# Bone‐Level Versus Tissue‐Level Titanium Dental Implants: A Comparative Cross‐Sectional Study

## TL;DR

This study compares bone-level and tissue-level titanium dental implants, finding similar survival rates but lower peri-implantitis with 3.3mm tissue-level implants.

## Contribution

The study identifies implant diameter and mucosal thickness as key factors influencing peri-implantitis risk in long-term implant therapy.

## Key findings

- BL and TL implants showed comparable survival rates and peri-implant disease prevalence.
- 3.3mm TL implants had significantly lower peri-implantitis rates compared to BL implants.
- Higher plaque scores and smoking increased the risk of peri-implantitis, while greater mucosal thickness reduced it.

## Abstract

To compare the long‐term survival rate and prevalence of peri‐implant diseases between bone‐level (BL) and tissue‐level (TL) titanium implants. The secondary objective was to assess the effect of implant diameter and other risk indicators of peri‐implant diseases on the outcomes of implant therapy.

Adult patients with at least one non‐molar implant‐supported prosthesis (ISP) were included in the study. Relevant clinical and radiographic outcomes, along with patient‐related, anatomical, surgical and prosthetic‐related factors, were analysed.

A total of 266 patients and 336 ISPs were included after a mean follow‐up of 11.2 ± 1.5 years. Implant survival rates at the implant level were 99.4% and 98.2% for BL and TL implants, respectively. The prevalence of peri‐implant health, mucositis and peri‐implantitis was comparable between BL (21.1%, 67.5% and 11.4%, respectively) and TL implants (20.5%, 70.5% and 9.0%). Implants with a diameter of 3.3 mm showed lower peri‐implantitis rates (7.2%) compared to those with 4.1 mm (13.3%; p = 0.02). Notably, 3.3 mm TL implants exhibited a significantly lower peri‐implantitis rate (4.8%) than BL implants (9.6%; p < 0.001). Multilevel regression at the implant level showed that parafunctional habits (OR = 0.33, 95% CI: 0.12–0.91) and greater mucosal thickness (OR = 0.44, 95% CI: 0.32–0.60) were cross‐sectionally associated with decreased odds of mucositis, whereas higher plaque scores were cross‐sectionally associated with increased odds (OR = 1.29, 95% CI: 1.03–1.61). Age was cross‐sectionally associated with peri‐implantitis (OR = 0.96, 95% CI: 0.93–0.99), higher plaque score (OR = 1.45, 95% CI: 1.11–1.90), larger implant diameter (OR = 2.98, 95% CI: 1.19–7.45) and smoking (OR = 4.54, 95% CI: 1.42–14.5), while greater mucosal thickness (OR = 0.17, 95% CI: 0.08–0.37) was cross‐sectionally associated with a reduced risk of developing this condition.

BL and TL implants at non‐molar sites exhibited comparable survival and peri‐implant disease rates. However, TL implants with 3.3 mm diameter showed lower peri‐implantitis rates. A higher plaque score increased the risk of both mucositis and peri‐implantitis, whereas smoking was a strong risk indicator for peri‐implantitis. Greater mucosal thickness was protective against both conditions.