Table 5.

Studies using BR for SFN assessment.

Author	Test	Site	Relevant Outcomes	SFN Implication Comments
Mendak et al., 2012 [52]	BR	Unilateral stimulation of lip corner	Significant differences in BR parameters in BMS patients, including prolonged latencies and irregularities. These findings are consistent with SFN, indicating mild sensory and autonomic small fiber involvement.	These findings are consistent with SFN, indicating mild sensory and autonomic small fiber involvement with concomitant central disorders.
Puhakka et al., 2016 [40]	BR	Lingual nerve distribution, bilateral	Longer BR latencies within the lingual nerve distribution in BMS patients compared to controls, although these differences did not reach statistical significance.	Some degree of small fiber involvement but highlights the variability in SFN presentation within BMS.
Kolkka et al., 2019 [59]	BR	Bilaterally lingual nerve distribution	Negative neurophysiological signs in BMS patients, even though there was no statistically significant prolongation of latencies or other typical abnormalities in BR parameters when compared to controls.	The findings are suggestive of Aδ fiber dysfunction supporting SFN. The absence of significant BR abnormalities in the majority of patients indicates that BMS might involve a more complex or varied pathophysiological process

Abbreviations: BMS: burning mouth syndrome; BR: blink reflex; SFN: small fiber neuropathy.