Oral health conditions and COVID-19: A systematic review and meta-analysis of the current evidence

Prevalence, Features and Degree of Association of Oral Lesions in COVID-19: A Systematic Review of Systematic Reviews

“…After title/abstract screening, three records, one evaluating the risk of virus contamination during minimally invasive surgery [ 19 ], one limiting the investigation to oral manifestations in children [ 20 ] and one reporting lesions observed following COVID-19 vaccination [ 21 ], were excluded. Finally, 12 studies [ 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 ] compliant with the eligibility criteria were included in the present systematic review of systematic reviews.…”

“…Out of the twelve systematic reviews included in the present study, detailed in Table 1 , all resulted to have been published in the English language between 11 September 2020 and 27 April 2022; the full texts were all available, and two authors [ 30 , 32 ] declared funding. Two systematic reviews exclusively comprised case reports and case series [ 27 , 32 ], with one also including letters to the Editor and comments [ 33 ], whilst the remaining nine [ 22 , 23 , 24 , 25 , 26 , 28 , 29 , 30 , 31 ] also considered observational cross-sectional and/or retrospective and/or prospective studies. Three systematic reviews included a meta-analysis [ 23 , 28 , 30 ], and all resulted to be of a critically low quality, except for Doceda et al’s [ 26 ], Nijakowski et al’s [ 28 ] and Orilisi et al’s [ 29 ] studies, characterized by low quality, as per the AMSTAR2 tool assessment.…”

“…Two systematic reviews exclusively comprised case reports and case series [ 27 , 32 ], with one also including letters to the Editor and comments [ 33 ], whilst the remaining nine [ 22 , 23 , 24 , 25 , 26 , 28 , 29 , 30 , 31 ] also considered observational cross-sectional and/or retrospective and/or prospective studies. Three systematic reviews included a meta-analysis [ 23 , 28 , 30 ], and all resulted to be of a critically low quality, except for Doceda et al’s [ 26 ], Nijakowski et al’s [ 28 ] and Orilisi et al’s [ 29 ] studies, characterized by low quality, as per the AMSTAR2 tool assessment.…”

“…The gender ratio of the investigated population was specified in six studies [ 22 , 24 , 26 , 28 , 29 , 32 ], accounting for 4925 subjects, 3156 males and 1769 females (6792 study participants without reported gender). COVID-19 illness severity was defined, differentiating hospitalized and non-hospitalized subjects, in six systematic reviews [ 22 , 25 , 26 , 28 , 29 , 30 ]; in the systematic review conducted by Erbaş et al, 2022 [ 27 ], 76.1% of the overall population was declared to be hospitalized, but it was not definable from the reported findings if the involved subjects were ≥18 years old; therefore, such cases were not presently considered. Ongoing COVID-19 treatment, instead, was described in three studies [ 26 , 28 , 32 ], generally reporting the administration of paracetamol, dexamethasone, chloroquine, antibiotics and antivirals.…”

“…Noteworthy, it may be hypothesized that the presently computed prevalence could be affected by the high number of case reports and series considered in the systematic reviews, thus potentially resulting overestimated, although Fidan et al’s [ 39 ] and Elamrousi et al’s [ 40 ] studies reported prevalence values as high as 65.5% and 90.3%. Such discrepancies may be explained by the exclusion from the present analysis of oral lesions self-diagnosed by means of questionnaires, which were included, instead, in Qui et al’s review [ 30 ], of normal variations, such as fissured and geographic tongue, and of likely pre-existing conditions and diseases, principally represented by Oral Lichen Planus, which were also recorded ( Table 1 ).…”