Cementum-analogs using hydroxyapatite binding peptides: Toward periodontal regeneration

NANO 25

Mustafa Gungormus, musgun@u.washington.edu1, Hanson Fong, hfong@u.washington.edu2, Ersin Emre Oren, eeoren@u.washington.edu3, Candan Tamerler, candan@u.washington.edu4, Martha Somerman, somerman@u.washington.edu5, and Mehmet Sarikaya, sarikaya@u.washington.edu1. (1) GEMSEC, Department of Materials Science and Engineering, University of Washington, 302C Roberts Hall, Box 352120, Seattle, WA 98195-2120, (2) Materials Science and Engineering, University of Washington, GEMSEC, Roberts Hall, Box: 352120, Seattle, WA 98195, (3) University of Washington, Seattle, WA 98195, (4) MOBGAM and Molecular Biology-Genetics, Istanbul Technical University, ITU Ayazaga Kampusu Fen Edebiyat Fakultesi, Istanbul, 34469, Turkey, (5) School of Dentistry, Periodontics, University of Washington, Seattle, WA 98195
Periodontal diseases are among the most prevalent of human chronic dental problems which result in tooth loss if left untreated. One major goal of periodontal therapy is the regeneration of the tooth attachment apparatus via new cementum formation and restoration of soft-tissue attachment to the cementum. The presence of an intact cementum and viable cementoblasts and/or periodontal ligament cells plays a critical role in this process. Our previous studies provide evidence that hydroxyapatite binding peptides (HABPs) can serve as nidus for promoting mineral formation on existing tooth structures. Based on these data, we hypothesize that the formation of a cementum-like mineral layer on the damaged root by HABPs will assist to promote the differentiation of progenitor cells into functional cells, such as cementoblasts, osteoblasts, periodontal ligament cells, etc, and thus, result in the regeneration of a functional attachment apparatus. In this study, we have successfully re-mineralized a severely damaged root surface using a in silico-designed HABP. When adsorbed on the root surface, the peptide results in the formation of a crystalline layer of calcium phosphate in a mineralization solution. The newly formed mineral layer is well-integrated with the root surface and remains stable even after physical stresses such as sonication and brushing. The research is in progress to explore the efficiency of the newly formed mineral layer on assisting cell differentiation and functionalization. The ability to have bio-molecules that support mineral formation on tooth surfaces provides a means for not only regeneration of lost periodontal structures, the focus of the studies here, but also will have applications for use as a pulp cap material, for treatment of idiopathic root resorption and for treatment of root surface caries.