RAJIVGANDHIUNIVERSITY OF HEALTH SCIENCES, BANGALORE, KARNATAKA

ANNEXURE – II

PROFORMA FOR REGISTRATION OF SUBJECTS FOR DISSERTATION

NAME OF THE CANDIDATE AND ADDRESS
(IN BLOCK LETTERS) / Dr. SUMA. M. S.
POST GRADUATE STUDENT IN
ORAL MEDICINE AND RADIOLOGY
BAPUJIDENTALCOLLEGE AND
HOSPITAL, DAVANAGERE – 577004.
NAME OF THE INSTITUTION / BAPUJIDENTALCOLLEGE AND HOSPITAL, DAVANAGERE – 577004, KARNATAKA
COURSE OF STUDY AND SUBJECT / MASTER OF DENTAL SURGERY IN
ORAL MADICINE AND RADIOLOGY
DATE OF ADMISSION TO COURSE / 24-05-2007
TITLE OF THE TOPIC / MANDIBULAR BONE MINERAL DENSITY AS A PREDICTOR OF SKELETAL OSTEOPOROSIS - AN ORTHOPANTAMOGRAPHIC STUDY
BRIEF RESUME OF THE INTENDED WORK:
6.1 Need for the study:
Osteoporosisis defined as a skeletal disorder characterized by low bone mass and micro – architectural deterioration which compromises bone strength and increases risk of fracture.
Bone mass has been measured by several techniques like Single or Dual Photon Absorptiometry, Quantitative Computed Tomography, Single or Dual X-ray Absorptiometry(DXA), Quantitative Ultrasound, although the only real gold standard measure of bone mineral density would be by bone biopsy.Since the disease is preventable, diagnostic techniques are of major importance. Access to screening for osteopenia or osteoporosis is often limited, and the Dentist is often the most regularly visited doctor in elderly population where as Panoramic Radiographs are the most frequently used imaging modalities for these patients.
Various studies have demonstrated that osteoporotic individuals have altered morphology of the mandible and also there exist a relationship between the mandibular and skeletal bone mineral densities. Panoramic images have been used to predict the patients with low bone mineral density. DEXA including central and peripheral devices which measures bone mineral density offers best means of obtaining information. Peripheral devices work on high frequency sound waves. It is economical and safe. Peripheral devices serve as an excellent aid for osteoporosis screening.
Radiographic assessment of ‘bone quality’ has applications in implantology and in research, assessing the relationship between oral bone loss and osteoporosis which serves as an aid in early prevention and management of osteoporosis.
Hence our study is intended to know the efficacy of Orthopantamographs in predicting osteoporotic risk individuals.
6.2 REVIEW OF LITERATURE :
A study was conducted to know the comparison between the Klemetti Index and Heel DXA BMD measurements in the diagnosis of reduced skeletal bone mineral density in the elderly. In this study 211 participants out of which 102 men and 109 women aged between 60-96 years underwent Panoramic radiographs and Bone Densitometry (DXA) of both heels. As per Klemetti Index, mandibular cortex on a Panoramic Radiograph was classified as 0 (normal), 1 (moderately eroded) or 2 (severely eroded). Bone mineral density of the heel (DXA of heel) is done by bone densitometer. Patients were classified as normal (BMD 0.27 g/cm2 ) and reduced skeletal bone mineral density (BMD 0.27g/cm2). From logistic regression, the odds ratio of having a bone mineral density measurement below –1.5 standard deviation (SD) was 8.04 in the osteopenic (KI category 0 and 1). Receiver operating characteristic curve (ROC curve) analysis was used to measure the validity of the Klemetti Index indicating osteopenia (KI category 2) in predicting reduced bone mineral density. This provides a sensitivity of 50% and specificity of 89%. Positive and Negative predictive values were 21% and 97% respectively. The area under ROC curve was 0.64. The study demonstrated that negative finding (KI category 2) is highly predictive of absence of osteopenia or osteoporosis as defined by the DXA measurements1.
Another study was conducted to evaluate the usefulness of width and morphology of the inferior cortex of mandible on Panoramic Radiographs in the diagnosis of postmenopausal osteoporosis. This study included 124 Japanese women with amenorrhea and age ranging from 33 to 68 years whose BMI was computed. Panoramic radiographs and CT were performed. The width and morphology of the inferior cortex were selected for comparison with the L3 BMD. Cortical width (MCW) was measured in the region of mental foramen. The value of MCW was classified in to grade 1, grade 2 and grade 3. The morphology of the mandibular inferior cortex (MIC) was measured. Kendall’s correlation coefficients were calculated for the relationship between the L3 BMD and each of the MCW grades and MIC classifications. There was significant negative correlation between the width (Kendall’s t=-0.36 p<0.001) and morphology (Kendall’s t=-0.49, P<0.001) of the mandibular inferior cortex and the L3 TBMD. Their results suggested that Panoramic radiography could be reliable in screening for osteoporosis2.
A study was conducted to compare the Radiomorphometric indices of the mandible on Panoramic Radiographs among three groups of normal, osteopenia and osteoporosis and to determine whether Panoramic Indices have validity in predicting osteoporotic risk. 94 post menopausal women aged between 42-72 years were examined using DEXA of lumbar spine and Panoramic Radiography. BMD of lumbar spine was classified into three groups by WHO classification. Panoramic mandibular index (PMI), Mandibular cortical thickness [Mental Index (MI), Antegonial Index (AI), Gonial Index (GI) and the Mandibular Cortical Index (MCI)] were measured bilaterally on Panoramic radiographs and analysed. There were significant differences among normal, ostaopenic and osteoporotic groups in PMI(I), PMI(S), MI, AI, GI and MCI. The sensitivities of the MCI (93%) and the combination index of MCI and MI (90%) in diagnosing osteopenic or osteoporotic cases were high. The results suggested that the width and shape of the mandibular cortical bone on Panoramic Radiography may highly reflect the systemic osteopenic or osteoporotic conditions of the patients3.
Another study was conducted to investigate the relationship between mandibular bone mineral density [BMD] and that of other skeletal sites and to assess the validity of mandibular BMD as a predictor of BMD in other sites. 40 edentulous females participated in the study who underwent DXA of the lumbar spine [L2-L4], DXA of the right femoral neck, single photon absorptiometry [SPA] of the proximal and distal forearm and DXA of the mandible. Significant correlations were observed between BMD in the mandibular body, ramus and symphysis and all other skeletal sites [P<0.002]. The sensitivity and specificity of mandibular BMD in predicting low bone mass for these patients were determined. The diagnostic threshold for low mandibular BMD was set at one Standard Deviation below the mean , the mandibular body BMD measurements gave high sensitivity [0.8] and specificity [0.97], the symphysis BMD low sensitivity [0.4], but high specificity [0.77] while the ramus BMD had a moderate level of sensitivity [0.6] and high specificity [0.91].It was found that mandibular BMD assessed by DXA correlates significantly with BMD measurements of other skeletal sites. The higher correlation coefficients and the greater sensitivity and specificity for the body of the mandible suggest that this site should be used for any potential clinical application of dental radiograph in detection of osteoporosis4.
Another study was conducted to know the influence of gender and age on the values of Linear Radiomorphometric Indices measured on the lower border of mandible. 200 Dental Panoramic Radiographs were taken out of which 73 were male patients of age 21-87 years and 110 were female patients of age 15-80 years. Dental Panoramic radiographs were taken. Three indices; cortical width at the gonion[GI], antegonion[AI] and below the mental foramen [MI] were measured at the lower border of the mandible bilaterally. The results of the study revealed significant differences between GI measured on the left and right side of the mandible [p<0.001].Male patients demonstrated higher values for MI (Mental Index) than female patients. Female patients older than 65 years showed lower AI (Antegonial Index) values than those younger than 65 years. The results suggested that Dental Panoramic Radiographs is useful as a simple method of screening patients for evaluation of mandibular bone quality prior to dental treatment5.
A study was conducted to know the Mandibular morphological changes in low bone mass edentulous females. In this study 52 female edentulous patients underwent Panoramic Radiography and DEXA of Lumbar spine and Femoral neck. Measurements of Gonial Angle, Antegonial Angle, Antegonial Depth, Antegonial Index and Mental Index were performed. Patients were classified into normal, osteopenic or osteoporic. The gonial angle did not show differences
among the three categories of skeletal bone status [P>0.05]. The antegonial angle was significantly smaller in individuals with low bone mass [P<0.05]. The antegonial depth was significantly greater in osteoporotic [P<0.05] and osteopenic individuals [P<0.05].The AI and MI were significantly smaller in individuals with low bone mass [P<0.05]. However, after age adjustment there were no differences among the groups [P>0.05].The results suggested that edentulous females with low bone mass have a deeper antegonial region and thickness of cortical mandibular bone is highly influenced by age6.
6.3 AIMS AND OBJECTIVES
AIM
To measure the bone mineral density in elderly obtained from Dental Panoramic Radiographs by Panoramic Mandibular Index and Mandibular Cortical Index and comparing with Ultrasonometry of Heel, a Peripheral Ultrasound Bone Densitometry.
OBJECTIVES
1)To measure Radiomorphometric Indices of mandible on 100 Panoramic Radiographs taking into account age and gender of participants and comparing this with Ultrasonometry Heel bone mineral density measurements.
2)To establish a precise technique for measuring bone mineral density in elderly using Dental Panoramic Radiographs.
3)To recommend Dental Panoramic Radiographs as a simple screening aid in osteoporotic risk individual in order to prevent and for better management of osteoporosis.
7. / MATERIALS AND METHODS:
7.1 Source of Data:
The patients for this study were selected from the outpatient Department Of Oral Medicine And Radiology, Bapuji Dental College And Hospital, Davangere.
7.2 Method of Collection of the Data:
100 normal individuals with female patients’ age ranging from 45-65 years and male patients age ranging from 50-65 years.
Inclusion Criteria
1)Elderly normal male and female patients without any known systemic disease with above mentioned age group.
2)All female patients in natural menopause
Exclusion Criteria
1)Patients who are suffering from systemic diseases like hyperparathyroidism, hypoparathyroidism, paget’s disease, osteomalacia, renal dystrophy or osteogenesis imperfecta, cancers with bone metastasis or significant renal impairment.
2)Patients who are on corticosteroids or excessive thyroid hormone or on drugs which affect bone metabolism.
3)Patients who are alcoholics and smokers.
4)Patients with previous history of bone fracture.
Methodology
Taking the consent of the patient, relevant history regarding any systemic diseases, drugs, habits, menstrual history and family history and height, weight, gender and age of the patient are recorded before subjecting them to radiograph and bone densitometry.
BMI [body mass index] is calculated from the measured height and weight of the patient by using weight/square of height.
Dental Panoramic Radiographs will be made by GENDEX-orthoralix 9200 with kilovoltage varying between 70kv-80kv, current of 10 mA and exposure time 12 sec with Kodac films as per methodology suggested by White and Pharoah. All films will be processed under standardized manual processing technique.
Good quality Panoramic Radiographs were viewed using a flat view box in a room with subdued light and Linear Radiomorphometric measurerments are made using caliper which are used to asses Mandibular Cortical Index ( MCI) and Panoramic Mandibular Index (PMI) of mandible,
PMI is calculated by using formula given by Benson et al 3.
MCI is calculated by observing the lower border of mandibular cortex distally from the mental foramen and it is classified into different grades of osteoporosis as given by Klemetti3 .
In order to measure the skeletal bone mineral density, Ultrasonometry of Heel is done by Lunar Achilles Express Imaging Bone Ultrasonometer, a peripheral ultrasound bone densitometer, with specifications using Center frequency 0.5 MHz, single element transmission and reception with requirement of 100-240 VAC 5 Amps. Patient’s Heel scan will be accomplished by the following instructions by operator’s manual and results like stiffness index with WHO classification, T score and Z score with % age matched will be displayed on LCH touch screen 11.5*8.5cm with the graphic display by an internal microline thermal printer with graphical output, through 30-60 seconds measurement.
The values obtained will be compared with standard Z-score given by WHO and the patients are classified as normal, osteopenic or osteoporotic.
All the measurements are tabulated and subjected to statistical analysis like ROC analysis, paired T test, Pearson’s correlation coefficients to know the precision values.
7.3 Does the study require any investigation (or) intervention to be conducted
on patient (or) other humans (or) animals?
Yes, Dental Panoramic Radiograph of Mandible and Ultrasonometry of Heels will be taken with patients consent.
7.4 Has ethical clearance been obtained from your institution?
Yes
8. / LIST OF REFERENCES:
  1. Halling A, Person GR, Berglund J, Johansson O, Renvert S.Comparison between Klemetti Index and Heel DXA bone mineral density measurements in the diagnosis of reduced skeletal bone mineral density in elderly.Journal of osteoporosis international. 2005 Aug; 16(4):999-1003.
  2. Taguchi A, Suei Y, Ohtsuka M, Otani K, Tanimoto K,Ohtaki M.Usefulness of panoramic radiography in the diagnosis of post menopausal osteoporosis in women. Width and morphology of inferior cortex of the mandible.Dentomaxillofacial radiology. 1996; 25:263-267.
  3. Kim J, Nah K, Jung Y, Nah K.Comparison of panorama radiomorphometric Indices of the mandible in normal and osteoporotic women.Korean Journal of Oral Maxillofacial Radiology. 2004;34;69-74.
  4. Horner K, Devlin H, Alsop CW,Hodgkinson IM, Adams JE.Mandibular bone mineral density as a predictor of skeletal osteoporosis.British Journal Of Radiology. 1996; 69(827):1019-1025.
  5. Benson BW, Prihoda TJ, Glass BJ, Antonio S. Variations in adult cortical bone mass as measured on the lower border of mandible. Acta Stomatol Croat 2002;36:199.
  6. Farman AG.Mandibular morphological changes in low bone mass edentulous females ; evaluation of panoramic radiographs.Journal of Oral Surg Oral Med Oral Pathol Oral Endo. 2006; 102:663-8