Longitudinal epidemiological analysis of three decades of TMD populations

OBJECTIVES This study aims to compare the epidemiological data of three cohorts of dysfunctional patients attending to the Clinical Gnathology Service of Policlinico Umberto I University Hospital - Sapienza University of Rome, in order to highlight the salient characteristics of Temporomandibular disorders (TMD) and patients who are affected, and understand their evolution over time. MATERIALS AND METHODS A homogeneous population of 387 dysfunctional patients, belonging to three different decades, consecutively extracted from the medical records in the archive, which contained all their personal, anamnestic and clinical data, was selected. All patients were divided into three homogeneous groups of 129 subjects: GI (1990-1993), GII (2000-2003) and GIII (2010-2013). A descriptive statistical analysis of all the clinical and anamnestic data was performed. RESULTS The female gender (F) is far more interested in the development of TMD, although the study groups of more recent times shows an increasing trend in the incidence on the male one (M): in GI, the patients of M and F sex are respectively 14.84% and 85.16%; in GII are 15.50% and 84.50%; in GIII are 20.16% and 79.84%. Regarding the age, in all three groups the most affected range is between 16 and 40 years: 80% in GI, the 68.26% in GII and the 62.02% in GIII. However, the highest age groups, from 41 to 70 years and over, shows a progressive increase in incidence, from the 90s (GI) to today (GIII): the 17.27% in GI; the 30,16% in GII; the 37.20% in GIII. The most frequent TMDs are the joint diseases (GI: 85%; GII: 54.3%; GIII: 51.2%). The disc displacement with reduction (DDWR) is present in the 44.89% of GI patients, the 40.31% of GII, and the 34.11% of GIII. The disc displacement without reduction (DDWoR) is present in the 40.15% of GI patients, the 13.96% of GII, and in the 17.06% of GIII. GIII shows an increased incidence of muscular pathologies (37.2%) compared to previous decades (GI: 10.2%; GII: 35.6%). The parafunctions are a datum of remarkable incidence in all the study groups, especially in GIII. Clenching is present in the 17.05% of GI, in the 30.23% of GII, and in the 62.8% of GIII. Bruxism is present in the 14.96% of GI, in the 11.63% of GII, and in the 35.66% of GIII. Joint pain is the symptom with higher incidence in all analyzed groups, being reported by the 74.42% of GI, the 79.07% of GII and the 69.77% of GIII. This symptom, whether present on the right, on the left or bilaterally, is mostly referred as moderate/severe by patients of GI, GII and GIII, and shows no remarkable discrepancies between the different decades. Headache is a symptom mostly referred as bilateral, and is the comorbidity most reported all three groups: 45.74% in GI, 57.36% in GII, and 66.67% in GIII. Neck pain occurs mostly bilaterally and is reported by a higher percentage of GIII patients (61.24%), compared to GII (41.87%). CONCLUSIONS The TMD patient, compared to the past, is on average less young and afflicted by painful and chronic diseases, almost constantly accompanied by painful symptoms associated with the purely articular or muscular one, such as headache and neck pain. These features make the dysfunctional patient more complex to be examined, so the specialist need to train properly in order to have a valid diagnostic and therapeutic expertise. CLINICAL SIGNIFICANCE The dysfunctional patient has changed over time several characteristics that must be considered in clinical practice.