Less marginal bone loss around bone-level implants restored with long abutments: A systematic review and...

Area of Science:

• Dental Implantology
• Periodontology
• Prosthodontics

Background:

• The 'one abutment at one time' protocol is crucial for implant success.
• Bone-level implants are widely used, but abutment selection impacts outcomes.
• Understanding biological outcomes related to abutment length is essential for clinical practice.

Purpose of the Study:

• To systematically review and compare biological outcomes of bone-level implants restored with long versus short abutments.
• To evaluate the influence of the 'one abutment at one time' protocol on these outcomes.

Main Methods:

• A systematic search was conducted in five major databases (PubMed, EMBASE, Web of Science, Scopus, CENTRAL) up to January 2023.
• Eight randomized controlled trials were included, analyzing marginal bone loss, bleeding on probing, and probing pocket depth.
• Statistical analyses used mean difference (MD) and risk ratio (RR); quality was assessed using ROB Tool 2, ROBINS-I, and GRADE.

Main Results:

• Longer abutments on bone-level and platform-switched implants showed reduced marginal bone loss at 6 months and 1 year.
• Subgroup analysis indicated no difference in marginal bone loss when the 'one abutment at one time' protocol was applied (p=0.973).
• Bleeding on probing and probing pocket depth showed similar, favorable results in both groups.

Conclusions:

• Longer abutments appear to be a beneficial choice for mitigating early marginal bone loss in bone-level implants.
• The timing of abutment placement did not significantly alter marginal bone loss in this analysis.
• Clinical decisions regarding abutment length should consider potential benefits for early bone stability.