Appendix 1. MEDLINE via OVID search strategy

1. exp Endodontics/
2. ("systemic disease$" or (endocrine adj5 disorder*)).mp. [mp=title, original title, abstract, name of substance word, subject heading word]
3. (hyperthyroidism or "padget$ disease" or calcinosis or "gaucher$ disease" or "Turner$ syndrome" or "radiation therapy").mp. [mp=title, original title, abstract, name of substance word, subject heading word]
4. ((tooth adj5 root$) and (injur$ or fracture$ or trauma$ or ankylo$)).mp. [mp=title, original title, abstract, name of substance word, subject heading word]
5. "Tooth Root"/
6. ((pulp$ and infect$) or ((tooth adj5 nerve) and infect$) or periodont$ or orthodont$ or "tooth movement" or ((unerupted or impact$ or erupt$) and (tooth or teeth or molar$ or premolar$))).mp. [mp=title, original title, abstract, name of substance word, subject heading word]
7. ((tumour or tumor) and pressure$).mp. [mp=title, original title, abstract, name of substance word, subject heading word]
8. (2 or 3 or 7) and tooth.mp. and root$.mp. and resorpt$.mp. [mp=title, original title, abstract, name of substance word, subject heading word]
9. (1 or 4 or 5 or 6) and resorpt$.mp. [mp=title, original title, abstract, name of substance word, subject heading word]
10. (8 or 9) and external$.mp. [mp=title, original title, abstract, name of substance word, subject heading word]
11. exp Tooth Resorption/
12. 11 and external$.mp. [mp=title, original title, abstract, name of substance word, subject heading word]
13. 10 or 12
14. (((root adj5 resorpt$) and external$) or (("EARR" or "ERR") and tooth)).mp. [mp=title, original title, abstract, name of substance word, subject heading word]
15. 13 or 14

Appendix 2. Cochrane Oral Health Group's Trials Register search strategy

(((((endodont* or (root AND (fracture* or injur* or trauma* or ankylo*)) or (pulp* AND infect*) or ("tooth nerve" AND infect*) or periodont* or orthodont* or "tooth movement" or ((unerupted or impact* or erupt*) AND (tooth or teeth or molar* or premolar*))) AND resorpt*) OR (("systemic disease*" or "endocrine disorder*" or hyperthyroidism or "paget* disease" or calcinosis or "gaucher* disease" or "Turner syndrome" or "radiation therapy" or ((tumor or tumor) AND pressure*)) AND (tooth AND root* AND resorpt*))) AND external*) OR (("EARR" or "ERR") AND tooth))

Appendix 3. EMBASE via OVID search strategy 

1. exp Endodontics/
2. ("systemic disease$" or (endocrine adj5 disorder*)).mp. [mp=title, abstract, subject headings, heading word, drug trade name, original title, device manufacturer, drug manufacturer name]
3. (hyperthyroidism or "padget$ disease" or calcinosis or "gaucher$ disease" or "Turner$ syndrome" or "radiation therapy").mp. [mp=title, abstract, subject headings, heading word, drug trade name, original title, device manufacturer, drug manufacturer name]
4. ((tooth adj5 root$) and (injur$ or fracture$ or trauma$ or ankylo$)).mp. [mp=title, abstract, subject headings, heading word, drug trade name, original title, device manufacturer, drug manufacturer name]
5. "Tooth Root"/
6. ((pulp$ and infect$) or ((tooth adj5 nerve) and infect$) or periodont$ or orthodont$ or "tooth movement" or ((unerupted or impact$ or erupt$) and (tooth or teeth or molar$ or premolar$))).mp. [mp=title, abstract, subject headings, heading word, drug trade name, original title, device manufacturer, drug manufacturer name]
7. ((tumour or tumor) and pressure$).mp. [mp=title, abstract, subject headings, heading word, drug trade name, original title, device manufacturer, drug manufacturer name]
8. (2 or 3 or 7) and tooth.mp. and root$.mp. and resorpt$.mp. [mp=title, abstract, subject headings, heading word, drug trade name, original title, device manufacturer, drug manufacturer name]
9. (1 or 4 or 5 or 6) and resorpt$.mp. [mp=title, abstract, subject headings, heading word, drug trade name, original title, device manufacturer, drug manufacturer name]
10. (8 or 9) and external$.mp. [mp=title, abstract, subject headings, heading word, drug trade name, original title, device manufacturer, drug manufacturer name]
11. "tooth resorption".mp. [mp=title, abstract, subject headings, heading word, drug trade name, original title, device manufacturer, drug manufacturer name]
12. 11 and external$.mp. [mp=title, abstract, subject headings, heading word, drug trade name, original title, device manufacturer, drug manufacturer name]
13. 10 or 12
14. (((root adj5 resorpt$) and external$) or (("EARR" or "ERR") and tooth)).mp. [mp=title, abstract, subject headings, heading word, drug trade name, original title, device manufacturer, drug manufacturer name]
15. 13 or 14

Filter for EMBASE via OVID:
1. random$.ti,ab.
2. factorial$.ti,ab.
3. (crossover$ or cross over$ or cross‐over$).ti,ab.
4. placebo$.ti,ab.
5. (doubl$ adj blind$).ti,ab.
6. (singl$ adj blind$).ti,ab.
7. assign$.ti,ab.
8. allocat$.ti,ab.
9. volunteer$.ti,ab.
10. CROSSOVER PROCEDURE.sh.
11. DOUBLE‐BLIND PROCEDURE.sh.
12. RANDOMIZED CONTROLLED TRIAL.sh.
13. SINGLE BLIND PROCEDURE.sh.
14. or/1‐13
15. ANIMAL/ or NONHUMAN/ or ANIMAL EXPERIMENT/
16. HUMAN/
17. 16 and 15
18. 15 not 17
19. 14 not 18

Appendix 4. CENTRAL search strategy

1. Exp ENDODONTICS
2. "systemic disease*" or (endocrine NEAR disorder*)
3. hyperthyroidism or "paget* disease" or calcinosis or "gaucher* disease" or "Turner syndrome" or "radiation therapy"
4. ((tooth NEAR root*) AND (injur* or fracture* or trauma* or ankylo*))
5. Exp TOOTH ROOT
6. ((pulp* AND infect*) or ((tooth NEAR nerve) AND infect*) or periodont* or orthodont* or "tooth movement" or ((unerupted or impact* or erupt*) AND (tooth or teeth or molar* or premolar*)))
7. ((tumour or tumor) AND pressure*)
8. ((#2 or #3 or #7) AND tooth AND root* AND resorpt*)
9. ((#1 or #4 or #5 or #6) AND resorpt*)
10. ((#8 or #9) AND external*)
11. Exp TOOTH RESORPTION
12. #11 AND external*
13. #10 or #12
14. ((root NEAR resorpt*) AND external*) or (("EARR" or "ERR") AND tooth))
15. #13 or #14