Study on the effect of ultrasonic irrigation in deactivating and eliminating the endotoxin in the root canals of chronic periapical periodontitis / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To study the effect of ultrasonic irrigation in deactivating and eliminating the endotoxin in the root canals of chronic periapical periodontitis.</p><p><b>METHODS</b>10 maxillary premolars with 2 root canals extracted because of serious chronic periapical periodontitis were opened conventionally and prepared with modified double-flared technique with apical foramen sealed. 30 microL 3% H2O2 solution was introduced into each root canal and 2 minutes ultrasonic vibration was given. Samples were taken before and after ultrasonic vibration. 10 maxillary premolars with 2 root canals of chronic periapical periodontitis of 10 patients in clinic were selected. The root canals of them were instrumented as above, followed by 2 minutes ultrasonic irrigation with asepsis distilled water. Samples were taken before, after root canal preparation and after ultrasonic irrigation. The endotoxin activity of them was tested by kinetic turbidimetric limulus test.</p><p><b>RESULTS</b>The mean endotoxin activity of extracted premolars before ultrasonic vibration was 4.069 EU x mL(-1) while after ultrasonic vibration it was 16.410 EU x mL(-1). There was great statistical difference between them (P < 0.01). The endotoxin activity after ultrasonic vibration was significantly higher than that of before vibration. The clinically mean endotoxin activity before, after root canal preparation and after ultrasonic irrigation were 44.860, 4.099, and 0.116 EU mL1 respectively. There was great statistical difference between the endotoxin activity before and after root canal preparation (P < 0.01). After the preparation, the endotoxin activity droped obviously. There was great statistical difference between the endotoxin activity before and after ultrasonic irrigation (P < 0.01). After ultrasonic irrigation, the endotoxin activity droped obviously.</p><p><b>CONCLUSION</b>Under the condition of simulating clinical work presence, the ultrasonic irrigation can not intensify the effect of the root canal rinse solution in deactivating the endotoxin of infected root canals, but it may intensify the effect of the root canal rinse solution in eliminating the endotoxin of infected root canals.</p>

Effects on Helicobacter pylori reinfection in gastric mucosa by two oral plaque control methods / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the reinfection rate of Helicobacter pylori (H. pylori) in gastric mucosa by two measures of oral plaque control on patients, and to demonstrate the necessity and better method of plaque control on those patients.</p><p><b>METHODS</b>148 patients suffered gastritis or gastroduodenal ulcer were assigned into test group 1 (54 patients), test group 2 (55 patients) and control group (39 patients). 13C-urea breath test proved that there were no H. pylori in their gastric mucosa. Daily plaque control was used in test group 1, oral professorial interventions were added into test group 2, neither daily plaque control nor oral professorial interventions was conducted in control group. All patients were conducted 13C-urea breath test again after half a year to determine the reinfection rate of H. pylori in gastric mucosa.</p><p><b>RESULTS</b>5 patients were eliminated because of stopping mouthwash in the test group 1, 8 patients failed to control dental plaque in the test group 2. The infection rates of H. pylori in gastric mucosa of test group 1, test group 2 and control group were 67.3%, 19.1%, 82.1%, respectively. The infection rate of H. pylori of test group 2 was lower significantly than that in control group and test group 1 (chi2=33, P<0.05; chi2=31.06, P<0.05). There were no significant difference between test group 1 and control group (chi2=2.43, 0.1<P<0.25).</p><p><b>CONCLUSION</b>Dental plaque is an important source of gastric H. pylori reinfection. Dental plaque control procedures should be performed in the treatment of gastric disease correlated with H. pylori. The method of mixing professional dental plaque control and solution of mouthwash was better.</p>