Uzunkaya, M., and H. Gundogar. “Evaluation of Periostin Levels in Gingival Crevicular Fluid and Peri-Implant Sulcus Fluid in Patients With Periodontal and Peri-Implanter Disease: A Cross-Sectional Study”. Annals of Medical Research, vol. 26, no. 10, May 2021, pp. 2093-7, http://www.annalsmedres.org/index.php/aomr/article/view/1821.