Study No Control Preop level Postop level Time of testing 1) Veltri RW et al 17 - Normal Normal Up to 12 months 2) Ostergaard PA 27 Yes Abnormal Abnormal 30 3) D'Amelio R et al 274 Yes - Normal Not specified 4) Cantani A et al 65 - Normal Abnormal 1 5) Lenander-Lumikari M et al 53 Yes - Normal 48 6) Del Rio-Navarro BE et al 33 - Not specified Normal  Up to > 12 weeks 7) Kirstila V et al  25 - Not specified Normal Up to 6 months 8) Jung KY et al 66 Yes Not specified Normal 1 9) Childers NK et al 25 Yes - Normal 6-14 months

Preop, preoperative; postop, postoperative; SIg, salivary immunoglobulin;

Table 3: Meta-analysis of SIgA levels.