The Experimental Study of Immediately Loaded Implants and Deferred Immediate Implant Technique

Objectives:Two-stage implant has the problem of long treatment time and frequent further consultation. The objective of this present study is to evaluate the clinical feasibility of immediately loaded implants and the superiority of deferred immediate implant technique. Methods:36 implants were divided into three groups:¢ñ)immediately implanted and immediately loaded group: implants were placed immediately after extraction and were loaded with crowns instantly; ¢ò)deferred immediate implant: implants were placed 3 weeks after extraction; ¢ó)immediate implant: implants were placed immediately after extraction. Six hybrid dogs were randomly divided into three groups, 6 implants were inserted into posterior region of each dog's mandible according to the above-mentioned three methods, dogs were sacrificed on 1,3,6 months after surgery to observe the manifestation of implants in oral cavity: the specimens were examined by X-ray ,the sections were observed under light and electron microscopes, meanwhile, the quantitative histology was used to calculate bone ingrowth fraction(BIF) and osseointegration index(OI). Results:X-ray examination showed that the OI interface decreased while bone mineral density (BMD) increased; the OI and BIF of 1,3 and 6 month groups increased gradually under light microscope; SEM examination indicated that bone ingrowth was active at interface of 1 month group and 3 month group, dense lamellar bone was observed at the interface of 6 month group. OI and BIF of immediately loaded immediate implant was similar to that of control group ,there was no significant difference between the two groups(P°Ý0.05),however, the OI and BIF of the deferred immediate implant was significantly higher than that of control group (P°Ü0.01). Conclusions:Thus, we got a conclusion from this study that immediately loaded implant was practicable and deferred immediate implant can get better clinical results.