Freestanding and multiunit immediate loading of the expandable implant: an up-to-40-month prospective survival study.

STATEMENT OF PROBLEM: The subject of immediate loading of dental implants has received substantial attention, although it appears to conflict with the basic principles of dental implant therapies developed and established over the past 20 years. Clinicians would welcome the use of a reliable, immediate-loading implant system.

PURPOSE: The purpose of this study was to evaluate the effectiveness of an expandable implant design for immediate and delayed loading and for freestanding and multiunit situations.

MATERIAL AND METHODS: Two hundred eighty-six immediate-load Sargon implants were placed in 75 patients during a 40-month period. Of the 273 implants that survived, 81 were placed into fresh extraction sockets and immediately loaded, 162 were placed into healed sites and immediately loaded, and 30 were delay loaded. Some implants that had failed to remain stable after immediate loading became stable and osseointegrated after the load was removed and their expansion mechanisms were reactivated.

RESULTS: The overall survival rate during the 40-month period was 96.0% in the maxilla and 94.8% in the mandible. Implants placed in fresh extraction sockets showed a 98.9% survival rate. Healed sites showed a 93.9% survival rate. Immediate loading of 52 fresh extraction socket implants in the maxilla showed a 100% survival rate during the evaluation period.

CONCLUSION: Within the limitations of this study, it was shown that the feature of mechanical expandability may provide operators some control over implant stability during the vulnerable period after immediate loading of single, freestanding implants.