Prediction of age-related osteoporosis using fractal analysis on panoramic radiographs

Y. Strut and radio-morphometric analysis of mandibular trabecular structure in pre-and post-menopausal women to aid in the diagnosis of osteoporosis

Purpose

The purpose of the study is to evaluate the mandibular trabecular pattern in pre- and postmenopausal age women. By analysing the strut, fractal, grey level co-occurrence matrix, and radio-morphometric indices in the panoramic radiograph.

Method

Panoramic radiographs from 2019 to 2022 were used to assess pre- and postmenopausal women's bone mineral density. A total of 272 panoramic radiographs, which exhibited clear visibility of the mental foramen on both sides without any blurring, motion artefacts, surgical errors, overlapping hyoid bone, or inferior mandibular cortex, were divided into two groups. Group A (136 premenopausal women) and Group B (136 postmenopausal women). It is a retrospective study that is non-interventional/observational in design. Strut features, fractal dimensions, a grey-level co-occurrence matrix, and radio morphometric indices were used to investigate bone texture in an image processing program. The mean difference between group variables was calculated using an independent sample t-test/unpaired t-test.

Results

Pre-menopausal women had a mean age of 38.83 ± 6.01 years, while postmenopausal women had a mean age of 68.26 ± 8.31 In the postmenopausal group Four regions of interest exhibited fractal dimensions with a P value of less than 0.01 and GLCM features including contrast (0.812), correlation (0.230), energy (0.215), and homogeneity (0.322). Strut features of the four regions showed that 15 of 19 characteristics were significantly different.

Conclusion

Orthopantomogram is useful in screening for osteoporosis. Strut, radio-morphometric indices, and fractal analysis can assess bone texture and quality. Future research incorporating artificial intelligence can revolutionize image analysis and support clinical decision-making.

Direct-Acting Oral Anticoagulant/Vitamin K Antagonists: Do They Affect the Trabecular and Cortical Structure of the Mandible?

BACKGROUND

This study aimed to evaluate the mandibular bone structure of patients using oral anticoagulants (OACs) vitamin K antagonist drugs (warfarin) and other OACs including direct oral anticoagulants [(DOACs) apixaban, rivaroxaban, dabigatran, edoxaban]. Analyses were based upon the fractal dimension (FD), the panoramic mandibular index (PMI) and the Klemetti index (KI), which is also known as the mandibular cortical index (MCI).

METHODOLOGY

Ninety participants were divided into three groups: group 1: 30 systemically healthy individuals who had not used any anticoagulants before, group 2: 30 individuals using warfarin, and group 3: 30 individuals using DOACs. FD was used to analyze trabecular bone architecture in the condyle, angle, and two sites in the alveolar bone. PMI was used to evaluate the quantity of cortical bone and KI was used to evaluate the cortical bone quality.

RESULTS

There was no difference between the groups regarding FD analysis and KI; however, a difference was found between groups 1, 2, and 3 in the PMI (P≤ 0.001). The PMI in group 1 was higher than in groups 2 and 3.

CONCLUSION

Mandibular radiomorphometric indices can be used on panoramic radiographs to evaluate the quantity of mandibular cortical bone in patients using oral anticoagulants.

Assessment of mandibular trabecular structure and cervical vertebral maturation using fractal analysis

BACKGROUND

Changes in bone trabeculae occur during skeletal maturation. Fractal analysis is a technique for assessing changes in the internal structure of the bone.

OBJECTIVE

The aim of this study was to investigate correlation of bone trabeculation measured on panoramic and lateral cephalometric radiographs with cervical vertebral maturation stages (CVMS).

METHODS

CVMS was evaluated on lateral cephalometric radiographs of 120 individuals aged 6 to 18 years. The subjects were divided into 6 groups (n= 20 each) according to CVMS. On panoramic and lateral cephalometric radiographs, fractal dimension (FD) analyses were performed in mandibular corpus, gonial and condylar regions and cervical vertebral bodies (C2, C3, C4).

RESULTS

FD measurements from the mandibular corpus region bilaterally and C2-C4 vertebral bodies showed significant positive correlations with CVMS (r= 0.418, r= 0.412, r= 0.324, r= 0.304, r= 0.263, respectively). Significant differences were found in the FD values of the right/left mandibular corpus and C2 and C3 vertebrae compared to CVMS (P< 0.001, P< 0.001, P= 0.005, P= 0.019, respectively).

CONCLUSION

Significant positive moderate correlations between the FD values of the right and left mandibular corpus and CVMS suggest that fractal analysis may be useful in determining skeletal maturity stage. The significant FD values obtained from the right/left mandibular corpus, and C2 and C3 vertebra indicate that the complexity of the internal trabecular structure increases with maturation.

Multifractal approach for a biological porous media: Human dentin case

A multifractal characterization to human dentin porosity is made. Micrographs of human dentin samples gotten from scanning electron microscopy (SEM) were studied in order to characterize porosity. We got the generalized dimensions (multifractal moments)D q for pore space and matrix skeleton on gray scale and binary images for samples of both gender. For the case, we found that superficial porosityη s is linked to mass fractal dimensionD 0 in an approximately linear relationship asD 0 ≈ η s + d ¯ for binary images. In addition, probability density distribution (PDD) for pore diameters is found a normal PDD type. Other quantities of interest like mean, standard deviation, maximum and minimum pore diameters, voit ratios, and percentage of chemical composition are reported. RESEARCH HIGHLIGHTS: SEM sample, images and procedure for multifractal analysis are detailed. Micro patterns in grayscale are multifractal and in binary scale are monofractals. Superficial porosity is relate to mass fractal dimension approximately linearly. From the porosity values, voit ratios are determined. Pores diameters obey a normal PDD.

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 trabecular bone in individuals with periodontitis using fractal analysis: An observational cross-sectional study

Background

It is very difficult to objectively evaluate the negative changes in bone structure due to periodontitis. The present study was aimed to evaluate the trabecular bone structure between healthy individuals and periodontitis patients by fractal analysis (FA) on digital panoramic radiographs.

Material and Methods

The study included 50 periodontally healthy individuals (control group), 50 individuals with Stage 1 periodontitis (S1-P group), 50 individuals with Stage 2 periodontitis (S2-P), and 50 individuals with Stage 3 periodontitis (S3-P), a total of 200 individuals were included. The fractal dimension (FD) value of the trabecular bone in the interdental space between mandibular first molar and second premolar tooth roots was evaluated using Image J program. The mean FD values of the two regions were calculated by box counting method.

Results

There was a statistically significant difference between the groups in terms of all periodontal parameter values (p<0.05). The mean FD values of individuals diagnosed with periodontitis were 1.36±0.08 in the S1-P group, 1.35±0.07 in the S2-P group, 1.28±0.15 in the S3-P group, and 1.44±0.06 in the control group. When the FD values between the groups were examined, it was seen that there was a statistically significant difference between the control and individuals with periodontitis, and the mean FD values were significantly higher in the healthy group (p<0.05). The best receiver operator curve was identified for periodontitis at the ≤1.409 cut-off FD value (area under the curve: 0.828; 95% CI: 0.758-0.899); p=0.000, p<0.001).

Conclusions

FD evaluation can give an objective result about the effect of periodontitis on alveolar bone. The FD values of trabecular bone are different in healthy individuals and individuals with different stages of periodontitis. The findings suggested that a negative correlation between the periodontal data with the sites in which FD was measured and as the periodontitis stage progresses, FD decreases. Key words:Diagnosis, Periodontal Diseases, Radiographic Evaluation.

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.

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.

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.

Evaluation of the compatibility of C2, C3, and C4 fractal dimension values with hand-wrist and cervical vertebra maturation methods in determining skeletal maturation

OBJECTIVES

To examine the correlation between the fractal dimension (FD) values of cervical vertebrae (C2, C3, and C4) and hand-wrist maturation (HWM) and cervical vertebra maturation (CVM) methods. In addition, the correlation between the pubertal growth spurt (PGS) and FD values was examined.

METHODS

The lateral cephalometric and hand-wrist radiographs of 120 subjects (61 females and 59 males) aged 8-18 years with a mean age of 13 years, were evaluated retrospectively. The CVM stages were determined in accordance with Hassel-Farman's modification of Lamparski criteria. The HWM stages were determined in accordance with Björk and Grave-Brown criteria. Both HWM and CVM stages were divided into two according to PGS. Fractal analysis of cervical vertebrae was performed according to the White-Rudolph method. The relationships between HWM stages, CVM stages and other variables were evaluated by Spearman's rank-order correlation coefficient. The relationships between FD values, chronological age, and divided stages were evaluated by the Pearson correlation coefficient. The Mann-Whitney U test was used to compare the FD values of two divided stages.

RESULTS

There were positive and statistically significant positive correlations between chronological age and both HWM and CVM stages. There was a positive and statistically significant correlation between CVM and HWM stages. In females and total, there were negative and statistically significant correlations between C4 FD values and divided HWM stages, and the differences between C4 FD values of divided HWM stages were also statistically significant. In total, there was a negative and statistically significant correlation between C4 FD values and divided CVM stages, and the difference between C4 FD values of divided CVM stages was also statistically significant.

CONCLUSION

The negative correlations found between C4 FD values and divided HWM and CVM stages suggest the fractal analysis of cervical vertebrae, especially of C4, may be used as an objective tool for evaluating the PGS.

Radiographic changes of mandibular cortical bone in bisphosphonate drug holiday

Objectives

There have been few studies to date on the residual effect of bisphosphonate. This study investigated the radiographic changes of mandibular cortical thickness upon bisphosphonate drug holiday.

Materials and Methods

This retrospective study includes 36 patients diagnosed with MRONJ (medication-related osteonecrosis of the jaw) at Ajou University Dental Hospital in 2010-2021. All patients stopped taking bisphosphonate under consultation with the prescribing physicians. Panoramic radiographs were taken at the start of discontinuation (T₀), 12 months after (T₁), and 18 months after (T₂) discontinuation of bisphosphonate, respectively. Mental index and panoramic mandibular index were calculated using Ledgerton’s method. Paired t-tests were used to analyze differences over time.

Results

The difference in indices (mental index and panoramic mandibular index) between T₀ and T₁ was not statistically significant (paired t-test, P>0.05). However, the difference in these indices between T₁ and T₂ was statistically significant (paired t-test, P<0.05).

Conclusion

The cortical thickness of the mandible decreased in the late stage (after 18 months) as observed by panoramic radiograph.

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.

Comparison of cone-beam computed tomography and digital panoramic radiography for detecting peri-implant alveolar bone changes using trabecular micro-structure analysis

Objectives

We compared changes in fractal dimension (FD) and grayscale value (GSV) of peri-implant alveolar bone on digital panoramic radiography (DPR) and cone-beam computed tomography (CBCT) immediately after implant surgery and 12 months postoperative.

Materials and Methods

In this retrospective study, 16 patients who received posterior mandibular area dental implants with CBCT scans taken about 2 weeks after implantation and one year after implantation were analyzed. A region of interest was selected for each patient. FDs and GSVs were evaluated immediately after implant surgery and at 12-month follow-up to examine the functional loading of the implants.

Results

There were no significant differences between DPR and CBCT measurements of FD values (P>0.05). No significant differences were observed between FD values and GSVs calculated after implant surgery and at the 12-month follow-up (P>0.05). GSVs were not correlated with FD values (P>0.05).

Conclusion

The DPR and reconstructed panoramic CBCT images exhibit similar image quality for the assessment of FD. There were no changes in FD values or GSVs of the peri-implant trabecular bone structure at the 12-month postoperative evaluation of the functional loading of the implant in comparison to values immediately after implantation. GSVs representing bone mass do not align with FD values that predict bone microstructural parameters. Therefore, GSVs and FDs should be considered different parameters for assessing bone 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.

Structural changes in the trabecular bone of the mandibular condyle of growing patients with sagittal jaw discrepancy treated with the twin-block appliance

OBJECTIVE

The objective of this study was to evaluate the structural changes in the trabecular bone of the mandibular condyles in patients treated with the Twin-block functional orthopaedic appliance that act by promoting condylar growth and to compare the fractal dimension (FD) of condylar trabecular bone structure prior to treatment (T0) and after orthopaedic functional treatment (T1).

SETTING AND SAMPLE POPULATION

This retrospective study included panoramic images of 112 individuals with a mean age of 11.04 ± 1.30 years in the study group (32 girls and 24 boys) and 11.6 ± .80 years in the control group (29 girls and 27 boys).

MATERIALS AND METHODS

The standardized region of interest was selected as the right and left condylar areas close to the articulation surfaces from the twin-block (TB) group, which included patients who completed functional orthopaedic treatment and the control group, which included untreated individuals. FD values in the condylar region were analysed from the panoramic radiographs of both groups using a box-counting method with ImageJ software (version 1.52a, US National Institutes of Health).

RESULTS

There was a significant decrease in the FD values of the right (-.038) and left (-.022) condylar region at T0 and T1 in the TB group. Between-group FD comparisons demonstrated that the TB group showed changes in the condylar region (right, P = .004; left, P = .022) compared to the control group.

CONCLUSION

Functional orthopaedic forces caused a decrease in the trabecular structure of the condylar area examined.

Measurement of the trabecular bone structure of the TMJ region in patients with transverse maxillary deficiency: a CBCT fractal analysis study

OBJECTIVE

This study aimed to evaluate the effect of transverse maxillary deficiency on condylar morphology via visual examination and fractal analysis of cone beam computed tomography (CBCT) scans.

STUDY DESIGN

In total, 97 patients with posterior crossbite or maxillary narrowness and 36 control patients were included. The presence of degenerative changes in the bilateral condyles was evaluated with CBCT. Fractal dimension (FD) was calculated on the condylar images using ImageJ.

RESULTS

Degenerative bone changes were discovered in 38 of the 133 scans (28.6%). There was no significant difference between the groups in terms of the incidence of degenerative changes for either the right or left sides (P ≥ .670). In coronal sections and in mean measurements, FD was significantly lower in the control group compared with the other groups in the right condyle (P ≤ .031). No significant differences were found between the mean FD values of the condyles with degenerative bone changes or the mean FD values of the normal condyles (P ≥ .256).

CONCLUSIONS

In the presence of maxillary transverse deficiencies, degenerative bone changes in the mandibular condyle were not significantly different, but the FD of the right condyle was found to be higher compared with the control group.

Two methods of evaluating mandibular trabecular pattern in intraoral radiographs and the association to fragility fractures during a 47-year follow up

In this longitudinal cohort study, we explored the association of fragility fractures to sparse trabecular bone pattern in intraoral radiographs using two methods, a visual and a semi-automated. Our aim was to study both sexes and to include younger age-groups, during a follow-up time of 47 years. The cohort consisted of 837 men and women aged 18-65 years, with intraoral radiographs from 1970-1971. The trabecular pattern was assessed in the mandibular premolar region with a visual and a semi-automated method. Data on fragility fractures were acquired from the Swedish National Patient Register for 47 years of follow-up time. Sparse trabecular pattern was found in 2.2% of the cohort using the visual method, and 18% were deemed at 'risk of osteoporosis' using the semi-automated method. A total of 132 individuals suffered at least one fragility fracture during the follow-up period. We found no significant association between fractures and sparse trabecular pattern using either method. This study shows that visual assessment, as a predictor of future fractures, may not be a suitable method for individuals of all ages and sexes. As for the semi-automated method, there is still very limited evidence for its fracture predictive ability.

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 and lacunarity analysis of mandibular bone on digital panoramic radiographs of tobacco users

Background. This study aimed to evaluate and compare changes in the mandibular trabecular bone pattern using the fractal dimension (FD) and lacunarity analysis in tobacco users with healthy controls.

Methods. This study was carried out on digital panoramic radiographs of 225 subjects divided into three groups: smokeless tobacco users (SLTs), smokers, and control (n=75). ImageJ program with FracLac plugin was used to assess the FD and lacunarity of mandibular trabecular bone on the digital panoramic radiographs.

Results. The differences in the mean FD values of the study and control groups were statistically significant (P < 0.001). Mean FD was lower in the case groups than the control group, with SLTs having the least FD value. A significant difference in lacunarity was noted between SLTs and controls (P < 0.001). On the contrary, there was no significant difference in lacunarity between smokers and controls.

Conclusions. FD values were lower in tobacco users, suggesting that tobacco users have a less complex trabecular bone pattern than healthy controls. Higher lacunarity values in SLTs indicated a more heterogeneous bone pattern. These findings signify that FD and lacunarity analysis on digital panoramic radiographs can serve as promising predictive tools to assess bone quality for osteoporotic changes in tobacco users, thereby facilitating prompt referral for further management.

Fractal analysis as a useful predictor for determining osseointegration of dental implant? A retrospective study

PURPOSE

The present study aimed at evaluating the effectiveness of fractal analysis on determining the osseointegration of dental implants.

MATERIAL AND METHODS

In a single center, retrospective clinical trial, patients with dental implants in the mandibular premolar/molar region, ASA I-II and < 65-year-old patients were included. Orthopantomograph (OPG) were taken before implant surgery (t0), within a week of surgery (t1), and 1 (t2) and 2 (t3) months after surgery, respectively. Three regions of interest (ROIs) from mesial, distal, and apical sites of the implants were chosen and fractal analysis (FA) was conducted with the box-counting algorithm using White and Rudolph's method.

RESULTS

A total of 39 patients 19 women and 20 men, with a mean age of 52.2 years (52.3 and 52.1 years, respectively) were included. The mean, minimum and maximum values of mesial (roi1), distal (roi2), and apical (roi3) surfaces were compared. The fractal dimension (FD) values of t1 were significantly lower compared with t0 as they decreased during the first week. FD values gradually increased after the first week although never exceeded the FD values of t0. Also, difference between mean FD values of t0 and t3 were found statistically significant (p < 0.05).

DISCUSSION

FA is a promising and noninvasive method to predict osseointegration of a dental implant based on dental radiographs, and it can help shorten the total treatment time.

From pixel to image analysis

Over the past 50 years, computer technology has evolved enormously. This has made it possible to carry out radiography in a completely new way, allowing to process X-ray images in an advanced manner and to extract the information from the image data. This article gives an overview of some of the most important developments in dental radiology. These include capturing the images, analysing and interpreting the image information and using the images for 3D reconstruction.

Changing trabecular patterns in panoramic radiographs of Swedish women during 25 years of follow-up

OBJECTIVES

The radiographic trabecular pattern on dental radiographs may be used to predict fractures. The aim of this study was to analyze longitudinal changes in the mandibles of 145 females between 1980 and 2005.

METHODS

Panoramic radiographs were obtained in 1980 and 2005. On 290 radiographs, regions of interest (ROIs) were selected in the ramus, angle and body. In all ROIs, the orientation was measured in 36 directions with the line frequency deviation method. The effects of ageing were analyzed for the fracture and the non-fracture groups separately.

RESULTS

During the follow-up, 61 females suffered fractures of the hip, wrist, spine, leg or arm. The fracture and non-fracture groups displayed dissimilar age changes in each investigated ROI. All significant changes pertained to increasing values of line frequency deviation. With increasing age, the trabecular network in the mandible lost details and the trabeculae became more aligned in their main direction. In the "ramus", the alignment was to the 110-120˚ axis, parallel to the posterior and anterior ramus border. In the "angle", the alignment was to the 135-150˚ axis, parallel to the oblique line, and in the "body" ROI to the 150-175˚ direction, approximately parallel to the occlusal plane and inferior cortex.

CONCLUSION

Most changes were consistent with the notion that the bone aged less severely in the non-fracture group. In the fracture group, the findings indicate that bone loss leads to redistribution of the remaining bone tissue in such a way that the trabeculae are accentuated perpendicular to the principal loading.

Increased Plasma Osteocalcin, Oral Disease, and Altered Mandibular Bone Density in Postmenopausal Women

An association between oral diseases and postmenopausal status has been recognized. However, the relationship between all oral disease, mandibular bone density, health status, and osteocalcin (OCN) bone markers in postmenopausal dental patients has not been reported. This study was therefore to verify the differences in plasma OCN levels, dental, periodontal, and oral mucosal disease, and mandibular bone density alterations from panoramic radiograph and systemic parameters in postmenopausal women, compared to premenopausal women. Oral, radiographic, and blood examination were performed in 92 females. Dental, periodontal, and oral mucosal statuses were recorded. Health profile parameters were collected from medical charts. Plasma OCN was evaluated by enzyme-linked immunosorbent assay. Forty-two (45.7%) participants were postmenopausal with a higher median age (55 (51, 62) years) than the premenopausal group (43 (38, 45) years). Overweight or obesity, hypercholesterolemia, and impaired fasting blood sugar were more prevalent in postmenopause. The average postmenopausal OCN level (425.62 ng/mL) was significantly higher than the premenopausal group (234.77 ng/mL, p < 0.001). The average number of missing teeth, mean attachment loss, alveolar bone loss, periapical lesion count, and clinical oral dryness score were also significantly higher in postmenopause (p=0.008,   < 0.001,  0.031,  0.006,  and 0.005, respectively). However, mandibular bone density determined by mandibular cortical index was lower in postmenopause (p < 0.001). The panoramic mandibular index, mandibular cortical width, fractal dimension, and other oral mucosal disease did not differ between the groups. Postmenopause was associated with elevated plasma OCN (β = 0.504, p < 0.001) when related covariates were adjusted. Elevated plasma OCN, oral mucosal dryness, high number of periapical radiolucencies and missing teeth, and lower mandibular bone density from panoramic radiograph were prevalent in postmenopausal women. Dentists should suspect an increased risk of low bone mineral density in postmenopausal patients who display these clinical and radiographic findings, and they should be referred for further examination. Plasma OCN may interconnect a relationship between postmenopausal status and the low mandibular 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.

Method for Automated Selection of the Trabecular Area in Digital Periapical Radiographic Images Using Morphological Operations

Objectives

The aim of this study is to propose a method that automatically select the trabecular bone area in digital periapical radiographic images using a sequence of morphological operations.

Methods

The study involved 50 digital periapical radiographic images of women aged from 36 to 58 years old. The proposed method consists of three stages: teeth detection, trabecular identification, and validation. A series of morphological operations—top-hat and bottom-hat filtering, automatic thresholding, closing, labeling, global thresholding, and image subtraction—are performed to automatically obtain the trabecular bone area in images. For validation, the results of the proposed method were compared with those of two dentists pixel by pixel. Three parameters were used in the validation: trabecular area, percentage of agreed area, and percentage of disagreed area.

Results

The proposed method obtains the trabecular bone area in a polygon. The obtained trabecular bone area is usually larger than that of previous studies, but is usually smaller than the dentists'. On average over all images, the trabecular area produced by the proposed method is 5.83% smaller than that identified by dentists. Furthermore, the average percentage of agreed area and the average percentage of disagreed area of the proposed method against the dentists' results were 75.22% and 8.75%, respectively.

Conclusions

The shape of the trabecular bone area produced by the proposed method is similar and closer to that identified by dentists. The method, which consists of only simple morphological operations on digital periapical radiographic images, can be considered for selecting the trabecular bone area automatically.

Comparison between fractal analysis and radiopacity evaluation as a tool for studying repair of an osseous defect in an animal model using biomaterials

OBJECTIVES

To evaluate bone repair of an osseous defect in a rat animal model through fractal analysis and radiopacity analysis in radiographic images.

METHODS

120 rats were subjected to extraction of their first molar and divided into four groups (n = 6/group) according to the material used for bone grafting: mineralized bovine bone, demineralized bovine bone (DBB), blood clot (BC - control) or Bio-Oss^® (BO). The animals were sacrificed after 1, 7, 14, 21 and 49 days and subjected to radiographic evaluation. For fractal analysis (FA), a square regionof interest of 30 × 30 pixels was used, and radiopacity was measured as the mean gray scale (MGS) value for three points of 5 × 5 pixels in the apical, medial and coronal regions of the defect. Histomorphometric evaluation was realized as the gold standard for bone neo-formation and maturation of the new osseous matrix.

RESULTS

Histomorphometric evaluation suggested that DBB showed faster mineralized deposition and resulted in more mature bone at the final time point of evaluation. Mineralized bovine bone and Bio-Oss presented similar results. The mineralized groups did not show significant differences in bone maturation. The radiopacity analysis revealed a significant difference (p < 0.05) between the DBB and blood clot groups at the final time point. FA did not show any significant differences at the final time point.

CONCLUSIONS

Mean gray scale seemed to be more effective for the quantification of bone repair than FA in the demineralized group in this animal model. Results for the mineralized groups did not reveal a significant difference, leading to the conclusion that both methods are effective.

Statistical Mechanics Involving Fractal Temperature

In this paper, the Schrödinger equation involving a fractal time derivative is solved and corresponding eigenvalues and eigenfunctions are given. A partition function for fractal eigenvalues is defined. For generalizing thermodynamics, fractal temperature is considered, and adapted equations are defined. As an application, we present fractal Dulong-Petit, Debye, and Einstein solid models and corresponding fractal heat capacity. Furthermore, the density of states for fractal spaces with fractional dimension is obtained. Graphs and examples are given to show details.

Relationship between Two Panoramic Radiography Indices and Bone Mineral Density of Postmenopausal Women with Osteopenia and Osteoporosis

STATEMENT OF THE PROBLEM

Reduced bone mineral density (BMD) generally affects postmenopausal women and it is classified into moderate (osteopenia) and significant osteoporosis. Based on digital panoramic radiographs (DPRs), several quantitative and qualitative assessment methods have been proposed for the diagnosis and evaluation of bone changes and as a predictor of BMD.

PURPOSE

The aim of this study was to compare mandibular cortical width (MCW) and mandibular cortical index (MCI) derived from DPRs in evaluating the BMD in osteopenic and osteoporotic post-menopausal women.

MATERIALS AND METHOD

In this cross-sectional study, the BMD assessment was performed using dual-energy X-ray absorptiometry (DEXA). Then, patients were divided into two groups: osteopenia and osteoporosis based on WHO criteria. Two types of T-scores including TT (trabecular) for lumbar spine, TC (cortical) for femoral neck and finally, MCW and MCI were measured based on DPRs.

RESULTS

Fifty females with the average age of 57.64±6.03 years were entered into the study. MCW significantly correlated with BMD (p< 0.05). Pearson correlation coefficient test revealed that there was almost significant relationship between MCI and BMD (p= 0.079). The area under the curve (AUC) in ROC suggested that there was a close overlap between MCW (0.773) and TC (0.783), but TT had the greatest AUC (0.996).

CONCLUSION

The results showed that MCW is an appropriate index of osteoporosis in post-menopausal women. Although the prediction of osteoporosis is poorer at the femoral neck than lumbar spine, MCW can serve as a screening tool for osteoporosis in this area.

Diffusion on Middle-ξ Cantor Sets

In this paper, we study Cζ-calculus on generalized Cantor sets, which have self-similar properties and fractional dimensions that exceed their topological dimensions. Functions with fractal support are not differentiable or integrable in terms of standard calculus, so we must involve local fractional derivatives. We have generalized the Cζ-calculus on the generalized Cantor sets known as middle-ξ Cantor sets. We have suggested a calculus on the middle-ξ Cantor sets for different values of ξ with 0<ξ<1. Differential equations on the middle-ξ Cantor sets have been solved, and we have presented the results using illustrative examples. The conditions for super-, normal, and sub-diffusion on fractal sets are given.

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.

Evaluation of trabecular pattern of mandible using fractal dimension, bone area fraction, and gray scale value: comparison of cone-beam computed tomography and panoramic radiography

OBJECTIVE

This study was performed to compare the fractal dimension (FD), bone area fraction (BAF), and gray scale value (GSV) on digital panoramic radiography (DPR) and cross-sectional cone-beam computed tomography (CBCT) using image analysis and to determine whether a relationship exists among parameters associated with bone quality.

METHODS

Thirty edentulous human hemimandibles were scanned by DPR and CBCT. Ninety regions of interest (ROIs) were evaluated on DPR and CBCT images to calculate the FD and BAF. The GSV of the ROI on CBCT was also calculated.

RESULTS

Statistically significant differences were observed in the FD values of the ROIs between DPR and CBCT (p = 0.002) and in the BAF values of ROIs between DPR and CBCT (p = 0.017). The Spearman's correlation test revealed a statistically significant high correlation between the FD and BAF values of the ROIs on DPR and between the FD and BAF values of the ROIs on CBCT (p < 0.01). No significant correlations were observed between the GSVs of ROIs on CBCT and the FD values of ROIs on DPR, the BAF values of ROIs on DPR, the FD values of ROIs on CBCT, and the BAF values of ROIs on CBCT (p > 0.05).

CONCLUSIONS

The GSV did not support the FD and BAF. Additionally, DPR and CBCT did not have similar image quality for assessing the FD, BAF, and GSV. In evaluating the trabecular structure, the use of panoramic radiographs should be continued because the image resolution of CBCT is lower and its generalized dose is higher than that of panoramic radiography. These results may serve as a reference for clinical practitioners using dental CBCT to analyze the trabecular structures of alveolar bones.

Strut analysis for osteoporosis detection model using dental panoramic radiography

OBJECTIVES

The aim of this study was to identify variables that can be used for osteoporosis detection using strut analysis, fractal dimension (FD) and the gray level co-occurrence matrix (GLCM) using multiple regions of interest and to develop an osteoporosis detection model based on panoramic radiography.

METHODS

A total of 454 panoramic radiographs from oral examinations in our dental hospital from 2012 to 2015 were randomly selected, equally distributed among osteoporotic and non-osteoporotic patients (n = 227 in each group). The radiographs were classified by bone mineral density (T-score). After 3 marrow regions and the endosteal margin area were selected, strut features, FD and GLCM were analysed using a customized image processing program. Image upsampling was used to obtain the optimal binarization for calculating strut features and FD. The independent-samples t-test was used to assess statistical differences between the 2 groups. A decision tree and support vector machine were used to create and verify an osteoporosis detection model.

RESULTS

The endosteal margin area showed statistically significant differences in FD, GLCM and strut variables between the osteoporotic and non-osteoporotic patients, whereas the medullary portions showed few distinguishing features. The sensitivity, specificity, and accuracy of the strut variables in the endosteal margin area were 97.1%, 95.7 and 96.25 using the decision tree and 97.2%, 97.1 and 96.9% using support vector machine, and these were the best results obtained among the 3 methods. Strut variables with FD and/or GLCM did not increase the diagnostic accuracy.

CONCLUSION

The analysis of strut features in the endosteal margin area showed potential for the development of an osteoporosis detection model based on panoramic radiography.

Fractal analysis of subchondral bone changes of the hand in rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic and systemic inflammatory disorder. Conventional radiography, a widely available and cost-effective examination method, remains the standard of reference for the detection and quantification of joint involvement in RA. Fractal dimension (FD) of the trabecular bone structure has been proven to correlate with the bone's physical properties. The present study was designed to use fractal analysis to validate radiograph changes in the hand of RA patients.This study retrospectively evaluated the hand radiographs of 108 subjects. Fifty-four patients were suffering from RA, of which 18 were men and 36 were women. Their ages ranged from 25 to 90 years. The hand radiographs of 54 healthy patients, 18 men and 36 women (age range 23-88 years), were used as the control group. Bone structure value (BSV) is a critical parameter for the assessment and analysis of bone microarchitecture. The BSVs were calculated over the fractal dimension using the Brownian motion.The BSV calculated for ROI showed a significant difference in ROI5 (0.210 ± 0.045), ROI6 (0.186 ± 0.066), and ROI11 (0.201 ± 0.056) in patients with RA, in comparison to the CG (P < 0.05). A significant correlation was observed between anti-CCP and ROI4, ROI5, ROI6, ROI9, and ROI12 in seropositive RA patients (post hoc test (Bonferroni) P <0.001).This study demonstrates that the bone textural image analysis technique can be used to quantify the radiographic changes in RA hands, based on comparisons of FDs.

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.

Effect of two jumping programs on hip bone mineral density in premenopausal women: a randomized controlled trial

PURPOSE

To determine the effect of two jumping programs on hip bone mineral density (BMD) in women.

DESIGN

Randomized controlled trial.

SETTING

Approximately 20 cities in the Mountain West.

SUBJECTS

Sixty premenopausal women, aged 25 to 50 years, completed the intervention.

INTERVENTION

Subjects were randomly assigned to a control group or one of two jumping groups. The Jump 10 group performed 10 jumps with 30 seconds rest between jumps, twice daily for 16 weeks, while the Jump 20 group performed the same protocol but with 20 jumps.

MEASURES

Hip BMD was measured by using dual-energy x-ray absorptiometry.

ANALYSIS

Analysis of variance and covariance.

RESULTS

At 8 weeks, unadjusted percentage change in hip BMD was significantly different among groups (F = 5.4, p = .0236). Specifically, compared with controls, the Jump 20 women had significantly greater gains in hip BMD and the Jump 10 women had marginally greater improvements. Following 16 weeks of jumping, differences between the Jump 10 and the Jump 20 groups compared with controls were significant (F = 4.2, p = .0444), especially after adjusting for the covariates (F = 7.3, p = .0092).

CONCLUSION

After 16 weeks of high-impact jump training, hip BMD can be improved in premenopausal women by jumping 10 or 20 times, twice daily, with 30 seconds of rest between each jump, compared with controls.

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.

Prevalence and Risk Factors of Osteoporosis in Women Referring to the Bone Densitometry Academic Center in Urmia, Iran

BACKGROUND

Osteoporosis is one of the fastest growing health problems around the world. Several factors can affect this silent disease. The current study aimed to determine the prevalence and risk factors of osteoporosis in women in Urmia, a city in northwestern Iran.

METHODS

This cross‑sectional study was performed on 360 non-pregnant women over the age of 15 who referred for bone density testing to the Urmia Imam Khomeini Academic Hospital. Data were collected by questionnaire, and bone mineral density of the femoral neck and lumbar spines L1- L4 was evaluated by dual X-ray absorptiometry.

RESULTS

The total prevalence of osteoporosis in this study was 42.2%; prevalence of osteoporosis among women 45 years old or less was 14.3% and over the age of 45 years was 50.7%. The factors such as level of education, history of bone fracture, disease history (rheumatoid arthritis, diabetes, high blood pressure), gravidity and parity values, duration of lactation (p<0.001), nutrition dimension of lifestyle (p=0.03), and green tea consumption (p=002) showed a statistically significant association with the bone mineral density. According to the regression model, age (OR=1.081), history of bone fracture (OR=2.75), and gravidity (OR=1.14) were identified as significant risk factors for osteoporosis, while the body mass index (OR=0.94) was identified as a protector against osteoporosis.

CONCLUSION

The prevalence of osteoporosis in this study was high, and findings showed that the advancement of age, lifestyle, and reproductive factors (especially gravidity and duration of lactation) were determining factors for osteoporosis .Appropriate educational programs and interventions could help to increase the women's peak bone mass therefore reducing their risk of developing osteoporosis.

Cardiorespiratory Fitness and Hip Bone Mineral Density in Women: A 6-Year Prospective Study

Cross-sectional studies and short term interventions focusing on fitness and bone mineral density (BMD) are common. However, few investigations have studied the effect of fitness on BMD over an extended period of time. The present study was conducted to determine the extent to which cardiorespiratory fitness influences risk of BMD loss at the hip over 6 yr. A prospective cohort design was used with 245 healthy, middle-aged women. Hip BMD was assessed using dual energy x-ray absorptiometry. Calcium and vitamin D were measured using the Block Food Frequency Questionnaire. Menopause status was measured by a questionnaire. Results showed that fit and unfit women experienced similar changes in hip BMD over time. Specifically, unfit women experienced a non-significant 7% increased risk of losing hip BMD compared to their counterparts (RR = 1.07, 95% CI = 0.66, 1.73). Adjusting statistically for differences in age, initial body weight, and hip BMD, weight change, menopause status, calcium and vitamin D intake, and time between assessments had little effect on the relationship. Fitness level did not influence risk of hip BMD loss over time.

The three-dimensional microstructure of trabecular bone: Analysis of site-specific variation in the human jaw bone

Purpose

This study was performed to analyze human maxillary and mandibular trabecular bone using the data acquired from micro-computed tomography (micro-CT), and to characterize the site-specific microstructures of trabeculae.

Materials and Methods

Sixty-nine cylindrical bone specimens were prepared from the mandible and maxilla. They were divided into 5 groups by region: the anterior maxilla, posterior maxilla, anterior mandible, posterior mandible, and mandibular condyle. After the specimens were scanned using a micro-CT system, three-dimensional microstructural parameters such as the percent bone volume, bone specific surface, trabecular thickness, trabecular separation, trabecular number, structure model index, and degrees of anisotropy were analyzed.

Results

Among the regions other than the condylar area, the anterior mandibular region showed the highest trabecular thickness and the lowest value for the bone specific surface. On the other hand, the posterior maxilla region showed the lowest trabecular thickness and the highest value for the bone specific surface. The degree of anisotropy was lowest at the anterior mandible. The condyle showed thinner trabeculae with a more anisotropic arrangement than the other mandibular regions.

Conclusion

There were microstructural differences between the regions of the maxilla and mandible. These results suggested that different mechanisms of external force might exist at each site.