Low intensity pulsed ultrasound combined with guided tissue regeneration for promoting the repair of defect at canines periodontal fenestration in Beagle dogs / 中华口腔医学杂志

ABSTRACT

<p><b>OBJECTIVE</b>To evaluate the effects of low intensity pulsed ultrasound (LIPUS) combined with guided tissue regeneration (GTR) for the repair of the periodontal fenestration defect at the canines in Beagle dogs.</p><p><b>METHODS</b>Four Beagle dogs were used for establishing the periodontal fenestration defect. Sixteen canines of four Beagle dogs were simple randomly assigned into experimental group 1 [LIPUS (60 mW/cm(2), 20 min/d) irradiation + GTR + the periodontal fenestration defect], experimental group 2 [LIPUS (60 mW/cm(2), 20 min/d) irradiation + the periodontal fenestration defect], experimental group 3 (GTR + the periodontal fenestration defect) and control group (the periodontal fenestration defect). Experiments conducted 28 d. The temperature of the gingive's surface of each group was tested every 14 days (analyzed by Wilcoxon rank sum test with SPSS 13.0). The demineralized bone tissue slices of the periodontal fenestration were obtained for histologic staining after 4 weeks treatment.</p><p><b>RESULTS</b>Clinically all the treatment groups healed well. The change of gingive's surface temperature [M(Q)] before and after LIPUS irradiating were 0.225 (0.463)°C (experimental group 1), 0.265 (0.133)°C (experimental group 2), 0.090 (0.115)°C (experimental group 3); -0.175 (0.370)°C (control group). The P value of experimental group 1 and 2 with pre-and post-treatment each time were both 0.027. Histology of the demineralized bone tissue revealed that in experimental group 1, the bone defect was filled with fresh bone-like tissues, proliferatively active osteoblasts and newly formed cementum-like tissues along the defect surface. In experimental group 3, there were more new cementum- and bone-like tissues than in experimental group 2 and control group. In experimental group 2, the new bone collagen was more mature than in experimental group 3 and control group. In control group, there was less growth of new cementum along the notch, and the new bone collagen was immature.</p><p><b>CONCLUSIONS</b>LIPUS combined with GTR may have the potential of promoting the repair of periodontal fenestration defect.</p>