| Author | Year | Location |
| Abiko, Y., et al. [9] | 1993 | palatal gland |
| Lam, K.Y., et al. [3] | 1998 | plate |
| Stewart, C.J.R., et al. [10] | 2000 | minor salivary gland |
| Aker, H., et al. [11] | 2003 | buccal mucosa |
| Brachtel, E.F., et al. [12] | 2003 | parotid gland |
| Batrani, M., et al. [13] | 2008 | buccal mucosa |
| Siddaraju, N., et al. [14] | 2009 | submandibular gland |
| Goulart, M.C., et al. [15] | 2009 | upper vestibule |
| Kaveri, H., et al. [16] | 2014 | palate |
| Reddy, V., et al. [17] | 2015 | retromolar trigone |
| Brisebois, S., et al. [18] | 2015 | palate |
| Jaishankar, H.P., et al. [19] | 2016 | palate |
| Sreelatha, S.V., et al. [20] | 2017 | buccal mucosa |
| Tandon, A., et al. [21] | 2018 | palate |
| Sharma, S., et al. [22] | 2018 | palate |
| Anjum, R., et al. [23] | 2019 | lip(Low) |
| Urs, A.B., et al. [23] | 2019 | buccal mucosa |