| HA | hyaluronic acid |
| PPD | pocket probing depth |
| BOP | bleeding on probing |
| CAL | clinical attachment level |
| PI | plaque index |
| GI | gingival index |
| SMDs | standardized mean differences |
| CI | confidence intervals |
| RCTs | randomized clinical trials |
| MeSH | Medical Subject Headings |
| JBI-MAStARI | Joanna Briggs Institute Meta-Analysis of Statistics Assessment and Review Instrument |
| GR | gingival recession |