The MICH concept for long-term implant stability.

This review introduces a structured, evidence-based concept for achieving long-term soft tissue and prosthetic stability with tissue-level implants. It synthesises current literature and clinical guidelines to highlight four core pillars, namely mucosal seal, individualised implant positioning, collar design optimisation and harmonised integration of soft tissue and restoration, and is thus referred to as the MICH concept. Particular emphasis is placed on the biological importance of adequate peri-implant mucosal thickness (≥ 2 mm) for maintaining a stable soft tissue seal and reducing the risk of marginal bone loss. The review further highlights the anatomical and biological foundations of supracrestal tissue height adhesion, supporting the clinical significance of personalised implant placement and collar design for maintaining peri-implant health. By addressing both biological and prosthetic aspects, the MICH framework advances beyond the established PROS concept for bone-level implants that encompasses the principles of platform switching, restorative abutment design, optimal (internal conical) connection and subcrestal implant placement, offering clinicians clear guidance tailored to the unique challenges posed by tissue-level systems. Developed in accordance with the Appraisal of Guidelines for REsearch & Evaluation standards, this structured approach aims to support interdisciplinary planning and promote long-term stability of both hard and soft tissues around tissue-level implants.