Relationship between dental panoramic radiographic findings and biochemical markers of bone turnover

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.

Radiographical Diagnostic Evaluation of Mandibular Cortical Index Classification and Mandibular Cortical Width in Female Patients Prescribed Antiosteoporosis Medication: A Retrospective Cohort Study

Osteoporosis is often detected late and becomes severe because of a lack of subjective symptoms. Digital panoramic radiography (DPR) has been reported to be useful for osteoporosis screening based on the morphological classification of the mandibular inferior cortex. The purpose of this study was to evaluate the sensitivity and specificity of the mandibular cortical index (MCI) in the diagnosis of osteoporosis in a group of patients who were and were not using antiosteoporosis medication (AOM). Three hundred and fifty female patients aged 40 years or older who had DPR imaging performed during a 6-year period from December 2015 to February 2022 met the selection criteria. Two examiners recorded mandibular cortical width and MCI from the images. These results were statistically examined together with the patients' demographic data. Forty-nine patients were using AOM (13 nonbisphosphonate/denosumab and 36 bisphosphonate/denosumab). MCI type 3 was the most common in the AOM group. In the MCI classification, DPR imaging among the AOM group was more sensitive (0.95) than that of the control group. This method of estimating osteoporosis based on MCI classification using DPR images has high sensitivity, especially in patients using AOM, suggesting that this method is useful as a screening test.

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.

Bone mineral density and muscle mass in adults with developmental skeletal discrepancies

Background

It was aimed to investigate the musculoskeletal status in individuals diagnosed with skeletal discrepancies.

Methods

This case–control study was performed on 35 patients with developmental skeletal discrepancies listed for orthognathic surgery as a case group and 33 patients who were nominated for wisdom tooth removal as a control group. All participants were aged 18–40 years and the research was carried out in the period between May 2018 and May 2019. Dual X-ray absorptiometry (DEXA) was used to assess bone mass density at three bone sites: total hip, femoral neck, and the spinal lumbar vertebrae (L1-L4). The appendicular muscle mass index (ASMI) was measured based on the four limbs from the DEXA scan.

Results

Our data showed that 45.7% (16) of the case group were osteopenic or osteoporotic while in the control group only 21.2% (7) were osteopenic in at least one region (total hip, femoral neck, or lumbar) (p-value = 0.03).

Regarding muscle mass, there was significantly lower SMI in subjects with skeletal discrepancies (case group) compared with the control group (median (IQR) 5.9 (2.5) vs. 6.8 (2.9) (kg/m2), respectively, p = 0.04).

Conclusions

There is an essential need for more studies to understand the exact interrelationship between musculoskeletal status and skeletal jaw discrepancies.

Identification of osteoporosis using ensemble deep learning model with panoramic radiographs and clinical covariates

Osteoporosis is becoming a global health issue due to increased life expectancy. However, it is difficult to detect in its early stages owing to a lack of discernible symptoms. Hence, screening for osteoporosis with widely used dental panoramic radiographs would be very cost-effective and useful. In this study, we investigate the use of deep learning to classify osteoporosis from dental panoramic radiographs. In addition, the effect of adding clinical covariate data to the radiographic images on the identification performance was assessed. For objective labeling, a dataset containing 778 images was collected from patients who underwent both skeletal-bone-mineral density measurement and dental panoramic radiography at a single general hospital between 2014 and 2020. Osteoporosis was assessed from the dental panoramic radiographs using convolutional neural network (CNN) models, including EfficientNet-b0, -b3, and -b7 and ResNet-18, -50, and -152. An ensemble model was also constructed with clinical covariates added to each CNN. The ensemble model exhibited improved performance on all metrics for all CNNs, especially accuracy and AUC. The results show that deep learning using CNN can accurately classify osteoporosis from dental panoramic radiographs. Furthermore, it was shown that the accuracy can be improved using an ensemble model with patient covariates.

Assessment of bone metabolism biomarkers in serum and saliva of cirrhotic patients

OBJECTIVE

To assess the serum and salivary levels of biomarkers related to bone metabolism in cirrhotic patients as well as the evidence of osteoporotic changes on panoramic radiographs.

MATERIALS AND METHODS

Thirty-eight cirrhotic patients underwent anamnesis and physical examination. Specimens of blood and saliva were collected for evaluation by using Luminex™ xMAP technology to quantify RANKL, OPG, IL-1β, IL-6 and TNF-α. Panoramic radiographs were evaluated based on the mandibular cortical index (MCI) and the resulting data were compared to the expression of biomarkers in serum and saliva. Descriptive data analysis was performed and the Mann-Whitney's test and Spearman's correlation were used.

RESULTS

Most of the sample consisted of males (68.4%) who had cirrhosis mostly resulting from alcoholism (28.9%). Median concentration values of RANKL (74.44 pg/mL), IL-1 β (45.91 pg/mL), IL-6 (67.69 pg/mL) and TNF-α (5.97 pg/mL) in saliva were higher than those observed in serum. In 72.7% of the panoramic radiographs, MCI was found to be suggestive of osteoporotic changes. No statistically significant correlation was observed between salivary and serum expressions of biomarkers or between biomarkers and MCI.

CONCLUSION

RANKL, OPG, IL-1β, IL-6 and TNF-α are expressed differently in serum and saliva and the concentration of these biomarkers is not related to MCI.

CLINICAL RELEVANCE

This study contributes to the study of the mechanisms of osteoporosis in cirrhotic individuals.

Repercussions of osteoporosis on the maxillofacial complex: a critical overview

INTRODUCTION

We present here a literature review focusing on the repercussions of osteoporosis on the oral and maxillofacial complex. Osteoporosis is a silent metabolic disorder characterized by reduced bone mineral density (BMD), which can lead to bone fractures, particularly affecting elderly women. The prevalence of this disease has increased significantly worldwide, and since it accelerates bone resorption also in the jaw bones, some attention has been paid to possible oral and maxillofacial manifestations.

MATERIALS AND METHODS

The databases PubMed and Google Scholar were searched for reports of oral and maxillofacial changes related to osteoporosis.

RESULTS

Several parameters evaluating bone changes in panoramic radiography have been proposed to estimate osteoporosis-related BMD loss, but they tend to warn about the possibility of osteoporosis, rather than being diagnostic criteria. Meanwhile, it seems that osteoporosis-related BMD loss could delay alveolar bone healing and potentiate bone loss in periodontal disease.

CONCLUSION

Even though orofacial bones are not compromised by osteoporosis as much as the axial/appendicular skeleton, a regular dental follow-up of osteoporotic patients is advised, especially in the case of periodontal disease and maxillofacial surgery. Further controlled longitudinal studies considering the site-specificity of osteogenesis would be helpful regarding this issue.

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

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

Respective role of membrane and nuclear estrogen receptor (ER) α in the mandible of growing mice: Implications for ERα modulation

Estrogens play an important role in bone growth and maturation as well as in the regulation of bone turnover in adults. Although the effects of 17β-estradiol (E2) are well documented in long bones and vertebrae, little is known regarding its action in the mandible. E2 actions could be mediated by estrogen receptor (ER) α or β. ERs act primarily as transcriptional factors through two activation functions (AFs), AF1 and AF2, but they can also elicit membrane-initiated steroid signaling (MISS). The aim of the present study was to define ER pathways involved in E2 effects on mandibular bone. Using mice models targeting ERβ or ERα, we first show that E2 effects on mandibular bone are mediated by ERα and do not require ERβ. Second, we show that nuclear ERαAF2 is absolutely required for all the actions of E2 on mandibular bone. Third, inactivation of ERαMISS partially reduced the E2 response on bone thickness and volume, whereas there was no significant impact on bone mineral density. Altogether, these results show that both nuclear and membrane ERα are requested to mediate full estrogen effects in the mandible of growing mice. Finally, selective activation of ERαMISS is able to exert an effect on alveolar bone but not on the cortical compartment, contrary to its protective action on femoral cortical bone. To conclude, these results highlight similarities but also specificities between effects of estrogen in long bones and in the mandible that could be of interest in therapeutic approaches to treat bone mass reduction. © 2018 American Society for Bone and Mineral Research.

Assessment of osteoporotic alterations in type 2 diabetes: a retrospective study

OBJECTIVES

To analyze the influence of Type 2 diabetes on bone mineral density (BMD) and panoramic radiomorphometry in postmenopausal females, comparing with results from non-diabetic postmenopausal females.

METHODS

A total of 228 postmenopausal females (mean age: 59.51 ± 11.08 years) were included in this study. Demographics, T scores and Z scores from peripheral dual X-ray absorptiometry (DXA) and mandibular cortical index (MCI) from panoramic radiographs were assessed. Mean comparison between results for diabetics and non-diabetics was carried out with the Student's t-test. In addition, non-parametric correlations between MCI and DXA results were carried out with Spearman's test, at a level of significance of 5%.

RESULTS

Mean Z score values were significantly higher in diabetics than in non-diabetics (p = 0.001). T and Z score values were also significantly correlated with MCI (r = 0.428, p = 0.001, and r = 0.356, p = 0.022, respectively).

CONCLUSIONS

Within the limitations of this study, the present results suggest that Type 2 diabetes might increase BMD in postmenopausal females.

Efficacy of Panoramic Radiography in the Detection of Osteoporosis in Post-Menopausal Women When Compared to Dual Energy X-Ray Absorptiometry

OBJECTIVE

It is a well-known fact that osteoporosis affects the people with old age and remains unnoticeable until the patient presents with fracture. Various studies in the literature reveal that panoramic radiographs may prove to be beneficial in the detection of Osteoporosis in patients. Henceforth this present study was aimed to validate the use of Klemetti Index (KI) on panoramic radiographs so as to detect osteoporosis in the patients at an early stage.

METHODS

60 postmenopausal women were selected. A panoramic radiograph was taken to grade their mandibular cortex on the basis of Klemetti Index. All the panoramic radiographs were evaluated by 5 different Oral Medicine and Radiology specialists. Later all the patients were subjected to dual energy X-ray absorptimetry (DEXA) scan for bone mineral density evaluation. The results were evaluated statistically.

RESULTS

The average accuracy of the five observers to demonstrate normal bone, osteopenia and osteoporosis when compared to DEXA scan was 58.08%, 63.3% and 64.74% respectively. The observations of the 5 observers on the basis of KI were not statistically different from the BMD evaluation done with the help of DEXA Scan.

CONCLUSION

Panoramic radiographs can be used as a screening tool for the evaluation as well as early detection of osteoporosis with the usage of Klemetti Index.

Evaluation of Correlation between Salivary Calcium, Alkaline Phosphatase and Osteoporosis- A Prospective, Comparative and Observational Study

INTRODUCTION

Fixed and/or removable prosthodontics caters to the restorative needs of the largest count of geriatric patients whose rehabilitative procedures depend on the quality and quantity of available bone. The common diagnostic parameters for quantifying bone may involve an invasive blood examination, an expensive bone densitometry procedure or a urine analysis. Sialometry involving the basic biochemistry of saliva analysis may be proposed as an alternative to the conventional investigative protocol and its usefulness may be attributed owing to its non invasive and simpler procedure.

AIM

The aim of this study was to compare the salivary calcium and alkaline phosphatase among osteoporotic, osteopenic and normal edentulous subjects.

MATERIALS AND METHODS

A prospective, comparative and observational study was carried out on 80 selected edentulous subjects (40 males and 40 females) aged 55-75 years (30 osteoporotic, 30 osteopenic and 20 control). A sample of saliva was taken for the study. Salivary calcium was measured by Arsenazo reaction; and alkaline phosphatase by the International Federation of Clinical Chemistry (IFCC) method. Statistical analysis was done by unpaired t-test. A comparison was made in the levels of salivary calcium and alkaline phosphatase with that of osteoporosis and osteopenia.

RESULTS

The mean salivary calcium and alkaline phosphatase levels were found to be significantly higher in the osteoporotic and osteopenic edentulous subjects as compared to the control group.

CONCLUSION

Salivary calcium and alkaline phosphatase are increased significantly in case of osteoporosis and osteopenia. Hence, screening of salivary samples of patients may be an effective indicator for the detection of underlying disorders of bone metabolism.

Detection of Vascular Disease Risk in Women by Panoramic Radiography

Low bone mineral density and rapid bone loss of the skeleton are associated with mortality risk from vascular diseases in post-menopausal women. Panoramic radiographic measurements are considered as indicators of skeletal bone mineral density or bone turnover. We hypothesize that such measurements may be associated with vascular disease risk in post-menopausal women. Associations of mandibular cortical shape and width on panoramic radiographs with skeletal bone mineral density and risk factors related to vascular diseases were investigated in 87 post-menopausal women. Cortical shape was associated with skeletal bone mineral density, low-density lipoprotein cholesterol, apolipoprotein B, resting heart rate, and endothelial dysfunction. Cortical width was associated with skeletal bone mineral density, low-density lipoprotein cholesterol, and apolipoprotein A1. Dentists may be able to refer women with increased risk of vascular diseases, as well as low bone mineral density, to medical professionals for further examination by panoramic findings.

Association between number of teeth present and mandibular cortical erosion in Japanese men and women aged 40 years and older: A cross-sectional study

Mandibular cortical erosion detected on dental panoramic radiographs is associated with increased risk of osteoporosis in older adults. Additionally, many reports have demonstrated an association between decreased number of teeth present and osteoporosis. However, whether mandibular cortical erosion is associated with a decreased number of teeth remains unclear. The purpose of this study, therefore, was to clarify the association between mandibular cortical erosion and number of teeth present in Japanese men and women aged 40 years and older. Among patients who visited our university hospital and underwent dental panoramic radiography for the diagnosis of dental diseases, 839 patients (293 men and 546 women) aged 40–89 years (mean [SD], 63.7 [10.6] years) participated in this study. Multiple regression analysis revealed that mildly to moderately eroded cortex (p = 0.007) and severe eroded cortex (p < 0.001) were significantly associated with a decreased number of teeth present. Analysis of covariance adjusted for covariates revealed a significant association between mandibular cortical erosion category and number of teeth present (p < 0.001). Subjects with a severely eroded cortex had significantly fewer teeth present than those with a normal cortex (mean [SE], 20.7 [0.5] vs. 23.4 [0.3], p < 0.001) or mildly to moderately eroded cortex (22.2 [0.4], p = 0.04). Subjects with a mildly to moderately eroded cortex had significantly fewer teeth present than those with a normal cortex (p = 0.033). Our results suggest the significant association between mandibular cortical erosion and number of teeth present in Japanese men and women aged 40 years and older.

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.

Relationship between the mandibular cortical index and calcaneal bone mineral density in postmenopausal women

BACKGROUND AND OBJECTIVE

In clinical practice, a comparative analysis of bone mineral density (BMD) is carried out by examining different skeletal bones. This is useful for screening of postmenopausal osteoporosis (OP). The objective of this study was to determine the relation between the mandibular cortical index (MCI) and calcaneal BMD among postmenopausal women.

MATERIALS AND METHODS

The study sample included 129 randomly selected postmenopausal women aged 50-77 years. The participants were examined using panoramic radiography for the analysis of the cortical layer in the mandibular base for MCI determination and using DXL for the examination of calcaneal BMD. According to T scores, the subjects were divided into three groups (Groups 1, 2, and 3). The panoramic radiographic examination of the mandible was performed; the MCI was determined and distributed into groups (C1; C2; C3). The MCI validity in determining the calcaneus BMD status was analyzed.

RESULTS

The differences in BMD were statistically significant between Groups C1 and C3 (P<0.01), Groups C2 and C3 (P=0.01), and between the calcaneal BMD groups (P<0.001). There was a statistically significant inverse correlation between the MCI and calcaneal BMD (r=-0.3; P<0.001). The changes characteristic of Group C2 were documented more frequently than those of other morphological groups. The analysis of the MCI validity in BMD status showed low sensitivity (69.4%) and specificity (53.9%).

CONCLUSIONS

The relation between MCI and calcaneal BMD was determined. The diagnostic discrimination of the MCI was found to be not sufficient in screening the women with postmenopausal osteoporosis and its application in clinical practice might be limited.

Periodontal Health in Women With Early-Stage Postmenopausal Breast Cancer Newly on Aromatase Inhibitors: A Pilot Study

BACKGROUND

Aromatase inhibitor (AI) use results in low estrogen levels, which in turn affect bone mineral density (BMD). Periodontitis, alveolar bone loss, and tooth loss are associated with low BMD. The goal of this study is to assess the prevalence of periodontitis and perceived oral health and evaluate salivary biomarkers in postmenopausal women who are survivors of early-stage (I to IIIA) breast cancer (BCa) and receive adjuvant AI therapy.

METHODS

Participants included 58 postmenopausal women: 29 with BCa on AIs and 29 controls without BCa diagnoses. Baseline periodontal status was assessed with: 1) periodontal probing depth (PD); 2) bleeding on probing (BOP); and 3) attachment loss (AL). Demographic and dental utilization information was gathered by questionnaire. Linear regression modeling was used to analyze the outcomes.

RESULTS

No differences were found in mean PD or number of teeth. The AI group had significantly more sites with BOP (27.8 versus 16.7; P = 0.02), higher worst-site AL (5.2 versus 4.0 mm; P <0.01), and more sites with dental calculus (18.2 versus 6.4; P <0.001) than controls. Linear regression adjusted for income, tobacco use, dental insurance, and previous radiation and chemotherapy exposure demonstrated that AI use increased AL by >2 mm (95% confidence interval, 0.46 to 3.92). Median salivary osteocalcin and tumor necrosis factor-α levels were significantly higher in the AI group than the control group.

CONCLUSION

This first investigation of the periodontal status of women initiating adjuvant AI therapy identifies this population as having an increased risk for periodontitis.

Identifying dental panoramic radiograph features for the screening of low bone mass in postmenopausal women

A retrospective cohort study was performed to evaluate the use of panoramic radiographs as a screening tool for low bone mass in postmenopausal women. Female subjects aged ≥50 years were included. The predictor variables were gonial angle, antegonial angle, mandibular cortical bone integrity, periodontal disease status, and number of remaining teeth. The primary outcome variable was bone mineral density status. Descriptive and logistic regression statistics were computed; P<0.05 was considered significant. The sample was composed of 273 subjects, aged 50-89 years. Visual assessment of mandibular cortical bone integrity demonstrated a statistically significant correlation with low bone mass diagnosis on univariate logistic regression (P=0.019), but lost significance on multivariate analysis with age, body mass index, and number of remaining teeth (P=0.6). A visual estimation of the mandibular cortical bone integrity from panoramic radiographs may be useful for identifying postmenopausal women at high risk for osteoporosis.

Radiomorphometric indices of the mandible - an indicator of osteoporosis

INTRODUCTION

Osteoporosis is a regressive change which occurs in the bone and it is seldom diagnosed before the occurrence of fractures. Hence, determination of mandibular bone density is of paramount importance for the detection of this silent disease.

AIMS AND OBJECTIVES

The purpose of this study was to evaluate the influences of gender and age on the radiomorphometric indices and to assess the differences in the various indices, if any, between digital and analog radiographs.

MATERIALS AND METHODS

Two hundred and fifty six panoramic radiographs (128 digital and 128 analog) were obtained and they were grouped into 8 age groups which were between 21 to 60 years with 5 year intervals between them, with equal sex distributions. The mandibular cortical index (MCI), mental index (MI) and panoramic mandibular index (PMI) were analyzed.

RESULTS

C2 and C3 categories of MCI increased as age advanced in females. MI showed a significant difference in genders and MI Values decreased from younger to older females. PMI (p<0.05) was significant for both the genders.

CONCLUSION

This study showed that MCI, MI and PMI indices were useful for identifying patients with low skeletal bone mineral densities (BMD) or osteoporosis and that digital panoramic radiographs were better than analog radiographs for measuring the indices.

Use of digital panoramic radiography as an auxiliary means of low bone mineral density detection in post-menopausal women

OBJECTIVES

To correlate the radiomorphometric indices obtained using digital panoramic radiography (DPR) with bone mineral densities, evaluated by the dual-energy X-ray absorptiometry test, in a population of post-menopausal females to identify patients with asymptomatic low bone mineral densities.

METHODS

The morphology of the mandibular cortex was evaluated using the mandibular cortical index (MCI) and the inferior mandibular cortex width was evaluated using the mental index (MI) in 64 female patients who had undergone dual-energy X-ray absorptiometry assessment. Of these patients, 21 were diagnosed with osteopaenia and 20 with osteoporosis, and 23 were normal. Three new indices for evaluating the inferior mandibular cortex width were designed: the mental posterior index 1 (MPI1), MPI2 and MPI3. Statistical analyses were performed using the χ(2) and Kruskal-Wallis tests and the receiver operating characteristic curve.

RESULTS

There were significant differences between the normal and lower bone mineral density groups (osteopaenia and osteoporosis) for MCI (p < 0.01). In the osteoporosis group, the MI, MPI1, MPI2 and MPI3 were significantly different from the normal and osteopaenia groups (p < 0.05). The MI, MPI1, MPI2 and MPI3 showed that there is an area in the mandibular cortex, located between the mental foramen and the antegonial region, which is valid for identifying females at high risk for osteoporosis.

CONCLUSIONS

The MCI, MI, MPI1, MPI2, and MPI3 radiomorphometric indices evaluated using DPR can be used to identify post-menopausal females with low bone densities and to provide adequate medical treatment for them.

Diagnostic efficacy of panoramic radiography in detection of osteoporosis in post-menopausal women with low bone mineral density

Objective:

The aim of the study was to evaluate panoramic radiograph, a commonly taken dental radiograph as a screening tool to detect early osseous changes (normal, mildly or severely eroded) of the mandibular inferior cortex and measure the mandibular cortical width (CW) in post-menopausal women and correlate it with the bone mineral density (BMD) measured by the ultrasound bone sonometer at the mid-shaft tibia region.

Materials and Methods:

The study included females between 45 years and 65 years of age in their post-menopausal stage (no menstruation for at least 6-12 months). Mandibular indices (mandibular CW and mandibular cortical shape) were evaluated from panoramic radiographs. The BMD assessment was carried out at the mid-shaft tibia region, exactly half-way between the heel and the knee joint perpendicular to the direction of the bone, using an ultrasound bone sonometer. It is a non-invasive device designed for quantitative measurement of the velocity of ultrasound waves as speed of sound in m/s, capable of measuring bone density at one or more skeletal sites. Using 1994 WHO criteria the study subjects were categorized as Group 1: Normal, Group 2: Osteopenia, Group 3: Osteoporosis. (WHO T score for tibia BMD can be used as a standard).

Results:

The diagnostic efficacy of the panoramic radiograph in detecting osseous changes in post-menopausal women with low BMD was shown to have 96% specificity and 60% sensitivity with mandibular cortical shape and 58% specificity and 73% sensitivity with mandibular CW measurement. Factorial ANOVA analysis carried out indicated a significant correlation of BMD classification with mandibular cortical shape (F = 29.0, P < 0.001, partial eta squared [η²] =0.85), a non-significant correlation with mandibular CW, (F = 1.6, P = 0.23, η² = 0.86), and a more significant correlation with combined cortical shape and width (F = 3.3, P < 0.05, η² = 0.70).

Conclusion:

The study concludes that the combined mandibular cortical findings (P < 0.05) and mandibular cortical shape erosion alone (P < 0.001) on panoramic radiograph are effective indicators of osteoporosis in post-menopausal women.

Salivary calcium concentration as a screening tool for postmenopausal osteoporosis

AIM

Measurements of salivary calcium level may be a useful screening tool for osteoporosis in postmenopausal women. The purpose of this study was to clarify whether this measure is valid compared with dual-energy X-ray (Bone Mineral Density) screening tools in osteoporosis.

METHODS

A case-control study was carried out in 40 postmenopausal women with osteoporosis (T-score ≤ -2.5) and 40 women without osteoporosis (T-score > -1 bone mineral density). Salivary samples were collected and calcium concentrations were measured and expressed as mg/dL. Receiver operating characteristic curve analyses was used to determine the optimal cut-off thresholds for salivary calcium in healthy postmenopausal women.

RESULTS

The cut-off point for salivary calcium was 6.1 mg/dL. The sensitivity and specificity, respectively, for identifying women with osteoporosis, were 67.5 (95%CI 52.33-82.67) and 60% (95%CI 44.62-75.38). The area under curve (AUC) was 0.678 (95%CI 0.56-0.79), the positive predictive value (PPV) was 62.79 (95%CI 47.74-77.84) and negative predictive value (NPV) was 64.86% (95%CI 49.27-80.46). The positive likelihood ratio was 1.688 and the negative likelihood ratio was 0.542.

CONCLUSIONS

Salivary calcium concentration discriminates between women with and without osteoporosis and constitutes a useful tool for screening for osteoporosis.

Association between periodontitis and systemic bone mineral density in Japanese community-dwelling postmenopausal women

OBJECTIVE

The purpose of this cross-sectional study was to evaluate the association between loss of attachment (LA) which is clinical index of periodontitis and bone mineral density (BMD) of the lumbar vertebrae and femur measured with dual energy X-ray absorptiometry (DXA) in Japanese community-dwelling postmenopausal women.

SUBJECTS AND METHODS

Subjects were 374 [corrected] women aged 55-74. The oral cavity was divided into 6 areas according to the WHO's method for the determination of the clinical attachment level score (CALscore); the LA was measured at 6 sites using a WHO probe in 17, 16, 11, 26, 27, 37, 36, 31, 46, and 47, and the values were recorded in mm. Then, we assessed BMD of the lumbar vertebrae (L2-L4) and femur (femoral neck, proximal part) by DXA. Based on these data, analysis of covariance was used to estimate relation between periodontitis and systemic BMD status excluding effect of age. Multiple linear regression analysis was used to estimate relation between periodontitis and BMD adjusted for 17 variables.

RESULTS

Significant differences were observed in the mean value between the mean CALscore=0 and CALscore≥1 groups in the Z value in lumbar vertebrate (106.9±18.7 vs. 102.3±1.0, p<0.05, t-test). Multiple regression analysis was conducted using the mean LA as dependent variable. Lumbar vertebral BMD (regression coefficient: B=-1.039±0.379, p=0.007), femoral neck BMD (B=-1.332±0.627, p=0.034), and proximal femoral BMD (B=-1.329±0.536, p=0.014) all exhibited a significant negative correlation with the mean LA.

CONCLUSION

A significant negative correlation was observed between periodontal disease and truncal bone BMD in this study.

Radiological and histologic studies of the mandibular cortex of ovariectomized monkeys

OBJECTIVE

The objective was to study the radiological and histologic changes in the mandibular cortices of ovariectomized monkeys.

STUDY DESIGN

Twelve female, adult, Cynomolgus monkeys (Macaca fascicularis) were used. Under anesthesia, 1 group was bilaterally ovariectomized (OVX), and the other (control group) underwent sham surgery. Seventy-six weeks after surgery, the monkeys were humanely killed, their mandibles were excised, and their mandibular inferior cortices (MIC) and adjacent cortices were examined histologically and with panoramic radiographs and micro computed tomography.

RESULTS

Striped shadows were seen on the endosteal side of the OVX cortices on panoramic radiographs. Histologic observation revealed many enlarged pores with eroded surfaces and calcein labeling (indicating osteon remodeling) in the OVX cortices.

CONCLUSIONS

In the MIC and adjacent cortices of OVX monkeys, enlarged Haversian canals were seen and there were indications of a high rate of bone turnover. The enlarged Haversian canals resulted in striped shadows and unclear endosteal margins on radiographic images.

Reliability of mandibular cortical index and mandibular bone mineral density in the detection of osteoporotic women

OBJECTIVES

Measuring the bone mineral density (BMD) of the femur and lumbar vertebrae has been the traditional method for determining osteoporosis in women. In this study, we tried to determine the relationships between mandibular dual-energy X-ray absorptiometry (m-DXA) values obtained with a new methodology, mandibular cortical index (MCI), total BMD values of the femur and lumbar vertebrae in 80 women with osteoporosis determined by DXA in conformity with T-score thresholds, as defined by the World Health Organization (WHO).

METHODS

m-DXA and panoramic radiography were performed on 80 women with osteoporosis. m-DXA was calculated by manual analysis of DXA scans. MCI was determined by the appearance of the mandibles on panoramic radiographs. DXA measurements of the skeletal BMD (femur and lumbar vertebras) and MCI values were also calculated. Correlations between these variables were assessed.

RESULTS

Although there were no correlations between skeletal BMD (total BMD values of the femur and lumbar vertebras) and mandibular measurements (mDXA and MCI), we found that there was a significant correlation between the skeletal BMDs (r = 0.355, P = 0.001).

CONCLUSIONS

It is concluded that no significant correlations were found between the mandibular and non-mandibular measures in women with osteoporosis.

Triage screening for osteoporosis in dental clinics using panoramic radiographs

Many patients with osteoporosis go undiagnosed because typically no symptoms are present before a fracture. Triage screening to refer patients to appropriate medical professionals for further investigation would be useful to address the increase in the incidence of osteoporotic fractures. Dental clinics may offer a new triage screening pathway because dentists frequently take radiographs of bones in the course of dental treatment. A major premise for such triage screening in dental clinics is that dentists can readily use a screening tool in their dental practice. For example, cortical width and shape of the mandible detected on panoramic radiographs may be appropriate indices for triaging individuals with osteoporosis. To date, several investigators have demonstrated significant associations between cortical indices on panoramic radiographs and bone mineral density of the skeleton generally, such as the spine and femur, biochemical markers of bone turnover and risk of osteoporotic fractures. Further, in two recent Japanese clinical trials, approximately 95% of women who were identified by trained dentists in their clinics using cortical shape findings did have osteopenia or osteoporosis. These findings support the possibility that dental clinics may offer a new triage platform to identify individuals with otherwise undetected osteoporosis.

Relationships between mandibular cortical bone measures and biochemical markers of bone turnover in elderly Japanese men and women

OBJECTIVE

The aim was to clarify the association between dental panoramic radiography measures of mandibular inferior cortical shape and biochemical markers of bone turnover in elderly men and women.

STUDY DESIGN

Subjects were 80-year-old men (n = 85) and women (n = 153). Mandibular cortical shape and width were evaluated on dental panoramic radiographs. Bone formation and resorption, respectively, were estimated by serum levels of carboxy-terminal propeptide of type I collagen (PICP) and serum type I collagen carboxy-terminal telopeptide (ICTP).

RESULTS

Eroded cortices of the mandible were significantly associated with increased serum PICP levels (P = .005) in women. Lower mandibular cortical width quartiles were also significantly associated with increased serum PICP levels in men (P = .020) and women (P = .006).

CONCLUSIONS

Mandibular inferior cortical measures detected on dental panoramic radiographs may be associated with bone formation rates and be useful in predicting osteoporosis in elderly Japanese men and women.

Zoledronate reverses mandibular bone loss in osteoprotegerin-deficient mice

To characterize the changes in osteoprotegerin-deficient (OPG-/-) mice mandibles and the possible mandibular bone loss prevention by zoledronate. This preventive effect in the mandible differed from that in the proximal tibia and was independent of the OPG pathway.

INTRODUCTION

The study aimed to characterize both the changes in the mandible in osteoprotegerin-deficient (OPG-/-) mice and possible mandibular bone loss prevention by zoledronate.

METHODS

Twenty-eight 6-week-old female mice (C57BL/6J), including OPG-/- (n = 21) and wild-type (WT) (n = 7) mice, were assigned to four groups after 2 weeks of acclimatization to local vivarium conditions: wild mice with vehicle (WT group); OPG-/- mice with vehicle (OPG-/- group); and OPG-/- mice that were subcutaneously injected with either 50 or 150 microg/kg zoledronate (Zol-50 and Zol-150 groups, respectively). Mice were sacrificed at 4 weeks after these treatments and after fasting for 12 h. Sera were harvested for biochemical analyses. The right mandible and tibia of each mouse were selected for microCT analysis. Student's t-test was performed for comparisons of bone parameters at different sites in the WT group. Analysis of variance (ANOVA) was used to compare the biomarkers and bone parameters in the different treatment groups.

RESULTS

Serum bone-specific alkaline phosphatase (B-ALP) and tartrate-resistant acid phosphatase 5b (TRACP-5b) were significantly decreased in WT mice as compared to the levels in the OPG-/- mice (P < 0.05). Zoledronate treatment decreased the high serum B-ALP activity observed in OPG-/- mice to the levels seen in WT mice, while serum TRACP-5b concentrations were decreased to levels even lower than those in WT mice. There were substantial variations in BMD and microstructure of the mandibular and proximal tibial trabeculae. Mandibular bone loss was less affected by OPG gene deprivation than the proximal tibia was. Both zoledronate groups showed greater BMD, trabecular BV/TV, Tb.Th, Tb.N, and Conn.D and a significant decrease in Tb.Sp and SMI as compared to the findings in OPG-/- mice (P < 0.05). However, higher apparent BMD and more compact plate-like trabeculae were observed in the mandible after treatment with zoledronate as compared to the findings in the proximal tibia. No significant differences were found in any parameter in both zoledronate groups.

CONCLUSIONS

The present study showed that zoledronate could reverse the significant bone loss in mice mandibles that was induced by OPG gene deficiency. This preventive effect, which was accompanied with considerable inhibition of bone turnover, differed in the mandible and in the proximal tibia and was independent of the OPG pathway.

Assessment of panoramic radiomorphometric indices in Turkish patients of different age groups, gender and dental status

OBJECTIVES

The aim of the study was to determine the distribution of the appearance of the inferior mandibular cortex (Mandibular Cortical Index (MCI)) in a large Turkish population group and to assess a range of values for cortical width at the mental foramen region (Mental Index (MI)) and the ratio of the thickness of the mandibular cortex to the distance between the inferior margin of the mental foramen and the inferior mandibular cortex (Panoramic Mandibular Index (PMI)) according to the MCI. In addition, we assess how age, sex and dental status affected the MCI.

METHODS

Panoramic radiographs of 1,863 patients, 698 (37.5%) men and 1,165 (62.5%) women over 20 years old, were assessed during 2005-2006 from the files of Baskent University. Gender, age and dental status were recorded for each patient. MCI classifications, MI and PMI values in the MCI groups were evaluated and comparisons were made using logistic regression analysis.

RESULTS

Compared with patients aged 20-49 years, the likelihood of MCI C3 category in patients over 70 years of age and in patients aged 50-69 years of age was 79.14 and 9.17 times higher. The likelihood of the C3 category in edentulous and partially dentate patients was 27.30 and 2.68 times higher than in fully dentate patients, respectively. The likelihood of C3 category in patients with MI <3 mm was 14.86 times higher than in patients with MI >or=3 mm; also, in patients with a PMI of <0.30 this likelihood was 9.78 times higher than in patients with a PMI of >or=0.30.

CONCLUSION

Without respect to gender, edentulous patients with C3 category, MI <3 mm and PMI <0.30 may be seen as high-risk patients for osteoporosis and therefore should be referred for further osteoporosis investigation.

Observer performance in diagnosing osteoporosis by dental panoramic radiographs: results from the osteoporosis screening project in dentistry (OSPD)

Mandibular cortical erosion detected on dental panoramic radiographs (DPRs) may be useful for identifying women with osteoporosis, but little is known about the variation in diagnostic efficacy of observers worldwide. The purpose of this study was to measure the accuracy in identifying women at risk for osteoporosis in a worldwide group of observers using DPRs. We constructed a website that included background information about osteoporosis screening and instructions regarding the interpretation of mandibular cortical erosion. DPRs of 100 Japanese postmenopausal women aged 50 years or older who had completed skeletal bone mineral measurements by dual energy X-ray absorptiometry were digitized at 300 dpi. These were displayed on the website and used for the evaluation of diagnostic efficacy. Sixty observers aged 25 to 66 years recruited from 16 countries participated in this study. These observers classified cortical erosion into one of three groups (none, mild to moderate, and severe) on the website via the Internet, twice with an approximately 2-week interval. The diagnostic efficacy of the Osteoporosis Self-Assessment Tool (OST), a simple clinical decision rule based on age and weight, was also calculated and compared with that of cortical erosion. The overall mean sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the 60 observers in identifying women with osteoporosis by cortical erosion on DPRs were 82.5, 46.2, 46.7, and 84.0%, respectively. Those same values by the OST index were 82.9, 43.1, 43.9, and 82.4%, respectively. The intra-observer agreement in classifying cortical erosion on DPRs was sufficient (weighted kappa values>0.6) in 36 (60%) observers. This was significantly increased in observers who specialized in oral radiology (P<0.05). In the 36 observers with sufficient intra-observer agreement, the overall mean sensitivity, specificity, PPV, and NPV in identifying women with osteoporosis by any cortical erosion were 83.5, 48.7, 48.3, and 85.7%, respectively. The mean PPV and NPV were significantly higher in the 36 observers with sufficient intra-observer agreement than in the 24 observers with insufficient intra-observer agreement. Our results reconfirm the efficacy of cortical erosion findings in identifying postmenopausal women at risk for osteoporosis, among observers with sufficient intra-observer agreement. Information gathered from radiographic examination is at least as useful as that gathered from the OST index.

Relationship between mandibular inferior cortex and general bone metabolism in older adults

The purpose of this study was to investigate whether a link exists between the jawbone and general bone metabolism. The results of our study indicate that a mandibular inferior cortical erosion finding on dental panoramic radiographs is significantly associated with increased biochemical markers of bone turnover.

INTRODUCTION

The purpose of this study was to investigate whether a link exists between the jawbone and general bone metabolism.

METHODS

We measured values of serum bone-specific alkaline phosphatase (S-BAP) and urinary N-telopeptide cross-links of type I collagen (U-NTX). To evaluate the jawbone, we used mandibular inferior cortex (MIC) classification on dental panoramic radiographs. After 134 subjects were divided into three groups (C1: normal cortex, C2: mildly to moderately eroded cortex, C3: severely eroded cortex), we evaluated the relationship between S-BAP or U-NTX and MIC classification by Scheffe's multiple comparison test.

RESULTS

A significant correlation was found between MIC classification and S-BAP (C1 vs. C2: p < 0.01, C1 vs. C3: p < 0.01, C2 vs. C3: NS). A significant correlation was found between MIC classification and U-NTX (C1 vs. C2: p < 0.01, C1 vs. C3: p < 0.001, C2 vs. C3: p < 0.01).

CONCLUSIONS

The results of our study indicate that the mandibular inferior cortical erosion finding on dental panoramic radiographs is significantly associated with increased S-BAP and U-NTX levels. We suggest that there is an association between the jawbone and general bone metabolism.

Relationship between BMD, dental panoramic radiographic findings and biochemical markers of bone turnover in diagnosis of osteoporosis

OBJECTIVE

Mandibular indices, measured on panoramic radiographs, may be useful screening implements for low skeletal bone mass density (BMD). Recent studies suggest that radiographic examination of mandible may constitute an effective process for the early diagnosis of osteoporosis. Biochemical markers of bone turnover may be of value for prediction of individual bone loss and they may help in predicting risk of fracture in elderly women. In contrast to the vast information available on dental radiographic findings and BMD only scarce data exist on the relationship between panoramic mandibular indices and biochemical markers. The aim of this study was to examine the diagnostic performance of dental panoramic radiography and biochemical markers of bone turnover in relation to BMD at the spine in a group of postmenopausal women.

SUBJECTS AND METHODS

An assessment of the number of lost teeth, mandibular cortical width (MCW) at the mental region and morphologic classification of mandibular inferior cortex (MIC grade) was performed on dental panoramic radiographs in a group of 141 postmenopausal women 38-81 years of age. BMD at the lumbar spine was measured by dual energy X-ray absorptiometry. BMD values were categorized as normal (T-score greater than 1.0), and as indicative of osteopenia (T-score -1.0 to -2.5) or osteoporosis (T-score less than -2.5) according to the World Health Organization classification. Serum bone alkaline phosphatase (BAP) was measured with an enzyme immunoassay. Cross-linked N-telopeptides of type I collagen (NTx) corrected for creatinine secretion, was measured with a competitive-inhibition enzyme-linked immunosorbent assay ELISA.

RESULTS

In our study, a decrease in MCW by 1mm increases the likelihood of osteopenia or osteoporosis to 47% (p-value<0.05), having taken into consideration the effect of the years elapsed since menopause. The increase of alkaline phosphatase (ALP) per unit increase the likelihood of osteopenia or osteoporosis to 14% (p-value<0.05), having checked the effect of the years since menopause. A decrease in MCW by 1mm increases the likelihood of moderately or severely eroded cortex to 97% (p-value<0.001). The increase in ALP per 1 unit increases the likelihood of moderate or severe erosion per 10% (p-value<0.05), taking into account the years since menopause.

CONCLUSIONS

Our results suggest that dentists have sufficient clinical and radiographic information that enables them to play a significant role in early diagnosis of osteoporosis in postmenopausal women. Panoramic radiographs and biochemical markers of bone turnover may be of value for prediction of individual bone loss and they may help in predicting risk of fracture in elderly women.

Estrogen deficiency and its effect on the jaw bones

Estrogen deficiency-induced postmenopausal osteoporosis has become a worldwide problem, inducing low bone mass and microarchitectural deterioration of the bone scaffolding in the vertebrae and long bones. With the prevalence of such osteoporosis on the increase, the influence of this estrogen deficiency on the jaw bones has drawn the attention of researchers and clinicians in the field of dentistry. The aim of this article is therefore to review the microstructural changes occurring after ovariectomy in the jaw bones of animal subjects. Induced estrogen deficiency clearly led to structural changes in the jaw bones and alveolar bone of animal subjects (rats and monkeys). Severe bone loss in the rat alveolar bone was principally caused by high bone resorptive activity. This activity accelerated greatly immediately after ovariectomy, and was then followed by more moderate resorptive activity, which continued over an extended period. Additionally, occlusal hypofunction further greatly accelerated the fragility of the alveolar bone structure in ovariectomized rats. Microstructural damage also seen in the alveolar bone of ovariectomized monkeys was found to be directly connected to their systemic osteoporosis. Recent investigations of the relationship in humans between systemic osteoporosis and jaw bone loss have also suggested that a connection may exist between these two. However, more research is required to confirm this connection in humans as well.

Characterization of mandibular bones in senile osteoporotic mice

At present, little is known about the age-related changes in jaw bones. The aim of this study was to characterize the mandibles of 6 month-old senile osteoporotic mice, SAMP6, and compare with those of age-matched controls, SAMR1. In comparison to SAMR1, SAMP6 showed thinner cortical bone, lower bone volume, and poorly organized collagen matrix. The collagen fibril diameter in SAMP6 was significantly smaller than that of SAMR1. In SAMP6 both collagen content and cross-links were lower than those of SAMR1, but the ratio of the major mature cross-link (pyridinoline) to its precursor reducible cross-link (dehydrodihydroxylysinonorleucine/its ketoamine) was higher in comparison to SAMR1. In addition, the extent of lysine hydroxylation of collagen was higher in SAMP6 than that of SAMR1. These results indicate that not only the quantity of collagen but also its quality are altered in SAMP6 and may result in the age-associated osteoporotic defects of mandibles.

Use of Fuzzy Neural Network in Diagnosing Postmenopausal Women with Osteoporosis Based on Dental Panoramic Radiographs

A thin or eroded cortex of the mandible detected on dental panoramic radiographs is independently associated with low skeletal bone mineral density (BMD) or osteoporosis in postmenopausal women. The purposes of this study were to develop new computer-aided diagnosis system that combines these two panoramic measures by using fuzzy neural networks (FNN) for identifying postmenopausal women with osteoporosis. Dental panoramic radiographs of 100 postmenopausal women who visited our clinic and had BMD assessments at the lumbar spine and the femoral neck were used in this study. Mandibular cortical width and shape were measured by computer-aided systems and used as the inputs. This system partitioned the input space into a set of subspaces using a novel fuzzy thresholding and constructed the fuzzy inference system incorporated with multi layer perceptron neural network. Our results show that the combination of cortical width and shape by using FNN can be used for the identification of postmenopausal women with osteoporosis in dental clinic. Dentists may identify postmenopausal women accurately by using the new FNN based system and refer them to medical professional for BMD testing.

Assessment of mandibular buccal and lingual cortical bones in postmenopausal women

OBJECTIVE

Correlations between the widths of mandibular cortical bones and the bone mineral density (BMD) of the spine were analyzed to evaluate the influence of the general bone condition.

STUDY DESIGN

Thirty postmenopausal women were enrolled in this investigation. The widths of cortical bones in sites of the mental foramen and the BMD of the mandibular cancellous bone were measured using multislice computerized tomography (CT) images. The BMD of the lumbar spine was measured using dual-energy x-ray absorptiometry, and the ratio to the young adult mean (YAM) was obtained.

RESULTS

A weak correlation between the widths of cortical bones and the ratio to the YAM was observed. Also, correlations between the widths of cortical bones and the BMD of the mandible were noted.

CONCLUSION

The widths of buccal and lingual cortical bones in the mesial and distal sites of the mental foramen measured on axial CT images do not serve as a reliable examination for the BMD of the lumbar spine.

Risk of vertebral osteoporosis in post-menopausal women with alterations of the mandible

BACKGROUND

Previous studies have suggested that a thin or eroded cortex of the mandible detected on dental panoramic radiographs is associated with low vertebral bone mineral density (BMD) or osteoporosis. However, those studies did not estimate the multivariate-adjusted risk for low vertebral BMD or osteoporosis associated with alterations of the mandible.

METHODS

BMD of the lumbar vertebrae (L2-L4) was compared among quartiles of cortical width and among three cortical shape categories in 450 post-menopausal women (mean age, 57.2 years), adjusted for potential confounders. The odds ratios for low BMD or osteoporosis according to cortical width and shape were also calculated.

RESULTS

Significant associations were found between cortical width and shape, and vertebral BMD. The odds ratios for low vertebral BMD associated with the second, third and lowermost quartiles of cortical width were 1.71 (95% confidence interval (CI), 0.96-3.05), 2.30 (95% CI, 1.29-4.11) and 5.43 (95% CI, 2.16-10.71), respectively, compared with the uppermost quartile. The odds ratios for osteoporosis according to cortical width category were similar to those for low BMD. The odds ratios for low BMD associated with mildly to moderately and severely eroded cortices were 3.85 (95% CI, 2.37-6.25) and 7.84 (95% CI, 2.57-23.90), respectively, compared with normal cortex. The odds ratios for osteoporosis associated with mildly to moderately and severely eroded cortices were 4.73 (95% CI, 2.54-8.80) and 14.73 (95% CI, 6.14-35.47), respectively.

CONCLUSIONS

Post-menopausal women with alterations of the mandible may have an increased risk for low vertebral BMD or osteoporosis.

Identification of post-menopausal women at risk of osteoporosis by trained general dental practitioners using panoramic radiographs

BACKGROUND

An eroded inferior cortex of the mandible on panoramic radiographs may be useful for identifying post-menopausal women with low bone mineral density (BMD), or osteoporosis. The purpose of this study was to assess whether trained general dental practitioners (GDPs) can identify post-menopausal women with undetected low skeletal BMD as well as spinal fractures by panoramic radiographs in their clinics.

METHODS

Out of 455 women aged 50 years and older who visited the dental clinics of 22 trained GDPs and had panoramic radiographic assessment for the examination of dental diseases between June and December 2004, 168 post-menopausal women were diagnosed as having low skeletal BMD based on cortical erosion findings. Of these women, 39 women aged 50-84 years (mean age (SD, standard deviation), 64.8 (7.4) years) with no previous diagnosis of osteoporosis participated in this study. BMD at the lumbar spine and femoral neck was measured using dual energy X-ray absorptiometry (DXA). Spine fractures were assessed on lateral radiographs obtained at the time of the DXA assessment.

RESULTS

Two women (5.1%) had normal BMD (BMD T-score>-1.0), 21 women (53.9%) had osteopenia (BMD T-score of -2.5 to -1.0) and 16 women (41.0%) had osteoporosis (BMD T-score<-2.5). Eight women (20.5%) had fractures at the thoracic spine, lumbar spine, or both.

CONCLUSIONS

Our results suggest that a high percentage of post-menopausal women with undetected low skeletal BMD as well as spinal fractures may be identified based on trained GDPs' analyses of their panoramic radiographs.

Interaction of obesity and skeletal bone mineral density in tooth retention in Japanese postmenopausal women

OBJECTIVE

To investigate whether being overweight is associated with increased or decreased risk of tooth loss in Japanese postmenopausal women.

DESIGN

The number of remaining teeth (total, anterior, and posterior teeth), mandibular bone height, and mandibular cortical mass were evaluated on the dental panoramic radiographs of 450 Japanese postmenopausal women. The bone mineral densities (BMDs) at the lumbar spine and femoral neck were measured by dual-energy x-ray absorptiometry. These measurements were compared among participants in three body mass index (BMI) categories (underweight, normal BMI, and overweight).

RESULTS

Analysis of covariance adjusted for confounding variables revealed that participants who were overweight had a significantly lower number of total (P = 0.019) and anterior (P = 0.012) remaining teeth than did those with normal BMI, although the former had significantly higher skeletal BMD values than the latter. No significant difference was observed in mandibular bone height between the overweight participants and those with normal BMI. There were no significant differences in the number of remaining teeth between the under- and overweight participants. Overweight participants had significantly higher skeletal BMDs (P < 0.001) and tended to have larger mandibular cortical masses than those who were underweight.

CONCLUSIONS

Despite their higher skeletal BMD, postmenopausal women who are overweight may have an increased risk of tooth loss, especially of the anterior teeth, compared with women who have normal BMI. This risk appears to be similar to that for underweight women.

Comparative study of axial and femoral bone mineral density and parameters of mandibular bone quality in patients receiving dental implants

INTRODUCTION

In view of the increase in the life expectancy of humans and in edentulism of the population above 50 years of age, in which the prevalence of osteoporosis is also higher, it is fundamental to better understand the effects of systemic bone mass loss on the healing process of dental implants and to determine the quality of the bone that surrounds them. The objective of the present study was to compare systemic osteoporosis (axial and femoral) and parameters of mandibular bone quality, and to evaluate osseointegration in postmenopausal women receiving dental implants.

METHODS

The sample consisted of 39 women aged 48-70 years, 19 with a densitometric diagnosis of osteoporosis in the lumbar spine and femoral neck and 20 controls with a normal densitometric diagnosis. Bone mineral density was measured in the patients and controls by dual-energy X-ray absorptiometry. Eighty-two osseointegrated dental implants were placed in the mandible, 39 of them in the osteoporosis group and 43 in the control group. Mandibular bone quality was evaluated by classifying mandibular inferior cortical and trabecular bone on panoramic radiographs and by histomorphometric analysis of a mandibular bone biopsy. Osseointegration was analyzed after 9 months.

RESULTS

No significant difference was observed between patients with osteoporosis and controls when comparing individuals with a normal cortex and those with a severely or moderately eroded cortex determined on panoramic radiographs, although patients with MEC/SEC had lower femoral neck BMD than those with NC (0.688 +/- 0.17 vs. 0.814+/- 0.144 g/cm2, P<0.012). Histomorphometric analysis also revealed no difference in the parameters of bone formation or resorption between the two groups. Implant failure was observed in only one case.

CONCLUSION

We conclude that there is an association between low femoral neck BMD and poor mandibular bone quality as assessed by panoramic radiography. The loss of one implant (1.2%) is compatible with the literature and cannot be attributed to systemic osteoporosis.