Relationship between body mass index and local quality of mandibular bone structure in elderly individuals.
BACKGROUND
Human bones decrease in density and increase in porosity beginning at about the third decade of life. The objective of this study was to determine whether mandibular bone mineral density (BMD) and some linear radiomorphometric measurements on dental panoramic radiograph (DPR) are correlated with different categories of body mass index (BMI) in elderly individuals.


METHODS
Cortical width at gonion (GI), at antegonion (AI), and below mental foramen (MI) and the appearance of the cortex of the lower border of the mandible distal to the mental foramina due to resorptive changes (mandibular cortical index [MCI]) were measured bilaterally on the mandible on 136 DPRs of elderly individuals. Using DPRs and copper stepwedge, mandibular BMD was investigated densitometrically. All BMD values were expressed in equivalents of the actual stepwedge thickness. The patients with BMIs from 20 to 25 kg/m(2) were classified as category 1 (the generally accepted range of normal BMI), and the patients with BMIs higher than 25 were classified as category 2 (heavy individuals with a heavy skeleton and a large amount of fat in the body).


RESULTS
The results revealed statistically significant differences in all measured indices between different BMI categories (p <.05 for MI; p <.001 for GI and AI). Statistically significant differences were also found in BMD values between different BMI categories (p <.05); the differences were more pronounced in women. The patients with MCI category 3 had significantly lower BMD values in comparison to MCI category 2 (p <.01). Intraobserver agreement in GI, AI, MI measurement, and MCI assessments was excellent.


CONCLUSIONS
Heavy people have higher BMD and higher values in linear radiomorphometric measurements than lighter people.
Departments of Prosthodontics, School of Dental Medicine, University of Zagreb, Croatia. dkz@email.hinet.hr
D Knezović
DK
Zlatarić
A
A
Celebić
P
P
Kobler
D000368:Aged; D000369:Aged, 80 and over; D015992:Body Mass Index; D015519:Bone Density; D005260:Female; D006801:Humans; D008297:Male; D008334:Mandible / Q000000981:diagnostic imaging*; D008875:Middle Aged; D015588:Observer Variation; D011862:Radiography, Panoramic