Copper deficit as a potential pathogenic factor of reduced bone mineral density and severe tooth wear.

UNLABELLED: The study evaluated if men and women with severe tooth wear were at increased risk of general bone loss. Enamel biopsies obtained from 50 subjects aged 47.5 ± 5 years showed decreased copper content, which was associated with reduced spine bone mineral density, suggesting deficits of this trace element contributing to bone demineralization, enamel attrition, and deteriorated quality of mineralized tissues. INTRODUCTION: The objective of this cross-sectional study was to assess associations between enamel trace minerals and bone mineral density (BMD) in severe tooth wear. We hypothesized that similar factors contributed to both the excessive abrasion of dental enamel and reduced BMD in subjects with tooth wear. METHODS: Fifty patients aged 47.5 ± 5 years with severe tooth wear and 20 age-, sex-, and body mass index (BMI)-matched healthy volunteers with normal dental status were studied regarding dietary intakes of trace elements, serum and salivary copper (Cu), zinc (Zn), and calcium (Ca) concentrations, and serum PTH, osteocalcin, and hydroxyvitamin D levels. Tooth wear was determined using clinical examination based on standard protocol according to Smith and Knight. In all subjects, acid biopsies of the maxillary central incisors were carried out to assess mineral composition of the enamel. Atomic absorption spectroscopy with an air/acetylene flame was used to measure Ca and Zn, and graphite furnace atomic absorption spectroscopy was used to analyze Cu content. BMD was examined using dual energy X-ray absorptiometry. RESULTS: Tooth wear patients had reduced lumbar spine, but not femoral, BMD relative to controls (p < 0.001). No differences were found in enamel Ca concentration and Zn content was slightly higher in tooth wear patients than in controls whereas Cu content was significantly decreased in the patients: 19.59 ± 16.4 vs 36.86 ± 26.1 µg/l (p = 0.01) despite similar levels of Cu in serum and saliva. The differences were independent of serum 25-OH-D, osteocalcin concentrations or PTH either. CONCLUSION: Severe tooth wear is associated with reduced spinal BMD. Enamel in adult individuals with severe tooth wear is low in copper content. Therefore, further work is needed to determine whether copper plays a role in bone pathophysiology in these patients.

Reduced systemic bone mineral density associated with a rare case of tooth and nail syndrome.

PURPOSE: This is the first report of a rare genetic tooth and nail syndrome (TNS) diagnosed in a 14-year-old Caucasian girl with a complete absence of the permanent dentition and, additionally, reduced total and lumbar spine bone mineral density (BMD). This coincidence suggests a new clinical manifestation of the disorder in which genetic factors and/or shared mechanisms may be responsible for the deterioration of the stomatognathic system, anodontia, nail phenotype and osteopenia. Low bone mass appears to be a new component of the syndrome. There is a rationale for bone densitometry scans assuming that patients with TNS may have an increased risk of osteopenia. Reduced BMD and, possibly, impaired bone quality and strength may produce difficulties or even exclude such patients from future treatment with dental implants.

The influence of the occlusal vertical dimension on masticatory muscle activities and hyoid bone position in complete denture wearers.

PURPOSE: Long lasting usage of complete dentures causes lower occlusal vertical dimension, producing potential detrimental consequences. The aim of this study was to investigate how changes in vertical dimension during denture exchange affect muscular activity and hyoid bone position. MATERIAL AND METHODS: Twenty-five edentulous, otherwise healthy patients (14 females, 11 males) aged 70.5 +/- 9 years, wearing their dentures over 5 years but no longer than 15 years (mean 9.8 +/- 5.2), were studied. New dentures were fabricated and the occlusal vertical dimension was recorded on cephalometric radiographs. Cephalograms were analyzed according to Ricketts. The relation of the hyoid bone position to the mandible was estimated. An evaluation of muscular activity was performed using the Biopak Electromyography Recording System synchronized with the T-Scan II Occlusal Analysis System. RESULTS: The occlusal vertical dimension was higher with the new dentures compared with the old dentures. The transition to new dentures was accompanied by a change of the vertical position of the hyoid bone. Digastric muscle activity was lower with the new dentures in comparison with the old dentures. CONCLUSIONS: Increase of the occlusal vertical dimension in complete denture wearers affects the hyoid bone position and masticatory muscle activity.

The effect of mastication on occlusal parameters in healthy volunteers.

PURPOSE: To assess possible associations between occlusal parameters and comminution of solid food during chewing in a group of completely dentate subjects. MATERIALS AND METHODS: Twenty-five completely dentate volunteers (28 teeth, 14 functional dental units) aged 24-50 yrs, without any complaints of the stomatognathic system participated in this study. An Optosil test was used to estimate masticatory efficiency for 20 and 80 cycles of chewing. An occlusal analysis, using the T-Scan II System, was performed to assess the following occlusal parameters: the distribution of occlusal contacts, the time of occlusion, the chewing platform area before chewing and after 20 and 80 cycles of chewing. RESULTS: The parameters, that were taken into account: i. X50 for 20 and 80 cycles of chewing, ii. the occlusion time, iii. the occlusal contact area. The occlusion time decreased after 20 and 80 chewing cycles (mean TO0=0.28+/-0.07 vs TO20=0.21+/-0.05 s vs TO80=0.18+/-0.05 s, respectively). The mean value of the chewing platform area was 125.12+/-46.5 mm2. CONCLUSION: Prolongation of chewing produces, shortening of the occlusion time while the chewing platform area remains at the same level independent of the number of chewing cycles.

The relationship between masticatory efficiency and the state of dentition at patients with non rehabilitated partial lost of teeth.

UNLABELLED: Factors believed to affect masticatory efficiency include loss of postcanine teeth, bite force, severity of malocclusion, occlusal contact area, body size and oral motor function. THE AIM: to record if there is relationship between masticatory efficiency and the state of dentition at patients whose occlusion has never been rehabilitated. MATERIAL: The study was performed in 22 patients who were missing over 50% of their functional dental units and never used any prosthetic appliances and in 15 healthy completely dentate controls. METHODS: The masticatory efficiency was measured using Optosil test for 20 and 80 cycles of chewing. The occlusal conditions were analyzed by means of the computerized T-Scan II System which registered the maximal force of pressure during the maximal occlusal contacts, the time which passed between the first contact and the maximal force of pressure and the occlusal platform area. RESULTS: It was observed a considerable difference in the integrity of the masticatory system between both groups. The force of pressure on the indicator, chewing platform area and the time from the first contact to the maximal force calculated in T-Scan II System differs significantly between both groups. The value of X50 for 20 and 80 cycles of chewing estimated in Optosil test were statistically significant only for 80 cycles of chewing. CONCLUSION: The severe reduction of the number of functional dental units is caused of the impairment of chewing ability but prolongation of mastication could improve the comminution of hard food.

Affective state and acceptance of dentures in elderly patients.

OBJECTIVE: To examine the relationship between the affective state and acceptance of dentures by elderly patients. SETTING: Dental Outpatient clinics and a residential home for the elderly. Bialystok, Poland. DESIGN: Cross sectional survey of denture wearers. SUBJECTS: One hundred and forty one patients between the ages of 60-94. INTERVENTION: A semi-structured interview, which focused on the patient's self-evaluation of their affective state, and a clinical examination. RESULTS: There was a trend for the negative affects (irritability, boredom, anger, loneliness, helplessness) to relate to denture intolerance and for the positive affects (joy, peace, usefulness) to relate to denture acceptance. CONCLUSIONS: Anger related significantly to intolerance of upper and lower dentures. The relationship of age and gender to the acceptance of dentures in the present sample was not significant.