Table 2.
Authors Year | Population | Confounding variables | Sampling | Analysis | |
---|---|---|---|---|---|
Liquid | Buccal hygiene | ||||
Almstahl et al. (23) | 20 pSS 20 HC |
Similar age, gender, nb of teeth Different smoking status, medication |
Sterile cotton swabs on mucosa, dorsum of the tongue, supragingival tooth surfaces, gingival crevice region | Yes (UWS, SWS, nb of teeth, aspect of mucosa) | Selective culture media technique: Streptococci, S. salivarus, F. nucleatum, Prevotella intermedia/Prevotella nigrescens, Candida albicans, S. aureus, Enterics, Enterococci |
Li et al. (24) | 10 pSS : - 6 taking HY - 4 taking HY + PA 10 HC |
Similar age, gender, no smoking, no antibiotics | Sterile cotton swabs on bilateral buccal mucosa | Yes (nb of teeth, aspect of mucosa, UWS, SWS) | The 16S rRNA hypervariable region V1-V3 was sequenced, which resulted in 366 452 raw reads |
van der Meulen et al. (16) | 37 pSS 86 sicca 24 HC matched with pSS patients on sex 103 patients from the general population |
Similar age, smoking status Different treatment, gender |
Sterile cotton swabs | Yes (nb of teeth, oral dryness, UWS, SWS) | The 16S rRNA hypervariable region V4 was sequenced. |
van der Meulen et al. (25) | 34 pSS 34 SLE |
No antibiotics Different smoking status, age, gender |
Oral washing and buccal swab collected at home by patients and frozen | WHO oral Health Questionnaire, Xerostomia inventory questionnaire | The 16S rRNA hypervariable region V4 was sequenced. |
pSS, primary Sjögren’s syndrome; HC, healthy controls; sicca, patients with dryness symptoms; SLE, systemic lupus erythaematosus; UWS, unstimulated whole saliva; SWS, stimulated whole saliva; HY, hydroxychloroquine; PA, prednisone acetas; rRNA, ribosomal ribonucleic acid.