Evaluation of Temporomandibular Disorders During Pregnancy

Evaluation of Temporomandibular Disorders During Pregnancy

This study aims to evaluate how temporomandibular disorders (TMD) - a condition affecting the jaw joint and chewing muscles - change during pregnancy. The same pregnant women will be assessed twice: once in the first trimester (weeks 8-12) and again in the third trimester (weeks 28-32). At each visit, researchers will examine jaw function and pain, and collect blood samples to calculate inflammation markers from routine complete blood counts. Where participants additionally consent, blood samples will also be used to measure hormone levels (estrogen and progesterone). Participants will also complete questionnaires about pain, stress and jaw-related habits. The goal is to better understand whether hormonal and inflammatory changes during pregnancy are associated with the development or worsening of TMD symptoms.

Pregnancy is characterized by significant hormonal, biomechanical, and psychosocial changes. Rising estrogen and progesterone levels may affect connective tissue, joint stability, and pain perception, and estrogen receptors have been identified in temporomandibular joint tissue, suggesting a biological pathway linking pregnancy hormones to TMD symptoms.

This prospective longitudinal cohort study will enroll 60 pregnant women aged 18-40 who are in their first trimester at the time of enrollment. Clinical TMD findings will be assessed using the DC/TMD short protocol; pain and functional limitation will be measured with the Graded Chronic Pain Scale (GCPS) and Jaw Functional Limitation Scale-8 (JFLS-8); psychosocial status will be assessed with the Perceived Stress Scale (PSS-10) and Oral Behaviors Checklist (OBC). Venous blood samples will be drawn at both visits as part of routine complete blood count testing, from which a Systemic Immune-Inflammation Index (SII) will be calculated for all participants. Where participants provide additional consent, blood samples will also be used to measure serum estrogen and progesterone levels; hormonal data may therefore not be available for all enrolled participants. Occlusal relationships (Angle classification) will be recorded as a secondary, exploratory variable. The primary outcome is the change in GCPS pain intensity score between the first and third trimester.

Inclusion Criteria:

• Aged 18-40 years
• Singleton, healthy pregnancy
• Presenting to the Obstetrics and Gynecology outpatient clinic during the first trimester (weeks 8-12)
• No history of systemic rheumatic disease, chronic pain syndrome, or serious psychiatric illness
• No prior orthodontic treatment
• Written informed consent after being informed about the purpose and scope of the study

Exclusion Criteria:

• Prior treatment for temporomandibular disorders (splint, botulinum toxin, surgery, etc.)
• History of maxillofacial trauma or temporomandibular joint surgery
• Systemic rheumatic disease, connective tissue disease, or chronic pain syndrome
• Use of systemic corticosteroids or hormone replacement therapy
• Pregnancy achieved through assisted reproductive techniques (e.g., IVF)
• Refusal to consent to blood sampling or questionnaire administration
• Language barrier preventing understanding and completion of Turkish-language questionnaires