Clinical and radiological evaluation of immediate and delayed single tooth implant placement - 18 Months, prospective, randomized follow-up study.

The aim of the present study was to compare the immediate (Im) and the delayed (De) protocols for placement of single-tooth implants. After allocation to the Immediate and Delayed groups by random, 14 patients were treated with a single-tooth implant with self-threaded internal hex and selective integrated surface (Hi- tec, life care implants) in the anterior or molar region of the maxilla or the mandible on immediate (Im) or 6 months (De) following tooth extraction, respectively. Fourteen patients attended a follow-up visit 18 months after implant placement corresponding to 1 year of loading of the implant restorations. Peri-implant and prosthetic parameters were evaluated clinically and marginal bone levels measured on radiographs. None of the Implant restorations had failed after 1 year of function. Probing pocket depths were reduced by up to 1.5mm on average from the time of loading to the 18 month follow-up and at that time, no significant difference between the Im and De groups was found (4.3 versus 4.2 mm). A statistically significant radiographic marginal bone loss had occurred in the Im group (13.46%) as well as in the De group (15.62%) in the follow-up period. However, a mean marginal bone level of approx. 1.5mm in both groups measured from the implant–abutment junction was found to be acceptable. It was demonstrated that probing pocket depths, papilla fill, width of keratinized mucosa, thickness of peri-implant mucosa and marginal bone levels after 1year of loading of the implant-retained crowns were not influenced by either immediate or delayed implant placement protocols. Furthermore, no severe prosthodontics complications, such as screw loosening or porcelain fractures, arose in this study material. High success rates of single-tooth implants after 1 year of function were achieved using the immediate and delayed single tooth implant placement protocols.