# Eighteen-Year Follow-Up of Bone Sculpting Using the 3A-2B Biological Rule for Immediate and Late Implant Placement With Immediate Loading in Maxillary Fixed Prostheses: A Clinical Report

## TL;DR

This clinical report describes long-term outcomes of a maxillary implant-supported prosthesis using a specific biological rule for bone sculpting.

## Contribution

The paper presents an 18-year follow-up demonstrating the effectiveness of the 3A-2B biological rule in implant placement and bone recontouring.

## Key findings

- Bone recontouring preserved interproximal papillae and gingival contour in the esthetic zone.
- A posterior implant was removed due to peri-implantitis after 18 years of prosthesis use.
- Interproximal contacts opened over time but did not affect patient functionality.

## Abstract

Partial edentulism requiring maxillary rehabilitation with dental implants, whether using segmented or splinted fixed prostheses, often involves three-dimensional tooth position planning. This planning can lead to crown margins that either contact or encroach upon the remaining alveolar bone, a consequence of previous supraeruption. Supraeruption is associated with periodontal growth, where the periodontal ligament and bone develop concurrently with the erupting tooth. For successful outcomes in such cases, it is crucial to perform bone recontouring before implant placement, creating adequate space for the biological width, which is essential for achieving a segmented, implant-supported, fixed prosthesis. In the patient described in this case report, who received eight implants and four fixed partial prostheses, peri-implantitis required the removal of a posterior implant after 18 years of prosthesis use, necessitating retreatment in the corresponding quadrant. Notably, interproximal contacts between the prostheses had opened, likely due to continued craniofacial growth and bone remodeling, although this did not affect the patient's functionality. The recontoured bone and soft tissues maintained their position, preserving both the interproximal papillae and gingival contour in the esthetic zone.