1 Subjects: “...water, sanitation and hygiene (WASH)...”

2 Subjects: “...hygienic quality...”

3 Subjects: “...hygiene practices...”

4 Subjects: “...hygiene...”

5 Subjects: “...clean/safe/hygiene factor...”

6 “... of hydrogels. Hydrogels are frequently used for manufacturing contact lenses, hygiene products, tissue...”

7 “... of a dental hygiene regimen, with mechanical removal of plaque and calculus, and, in severe cases...”

8 “... of a dental hygiene regimen, with mechanical removal of plaque and calculus, and, in severe cases...”

9 “... and shaving - away from ‘formal’ medicine and practice - towards new concepts of hygiene and personal grooming...”

10 “... is notoriously difficult to control, while others discuss human hygiene and sanitation. The latter approach...”