The Research Of Osseointegration Of Implant-bone Interface On Immediate Loading Of Immediate Implant In Periodontally Compromised Dogs

Objective: To investigate the osseointegration of implant-bone interface of immediateloading of immediate implant on mandibular premolar area in periodontitis modeldogs.Method: To establish experimental periodontitis model in8beagle dogs by ligature oftheir premolar teeth in bilateral mandibular with steel wire and high-carbonhydrate diet.The periodontal examination of experimental tooth were recorded on1,2,3,4weeksand periodontitis model were established in4weeks. In fifth week, to control thedental plaque on all teeth, supragingival and subgingival scaling was implementedrespectively. After5weeks, the third and fourth anterior molar in bilateral mandibularof each dog was extracted simultaneously. And then, one DIO dental implant (diameter:3.8mm, length:10.0mm) which connect to base stations was implanted immediately inthe perfect location of each extraction socket(diameter:3.8mm, length:6.0mm).Vertical loads on dental implant were carried out by vertical-type loading within24hours after the surgery. The loading force on four dental implants of each dog was5N,10N,15N,0N. The loading frequency and time was2Hz,15minutes a day. The4dogs were executed after loading4and8weeks. General observation, imagingobservation and hard tissues and morphology observation were performed afterspecimens been prepared.Results:①Bones around implants showed absorption, especially group15N, whichbecome Ⅱ-Ⅲ loose degree.②The parameters of BMD in group of5,10N had difference with the control group with significance (P<0.01) in different loading cycles.③The parameters of BV/TV, Tb.Th, Tb.N, Po in group of5,10N had difference withthe control group with significance (P<0.01) in different loading cycles. The group of5,10N had obvious differences between the control group in the part of SMI (P<0.01).④The figure of tissue slices showed that, group5,10N have more fresh bone thancontrol group in different loading stage, space between fresh bone and Implant threadin group5,10N are narrower than the control group at8weeks.Conclusion: The osteogenesis and bone-reconstruction of loading group is morepositive than contral group in different loading cycles, which indicated that Properloading force after immediate implanting in periodontitis model dogs can obtain wellosseointegration on implant-bone interface.