Bond strengths to enamel and dentin with indirect and direct resin composites.

PURPOSE: To investigate the differences in shear bond strengths between indirect and direct resin composites attached to enamel and dentin. MATERIALS AND METHODS: Sixty human molar teeth stored in distilled water since extraction were used in this study. Thirty of the teeth were prepared to form a flat enamel surface ground to 600 grit and 30 of the teeth were prepared to form a flat dentin surface ground to 600 grit. Cylinders constructed from Triad indirect resin composite were bonded to 15 enamel and 15 dentin surfaces and additional cylinders constructed from TPH direct resin were bonded to the remaining 15 enamel and 15 dentin substrates. Bond strengths were determined by shearing the specimens with an Instron testing machine. RESULTS: Mean shear bond strengths observed in this study were: Triad to enamel, 27.64 +/- 7.35 MPa; TPH to enamel, 27.43 +/- 3.37 MPa; Triad to dentin, 21.83 +/- 3.10 MPa; and TPH to dentin, 21.27 +/- 4.85 MPa. Two-way ANOVA demonstrated that significant differences existed between the four test groups and that this difference was primarily related to the surface to which the cylinders were attached (P = 0.000). No significant differences were discovered in shear bond strengths between restorative materials (P = 0.767) or between restorative materials bonded to a specific, common surface (P = 0.891). Turkey's post hoc test demonstrated that the shear bond strength of Triad to enamel was significantly greater than the shear bond strength of either Triad to dentin (P = 0.012) or TPH to dentin (P = 0.005). This test also pointed out that the shear bond strength of TPH to enamel was significantly greater than the shear bond strength of either TPH to dentin (P = 0.007) or Triad to dentin (P = 0.016). Finally, it was noted that the shear bond strength of Triad to enamel was essentially the same as TPH to enamel (P = 1.000) and that the bond strength of Triad to dentin was essentially the same as TPH to dentin (P = 0.990).

Treatment of chronic occlusive arterial disease with pentoxifylline: changes in clinical and haemodynamic parameters.

A prospective study was carried out in 15 patients with peripheral obstructive arterial disease (Fontaine Stage II), with obstructions in the thigh region, to assess the effect of treatment with pentoxifylline on clinical and haemodynamically measurable factors, particularly changes in the post-ischaemic increase in peripheral blood pressure. After a 7-day wash-out period, patients were hospitalized for 1 week and received a daily infusion of 300 mg pentoxifylline plus a 600 mg tablet orally in the evening. They were then treated as out-patients for 2 weeks, receiving 1200 mg pentoxifylline orally per day. Pain-free and maximum possible walking ranges, using a treadmill ergometer, were determined on Days 7, 14, 21 and 28 of the study. Measurements were made at the same intervals, using Doppler ultrasound, and the peripheral resting blood pressure index and post-ischaemic blood pressure index calculated. The results showed significant improvement in both pain-free and maximum walking range after intravenous and oral therapy and this was particularly noticeable in those patients who, before treatment, had a walking range of less than 150 metres: their pain-free range doubled in the first week. There was a slight increase in the resting Doppler blood pressure indices during treatment and a clear, significant increase in the post-ischaemic pressure index 90 and 120 sec after the induced ischaemia ended.