Evaluation of the Effects of Routine Phase I Periodontal Therapy on Clinical Parameters and Levels of Gremlin-1, CTHRC1, and Tenascin-C in Gingival Crevicular Fluid and Peri-Implant Sulcular Fluid in Individuals With Periodontitis and Peri-Implantitis

The aim of this study is to compare the mechanisms of tissue destruction between natural teeth with periodontitis and implants with peri-implantitis within the same individual, and to evaluate the effects of routine Phase I periodontal therapy (scaling and root planing, and oral hygiene instruction). In this study, the tissue biomarker levels of Gremlin-1, CTHRC1, and Tenascin-C will be investigated. Gingival crevicular fluid (GCF) and peri-implant sulcular fluid (PISF) samples will be collected from subjects concurrently diagnosed with both periodontitis and peri-implantitis.

Inclusion Criteria: * Aged between 18 and 65 years and providing written informed consent. * Systemically healthy (absence of diabetes, osteoporosis, immunological diseases, etc.). * Having a dental implant with prosthetic loading that has been in function for at least 1 year. * No history of periodontal treatment within the last 6 months. * No use of medications that could affect study outcomes (mouthwashes, antibiotics, non-steroidal anti-inflammatory drugs \[NSAIDs\], corticosteroids) in the 3 months prior to sampling. * For the Test Group: Concurrent presence of both Peri-implantitis (bleeding on probing/suppuration, PD \>= 5mm, radiographic bone loss \>= 2mm) and Periodontitis (Generalized Stage III-IV, presence of bleeding on probing and clinical attachment loss) in the same oral cavity. * For the Control Group: Completely healthy periodontal and peri-implant tissues (negative bleeding on probing, PD \