interest of mandibular cortical bone (p = 0.031), while no difference was detected in alveolar trabecular bone. The C3 degree of MCI was more frequent in the COD group (p = 0.009).

CONCLUSION

Females with COD had lower values of radiomorphometric parameters in mandibular cortical bone than females of the same age without COD. These results suggest that, in addition to the dental care recommended in the literature, COD females also require more attention and screening for low bone mineral density.

Evaluation of the mandibular trabecular bone in patients with bruxism using fractal analysis

OBJECTIVE

The aims of this study were (1) to investigate the effect of bruxism on the fractal dimension (FD) of the mandibular trabecular bone through digital panoramic radiographs, and (2) to evaluate the effectiveness of fractal analysis as a diagnostic test for bruxism.

METHODS

One hundred and six bruxer and 106 non-bruxer patients were included in the study. Three bilateral regions of interest (ROI) were selected: ROI-1, the mandibular condyle; ROI-2, the mandibular angle; ROI-3, the-area between the apical regions of the mandibular second premolar and the first molar teeth. FD values for the bruxer and non-bruxer groups were compared for each ROI.

RESULTS

Only the FD measurements for the right mandibular condyle (ROI-1) showed a statistically significant difference (p = 0.041) between the bruxer and non-bruxer individuals. FD values measured in the bruxers (1.40 ± 0.09) were lower than in the non-bruxers (1.42 ± 0.08).

CONCLUSION

Fractal analysis may be a useful method for discerning trabecular differences in the condylar areas of bruxer individuals. In future studies, the unilateral mastication habits, the characteristics of dental wear, and the occlusal bite forces of individuals should be documented.

A new cone-beam computed tomography-driven index for osteoporosis prediction

OBJECTIVE

To verify whether mandibular cortical analyses accurately distinguish postmenopausal women with normal bone mineral density (BMD) from women with osteoporosis by means of a cone-beam computed tomography (CBCT)-driven composite osteoporosis index (three-dimensional mandibular osteoporosis index-3D MOI).

MATERIAL AND METHODS

The comparison was performed between 52 women with normal BMD and 51 women with osteoporosis according to dual-energy X-ray absorptiometry (DXA) examination of the lumbar spine and hip. Mandibular cortical width (MCW) and cortical quality were evaluated on cross-sectional and panoramic reconstructed images. ANOVA, ROC curves and accuracy measurements were used for statistical analyses, as well as a predictive model combining the quantitative and qualitative analyses and age.

RESULTS

All CBCT-driven measurements presented good to moderate intra- and interobserver agreements. MCW values were significantly lower in women with osteoporosis. Postmenopausal women with osteoporosis were 8 times more likely to have the cortex classified as C3, and 2.4 times more likely to have MCW thinner than 2.75 mm. The area under the ROC curve was 0.8 for the predictive model.

CONCLUSIONS

The newly developed 3D MOI enables distinguishing women with osteoporosis from those with normal BMD with good sensitivity and specificity.

CLINICAL RELEVANCE

Whenever a CBCT scan is performed for specific clinical indications, a 3D MOI may be performed to qualitatively and quantitatively assess the condition of the mandibular cortex. This may be surely helpful to assess the osteoporosis status in the ageing population and more specifically in peri- or postmenopausal women.

The effect of selective serotonin reuptake inhibitors on the human mandible

OBJECTIVES

Selective serotonin reuptake inhibitors (SSRI) are a group of drugs that selectively and strongly block the serotonin transporter. Aim of this study was to evaluate the mandibular bone structure of patients who are using SSRIs with fractal analysis and panoramic morphometric indices [mandibular cortical width (MCW), panoramic mandibular index (PMI) and Klemetti index (KI)] and to compare with control group.

METHODS

Patients who declared using SSRIs for more than six months had been included in the study group. In total, 212 dental panoramic radiographs (DPR) were assessed. For fractal analysis; three regions of interest (ROIs) were determined: ROI1 and ROI2 were chosen within trabecular bone, ROI3 was selected from cortical bone. MCW, PMI, and KI were obtained from DPRs. The study group was categorized into five subgroups of various SSRIs. The fractal dimension (FD) values and panoramic morphometric indices of these subgroups were also compared.

RESULTS

There was no significant difference between the groups for age and gender (p = 0.57, p = 0.5). There were significant differences in the mean FD values between the study and control groups both for the ROI1 and ROI2 (p < 0.01, p < 0.01). There was no significant difference between the groups for the mean FD value of ROI3, MCW, PMI and KI (p = 0.93, p = 0.98, p = 0.74, p = 0.06). There were no significant differences for all the values between the SSRI subgroups (p = 0.52, p = 0.7, p = 0.76, p = 0.24, p = 0.31, p = 0.08) CONCLUSIONS: Trabecular rich sites of the mandible were found to be affected by SSRI usage.

Evaluation of bone texture imaging parameters on panoramic radiographs of patients with Sheehan's syndrome: a STROBE-compliant case-control study

Sheehan's syndrome (SHS) is a rare condition related to the risk of osteoporosis and evaluation of bone texture imaging features on panoramic radiographs would be suitable for this condition, which was the aim of the present study. Fractal dimension, lacunarity, and trabecular morphologic aspects were significantly altered in these patients.

INTRODUCTION

SHS is an important public health problem particularly in developing countries. It is characterized as postpartum hypopituitarism secondary to obstetric complications-related ischemic pituitary necrosis that shows significant systemic metabolic repercussions. Thus, this study aimed to evaluate bone texture parameters in digital panoramic radiographs of patients with SHS.

METHODS

A case-control study was conducted with 30 SHS patients from an Endocrinology and Diabetology Service of reference in Brazil, and 30 age- and sex-matched healthy controls. A custom computer program measured fractal dimension, lacunarity, and some morphologic features in the following mandibular regions of interest (50 × 50 pixels): below the mental foramen (F1), between the first and second molars (M1), and at the center of the mandibular ramus (R1).

RESULTS

The fractal analysis showed a statistically significant difference between the studied groups in all regions of interest. The fractal dimension in F1 (p = 0.016), M1 (p = 0.043), and R1 (p = 0.028) was significantly lower in SHS group, as well as lacunarity in R1 (p = 0.008). Additionally, several morphologic features were statistically significant in the SHS group (p < 0.05).

CONCLUSION

Therefore, individuals with SHS showed altered imaging texture parameters on panoramic radiographs, which reflect a smaller spatial organization of the bone trabeculae and, possibly, a state of reduced mineral bone density.

Use of fractal analysis in dental images: a systematic review

OBJECTIVES

This study reviewed the use of fractal analysis (FA) in dental images.

METHODS

A search was performed using PubMed, MEDLINE, LILACS, Web of Science and SCOPUS databases. The inclusion criteria were human studies in the English language, with no date restriction.

RESULTS

78 articles were found in which FA was applied to panoramic radiographs (34), periapical radiographs (21), bitewing radiographs (4), cephalometric radiograph (1), cone beam CT (15), micro-CT (3), sialography (2), and ultrasound (2). Low bone mineral density (21) and systemic or local diseases (22) around the bone of dental implants were the main subjects of the study of FA. Various sizes and sites of the regions of interest were used to evaluate the bone structure. Different ways were used to treat the image and to calculate FA. FA of 43 articles showed significant differences in the comparison of groups, mainly between healthy and sick patients.

CONCLUSIONS

FA in Dentistry has been widely applied to the study of images. Panoramic and periapical radiographs were those most frequently used. The Image J software and the box-counting method were extensively adopted in the studies reviewed herein. Further studies are encouraged to improve clarification of the parameters that directly influence FA.

Mandibular indexes and fractal properties on the panoramic radiographs of the patients using aromatase inhibitors

OBJECTIVE:

This study was conducted to evaluate fractal dimension (FD), mandibular cortical width (MCW), panoramic mandibular index (PMI), and mandibular cortical index (MCI) on panoramic radiographs to determine the mandibular cortical and trabecular bone changes in females with breast cancer undergoing aromatase inhibitors (AIs) treatment.

METHODS:

In this retrospective study, FD analysis, PMI, MCI, and MCW were assessed over panoramic radiographs of 34 females under AI therapy as a patient group and 34 healthy age-gender matched individuals as a control group.

RESULTS:

Mean FD values and MCW were slightly but not significantly lower in the patient group (1.47 ± 0.06 and 4.1 ± 1.2 respectively). FDs measured onthe supracortical area above the angulus mandibula (FD2) and anterior to the mental foramen (FD4) were significantly lower in patients (p = 0.037 and p = 0.046 respectively). Among the measured regions in patients, FD2 was significantly lower (p = 0.001). PMI was also significantly lower in patients (p = 0.001) and MCI were similar in both groups (p = 0.604).

CONCLUSION:

AI use affects bone quality and evaluating FD, PMI, and MCW in panoramic radiography can be used to determine the effect of this drug on the jaw bones in the early period.

ADVANCES IN KNOWLEDGE:

Aromatase inhibitors are the most commonly used drugs in breast cancer patients. This drug is thought to have osteoporotic effects on the jawbone. This study is the first study to evaluate osteoporotic changes with measurements made on panoramic radiographs and the results of the study are significant. We think this study will shed light on the studies that will investigate the effects of the drug on the jaw bones.

Comparison of fractal dimension analysis and panoramic-based radiomorphometric indices in the assessment of mandibular bone changes in patients with type 1 and type 2 diabetes mellitus

OBJECTIVES

This study compared the fractal dimension (FD) and radiomorphometric indices in the assessment of mandibular bone of patients with type 1 (T1 DM) and type 2 diabetes mellitus (T2 DM).

STUDY DESIGN

Panoramic radiographs of 104 patients were evaluated to calculate FD, mandibular cortical width (MCW), panoramic mandibular index (PMI), and mandibular cortical index (MCI) in the mandible.

RESULTS

No statistically significant differences were found in FD when T1 DM and T2 DM groups were compared with controls (P ≥ .168). Patients with T1 DM had significantly lower MCW (P < .001) and PMI (P = .030) compared with controls. Patients with T2 DM had no significant differences in MCW (P = .228) or PMI (P = .137) compared with controls. No significant differences were observed between patients with T1 DM and those with T2 DM for FD, MCW, and PMI (P > .05). In the T1 DM and T2 DM groups, there was a significant correlation between MCW and FD (P ≤ .011). No correlation was observed between FD and PMI in either the T1 DM group or the T2 DM group (P ≥ .142). No significant differences in MCI were observed between the DM groups and controls (P = .740) or between the T1 DM and T2 DM groups (P = 1.000).

CONCLUSIONS

The cortical and trabecular bone architectures of patients with T1 DM and T2 DM were not different. Patients with T1 DM had lower cortical measurements compared with controls.

Capability of CBCT to identify patients with low bone mineral density: a systematic review

The aim of this study was to systematically review the literature about the capability of CBCT images to identify individuals with low bone mineral density (BMD). As the literature is scarce regarding this topic, the purpose of this systematic review is also to guide future research in this area. A detailed search was performed in five databases without restrictions of time or languages. Additionally, a grey literature search was conducted. The Quality Assessment Tool for Diagnostic Accuracy Studies-2 was applied to evaluate the methodological design of selected studies. With the inclusion of only six studies, the evidence is limited to endorse the use of CBCT assertively as a diagnostic tool for low BMD. All of the three studies that analyzed radiomorphometric indices found that the linear measurements of the mandibular inferior cortex were lower in osteoporotic individuals. CBCT-derived radiographic density vertebral and mandibular measurements were also capable for differentiating individuals with osteoporosis from individuals with normal BMD. The analysis of the cervical vertebrae showed high accuracy measurements. This systematic review indicates a scarcity of studies regarding the potential of CBCT for screening individuals with low BMD. However, the studies indicate that radiomorphometric indices and CBCT-derived radiographic density should be promising tools for differentiating individuals with osteoporosis from individuals with normal BMD.

Is the panoramic mandibular index useful for bone quality evaluation?

Purpose

The aim of this study was to determine whether the panoramic mandibular index (PMI) is useful for assessing bone mineral density. We also analyzed the potential correlations between PMI parameters and patient age.

Materials and Methods

Four observers measured the PMI of both sides of the mental foramen using a picture archiving and communication system and images in the Digital Imaging and Communications in Medicine format. They studied 300 panoramic radiographic images of patients belonging to the following age groups: 40–49 years, 50–59 years, 60–69 years, 70–79 years, and 80–89 years. The observers were allowed to zoom in or out and to adjust the contrast of the images. Further, they were instructed to record the reasons for any measurements that could not be made. Then, we conducted a reliability analysis of the measured PMI and assessed the correlations between different patient age groups and the 3 parameters used for determining the PMI from the available data.

Results

Among the 600 data items collected, 23 items were considered unmeasurable by at least 1 observer for the following 4 reasons: postoperative state, lesion, unidentified mental foramen, and alveolar bone loss. The intraobserver reproducibility of the measurable data was 0.611-0.752. The mandibular cortical width (MCW) decreased significantly as patient age increased.

Conclusion

PMI had limited usability when the margin of the mental foramen was not clear. In contrast, MCW, a parameter used for determining the PMI, had fewer drawbacks than the PMI with respect to bone mineral density measurements and exhibited a significant correlation with patient age.

Distributional Variations in the Quantitative Cortical and Trabecular Bone Radiographic Measurements of Mandible, between Male and Female Populations of Korea, and its Utilization

It is important to investigate the irregularities in aging-associated changes in bone, between men and women for bone strength and osteoporosis. The purpose of this study was to characterize the changes and associations of mandibular cortical and trabecular bone measures of men and women based on age and to the evaluation of cortical shape categories, in a large Korean population. Panoramic radiographs of 1047 subjects (603 women and 444 men) aged between 15 to 90 years were used. Mandibular cortical width (MCW), mandibular cortical index (MCI), and fractal dimensions (FD) of the molar, premolar, and anterior regions of the mandibular trabecular bone were measured. Study subjects were grouped into six 10-years age groups. A local linear regression smoothing with bootstrap resampling for robust fitting of data was used to estimate the relationship between radiographic mandibular variables and age groups as well as genders. The mean age of women (49.56 ± 19.5 years) was significantly higher than that of men (45.57 ± 19.6 years). The MCW of men and women (3.17mm and 2.91mm, respectively, p < 0.0001) was strongly associated with age and MCI. Indeed, trabecular measures also correlated with age in men (r > −0.140, p = 0.003), though not as strongly as in women (r > −0.210, p < 0.0001). In men aged over 55 years, only MCW was significantly associated (r = −0.412, p < 0.0001). Furthermore, by comparison of mandibular variables from different age groups and MCI categories, the results suggest that MCW was detected to be strongly associated in both men and women for the detection of bone strength and osteoporosis. The FD measures revealed relatively higher association with age among women than men, but not as strong as MCW.

IDIOS: An innovative index for evaluating dental imaging-based osteoporosis screening indices

Purpose

The goal of this study was to develop a new index as an objective reference for evaluating current and newly developed indices used for osteoporosis screening based on dental images. Its name; IDIOS, stands for Index of Dental-imaging Indices of Osteoporosis Screening.

Materials and Methods

A comprehensive PubMed search was conducted to retrieve studies on dental imaging-based indices for osteoporosis screening. The results of the eligible studies, along with other relevant criteria, were used to develop IDIOS, which has scores ranging from 0 (0%) to 15 (100%). The indices presented in the studies we included were then evaluated using IDIOS.

Results

The 104 studies that were included utilized 24, 4, and 9 indices derived from panoramic, periapical, and computed tomographic/cone-beam computed tomographic techniques, respectively. The IDIOS scores for these indices ranged from 0 (0%) to 11.75 (78.32%).

Conclusion

IDIOS is a valuable reference index that facilitates the evaluation of other dental imaging-based osteoporosis screening indices. Furthermore, IDIOS can be utilized to evaluate the accuracy of newly developed indices.

Feasibility of cone beam computed tomography radiomorphometric analysis and fractal dimension in assessment of postmenopausal osteoporosis in correlation with dual X-ray absorptiometry

OBJECTIVES

The aim of the present study was to assess the feasibility of using mandibular CBCT radiomorphometric indices and box-counting fractal dimension (FD) to detect osteoporosis in post-menopausal females, compare them with the healthy control group and to correlate the findings with the bone mineral density measured by dual X-ray absorptiometry (DXA).

METHODS

This study consisted of 50 post-menopausal females, with age ranging from 55 to 70 years. Based on their DXA results, they were classified into osteoporotic and control groups. Mandibular CBCT radiomorphomertic indices and FD analysis were measured.

RESULTS

Significant differences were found for the CT cortical index scores (CTCI), CT mental index (CTMI) and CT mandibular index (CTI) between the control and osteoporotic groups. The control group showed higher mean values than the osteoporotic group. For FD values, no significant differences were found between the two groups.

CONCLUSIONS

CBCT radiomorphometric indices could be used as an adjuvant tool to refer patients at risk of osteoporosis for further assessment.