Evaluation of Temporomandibular Disorders During Pregnancy

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.

Primary outcomes

• Change in Graded Chronic Pain Scale - Characteristic Pain Intensity (GCPS-CPI) Score [From first trimester (weeks 8-12) to third trimester (weeks 28-32), approximately 20-24 week]: The GCPS-CPI subscale assesses characteristic pain intensity related to temporomandibular disorders. Scores range from 0 to 100, with higher scores indicating greater pain intensity. The change between the first and third trimester assessments will be evaluated.

Secondary outcomes

• Change in Jaw Functional Limitation Scale-8 (JFLS-8) Score [From first trimester (weeks 8-12) to third trimester (weeks 28-32)]: JFLS-8 assesses jaw-related functional limitation in mastication, mobility, and verbal/emotional expression. Higher scores indicate greater functional limitation.
• Change in DC/TMD Axis I Clinical Findings [From first trimester (weeks 8-12) to third trimester (weeks 28-32]: Clinical findings including maximum mouth opening, lateral/protrusive movement range, palpation pain, and joint sounds, assessed per the DC/TMD short protocol.
• PSS-10 [From first trimester (weeks 8-12) to third trimester (weeks 28-32)]: PSS-10 measures the degree to which situations in one's life are appraised as stressful. Higher scores indicate greater perceived stress.
• Change in Systemic Immune-Inflammation Index (SII) [From first trimester (weeks 8-12) to third trimester (weeks 28-32)]: SII will be calculated from routine complete blood count parameters (neutrophil, lymphocyte, and platelet counts) as: SII = (Platelet count × Neutrophil count) / Lymphocyte count.
• Change in Serum Estrogen and Progesterone Levels [From first trimester (weeks 8-12) to third trimester (weeks 28-32)]: Venous blood samples will be analyzed for serum estrogen and progesterone concentrations, where participants provide additional consent. Hormonal data may not be available for all enrolled participants.

Sex: Female, ages: 18 Years to 40 Years

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

• Minervini G, Marrapodi MM, La Verde M, Meto A, Siurkel Y, Cicciu M, Russo D. The relationship between pregnancy and temporomandibular disorder (TMD) through diagnostic criteria for temporomandibular disorders (DC/TMD) axis II evaluation: a case-control cross-sectional study. BMC Oral Health. 2024 Mar 16;24(1):342. doi: 10.1186/s12903-024-04009-y. PMID 38493079