A Preliminary Study Of The Effect Of Low Intensity Pulsed Ultrasound Combined With Autogenous Bone Graft Or GBR Treatment On Periodontal Tissue Repair In Beagle Dogs

As a safe and non-invasive treatment of orthopedic, Low Intensity Pulsed Ultrasound (LIPUS) was found to have the potential for promoting periodontal tissue repair in preliminary studies. To provide the comparison and initial basis in the further clinical application of LIPUS, we established mandibular premolar classⅡfurcation involvement model and canine periodontal fenestration wounds model, and explored the effect of LIPUS combined with autogenous bone graft or GBR treatment on periodontal tissue repair in beagle dogs.一,The preliminary study of the effect of LIPUS combined with autogenous bone graft on periodontal tissue repair in Beagle dogs'mandibular premolar classⅡfurcation involvement modelThe bilateral mandibular 3rd and 4th premolars of 5 male Beagle dogs were Selected as experimental teeth in our study. The classⅡfurcation involvement models were successfully established by acute boneless, stainless steel wire ligation as well as the feeding of the sticky food with high sugar for 8 weeks. The experimental teeth in each dog were randomly assigned to 4 treatment groups: scaling + ultrasound treatment group (SC+UL), scaling+ultrasound treatment+autogenous bone graft group (SC+UL+ABG), scaling+autogenous bone graft (SC+ABG) and scaling+control group (SC+C). The teeth in SC+UL and SC+UL+ABG group received ultrasound therapy (ISATA 90mW/cm2, 1.5MHz, 200μs, 1KHz) 20 minutes per day for 6 weeks. Result of periodontal clinical examination(GI, PD, AL)showed that every group had improved, but there was no significant difference between groups (P>0.05). According to the volume of new periodontal tissue (alveolar bone, cementum, periodontal ligament), each group was arranged in decreasing order: SC+UL+ABG group,SC+ABG group,SC+UL group,SC+C group(P<0.05);According to the maturity of new alveolar bone, the SC+UL and SC+UL+ABG group showed a higher maturity than SC+ABG and SC+C group.二,The preliminary study of the effect of LIPUS combined with GBR treatment on periodontal tissue repair in Beagle dogs'canine periodontal fenestration wounds model4 canines of 5 male Beagle dogs were selected as experimental teeth in our study. The periodontal fenestration wounds model was established by removing 5×5mm2 buccal alveolar bones in the canine region. The experimental teeth in each dog were randomly assigned to 4 treatment groups: ultrasound treatment group (UL), ultrasound treatment+GBR group (UL+GBR), GBR group (GBR) and control group (C). The teeth in UL and UL+GBR group received ultrasound therapy (ISATA 90mW/cm2, 1.5MHz, 200μs, 1KHz) 20 minutes per day for 4 weeks.Histological analysis: Osteoblasts and cementoblasts were active in UL and UL+GBR groups; the new alveolar bone showed higher maturity; quantitative histological analysis showed that: the volume of new alveolar bone in UL and UL+GBR groups were more than C group (P <0.05), but UL+ GBR compared with GBR treatment group had not see a distinct advantage, this may be associated with a shorter processing time and the source of bone graft materials.In conclusion, this study found that the 90mW/cm2 LIPUS can promote periodontal tissue repair, which may be better when combined with autogenous bone graft. Although this result provided a new idea for the adjuvant therapy of periodontal tissue, the mechanism of LIPUS on promoting periodontal tissue repair remains to be further studied.