# Medial Pterygoid Muscles Penetration by Tubero-Pterygoid Implants: Clinical, Anatomical and Statistical Insights Regarding Temporo-Mandibular Disorders (TMDs)

## TL;DR

This study shows that implants penetrating the medial pterygoid muscle do not cause pain or TMD symptoms, challenging previous assumptions about muscle sensitivity.

## Contribution

The study provides new clinical and statistical evidence that transmuscular implant penetration of the MPM is safe and well-tolerated.

## Key findings

- All patients remained free of pain and TMD symptoms regardless of implant penetration depth.
- Statistical analysis found no link between penetration depth and adverse outcomes.
- Findings suggest that MPM sensitivity may be overestimated in traditional assumptions.

## Abstract

Background: The medial pterygoid muscle (MPM) is frequently implicated in pain and dysfunction in patients with temporomandibular disorders (TMDs), owing to its functional complexity, susceptibility to overload, and rich neuromuscular control. Paradoxically, in patients rehabilitated with tubero-pterygoid implants, whose apices often penetrate or traverse the MPM attachment, no pain, trismus, or TMD-related symptoms are typically observed. Objective: The aim of this study was to evaluate the impact of implant penetration into the medial pterygoid muscle using CBCT and clinical examination after surgery and during follow-up visits. Methods: A retrospective observational study was conducted on 56 patients receiving a total of 116 tubero-pterygoid implants protruding beyond the pterygoid process of the sphenoid bone. Patients were divided into two groups according to implant penetration depth (<2 mm and >2 mm), with a minimum follow-up period of 12 months. Clinical outcomes related to pain, muscle disorders, and TMD symptoms were assessed. Results: Throughout the observation period, all patients remained free of pain, muscular disorders, and signs or symptoms of TMD, regardless of the degree of muscular penetration. Statistical analysis revealed no association between penetration depth and adverse clinical outcomes. Conclusions: The combined clinical and statistical evidence indicates that transmuscular penetration of the MPM by tubero-pterygoid implants is safe and well tolerated. These findings challenge traditional assumptions regarding MPM sensitivity and provide important guidance for surgical planning and maxillary rehabilitation strategies.