Bone mineral density in periodontally healthy and edentulous postmenopausal women

(Osteoporosis is the most common metabolic disease among postmenopausal women. Reduced masticatory function caused by tooth loss may be a contributing risk factor of osteoporosis. The present study examined the effect of dentate state on skeletal bone mineral density (BMD) in postmenopausal women. Fourteen periodontally healthy dentate subjects (group H; mean age: 64.0 + 5.5 years) and 12 edentulous subjects (group E; mean age: 67.1 + 2.9 years) were randomly selected from the clinics of the departments of Periodontology and Gerodontology, respectively. Informed consent was obtained from all participants. BMD of the lumbar spine (L2-L4) was measured by dual energy x-ray absorptiometry. In addition, occlusal force was measured in 11 group H subjects and 8 group E subjects by using an occlusal diagnostic system. Risk factors associated with osteoporosis including age, calcium intake, physical activity, and cigarette smoking and causes of tooth loss were assessed by interview and questionnaire sent to all participants. The BMD of group H was 1.07 t 0.21 g/cm2 and that of group E was 0.89 + 0.17 g/cm2, which was significantly different(P< 0.05). The occlusal force of group H and E patients was 312.4 + 148 Nand 56.3 + 36 N, respectively, which was significantly different (P< 0.05). Risk factors such as calcium intake, physical activity, and smoking did not differ significantly between the 2 groups. Thus, the periodontally healthy dentate women, who showed about 6 times higher occlusal force than edentulous women, maintained significantly higher BMD of the lumbar spine than edentulous women. Our results suggest that sufficient masticatory function with periodontally healthy dentition may inhibit or delay the progress of osteoporotic change in skeletal bone or that edentulous women may be more susceptible to osteoporosis.     

Bone mineral density in women using depot medroxyprogesterone acetate for contraception

OBJECTIVE: To evaluate the possible effects of depot medroxyprogesterone acetate injectable contraception on bone mineral density in reproductive-age women. METHODS: We conducted a population-based cross-sectional comparison of bone mineral density levels in women using depot medroxyprogesterone acetate contraception and in women of similar age not using this method. The study recruited 457 nonpregnant women aged 18-39 years who were enrollees of a Washington state health maintenance organization. One hundred eighty-three women were receiving injections and 274 were not. Bone mineral density at several anatomic sites (spine, femoral neck, greater trochanter, and whole body) was measured using dual-energy x-ray absorptiometry. Data on other factors potentially related to bone density were collected through questionnaire and examination. RESULTS: Overall, age-adjusted mean bone density levels were lower for users of this method than for nonusers at all anatomic sites: The mean difference was 2.5% for the spine (P = .03) and 2.2% for the femoral neck (P = .12). Exposure to depot medroxyprogesterone acetate continued to be significantly (P < .01) associated with decreased bone density at the femoral neck, spine, and trochanter after multivariate adjustment for other risk factors related to bone density. Age-specific comparisons indicated that the major differences in bone density between users and nonusers occurred in the youngest age group (women 18-21 years); the mean femoral neck bone density was 10.5% lower (P < .01) for the exposed women, and differences were consistent (P < .01) across all anatomic sites. We also noted a significant dose-response relation between longer use of depot medroxyprogesterone acetate and decreased bone density levels in this age group (P < .01 for all sites). CONCLUSION: These results provide evidence that contraception with depot medroxyprogesterone acetate, particularly long-term use, may adversely affect bone mineral density levels in young women aged 18-21 years. The implications for future bone health need further study.     

Bone mineral density in elite junior Olympic weightlifters

The purpose of this study was to examine the relationship of bone mineral density (BMD) to muscular strength in highly trained young male athletes in order to gain insights concerning the influence of heavy resistance training on BMD. Twenty-five elite junior weightlifters (age, 17.4 +/- 1.4 yr) and 11 age-matched controls (16.9 +/- 1.1 yr) volunteered for this investigation. Measurements of BMD (g.cm-2) utilizing dual energy x-ray absorptiometry were obtained for the lumbar spine (L2-4) and the proximal femur (neck; trochanter, Ward's triangle). The BMD values for the junior lifters were found to be significantly greater at all sites for the junior weightlifters compared with their age-matched control group. The BMD values of the spine and femoral neck of the junior weightlifters when compared with adult reference data (i.e., 20-39 yr old men) were found to be significantly greater. Both simple and multiple regression analyses demonstrated significant relationships of BMD with strength accounting for 30-65% of the variance. These data suggest that in elite junior weightlifters, muscle strength, highly specific to the sport of weightlifting, has a major influence on BMD due to the influence of the chronic overloads experienced in training.     

Nutrition and bone mineral density in premenopausal women

Environmental factors have an important role in osteoporosis. Diet and, in particular, nutrients like calcium, vitamin D or phosphorus were extensively studied as determinants of bone mineral density, but the results remain conflicting and there is no clear evidence for an independent effect of such factors in the bone density of premenopausal women. We studied 66 healthy premenopausal women (20-40 years-old) aiming to relate bone mineral density, as measured in three different sites (distal forearm, lumbar spine and femoral neck) using single X ray and dual energy X-ray absorptiometry, with nutritional intake as estimated by a semi-quantitative food frequency questionnaire. Demographic, anthropometric and other life style variables were also assessed. There was a significant correlation between distal forearm and femoral neck (r = 0.57) or lumbar spine (r = 0.45) bone mineral density. No significant effect of age was observed for distal forearm bone mineral density in these women. In a stepwise multiple linear regression model, evaluating the contribution of all the variables studied, only body mass index (p=0.038) and vitamin A ingestion (p = 0.020) had an independent contribution for the variation in distal forearm bone mineral density. Mean bone mineral density, assessed in the femoral neck (p = 0.003) or the lumbar spine (p = 0.056) was different across tertiles of alcohol ingestion, being higher in non-drinkers. However, among regular drinkers there was a significant positive correlation between alcohol ingestion and femoral neck bone mineral density (Spearman's r = 0.53, p = 0.015). This study shows that the effect of nutrition seems dependent on the anatomical site assessed and that there is a weak correlation between nutritional intake and the actual bone mineral density.     

Vitamin-D-receptor-gene polymorphisms and change in lumbar-spine bone mineral density

Common vitamin-D-receptor (VDR) gene allelic variants predict bone mineral density. We analysed VDR alleles and rate of change of lumbar-spine bone mineral density over 18 months in 72 elderly subjects. 9 BB homozygotes lost bone mineral density but 26 homozygotes for the alternative genotype (bb) did not (mean change -2.3 [SE 1.0] vs 0.9 [0.7]% per year, p < 0.05), irrespective of calcium intake. Among 37 heterozygotes (Bb), however, change in bone mineral density correlated with calcium intake (r = 0.35, p < 0.03). This association between a genetic marker and rate of bone loss in the elderly suggests that the effect of calcium intake on maintenance of bone mass could relate to VDR gene polymorphisms.     

Caffeine and other predictors of bone density among pre- and perimenopausal women

Cryopreservation has proved to be a highly successful method for long-term storage of viable embryos. The objective of this study on rat blastocysts was to define conditions for their cryopreservation. Three cryoprotectants, dimethyl sulfoxide, glycerol, and propanediol/sucrose, were compared in two cooling programs (to -30 or -80 degrees C) and two thawing protocols. The cooling was followed by immersion in liquid nitrogen. Programmed thawing was at the rate of 8 degrees C per minute; fast thawing consisted of direct exposure of the frozen embryos to the ambient laboratory temperature. The survival after the freeze/thaw was assessed from the post-thaw embryo morphology and ability to develop into apparently normal offspring in uteri of foster mothers (embryonic survival). The best method for preservation of rat blastocysts proved to be programmed cooling to -80 degrees C followed by fast thawing with glycerol as cryoprotectant (embryonic survival of 28.1%). In all the experimental groups, the proportion of embryos with good to excellent preservation of morphology was high. With dimethyl sulfoxide, after programmed cooling to -80 degrees C, embryonic survival was 9.9% (programmed thawing) and 17.5% (fast thawing). No embryos survived after programmed cooling to -30 degrees C. However, when the cryoprotectant was propanediol/sucrose, no difference was observed between programmed cooling to -80 degrees C with either method of thawing and programmed cooling to -30 degrees C and fast thawing (12.3, 6.2, and 8.0%, respectively).     

Bone mineral density in pediatric patients with idiopathic hypercalciuria

Between October 1993 and April 1995, a total of 77 neonates requiring mechanical ventilation were enrolled in this study and were randomly divided into two groups. Group A consisted of 31 premature infants (mean birthweight 1.36 +/- 0.29 kg) with respiratory distress syndrome (RDS) and seven neonates (mean birthweight 3.2 +/- 0.5 kg) with meconium aspiration syndrome (MAS). Group B consisted of 31 premature infants (mean birthweight 1.31 +/- 0.3 kg) with RDS and eight neonates (mean birthweight 3.3 +/- 0.5 kg) with MAS. Infants in group A received synchronized intermittent mandatory ventilation (SIMV) and infants in group B received conventional intermittent mandatory ventilation (CIMV) therapy. In premature infants with RDS, our data showed: (i) the duration of ventilation was significantly shorter (P < 0.05) in the synchronized group (156 +/- 122 h) compared to the conventional group (242 +/- 175 h); (ii) significantly fewer (P < 0.05) patients required reintubation in the synchronized group than in the conventional group (three vs 11 patients); (iii) incidence of severe intraventricular hemorrhage (grades 3 and 4) was significantly lower (P < 0.05) in the synchronized group compared to the conventional group (one vs seven patients); (iv) incidence of bronchopulmonary dysplasia was significantly lower (P < 0.05) in the synchronized group than in the control group (one vs seven patients). In neonates with MAS, our data showed no significant difference (P < 0.05) on duration of ventilation, incidence of reintubation, incidence of pneumothorax or mortality rate between synchronized and control groups.     

Bone mineral density and bone markers in relation to vitamin D receptor gene polymorphisms in Chinese men and women

Whether vitamin D receptor gene (VDRG) polymorphism can be used as a predictor for bone turnover rate or bone mass remains controversial. Its role within various ethnic populations are also unsettled. We examined VDRG polymorphism using restrictive enzymes Bsm-I, Apa-I, and Taq-I in 155 men aged 22-88 and 113 premenopausal women aged 40-53. The bone mineral density (BMD) of the vertebrae (L2-4), proximal femur, and total body bone mineral content (tb-BMC) (women only), as well as urinary N-terminal crosslinked fragment of type I collagen (NTX), serum osteocalcin, bone isozyme of alkaline phosphatase, and caboxyterminal propeptide of type I procollagen levels were measured. Chinese men and women exhibited a low prevalence for B (absence of Bsm-I restriction site) phenotypes than white and Japanese. Within the tested samples there were 0.4% BB homozygotes, 6.7% Bb heterozygotes, and 93% bb homozygotes. The distributions of Apa-I polymorphism (9.0% AA, 42.5% Aa, and 48.5% aa) also differed from those reported for the white populations. Most of the Chinese men and women were TT homozygous (96.6%). A comparison of actual values and values adjusted for age and weight of tb-BMC and BMD at the lumbar spine, Trochanter, Ward's triangle, and femoral neck showed no significant difference among three subgroups in each of the three sets of polymorphism. Furthermore, the actual values and adjusted values (adjusted for age) of the four bone markers, respectively, showed no significant differences. We conclude that given the very low prevalence of the suspected high risk genotypes (B, A, and t), and the lack of difference among the polymorphic subgroups, VDRG polymorphism may not be an important determinant of the bone turnover rate and bone mass of Chinese men and women.     

Bone mineral density assessment in children with inflammatory bowel disease

BACKGROUND & AIMS: Children with inflammatory bowel disease (IBD) are at risk for osteoporosis because of undernutrition, delayed puberty, and prolonged corticosteroid use. The aim of this study was to compare bone mineral density (BMD) in children with IBD with that in normal children and to assess the effects of nutritional and hormonal factors and corticosteroid dosages on BMD. METHODS: One hundred sixty-two subjects (99 with IBD and 63 healthy sibling controls) were enrolled. Patients underwent anthropometric assessment, pubertal staging, bone age radiography, and BMD assessment by dual energy x-ray absorptiometry of the lumbar spine, femoral neck, and radius. Laboratory evaluations included serum calcium, phosphate, alkaline phosphatase, 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, parathyroid hormone, osteocalcin, urinary N-telopeptides, albumin, insulin-like growth factor I, and testosterone or estradiol. Cumulative corticosteroid doses were calculated. RESULTS: BMD Z scores at the lumbar spine and femoral neck were lower in patients with IBD, and lower in those with Crohn's disease compared with those with ulcerative colitis. Low BMD persisted after correction for bone age in girls with Crohn's disease (lumbar spine, P = 0.004; femoral neck, P = 0.002). Cumulative corticosteroid dose was a significant predictor of reduced BMD. BMD did not correlate with measures of calcium homeostasis, except elevated serum phosphate and urine calcium levels in girls. CONCLUSIONS: Low BMD occurs in children with IBD (more in Crohn's disease than in ulcerative colitis), especially pubertal and postpubertal girls. Cumulative corticosteroid dose is a predictor of low BMD, but other factors in Crohn's disease remain undetermined.     

Bone mineral density in patients on long-term therapy with levothyroxine

The aim of the study was to determine the influence of replacement and suppressive thyroxine therapy on bone mineral density (BMD). 30 postmenopausal women; 19 on replacement therapy (dose 1.22 +/- 0.35 micrograms/kg; duration 11.4 +/- 7.2 years) and 11 on suppressive therapy (dose 1.45 +/- 0.71 micrograms/kg; duration 9.5 +/- 7.2 years). Controls were 60 healthy women matched for age and menopausal status. BMD at the lumbar spine (L2-L4), femoral neck, Ward's triangle and trochanter was measured by dual-energy absorptiometry. Forearm BMD at distal site was measured by single-photon absorptiometry. Mean thyroid hormone values and TSH were within normal limits, although the patients on suppressive therapy had significantly higher T3 (p < 0.05) than the patients on replacement therapy. BMD on each site was significantly lower in the replacement treated group than in controls. BMD in patients on suppressive therapy was lower, but not significantly, compared to controls. Thyroxine therapy could have an adverse effect on BMD. The magnitude of bone loss depends on the serum level of thyroid hormones and on the functional state of thyroid hormone receptor in bone tissue, as well.     

Association between insulin-like growth factor I and bone mineral density in older women and men: the Framingham Heart Study

Few studies of the GH axis and bone have focused specifically on elderly people. The objective of this study was to determine the association between insulin-like growth factor I (IGF-I) and bone mineral density (BMD) in 425 women and 257 men aged 72-94 who participated in the Framingham Osteoporosis Study component of the Framingham Heart Study in 1992-1993. Serum IGF-I level was determined by RIA. BMD at three femoral sites and the lumbar spine was determined by dual x-ray absorptiometry, and at the radius by single-photon absorptiometry. IGF-I level was positively associated with BMD at all five sites (Ward's area, femoral neck, trochanter, radius, and lumbar spine) in women after adjustment for weight loss and other factors (P < or = 0.01) and protein intake in a subset of participants (0.006 < P < 0.07). A threshold effect of higher BMD was evident at each of the 3 femoral sites and the spine (P < 0.03) but not at the radius for women in the highest quintile of IGF-I (> or = 179 g/liter) vs. those in the lowest four quintiles. IGF-I was not significantly associated with BMD in men. These results indicate that higher IGF-I levels are associated with greater BMD in very old women, and suggest that future clinical trials employing GH may have a role in the development of treatments for older women with osteoporosis.     

Nonsteroidal anti-inflammatory drugs and bone mineral density in older women: the Rancho Bernardo study

Nonsteroidal anti-inflammatory drugs (NSAIDs) are known to inhibit synthesis of prostaglandins and may help prevent bone loss, but no study has shown the differential association of type or dose of NSAID compound with bone mineral density (BMD). The purpose of this study was to determine the relation of NSAIDs by type and dose to BMD. Participants were 932 Caucasian, community-dwelling women aged 44-98 years from southern California. Data were collected from 1988 to 1991 through the use of standardized medical questionnaires. Medication use was validated by a nurse. BMD at the ultradistal and midshaft radii were measured using single-photon absorptiometry, and at the hip and lumbar spine using dual-energy X-ray absorptiometry. Women (mean age, 72 years) were classified into 818 nonusers and 114 regular daily users of NSAIDs, of which 84 used propionic acid NSAIDs and the remainder used acetic acid NSAIDs. Occasional NSAID users were excluded. Women who used propionic acid NSAIDs, but not acetic acid NSAIDs, had higher BMD at all five sites and significantly higher BMD at the midshaft radius and lumbar spine. These differences remained after controlling for known covariates of osteoporosis. When women with self-reported osteoarthritis were excluded from the model, significantly higher BMD in propionic acid NSAID users was also observed at the femoral neck and total hip. Those who concurrently used estrogen and propionic acid NSAIDs had the highest BMD at all sites, suggesting an additive effect. We conclude that regular daily use of propionic acid NSAIDs, with or without simultaneous use of estrogen, may be helpful in preventing bone loss in older women. However, further research is needed to confirm these results before any clinical practice guidelines can be recommended due to the increased risk of serious complications associated with NSAID use.     

Bone mineral density and turnover in children with systemic juvenile chronic arthritis

OBJECTIVE: To assess bone mineral status in a group of children with systemic type juvenile chronic arthritis (JCA), which places them at high risk to develop osteoporosis. METHODS: Bone mineral density (BMD) was measured in 17 children aged 6-18 yrs (mean 14.9 +/- 4.5) with systemic JCA and in 18 matched controls by dual energy x-ray absorptiometry. Bone turnover was determined by quantitative bone scintigraphy, using quantitative single photon emission computed tomography based on skeletal uptake of methylene diphosphonates (MDP uptake). Serum concentrations of minerals, osteocalcin, and bone alkaline phosphatase were determined. Nutrient intake was assessed by a 24 hour dietary recall. RESULTS: Patients with systemic JCA who received corticosteroid therapy had significantly reduced BMD in both the lumbar spine (p < 0.05) and the femoral neck (p < 0.05) compared to controls, whereas BMD values of the non-steroid systemic JCA patients were not different from controls. Bone turnover measurement by MDP uptake showed no difference between patients with JCA and controls. Levels of calcium, phosphorus, alkaline phosphatase. and osteocalcin were within normal limits in all patients. CONCLUSION: Patients with systemic JCA receiving longterm steroid treatment may develop a significant decrease in BMD. The normal MDP uptake values together with normal osteocalcin levels that we observed in our patients indicate that their disease is not associated with enhancement of bone turnover rates. These observations might have therapeutic implications for prevention and management of osteoporosis in JCA.     

Associations between body morphology and bone mineral density in premenopausal women

To investigate whether body morphology, obesity and its long time evolution were associated with lumbar and femoral bone mineral density (BMD) in premenopausal women of the same age. DESIGN: Cross-sectional study. SUBJECTS: 72 healthy premenopausal women born in 1950 (42 years) with a regular physical activity. MEASUREMENTS: BMD measured by dual-X-ray absorptiometry (DEXA) at lumbar spine and proximal femur; body weight, body mass index (BMI), BMI at 20 years (BMI-20), increase in BMI since age of 20 (BMI->20), body circumferences (breast, waist, hip) and their ratios (WHR, BHR, WBR), smoking and alcohol intake. RESULTS: Lumbar spine BMD did not correlate with any anthropometric measurement. Femoral BMDs correlated positively with weight, BMI, BMI-20, breast, waist, WHR and BHR. The BMI-20 explained the 5% and the current BMI the 13% of variance of total femur BMD. After adjustment for weight or BMI, breast circumference and BHR remained significantly correlated with all femoral BMDs sites except neck. Weight was the best predictor for neck BMD (R2 = 0.08; p < 0.02), and BHR for Ward's triangle (R2 = 0.12; p < 0.01) and trochanter (R2 = 0.10; p < 0.001). Alcohol intake, cigarette smoking, and age of menarche were not related to BMDs. CONCLUSION: In premenopausal women of the same age, lumbar spine BMD was not associated with any anthropometric measurement. Greater BHR and its long time of evolution may be determinants of greater femoral BMD (trabecular), whereas body weight may be determinant of femoral neck BMD (cortical). Further studies are needed to determine whether large breast to hip ratio may be considered as a protective factor for femoral osteoporosis.     

Regional bone mineral density interrelationships in normal and osteoporotic postmenopausal women

We describe a prospective study in which bone mineral density (BMD) was measured in total body and regions, proximal femur, lumbar spine, and forearm in 84 apparently normal postmenopausal women with normal spinal radiographs and in 47 women with 1-10 wedged or compressed vertebrae. There was a history of peripheral fracture in 35 of the 84 controls and 30 of the 47 osteoporotics (p < 0.02) but there was no association between vertebral fracture and wrist fracture. At all sites and regions, the differences in BMD between the "normal"and "osteoporotic" women was highly significant and all but "ribs" and "arms" remained significant after correction for menopausal age. In the whole set, and in both subgroups, the coefficients of correlation between sites and regions were all highly significant (p < 0.001). Nonetheless, some sites discriminated better between the two groups than others. Standardized odds ratios (OR) for vertebral fracture versus no-fracture were calculated by logistic regression and expressed as the rise in OR for each standard deviation (SD) fall in bone density. This ratio was greatest (3.4) in "pelvis" and weakest (1.7) in "ribs" but all were statistically significant. Geometric mean regression equations were calculated for all the 78 possible pairs of sites and regions in the 84 normal subjects and the deviations of the osteoporotic women from these normal slopes calculated. In most pairs of sites and regions, the vertebral fracture cases were scattered around the normal group's slope but fell lower down on both axes. The bone deficits in the osteoporotics compared with young normal women ranged from -14% in "head" to -40% in Ward's triangle and the T-scores ranged from -1.9 in "ribs" to -3.9 in the forearm. Sensitivity ranged from 17% in "ribs" to 36.2% in Ward's triangle. Specificity varied between 88 and 94% and the percent correctly classified ranged from 62.6% in "ribs" to 72.5% in Ward's triangle. We conclude that primary postmenopausal osteoporosis affects the entire skeleton but that some sites discriminate better between vertebral fracture and nonfracture cases regardless of whether they represent cortical or trabecular bone.     

Muscle mass and fat mass in relation to bone mineral density in very old men and women: the Framingham Heart Study

Aim of the study was investigate the cross-sectional relationship between body composition and bone mineral density (BMD) in very old men and women. The study sample consisted of 504 women and 285 men, aged 72-93 yr, participating in examination 22 (1992-1993) of the Framingham Heart Study. Total body BMD, regional BMD, and soft-tissue body composition was measured by dual-energy X-ray absorptiometry. Both muscle mass and percentage body fat were positively associated with total body BMD in women. After adjustment for age, physical activity, smoking status, estrogen use, and thiazide use, BMD increased with increasing tertile of muscle mass (p = 0.007) and with increasing tertile of percentage body fat (p = 0.0001) in women. In men muscle mass, not percentage body fat, was positively associated with BMD. After adjustment for potential confounders, BMD remained associated with muscle mass only (p = 0.02). These results were similar for leg BMD and arm BMD. The study suggests that the influence of muscle and fat mass on bone mineral density is different between very old men and women.     

Nutritional influences on bone mineral density: a cross-sectional study in premenopausal women

The association between current and past dietary intake and bone mineral density (BMD) was investigated in 994 healthy premenopausal women aged 45-49 y. BMD was measured with dual-energy X-ray absorptiometry (DXA). Dietary intake was assessed with a food-frequency questionnaire (FFQ). Energy-adjusted nutrient intakes were grouped into quartiles and mean BMD at the lumbar spine (LS), femoral neck (FN), femoral trochanter (FT), and femoral Wards (FW) were calculated. With higher intakes of zinc, magnesium, potassium, and fiber, LS BMD was significantly higher (P < 0.05-0.006), and a significant difference in LS BMD was also found between the lowest and highest quartiles for these nutrients and vitamin C intake (P < 0.05-0.01). These results remained significant after adjustment for important confounding factors. LS BMD and FT BMD were lower in women reporting a low intake of milk and fruit in early adulthood than in women with a medium or high intake (P < 0.01). High, long-term intake of these nutrients may be important to bone health, possibly because of their beneficial effect on acid-base balance.     

Bone mineral density of the internal auditory meatus by quantitative computed tomography

The bone mineral density of the internal auditory meatus was investigated by means of quantitative computed tomography in 20 normal subjects (40 ears). Investigated portions of the internal auditory meatus were the porus anterior and posterior and the fundus anterior and posterior. Two other portions of the ear, the bony vestibule and lateral wall of the mastoid, were also investigated. The bone density values (calcium carbonate equivalent value) for each portion were analyzed statistically. The following results were obtained: 1) There was no significant difference between the right and left values in any portion. 2) The highest mean value was found in the fundus posterior, the lowest in the porus anterior. There was a significant difference between the values of the fundus and porus. Bone hardness generally correlates with bone density. Thus, the bone hardness of the porus of the internal auditory meatus was appraised to be lower than that of the fundus. These results suggest that this is one of the factors promoting enlargement of the internal auditory meatus in acoustic neuroma.