Relationship of mandibular and cervical vertebral bone density using computed tomography

Opportunistic measures of bone mineral density at multiple skeletal sites during whole-body CT in polytrauma patients

Whole-body CT in polytrauma patients revealed bone mineral density variations throughout the skeleton. Bone density was the highest in cranial bones and the lowest in proximal extremities and pelvis. Skeletal age-related changes were generally more pronounced than sex-related changes. Cranial bones did not follow the same aging pattern compared to other bones.

INTRODUCTION

Whole-body CT (WBCT) in polytrauma patients enables the detection of numerous incidental findings, such as estimates of bone mineral density (BMD) at multiple skeletal sites. This could help in better understanding of age- and sex-related changes in BMD through skeleton.

METHODS

Data were retrospectively retrieved from the WBCTs requested during a 2-year period. BMD, expressed in CT Hounsfield units (HU), was measured at frontal and occipital bone, four vertebrae (C4, Th7, L4, and S2), iliac bone, and proximal humerus and femur. Measurements were done on native and postcontrast scans. The population sample was age-, sex-, and visceral fat volume adjusted for analysis.

RESULTS

A total of 296 patients were included, with a median age of 51 years. BMD varied from the highest HU in cranial bones (629 HU) to the lowest HU in the pelvic bones (114 HU), P < 0.001. Sex differences were independent predictors of BMD in cranial bones and proximal humerus. The age-related decline in BMD was significant in all other bones, but the association with age differed among the measurement's sites. Visceral fat showed the strongest correlation with the lumbar spine and iliac wing, although multivariate analysis revealed it was not an independent predictor of bone density, such as age and sex.

CONCLUSIONS

BMD varies through skeleton, being the highest in the proximal axial skeleton. Age-related changes in BMD are significant and more pronounced than sex-related changes in almost all bones. Cranial bones do not follow the same pattern compared to other bones.

The Use of Dual Energy X-Ray Bone Density Scan in Assessment of Alveolar Cleft Grafting Using Bone Marrow Stem Cells Concentrate/Platelet-Rich Fibrin Regenerative Technique

OBJECTIVES

To determine the densitometric quality of regenerated bone at the site of bone marrow and platelet-rich membrane grafting technique at unilateral alveolar cleft region using dual energy x-ray bone density scan (DEXA).

METHODS

The present prospective cohort study included 16 unilateral alveolar cleft patients who were selected randomly from the outpatient maxillofacial surgery clinic and suffered from unilateral alveolar cleft. Bone marrow aspirate and platelet-rich fibrin (PRF) (bone marrow stem cells + PRF) were used as the grafting material. Six months of follow-up have been conducted for all patients' including clinical and radiographic assessments with (DEXA scan).

RESULTS

Sixteen unilateral patients with a mean age of 12.56 ± 1.71 years were included in the sample and the majority of patients were females with a frequency of 56.2 percent. The current research revealed no infection or wound dehiscence. After surgery, the pain and edema scores were reasonable. Our findings showed that, after 6 months of regenerative graft, the average bone mineral density of the cleft side DEXA scan value was 1.56 ± 0.32 gm/cm2, compared to 1.51 ± 0.488 gm/cm2 on the normal side of the noncleft scan. There was no statistically significant difference in DEXA bone mineral content measurements between the cleft and standard sides (P = 0.461).

CONCLUSIONS

The bone marrow stem cells + PRF regenerative graft technique has been successfully integrated, and the DEXA scan approach for measuring regenerated grafted bone mineral content was found to be appropriate for simple and inexpensive follow-up of alveolar cleft lip patients.

Correlation of Radiomorphometric Indices of the Mandible and Biochemical Parameters in Patients with Secondary Hyperparathyroidism Due to Chronic Kidney Disease

OBJECTIVE

 The aim was to correlate radiomorphometric indices and biochemical analyses as an auxiliary method in bone evaluation in male and female patients with chronic kidney disease-mineral and bone disorder (CKD-MBD) and controls.

MATERIALS AND METHODS

 Nine radiomorphometric indices and four biochemical parameters were obtained: mental index (MI), height at the mental foramen, total mandibular height (THM), panoramic mandibular index (PMI), original height of the mandible, alveolar bone resorption, distance from the mental foramen to the alveolar bone crest (MF-ABC), mandibular cortical index (MCI), trabecular bone pattern, parathyroid hormone (PTH), calcium (Ca), phosphorus (P), and Ca × P product (Ca × P).

STATISTICAL ANALYSIS

 The Mann-Whitney U-test, chi-squared test, and Spearman's correlation were applied at a significance level of 95%.

RESULTS

 There was a moderate negative and significant correlation between MI, PMI, and PTH in female patients with CKD-MBD as well as between THM, MF-ABC, and Ca × P. The MCI and trabecular bone pattern indicated altered bone quality in male patients.

CONCLUSIONS

 The radiomorphometric evaluation was an auxiliary, noninvasive method to detect possible alterations in the cortex and mandibular bone trabeculation in male and female patients with CKD-MBD.

Decrease in Mandibular Cortical in Patients With Type 1 Diabetes Mellitus Combined with Poor Glycemic Control

In this study we analyzed the mandibular cortical bone of patients with type 1 diabetes mellitus (T1DM) and non-diabetic. Fifty patients with T1DM and 100 non-diabetic ones paired by age and gender were analyzed. Two double-blinded observers evaluated 150 digital panoramic images of both groups. The mandibular cortical bone was analyzed using the Mandibular Cortical Index (MCI), Mental Index (MI), Gonial Index (GI), Antegonial Index (AI) and Upper and Lower Panoramic Mandibular Indexes (UPMI and LPMI), with the aid of RADIOIMP® software. Influence of T1DM in the morphology of the mandibular cortical bone was studied based on obtaining data related to T1DM diagnosis time, blood glucose level, T1DM control and the presence of chronic complications. Collected data were submitted to descriptive (mean and standard deviation) and inferential analyzes (Pearson's chi-squared test and Fisher's exact test) (p≤0.05). According to the MCI, individuals with T1DM had higher frequencies of mandibular cortical alterations, in both sexes and all age groups (p<0.01). For quantitative indexes, MI, GI, AI, UPMI and LPMI, female patients showed statistically significant differences for GI and AI, while male patients had statistically significant differences for all indexes (p<0.05), presenting the individuals with TDM1 inferior measures. Individuals with poor T1DM control showed significantly higher frequency of mandibular cortical alteration (92.3%), with lower means for MI, GI, AI and LPMI (p≤0.05). In conclusion, patients with T1DM showed decrease in the mandibular cortical bone when compared to non-diabetic ones, indicating that poor disease control is associated with these alterations.

Efficacy of Cone-Beam Computed Tomography in Evaluating Bone Quality for Optimum Implant Treatment Planning

PURPOSE

This study examined (1) if cone-beam computed tomography (CBCT) can determine relative differences in bone mineral density distribution using clinical images of patients' mandibular bone and (2) if the relative differences can be used to detect the effects of sex and age on bone mineral density distribution.

MATERIALS AND METHODS

Sixty-six clinical CBCT images from patients (36 females and 30 males) of 3 age groups (40, 50, and 60 years) were identified. Alveolar (AB) and basal cortical bone (CB) regions were digitally isolated. A histogram of gray levels, which are proportional to degrees of bone mineralization, was obtained from each region. Mean, variability (SD and coefficient of variation), and percentage differences of gray level parameters between AB and basal CBs were computed.

RESULTS

Significant sex differences in gray level variability were observed within the postmenopausal age group (P < 0.042).

CONCLUSION

These findings suggest that clinical CBCT images can be a valuable tool in providing information on bone quality, which is an important criterion for optimum planning for dental implant placement.

Can gray values derived from CT and cone beam CT estimate new bone formation? An in vivo study

OBJECTIVES

The main aim of this study was to investigate whether Hounsfield unit derived from computed tomography (HU/CT) and gray value derived from cone beam computed tomography (GV/CBCT) can predict the amount of new bone formation (NBF) in the defects after bone reconstruction surgeries.

MATERIALS AND METHODS

Thirty calvaria defects created in 5 rabbits and grafted with both radiolucent (RL, n = 15) and radiopaque (RO, n = 15) bone substitute materials were evaluated, 8 weeks postoperatively. The defects were scanned by multislice computed tomography (Somatom®, Siemens Healthineers, Erlangen, Germany) and CBCT (NewTom VG®, Qualitative Radiology, Verona, Italy). MSCT and CBCT scans were matched to select the exact region of interest (ROI, diameter = 5 mm and height = 1 mm). HU/CT and GV/CBCT of each ROI were obtained. Mean amount of NBF in whole of the defects was measured using serial histomorphometric assessment. We investigated the correlation between HU/CT and GV/CBCT, HU/CT and NBF, and GV/CBCT and NBF generally, and separately among the RL or RO grafted defects, by linear generalized estimating equation modeling. Receiver operation characteristic analysis was performed to check the accuracy of HU/CT and GV/CBCT in diagnosing more than 10% NBF in the samples.

RESULTS

There were linear correlations between HU/CT and GV/CBCT, HU/CT and NBF, and GV/CBCT and NBF.

CONCLUSION

According to the results, both HU/CT and GV/CBCT can be considered as fairly good predictors for assessment of the amount of NBF following bone reconstruction surgeries.

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.

Accuracy of Quantitative Computed Tomography Bone Mineral Density Measurements in Mandibles: A Cadaveric Study

PURPOSE

The aim was to investigate the accuracy of quantitative computed tomography bone mineral density (BMD) measurements in mandibles, comparing measured BMD with calibrated BMD.

MATERIALS AND METHODS

Seventy mandibles from adult cadavers were used. Twenty tomographic cuts were made in each mandible. In each tomographic cut, a region of interest was located, and the bone density was measured in Hounsfield unit (HU). A polymethyl methacrylate phantom containing four inserts of different predetermined densities (hydroxyapatite 100, 200, 500, and 700 mg/cm(3) ) was used to calculate calibrated bone density. Correlation between measured and calibrated bone densities was calculated.

RESULTS

Mean total correlation between measured and calibrated BMD in the 20 sagittal tomography cuts showed almost perfect positive correlation (r = 0.998, p < .001). However, when average BMD measurements in HU were compared, the measured total BMD (in the 20 sagittal tomography cuts studied) was 54.99 ± 421.59, whereas the total calibrated BMD was 49.28 ± 364.95, with statistically significant difference (p = .001).

CONCLUSIONS

There are discrepancies between measured and calibrated BMD; in this sense, a calibrated bone phantom with a predetermined mineral density should be used to determine the exact BMD before dental implants surgery.

Is there correlation between alveolar and systemic bone density?

OBJECTIVE: The present study assessed the correlation between maxillomandibular alveolar bone density and systemic bone mineral density (BMD). METHODS: Dual-energy X-ray absorptiometry of the anterior and posterior maxillomandibular alveolar bone, of the standard sites for the measurement of BMD (lumbar spine and femur) and the third cervical vertebra was performed on 23 middle-aged women. Periapical radiographs were also obtained, with an aluminum step-wedge as reference for the digital reading of apical bone density of the upper incisors. RESULTS: Spearman's correlations coefficients revealed that density in the apical region was correlated with that of the femoral neck (r = 0.433; p < 0.05); BMDs of the posterior regions of the mandible and maxilla were significantly correlated with that of the cervical vertebra (r = 0.554, p < 0.01 and r = 0.423, p < 0.05, respectively); and the anterior maxilla was correlated with the posterior mandible (r = 0.488, p < 0.05). CONCLUSION: Bone density of the maxillary alveolar bone was significantly correlated with that of the femoral neck. Among the bone densities of the alveolar regions, only the anterior maxilla and the posterior mandible were significantly correlated. The findings suggested that bone densitometry might be individually and locally evaluated.

Evaluation of bone alterations in the jaws of HIV-infected menopausal women

The advent of highly active antiretroviral therapy (HAART) has caused a reduction in mortality, thus contributing to an increase in the number of women with HIVࢧAIDS who reach the climacteric period, experience decline in ovarian function, and develop complications of viral infection and HAART, which can accelerate bone loss. The aim of this study was to detect possible alterations in the jaws of HIV-infected women by panoramic radiography. The study comprised a total of 120 women above 40 years of age who were divided into the following two groups: women who are HIV positive (Group I) and women with no known HIV infection (Group II). Measurement of the following three radiomorphometric indexes was performed by panoramic radiography: Mental Index (MI), Panoramic Mandibular Index (PMI) and Antegonial Depth (AD). A total of 70% of women in the control group and 50% of women in the HIV group were in the postmenopausal period, and the average values of both MI (p = 0.0054) and AD (p < 0.0001) for this period were lower in the HIV group than in the control group. For patients who were in the premenopausal period, the average AD was lower in the HIV group than in the control group (p = 0.0003). Despite the difference in the average age between groups, greater bone resorption in the mandible was found in the group of HIV-positive women.

Osteoporosis, jawbones and periodontal disease

The association between osteoporosis and jawbones remains an argument of debate. Both osteoporosis and periodontal diseases are bone resorptive diseases; it has been hypothesized that osteoporosis could be a risk factor for the progression of periodontal disease and vice versa. Hypothetical models linking the two conditions exist: in particular, it is supposed that the osteoporosis-related bone mass density reduction may accelerate alveolar bone resorption caused by periodontitis, resulting in a facilitated periodontal bacteria invasion. Invading bacteria, in turn, may alter the normal homeostasis of bone tissue, increasing osteoclastic activity and reducing local and systemic bone density by both direct effects (release of toxins) and/or indirect mechanisms (release of inflammatory mediators). Current evidence provides conflicting results due to potential biases related to study design, samples size and endpoints. The aim of this article is to review and summarize the published literature on the associations between osteoporosis and different oral conditions such as bone loss in the jaws, periodontal diseases, and tooth loss. Further well-controlled studies are needed to better elucidate the inter-relationship between systemic and oral bone loss and to clarify whether dentists could usefully provide early warning for osteoporosis risk.

Residual ridge atrophy in complete denture wearers and relationship with densitometric values of a cervical spine: a hierarchical regression analysis

BACKGROUND

The rate of residual ridge atrophy (RRR) and its association with mineral density of other bones have not yet been fully explained.

OBJECTIVE

To measure RRR over a 5-year period in complete denture wearers and relate it to the density of a cervical spine (CSBD).

MATERIALS AND METHODS

Sixty-two patients (different gender, age, body mass index, duration of edentulousness (DE) and different denture-wearing habits) participated. A copper stepwedge was attached to the cassette, and 50 lateral radiograms met the criteria to be included.

RESULTS

A significant decrease in vertical height was observed in all measured sites. The amount of RRR was highest in frontal areas of both jaws and decreased gradually towards lateral regions. Hierarchical regression analysis revealed that the amount of RRR in the maxillary frontal area could be explained up to 48.4% by the variable DE and only up to 6.1% by the CSBD, while gender had almost no influence (1%). Similar results were obtained for the lateral maxillary RRR (33.9%; 7%; 2%), frontal mandibular RRR (40; 8.4; 0.4%) and lateral mandibular RRR (31.5%; 3.4%; 7.7%).

CONCLUSION

Skeletal bone density, reflecting systemic and hereditary factors, is weakly related to RRR (3.4-8.4%).

Osteoporosis, the risk of vertebral fracture, and periodontal disease in an elderly group in Mexico City

OBJECTIVES

The aims of this study were to identify the possible association of osteoporosis, fracture risk and periodontitis, and consider the role of pharmacological treatment of osteoporosis and the periodontal condition.

METHODS

Patients aged 60 and older from the Mexican National Medical Science and Nutrition Institute Salvador Zubirán participated in the study. DXA was used to assess osteoporosis and risk of vertebral fracture. A modified version of the extent and severity index (ESI) was applied to evaluate periodontitis (cut-off point for attachment loss ≥ 4 mm) and all teeth were examined.

RESULTS

One hundred and sixty-six patients were examined, 88.6% were females, 47.0% had osteoporosis and 38.6% showed a high risk of fracture. The modified ESI was 5.13 mm (SD 1.4), 57.8% (SD 29.7). The model for periodontitis severity showed an association with oral hygiene (OR = 1.85) and use of osteoporosis medication (OR = 0.43). The model for the extent of periodontitis identified an association with smoking (OR = 2.37), osteoporosis (OR = 1.82) and osteoporosis medication (OR = 0.36). The model for tooth loss detected an association with fracture risk (OR = 3.02) and osteoporosis medication (OR = 0.33).

CONCLUSION

Periodontitis extent was associated with osteoporosis, and tooth loss with fracture risk.

Assessment of bone mineral density in the jaws and its relationship to radiomorphometric indices

OBJECTIVES

The aim of this study was to evaluate maxillary, mandibular and femoral neck bone mineral density using dual energy X-ray absorptiometry (DXA) and to determine any correlation between the bone mineral density of the jaws and panoramic radiomorphometric indices.

METHODS

49 edentulous patients (18 males and 31 females) aged between 41 and 78 years (mean age 60.2 +/- 11.04) were examined by panoramic radiography. Bone mineral density (BMD) of the jaws and femoral neck was measured with a DXA; bone mineral density was calculated at the anterior, premolar and molar regions of the maxilla and mandible.

RESULTS

The mean maxillary molar BMD (0.45 g cm(-2)) was significantly greater than the maxillary anterior and premolar BMD (0.31 g cm(-2), P < 0.05). Furthermore, the mean mandibular anterior and premolar BMD (1.39 g cm(-2) and 1.28 g cm(-2), respectively) was significantly greater than the mean mandibular molar BMD (1.09 g cm(-2), P < 0.01). Although BMD in the maxillary anterior and premolar regions were correlated, BMD in all the mandibular regions were highly correlated. Maxillary and mandibular BMD were not correlated with femoral BMD. In addition, mandibular cortical index (MCI) classification, mental index (MI) or panoramic mandibular index (PMI) values were not significantly correlated with the maxillary and mandibular BMDs (P > 0.05).

CONCLUSIONS

The BMD in this study was highest in the mandibular anterior region and lowest in the maxillary anterior and premolar regions. The BMD of the jaws was not correlated with either femoral BMD or panoramic radiomorphometric indices.

Evaluation by quantitative magnetic resonance imaging of trabecular bone quality in mandible and cervical vertebrae

OBJECTIVE

The purpose of this study was to make a comparison between mandibular and cervical vertebral bone quality (BQ) using quantitative magnetic resonance imaging (MRI).

METHODS

The cervical MRI images included in this study belonged to 36 patients (23 women, 13 men; mean age 54 years) who had various clinical symptoms (e.g., headache, vertigo, imbalance). The mandible and cervical vertebrae BQ measurements were performed by the same investigator on these sections. Mandibular and cervical vertebral T2(*) axial cross sections were performed following receipt of consent from each patient. T2(*) relaxation time values were determined in the trabecular area.

RESULTS

The relationship between cervical vertebral and mandibular BQ was revealed by regression and correlation analysis. The correlation coefficient was r=0.04, r(2)=0.002, and P=0.818, which is not statistically significant. The relation between age and mandible BQ was very weak (r=0.001, r(2)=0.000001, and P=0.995), and the relation between age and cervical vertebrae BQ was correlated (r=-0.585, r(2)=0.342, and P<0.001).

CONCLUSIONS

There is a low correlation between the BQ measurements of cervical vertebrae and the mandible. Precise mandibular BQ measurement does not provide information that correlates with BQ in the other sites of the skeleton. Although an age-dependent decrease occurs in vertebral BQ, no significant alteration occurs in mandibular BQ.