Screw-shaped implants with 3 different surface topographies, evidenced visually as well as numerically with an optical profilometer, were inserted in rabbit bone. After a healing period of 12 weeks, a statistically significant higher removal torque was needed to unscrew screws blasted with 25-microns TiO2 particles and screws blasted with 75-microns particles of AI2O3 compared with screws with a turned surface. The histomorphometric evaluation demonstrated a higher percentage of bone-to-metal contact for implants blasted with 25-microns particles of TiO2 compared with the as-machined implants. A greater surface area of bone in threads was found for the turned screws compared with screws blasted with 25-microns TiO2 particles. In the short-term follow-up, there was a better fixation of implants with an average surface roughness of 0.9-1.3-microns and with a homogeneous surface structure than of implants with an average surface roughness of 0.4 microns and with a clear direction of the surface pattern.

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The aim of this study was to make a comparative evaluation of crown and soft tissue dimensions between implant-supported single-tooth replacements and the contralateral natural tooth. Twenty patients, who had been treated with an implant-supported single-tooth replacement in the esthetic zone of the maxillary jaw and had i) a non-restored contralateral natural tooth and ii) completed the implant-supported crown restoration at least 6 months prior to the scheduled follow-up examination, were included in the study. At the re-examination various variables describing crown form, soft tissue dimensions and soft tissue conditions were assessed. In addition, the patient's overall satisfaction with the esthetic outcome of the implant-supported single crown was scored using a Visual Analogue Scale (VAS). In 12 of the subjects clinical photographs were available from the time of crown insertion for evaluation of longitudinal alterations of the papilla height. The results revealed that, in comparison to the contralateral natural crown, the implant supported crown i) was longer, ii) had a smaller facio-lingual width, iii) was bordered by a thicker facial mucosa, iv) had a lower height of the distal papilla, v) showed a higher frequency of mucositis and bleeding on probing and vi) showed greater probing depths. The longitudinal evaluation of the papillae adjacent to the implant crown showed an improved proximal soft tissue fill at the follow-up examination. The VAS scoring of the patients' satisfaction with the appearance of their single implant-supported restorations revealed a median value of 96% with a range from 70 to 100%. Hence, observed differences in clinical crown height and soft tissue topography between implant-supported single-tooth replacements and the contralateral natural tooth may in most patients be of minor importance for the appreciation of the esthetic outcome of implant therapy.

Recent information suggests that insulin may regulate myosin synthesis in muscle in the direction of the changes observed. Therefore, it is possible that muscle fiber composition abnormalities in insulin-resistant conditions are secondary to hyperinsulinemia. However, the low capillary density, hypothetically, may contribute to insulin resistance.

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Women with NIDDM have high levels of free testosterone and low levels of SHBG. Insulin resistance is closely correlated with these signs of hyperandrogenicity as well as with obesity. Men with NIDDM also have low levels of SHBG and, in contrast to women, low testosterone values. Insulin values correlate negatively with these hormonal factors. Based on the results of experimental work and intervention studies, we suggest that these androgen abnormalities might be causally related to insulin resistance in NIDDM.

LJUNG, THOMAS, BJORN ANDERSSON, BENGT-AKE BENGTSSON, PER BJORNTORP AND PER MARIN. Inhibition of cortisol secretion by dexamethasone in relation to body fat distribution, a dose-response study. Obes Res. 1996;4:277-282. There is now evidence of a hypersensitive hypothalamo-pituitary-adrenal (lIPA) axis in subjects with an elevated waisUhip circumference ratio (WHR), an indicator of the centralization of body fat stores. The activity of the lIPA axis is regulated by central glucocorticoid receptors, whose activity can be tested by the administration of exogenous glucocorticoids, which normally inhibit cortisol secretion.In this study, dexamethasone (dex) was administered in random order in doses of 0.05, 0.125, 0.25 and 0.5 mg at 10 p.rn. with measurements of serum cortisol in the morning (8 a.m.) of this and the following day. The test was performed on 22 apparently healthy men, 40 to 60 years of age, recruited from laboratory personnel, outpatient clinics or advertisements in a newspaper. Eight had a body mass index (BMI) (kglm 2 ) of <25 and 14 of >25. Twelve men had a waist hip ratio (WHR) of <1.0 and 10 men had a WHRof>I.0.Cortisol values at baseline were correlated inversely with WHR and were usually lower in men with a high (>1.0) rather than a low than low «1.0) WHR after dex inhibition. There was apparently no inhibition by dex at 0.05 and 0.125 mg on average in men with a WHR of >1.0. In addition, the inhibition at 0.5 mg dex correlated negatively with the WHR and was significantly lower (p<0.05) in men with a WHR of >1.0 than in men with a WHR of <1.0. None of these differences or relationships was found to be dependent on BMI.It is concluded that men with an elevated WHR experience a decrease in the inhibition of cortisol secretion by dex, It is suggested that this could explain or contribute to the elevated sensitivity of their HPA axis. Furthermore, lower morning cortisol concentrations suggest a change in diurnal secretion patterns.

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