Cone-beam computed tomography-based investigation of pre-eruptive intracoronal resorption prevalence.

This retrospective study aimed to investigate the prevalence of pre-eruptive intracoronal resorption (PEIR) using cone-beam computed tomography (CBCT) and to explore the mechanism and characteristics of PEIR development. CBCT images of patients aged ≤ 20 years with unerupted teeth at Hiroshima University Hospital were collected. We examined 1530 patients with 10,576 unerupted teeth. Teeth with PEIR were identified for the detailed location and size of the PEIR in the crown using multiplanar reconstruction. The subject and tooth prevalence rates of PEIR were 1.96% and 0.31%, respectively. The teeth that were the most commonly affected by PEIR were mandibular third molars (3.09%). The prevalence of PEIR was significantly higher in females than in males, and higher in the mandible than in the maxilla. No significant difference between in the position of PEIR within the crown was observed. Moreover, CBCT imaging revealed the onset of PEIR in one case. This study demonstrated the prevalence of PEIR and identified statistically significant sex- and location-based differences. Furthermore, one case of CBCT imaging supports the hypothesis that the onset of PEIR was due to resorption after completion of the crown.

Do various imaging modalities provide potential early detection and diagnosis of medication-related osteonecrosis of the jaw? A review.

OBJECTIVE: Patients with medication-related osteonecrosis of the jaw (MRONJ) often visit their dentists at advanced stages and subsequently require treatments that greatly affect quality of life. Currently, no clear diagnostic criteria exist to assess MRONJ, and the definitive diagnosis solely relies on clinical bone exposure. This ambiguity leads to a diagnostic delay, complications, and unnecessary burden. This article aims to identify imaging modalities' usage and findings of MRONJ to provide possible approaches for early detection. METHODS: Literature searches were conducted using PubMed, Web of Science, Scopus, and Cochrane Library to review all diagnostic imaging modalities for MRONJ. RESULTS: Panoramic radiography offers a fundamental understanding of the lesions. Imaging findings were comparable between non-exposed and exposed MRONJ, showing osteolysis, osteosclerosis, and thickened lamina dura. Mandibular cortex index Class II could be a potential early MRONJ indicator. While three-dimensional modalities, CT and CBCT, were able to show more features unique to MRONJ such as a solid type periosteal reaction, buccal predominance of cortical perforation, and bone-within-bone appearance. MRI signal intensities of vital bones are hypointense on T1WI and hyperintense on T2WI and STIR when necrotic bone shows hypointensity on all T1WI, T2WI, and STIR. Functional imaging is the most sensitive method but is usually performed in metastasis detection rather than being a diagnostic tool for early MRONJ. CONCLUSION: Currently, MRONJ-specific imaging features cannot be firmly established. However, the current data are valuable as it may lead to a more efficient diagnostic procedure along with a more suitable selection of imaging modalities.

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.

[Screening for osteoporosis by dental panoramic radiographs].

Cortical measurements (width and shape) of the mandible detected on panoramic radiographs are associated with bone mineral density of the spine and the femur, risk of osteoporotic fractures and bone turnover. Diagnostic efficacy of cortical measurements for identifying postmenopausal women with osteoporosis is almost similar to that of questionnaire-based screening tool. Dental clinic may be one of valuable strongholds in screening for osteoporosis.

Relationship between self-reported periodontal status and skeletal bone mineral density in Japanese postmenopausal women.

OBJECTIVE: Several investigators have linked periodontal disease progression and low skeletal bone mineral density in postmenopausal women. However, little is known about whether self-reported periodontal status is the reflection of skeletal bone mineral density. We investigated whether self-reported poor periodontal status is associated with low skeletal bone mineral density in postmenopausal women. DESIGN: Relationships among self-reported periodontal status, number of teeth remaining, and bone mineral density of the lumbar spine and the femoral neck were evaluated in 253 Japanese postmenopausal women (mean +/- SD, 56.6 +/- 7.7) recruited from the patients who visited our clinic for bone mineral assessment between 1997 and 2003. Self-reported periodontal symptoms included gingival swelling, gingival bleeding, purulent discharge, and tooth mobility at the time of bone mineral assessment. RESULTS: Analysis of covariance adjusted for age, height, weight, years since menopause, duration of estrogen use, and regular oral care revealed that subjects without periodontal symptoms had significantly higher BMD of the lumbar spine than did those with periodontal symptoms (mean +/- SEM, 0.962 +/- 0.014 vs 0.921 +/- 0.013; P = 0.038); however, there were no significant differences in the number of remaining teeth and bone mineral density of the femoral neck between them. The odds of low spine bone mineral density in subjects with periodontal symptoms was 2.01 (95% CI = 1.15 to 3.50). CONCLUSION: Our results suggest that self-reported poor periodontal status may be associated with low bone mineral density of the lumbar spine in postmenopausal women.

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

UNLABELLED: We investigated whether mandibular cortical measures on dental panoramic radiographs are associated with biochemical markers of bone turnover in 82 postmenopausal women. Mandibular cortical shape was significantly associated with biochemical markers and spinal BMD. Our results suggest that dentists may be able to identify postmenopausal women with low BMD by using dental panoramic radiographs. INTRODUCTION: Recent studies suggest that mandibular inferior cortical shape and width on dental panoramic radiographs may be useful screening tools for low skeletal bone mineral density (BMD) or increased risk of osteoporotic fracture. However, little is known as to whether these measures are associated with bone turnover. We investigated relationships among dental panoramic radiographic findings, spine BMD, and biochemical markers of bone turnover in postmenopausal women. MATERIALS AND METHODS: Of 609 women who visited our clinic for BMD assessment between 1996 and 2002, 82 Japanese postmenopausal women, 46-68 years of age (54.1 +/- 4.9 years), were recruited for this study. Mandibular inferior cortical shape (normal, mild/moderate erosion, severe erosion) and width were evaluated on dental panoramic radiographs. BMD at the lumbar spine (L2-L4) was measured by DXA and categorized as normal (T-score > -1.0), osteopenia (T-score, -1.0 to -2.5), or osteoporosis (T-score < -2.5). Bone turnover was estimated by serum total alkaline phosphatase (ALP) and urinary N-telopeptide cross-links of type I collagen (NTx), corrected for creatinine. RESULTS: The odds of low spine BMD in subjects with any cortical erosion were 3.8 (95% CI, 1.2-12.5). Mandibular cortical erosion was significantly associated with increased NTx (p < 0.001) and ALP (p < 0.05) levels. The associations of spine BMD with NTx and ALP were similar. Mandibular cortical width was significantly associated with spine BMD but not with NTx and ALP levels. CONCLUSIONS: Our results suggest that mandibular inferior cortical shape on dental panoramic radiographs may be an indicator of bone turnover and spine BMD in postmenopausal women. Dentists may be able to identify postmenopausal women with increased risk of osteopenia and osteoporosis on routine dental panoramic radiographs.

Association of estrogen and vitamin D receptor gene polymorphisms with tooth loss and oral bone loss in Japanese postmenopausal women.

OBJECTIVE: To investigate the relationship between estrogen receptor (ER) and vitamin D receptor (VDR) gene polymorphisms and tooth loss, oral bone loss, and postcranial bone mineral density (BMD) in Japanese postmenopausal women. DESIGN: Polymorphisms at the ER PvuII and XbaI and VDR BsmI gene sites, number of teeth remaining, oral bone mass, and BMD of the lumbar spine and the hip were evaluated in 149 Japanese postmenopausal women. RESULTS: The distribution of ER PvuII and XbaI and VDR BsmI restriction fragment length polymorphisms was as follows: pp, 30.2%; Pp, 49.7%; PP, 20.1%; xx, 71.8%; Xx, 22.5%; XX, 2.7%; bb, 76.5%; Bb, 22.2%; and BB, 1.3%. Analysis of covariance adjusted for confounding variables revealed that participants with pp allele had fewer teeth remaining than did those with P allele. There were no significant differences in oral bone mass and postcranial BMD among three alleles at the PvuII site. Participants with X and bb allele had less oral bone mass and lower postcranial BMD than did those with xx and B allele, respectively. We could not clarify the positive associations between XbaI and BsmI polymorphism and number of teeth. CONCLUSIONS: PvuII polymorphism was associated with tooth loss, but not with oral bone mass and postcranial BMD. XbaI and BsmI polymorphisms may be associated with bone mass or density; however, PvuII polymorphism might contribute to another unknown pathway related to tooth loss.

Effect of estrogen use on tooth retention, oral bone height, and oral bone porosity in Japanese postmenopausal women.

OBJECTIVE: Recent studies in the United States support the protective effect of estrogen use on tooth retention; however, little is known as to how estrogen promotes tooth retention. The aims of this study were to investigate the effects of estrogen use on tooth retention, oral bone height, and oral bone porosity in Japanese postmenopausal women and to clarify how estrogen promotes tooth retention. DESIGN: Relationships among the number of teeth remaining (total, anterior, and posterior teeth), oral bone height, oral bone porosity, bone mineral density of the lumbar spine and the femoral neck, estrogen use status, and the duration of estrogen use were evaluated in 330 Japanese postmenopausal women (mean age +/- SD, 56.8 +/- 7.6 y). RESULTS: Analysis of covariance adjusted for confounding variables revealed that estrogen users (66 women) tended to have more posterior teeth than did nonusers (264 women) (P = 0.065), although there were no significant differences in number of total (P = 0.196) and anterior (P = 0.751) teeth remaining, oral bone height (P = 0.970), oral bone porosity (P = 0.745), and bone mineral density of the lumbar spine (P = 0.459) and the femoral neck (P = 0.749) between estrogen users and nonusers. Multiple regression analysis showed that the duration of estrogen use was significantly associated with number of total (P = 0.019) and posterior (P = 0.007) teeth remaining, independent of age and oral bone height. CONCLUSION: Our results suggest that estrogen may promote tooth retention by strengthening the periodontal attachment surrounding the teeth, but not increasing oral bone height and not decreasing oral bone porosity.

[Experience of using a filmless system in dental practice at Hiroshima University Hospital, a former university dental hospital].

Our university hospital has had a policy of electronic patient recordkeeping, replacing paper-based recordkeeping, since September 1, 2008. Because the Department of Oral and Maxillofacial Radiology had already been using computed radiography for X-ray systems except for intraoral radiography and storing data in Digital Imaging and Communications in Medicine (DICOM) format, the following three conditions form the basis of the changes we made in relation to the introduction of this policy. We started 1. using imaging plates for intraoral radiography as well and storing the data in DICOM format; 2. diagnosed without the need for film; and 3. referred to past images displayed on the screen of our Radiology Information System (RIS). The introduction of digital intraoral radiography has many advantages: not only does it not require film and can all past images be referred to on the screen of the RIS, but radiation exposure times are also shorter, images can be saved electronically, and thus, film processing is redundant. The system improves efficiency and is also advantageous to patients and staff in other departments.

Use of dental panoramic radiographs in identifying younger postmenopausal women with osteoporosis.

INTRODUCTION: Eroded or thin inferior cortex of the mandible detected on dental panoramic radiographs may be useful for identifying postmenopausal women with low bone mineral density (BMD) or osteoporosis. The purpose of this study was to evaluate whether these panoramic measurements are useful for identifying low BMD or osteoporosis in postmenopausal women younger than 65 years. METHODS: We compared the diagnostic performances of panoramic measurements with those of the osteoporosis self-assessment tool (OST) for identifying women with low BMD (T-score of -2.0 or less at either the lumbar spine or the femoral neck) and osteoporosis (T score of -2.5 or less) in 158 healthy Japanese postmenopausal women aged 46 years to 64 years. Mandibular cortical shape (erosion) and width were evaluated on dental panoramic radiographs. Receiver operating characteristic curve analysis was used to determine the optimal cutoff thresholds for cortical width and OST index. RESULTS: The sensitivity and specificity, respectively, for identifying women with low BMD were 82.3% and 55.2% for OST index, 79.0% and 50.0% for cortical width, and 72.6% and 74.0% for cortical shape. The sensitivity and specificity, respectively, for identifying women with osteoporosis were 86.7% and 46.9% for OST index, 90.0% and 45.3% for cortical width, and 86.7% and 65.6% for cortical shape. Likelihood ratio for identifying women with low BMD was 13.90 for thin cortical width (<3.0 mm) and 10.84 for severely eroded cortex. That for identifying women with osteoporosis was 6.40 for thin cortical width and 7.11 for severely eroded cortex. CONCLUSIONS: Dentists may be able to refer postmenopausal women younger than 65 years for bone densitometry on the basis of incidental findings on dental panoramic radiographs.

Visual assessment of the mandibular cortex on panoramic radiographs to identify postmenopausal women with low bone mineral densities.

OBJECTIVE: The purpose of this study was to determine whether simple visual estimation of the mandibular inferior cortex width on panoramic radiographs is useful for identifying postmenopausal women with low skeletal bone mineral density (BMD). STUDY DESIGN: Panoramic radiographs were made on 100 women aged 50-84 years who also had BMD assessment of the lumbar spine and femoral neck by dual-energy x-ray absorptiometry. The panoramic images were examined twice by 4 observers to evaluate the thickness of the mandibular inferior cortex. RESULTS: Intraobserver agreement varied from moderate to almost perfect. Interobserver agreements varied from fair to almost perfect. Overall mean sensitivity, specificity and positive predictive value in identifying women with low BMD were 54.7%, 82.0%, and 72.5% in the lumbar spine and 51.8%, 82.2%, and 75.7% in the femoral neck, respectively. CONCLUSIONS: Our results suggest that simple visual estimation of the mandibular inferior cortex on panoramic radiographs may be useful for identifying postmenopausal women with low BMD.

Validation of dental panoramic radiography measures for identifying postmenopausal women with spinal osteoporosis.

OBJECTIVE: Measurements of mandibular inferior cortical shape and width detected on dental panoramic radiographs may be a useful screening tool for spinal osteoporosis in postmenopausal women. The purposes of this study were to clarify whether these measures are validated compared with simple screening tools based on questionnaires, such as the osteoporosis self-assessment tool (OST) and whether these measures can be used in postmenopausal women with histories of hysterectomy, oophorectomy, or estrogen use. SUBJECTS AND METHODS: We calculated the diagnostic performances of panoramic measurements and the OST for identifying women with spinal osteoporosis in both 159 healthy postmenopausal and 157 postmenopausal women with histories of hysterectomy, oophorectomy, or estrogen use. Spinal osteoporosis was defined as a bone mineral density T score of -2.5 or less at the lumbar spine. Cortical shape and width were evaluated on dental panoramic radiographs. Receiver operating characteristic curve analyses were used to determine the optimal cutoff thresholds for cortical width and the OST in healthy postmenopausal women. RESULTS: The sensitivity and specificity, respectively, for identifying women with spinal osteoporosis were 89.5% and 33.9% for cortical width, 86.8% and 57.8% for the OST, and 86.8% and 63.6% for cortical shape in healthy postmenopausal women. Sensitivity and specificity, respectively, were 92.5% and 35.0% for cortical width, 72.5% and 58.1% for the OST, and 80.0% and 64.1% for cortical shape in postmenopausal women with histories of hysterectomy, oophorectomy, or estrogen use. CONCLUSION: Dentists may be able to refer postmenopausal women with suspected spinal osteoporosis for bone densitometry on the basis of dental panoramic radiographs with diagnostic performance similar to that of osteoporosis screening tools based on questionnaires.

Dental panoramic radiograph as a tool to detect postmenopausal women with low bone mineral density: untrained general dental practitioners' diagnostic performance.

The detection of postmenopausal women with low bone mineral density (BMD) is an important strategy to reduce the incidence of osteoporotic fracture. Recent studies suggested that incidental findings on dental panoramic radiographs may be used as a tool to detect women with low BMD. However, little is known whether this finding is sufficiently assessed by untrained general dental practitioners (GDPs). The purpose of this study was to investigate: (1) the observer agreement and (2) the diagnostic efficacy in detecting women with low BMD, when untrained GDPs assess the appearance (normal or eroded) of the mandibular inferior cortex on dental panoramic radiographs of postmenopausal women. Twenty-seven GDPs were asked to classify the appearance of the mandibular inferior cortex on dental panoramic radiographs of 100 postmenopausal women who had completed BMD assessments of the lumbar spine and of the femoral neck. Intra-and inter-observer agreements were analyzed with kappa statistics. The diagnostic efficacy (sensitivity, specificity and predictive values) was analyzed by comparing two groups classified by the mandibular inferior cortex (women with normal and women with eroded mandibular inferior cortex) with those classified by BMD (women with normal BMD and women with osteopenia or osteoporosis). The mean sensitivity and specificity were 77% and 40%, respectively, when BMD of the lumbar spine was used as standard and 75% and 39%, respectively, when BMD of the femoral neck comprised the standard. Nineteen untrained GDPs (70%) presented a moderate to almost perfect intra-observer agreement. We conclude that dental panoramic radiograph may be used in clinical dental practice to identify postmenopausal women who have undetected low BMD and should undergo further testing with bone densitometry.

Tooth loss is associated with an increased risk of hypertension in postmenopausal women.

Tooth loss has been associated with an increased risk of vascular diseases such as coronary heart disease and cerebrovascular disease. Little is known whether hypertension is an important factor linking 2 phenomena in postmenopausal women. We compared an incidence of hypertension and traditional risk factors for vascular diseases between 2 age-matched groups: 67 postmenopausal women with missing teeth and 31 without missing teeth. In addition to blood pressure, serum concentration of total cholesterol, high- and low-density lipoprotein cholesterol and triglycerides, plasma angiotensin-converting enzyme activity, plasma angiotensin II concentration, plasma renin activity, and resting heart rate were measured as traditional risk factors for vascular diseases. Subjects without missing teeth had significantly lower diastolic blood pressure than did subjects with missing teeth (P=0.021). The former tended to have lower systolic blood pressure than did the latter (P=0.058). There were no significant differences in other variables between subjects with and without missing teeth. The odds ratio of having hypertension in subjects with missing teeth was 3.59 (95% confidence interval, 1.10 to 11.7) after adjustment of obesity, hypercholesterolemia, and hypertriglyceridemia. Our results suggest that hypertension may be an important factor linking tooth loss and an increased risk of vascular diseases in postmenopausal women.