[1] Univ Groningen, Univ Med Ctr Groningen, Div Oncol, Dept Oral & Maxillofacial Surg, Groningen, Netherlands
[2] Univ Groningen, Univ Med Ctr Groningen, Dept Rehabil Med, Groningen, Netherlands
[3] Antoni van Leeuwenhoek Hosp, Netherlands Canc Inst, Dept Head & Neck Oncol, Amsterdam, Netherlands
[4] Univ Coll Hosp, Dept Head & Neck, London, England