Dental Caries, Obesity & Overweight, Type 2 Diabetes, Xerostomia
Conditions
Brief summary
This study aims to evaluate the effects of GLP-1 receptor agonists (GLP-1RA) on salivary parameters and oral health in individuals who will use this medication for the first time due to a diagnosis of Type 2 diabetes and/or obesity. The research will be conducted with a longitudinal design including a total of 50 participants. Clinical examinations and saliva analyses will be performed at baseline (month 0), month 3, and month 6. The study will evaluate stimulated and unstimulated salivary flow rates, pH, and buffering capacity, as well as analyze antimicrobial peptide levels (sIgA and beta-defensin-3) and total protein. Participants' oral hygiene and caries activity will be measured using the Silness and Löe Plaque Index (PI), DMFT, and ICDAS-II indices. Additionally, dietary habits and subjective dry mouth symptoms will be monitored through questionnaires. The obtained data will be statistically analyzed by controlling for potential confounding factors such as HbA1c, BMI, CRP, and HOMA index.
Interventions
Patients diagnosed with Type 2 diabetes and/or obesity who are newly prescribed GLP-1 receptor agonists as part of their routine medical treatment. Baseline assessments are performed prior to the first dose, and no drug administration or dosage modification is performed by the researcher.
Sponsors
Kırıkkale University
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
No
Inclusion criteria
* Diagnosed with Type 2 Diabetes Mellitus and/or Obesity. * Newly prescribed a GLP-1 receptor agonist and naive to GLP-1 receptor agonist therapy. * Aged 18 to 65 years * Willing to provide saliva samples and complete study questionnaires.
Exclusion criteria
* Presence of Sjögren's syndrome or known salivary gland disease. * History of radiation therapy to the head and neck region. * Use of antibiotic or antifungal medications within the last 3 months. * Pregnancy, lactation, or active orthodontic treatment. * Presence of other severe systemic diseases or use of medications that affect salivary flow.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in Unstimulated Salivary Flow Rate | Baseline (Month 0), Month 3, and Month 6 | According to the GC Saliva-Check Buffer kit (GC Corporation) instructions, following a visual inspection, unstimulated whole saliva will be collected via the passive drooling/spitting method for 5 minutes with the participant seated upright and head tilted slightly forward. The resting salivary flow rate will be calculated and reported in milliliters per minute (mL/min). |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in Stimulated Salivary Flow Rate | Baseline (Month 0), Month 3, and Month 6 | Stimulated saliva will be collected using the paraffin wax chewing method provided in the GC Saliva-Check Buffer kit (GC Corporation). Participants will chew the paraffin piece for 5 minutes, saliva will be collected into a graduated tube, and the flow rate will be calculated in milliliters per minute (mL/min). |
| Change in Salivary pH | Baseline (Month 0), Month 3, and Month 6 | Resting saliva pH will be determined using the GC Saliva-Check Buffer test kit (GC Corporation). A pH test strip will be immersed in the collected unstimulated saliva sample for 10 seconds and compared against the manufacturer's standardized color chart (ranges: 5.0 to 5.8 \[highly acidic\], 6.0 to 6.6 \[moderately acidic\], and 6.8 to 7.8 \[healthy/neutral\]). Higher pH values indicate a more neutral/healthy oral environment. |
| Change in Salivary Buffering Capacity | Baseline (Month 0), Month 3, and Month 6 | Evaluated using the GC Saliva-Check Buffer test kit (GC Corporation). One drop of stimulated saliva will be dispensed onto each of the three test pads on the strip. After 2 minutes, the color change on each pad will be scored from 0 to 4 (Green=4, Green/Blue=3, Blue=2, Red/Blue=1, Red=0). Scores are summed to give a total buffering capacity score ranging from 0 to 12 (0-5: very low; 6-9: low; 10-12: normal/high). Higher scores indicate better buffering capacity. |
| Change in Dental Plaque Accumulation | Baseline (Month 0), Month 3, and Month 6 | Assessed using the Silness and Löe Plaque Index (PI) on designated index teeth across buccal, lingual, mesial, and distal surfaces. Plaque presence is scored from 0 to 3 (0 = No plaque; 1 = A film of plaque adhering to the free gingival margin; 2 = Moderate accumulation of soft deposits; 3 = Abundance of soft matter within the gingival pocket and/or on the tooth margin). The individual mean score ranges from 0 to 3, where higher scores represent greater plaque accumulation and poorer oral hygiene. |
| Change in Dental Caries Status | Baseline (Month 0), Month 3, and Month 6 | Cumulative caries experience will be evaluated using the World Health Organization (WHO) Decayed, Missing, and Filled Teeth (DMFT) index (ranging from 0 to 28, where higher scores indicate greater cumulative caries experience). Early coronal caries lesions will be detected using the International Caries Detection and Assessment System (ICDAS-II), scoring tooth surfaces from 0 (sound) to 6 (extensive distinct cavity with visible dentin), and the highest ICDAS score per tooth will be recorded for tooth-level analysis. Higher DMFT and ICDAS-II scores represent worse caries experience and active decay. |
| Change in Subjective Dry Mouth Symptoms | Baseline (Month 0), Month 3, and Month 6 | Evaluated using the 5-item Summated Xerostomia Inventory (SXI-D) questionnaire. Participants rate xerostomia-related symptoms over the previous month using a 3-point Likert scale (1 = Never, 2 = Occasionally, 3 = Often). Total scores range from 5 to 15, where higher scores represent more severe subjective dry mouth symptoms. |
| Change in Dietary and Nutritional Habits | Baseline (Month 0), Month 3, and Month 6 | Assessed using a custom, investigator-developed food frequency questionnaire. The questionnaire evaluates daily meal frequency, fluid intake, food preferences, avoidance of dry foods, and consumption frequencies (daily, weekly, monthly) of cariogenic and protein-rich foods. No overall summary score is calculated; responses will be analyzed and reported as categorical consumption frequencies and percentages. |
| Change in Salivary Secretory Immunoglobulin A (sIgA) Levels | Baseline (Month 0), Month 3, and Month 6 | Concentrations of secretory immunoglobulin A (sIgA) will be quantified in saliva supernatants using commercially available enzyme-linked immunosorbent assay (ELISA) kits according to the manufacturer's protocol. Values will be expressed in micrograms per milliliter (µg/mL) and normalized to total protein concentration. |
| Change in Salivary Beta-Defensin-3 Levels | Baseline (Month 0), Month 3, and Month 6 | Concentrations of salivary beta-defensin-3 will be quantified in saliva supernatants using commercially available enzyme-linked immunosorbent assay (ELISA) kits according to the manufacturer's protocol. Values will be expressed in picograms per milliliter (pg/mL) and normalized to total protein concentration. |
| Change in Salivary Total Protein Concentration | Baseline (Month 0), Month 3, and Month 6 | Salivary total protein concentration will be determined using the Bradford protein assay with Coomassie Brilliant Blue G-250 dye and a standard bovine serum albumin calibration curve measured at 595 nm. Results will be expressed in milligrams per milliliter (mg/mL) and used to standardize salivary antimicrobial peptide levels. |
| Change in Serum C-Reactive Protein Levels | Baseline (Month 0), Month 3, and Month 6 | Serum C-reactive protein (CRP) concentrations will be determined from fasting venous blood samples using standard clinical laboratory immunoturbidimetric assays. Values will be reported in milligrams per liter (mg/L). |
| Change in Homeostatic Model Assessment for Insulin Resistance | Baseline (Month 0), Month 3, and Month 6 | Insulin resistance will be evaluated using the Homeostatic Model Assessment for Insulin Resistance (HOMA-IR), calculated with the standard formula: \[fasting glucose (mg/dL) × fasting insulin (µIU/mL)\] / 405. The resulting dimensionless index reflects insulin resistance, where higher values indicate greater insulin resistance. |
| Change in Glycated Hemoglobin (HbA1c) Levels | Baseline (Month 0), Month 3, and Month 6 | Glycated hemoglobin (HbA1c) levels will be measured from venous blood samples using high-performance liquid chromatography (HPLC) or certified clinical laboratory immunoassays standardized to the National Glycohemoglobin Standardization Program (NGSP). Values will be reported as a percentage (%). |
| Change in Body Mass Index | Baseline (Month 0), Month 3, and Month 6 | Body mass index (BMI) will be calculated using standardized anthropometric measurements as body weight in kilograms divided by the square of height in meters (kg/m2). Changes over the 6-month follow-up period will be evaluated and reported in kg/m2. |
Countries
Turkey (Türkiye)
Contacts
CONTACTMerve Haberal, Assist. Prof. Dr.
Outcome results
None listed