[1] Ibb Univ, Fac Dent, Dept Periodontol, Ibb, Yemen
[2] Al Farabi Coll, Dept Restorat Dent Sci, Riyadh, Saudi Arabia
[3] Cairo Univ, Fac Dent, Dept Oral Diag & Periodontol, Cairo, Egypt
[4] Al Farabi Coll, Dept Prevent Dent Sci, Riyadh, Saudi Arabia
[5] Cairo Univ, Fac Med, Dept Med Biochem & Mol Biol, Cairo, Egypt