The aim of the present study was to detect the transmission rate of ultrasonic low intensity pulsed ultrasound (LIPUS) through polytetrafluoroethylene (PTFE) membrane (Thickness: 0.01 mm) and Bio-Gide collagen membrane, and to provide the basis for the barrier membrane selection on the study of LIPUS combined with guided tissue regeneration (GTR). The ultrasonic (LIPUS, frequency 1.5 MHz, pulse width 200 micros, repetition rate 1.0 kHz) transmission coefficient of the two kinds of barrier membrane were detected respectively through setting ten groups from 10 to 100mW/cm2 every other 10 mW/cm2. We found in the study that the ultrasonic transmission coefficient through 0.01 mm PTFE membrane was 78.1% to 92.%, and the ultrasonic transmission coefficient through Bio-Gide collagen membrane was 43.9% to 55.8%. The ultrasonic transmission coefficient through PTFE membrane was obviously higher than that through Bio-Gide collagen membrane. The transmission coefficient of the same barrier membrane of the ultrasonic ion was statistically different under different powers (P < 0.05). The results showed that the ultrasonic transmittance rates through both the 0.01 mm PTFE membrane and Bio-Gide collagen membrane were relatively high. We should select barrier membranes based on different experimental needs, and exercise ultrasonic transmission coefficient experiments to ensure effective power.
Biocompatible Materials ; Collagen ; chemistry ; Membranes, Artificial ; Permeability ; Polytetrafluoroethylene ; chemistry ; Ultrasonics

In order to make up for the innovation deficiency in the traditional residency training model and the shortcomings of active learning and lifelong learning, evidence-based medicine is introduced into the residency training of dental general practitioners. Theoretical knowledge training of evidence-based medicine is conducted through online course learning. PICO mode is used to conduct evidence-based analysis of clinical cases under the guidance of the instructor, so that trainees can get familiar with the process of evidence-based analysis. Students can finally design and complete the application cases of evidence-based medicine, and teachers give evaluation guidance. Through this process, students can learn and master the knowledge of evidence-based medicine step by step, thus obtaining better teaching results.

OBJECTIVETo study the repair effect of low intensity pulsed ultrasound (LIPUS) irradiating combined with guided bone regeneration (GBR) on the defect of Beagle dog canines periodontal bone.

METHODSFour canine teeth of every beagle dog (8 beagle dogs) were randomly distributed: Group 1 (LIPUS disposal + GBR+ autogenous bone graft group), group 2 (LIPUS disposal + autogenous bone graft group), group 3 (GBR + autogenous bone graft group), blank control group. The model of periodontal bone defect was established in the 1/3 part of the root buccal area. According to the group division, autogenous bone were grafted, group 1 and group 2 were disposed by LIPUS 20 min x d(-1). The intensity of ultrasound were 30 mW x cm(-2). Group 1 and group 3 were injected with Bio-Gide collagen membrane. The beagle dogs were executed at 6 and 8 weeks of the disposal of LIPUS and then Micro-CT test and analysis were conducted to periodontal bone defect area of each group.

RESULTSBy clinical observation, there were different degrees of shrinkages of the area of periodontal bone defect in each group. The Micro-CT test analysis indicated that there was a statistical difference among the number, the thickness as well as the size of bone trabecula of each group (P < 0.05). However, there was no statistical difference (P > 0.05) in terms of bone issue measurement index between 6 to B weeks of each group. Group 1 had the most new bone.

CONCLUSIONLIPUS has the potential to promote the repair of periodontal bone defect. Therefore the combination of LIPUS and GBR may be more conducive to the repair and regeneration of periodontal bone defect.

Animals ; Bone Regeneration ; Bone Transplantation ; Bone and Bones ; Collagen ; Dogs