[1] Univ Addis Ababa, Sch Publ Hlth, Coll Hlth Sci, Addis Ababa, Ethiopia
[2] Yekatit 12 Hosp, Coll Med, Plast & Reconstruct Surg Unit, Addis Ababa, Ethiopia
[3] Univ Addis Ababa, Coll Hlth Sci, Sch Med, Dept Surg, Addis Ababa, Ethiopia
[4] Univ Iowa, Coll Dent, Dept Oral Pathol Radiol & Med, Iowa City, IA 52242 USA
[5] Univ Iowa, Coll Dent, Div Biostat & Res Design, Iowa City, IA 52242 USA
[6] Yekatit 12 Hosp, Coll Med, Neonatol Unit, Addis Ababa, Ethiopia
[7] Haukeland Hosp, Plast & Reconstruct Surg Dept, Bergen, Norway
[8] Univ Dundee, Dept Orthodont, Dundee, Scotland