Comparative evaluation of submerged versus nonsubmerged dental implants - A prospective, clinico-radiographic, split-mouth study.

Background: To minimize the risk of impaired osseointegration historically, it has been recommended to insert the implant into the bone (submerged implants) and to allow for submerged healing of 3-6 months in the lower and upper jaw, this conventional technique is advocated. The concept of nonsubmerged healing was introduced in 1988 in which gingival former was placed at the time of implant placement instead of cover screw. The treatment concept of nonsubmerged implant placement enables early implant loading, one surgical procedure only, and a reduced treatment period for the patients.

Aim: The aim of this study was to compare clinical and radiographic outcomes of submerged and nonsubmerged implants.

Materials and method: A prospective split-mouth study of a minimum of 20 bilateral edentulous patients (total of 40 sites) was selected and randomly distributed in two groups: submerged and nonsubmerged implants. Patients were evaluated clinically and radiographically by assessing the patients on clinical parameters which included peri-implant probing depth, mucosal thickness, and width of keratinizing gingiva. Radiographic parameters were crestal bone height-distance between implant shoulder and alveolar crest compared from the bone level, on intraoral periapical.

Results: Our results revealed that the marginal bone loss is statistically significant and has higher values in nonsubmerged implant protocol. All the other clinical parameters were statistically insignificant.

Conclusion: The nonsubmerged implants have reduced the chairside time of the patient, but have a comparatively higher crestal bone loss. Our study concludes that whether it is submerged or nonsubmerged implant placement protocol, under an appropriate oral environment, proper implant selection and methodology both the treatment modalities provide an overall similar success rate.