Fixed partial prostheses supported by 2 or 3 implants: a retrospective study up to 18 years

Area of Science:

• Dentistry
• Prosthodontics
• Implantology

Background:

• Fixed partial prostheses (FPPs) are common dental restorations.
• Implant-supported FPPs offer an alternative to traditional bridges.
• Evaluating the long-term outcomes of FPPs based on the number of supporting implants is crucial for clinical decision-making.

Purpose of the Study:

• To compare the long-term clinical performance of fixed partial prostheses supported by either two or three implants.
• To assess survival rates, peri-implant bone levels, and mechanical complications.

Main Methods:

• Retrospective analysis of patients who received implant-supported FPPs between 1985 and 1998.
• Annual clinical follow-ups including stability, peri-implant, and occlusal assessments.
• Radiographic examinations at baseline, 1, 5, and 10 years post-delivery.

Main Results:

• 123 patients with 146 FPPs (63 two-implant, 83 three-implant supported) were followed for a mean of 9.4-9.6 years.
• Survival rates were high for both: 96.8% for two-implant and 97.6% for three-implant supported FPPs.
• No significant differences in bone loss, implant failure, or mechanical complications were observed between the groups, though screw loosening was more common with two implants and porcelain fractures with three.

Conclusions:

• Two-implant-supported fixed partial prostheses demonstrate long-term clinical performance comparable to three-implant-supported FPPs.
• Both configurations offer a high degree of predictability and success in dental implantology.
• While overall outcomes are similar, specific complication patterns may vary between the two designs.