# A Systematic Review Comparing Marginal Bone Loss Around Convergent Abutments on Bone‐Level and Tissue‐Level Implants

## TL;DR

This study compares bone loss around dental implants with convergent abutments, finding that tissue-level implants show slightly less bone loss than bone-level ones after one year.

## Contribution

The study systematically isolates the effect of convergent abutments on marginal bone loss in bone-level versus tissue-level implant platforms.

## Key findings

- Tissue-level implants with convergent abutments showed slightly lower marginal bone loss (0.42 mm) compared to bone-level implants (0.53 mm) after one year.
- Differences in bone loss were statistically significant in three studies but considered clinically marginal.
- Both implant types showed minimal bone loss, with a slight advantage for tissue-level implants.

## Abstract

Marginal bone loss (MBL) around dental implants is a critical factor for long‐term success. Convergent abutments have been suggested to improve peri‐implant tissue stability. However, previous reviews have not specifically isolated the role of convergent abutments when comparing bone‐level (BL) and tissue‐level (TL) implant platforms. Therefore, this review aims to clarify whether the implant–abutment connection configuration (BL vs. TL) affects MBL when restored with convergent abutments.

To systematically compare MBL around convergent abutments placed on BL versus TL implants.

This systematic review followed PRISMA guidelines. Electronic databases (PubMed, Scopus, and Web of Science) were searched up to May 2025 for randomized controlled trials (RCTs), cohort, or case–control studies comparing MBL on convergent abutments for BL and TL implants. Two reviewers independently performed screening, data extraction, and risk of bias assessment.

Seven studies (three RCTs and four cohort studies) involving 528 implants were included. Overall, TL implants with convergent abutments showed slightly lower MBL (mean 0.42 mm) compared to BL implants (mean 0.53 mm) after 1 year. Differences were statistically significant in three studies but considered clinically marginal. Risk of bias was moderate to low.

Both BL and TL implants with convergent abutments demonstrate minimal MBL after 1 year, with a slight advantage for TL implants. Further long‐term, high‐quality RCTs are recommended to confirm these findings.