As an important muscle in TMD, how to examine lateral pterygoid muscle accurately?

Document Type : Original Article


1 Department of Oral and Maxillofacial Surgery, Mansoura University, Mansoura, Egypt

2 Department of Removable Prosthodontics, Mansoura University, Mansoura, Egypt


Objectives: The lateral pterygoid muscle (LPM) is one of the important muscles in TMD patients that needs precise examination.
The aim of this clinical observational study was to compare two examination methods for LPM and to record which method was
better expressing the symptomology of this muscle.
Methods: 72 patients (57 females and 15 males); in whom 127 LP muscles were examined. The patients were selected randomly
from TMJ Clinics of both Oral and Maxillofacial Surgery and Prosthodontics Department, Faculty of Dentistry, Mansoura
University. The patients were randomly and equally divided into two groups. The functional manipulation was carried out first
followed by the intra-oral digital examination for the first group. While for the second group, the intra-oral digital examination
was carried out first. The patients' responses were recorded according to The Verbal Rating Scale (VRS).
Results: There was a poor agreement between the pain scores of functional manipulation test when compared with patients’
clinical pain scores, which was used as the gold standard using Kappa Test. However, very good agreement was achieved
between the digital palpation scores and the patients’ clinical scores (gold standard).
Conclusion: Digital palpation is an effective and a more representable diagnostic modality for evaluating the symptomology
of the lateral pterygoid muscle.