Table 1.

Medline Ovid search strategy

1	exp Oral Health//
2.	exp Dentistry/
3.	exp Periodontal Diseases/
4.	exp Tooth Diseases/ 5. or/1–4/
6.	exp “Emigrants and Immigrants/
7.	exp Refugees/
8.	immigrant*.ti,ab./ 9. or/6–8/
10.	exp North America/
11.	exp Europe/ 12. 10 or 11/
13.	5 and 9 and 12/
14.	exp Africa/
15.	african*.ti,ab./ 16. 14 or 15/
17.	13 and 16/
18.	dental health.ti,ab./
19.	dental care.ti,ab./
20.	oral health.ti,ab./ 21. 5 or 18 or 19 or 20/
22.	exp “Emigration and Immigration”/
23.	immigrat*.ti,ab./
24.	refugee*.ti,ab./ 25. 9 or 23 or 24/
26.	16 and 21 and 25/
27.	from 17 keep 18/
28.	from 26 keep 2,8,13–14,16,19,24–25,30,34