Gingival Biotype and Its Relation with Malocclusion.

Objective: To systematically review the relationship between gingival biotype (GT) and malocclusion.

Methods: The review followed PRISMA standards of quality for systematic reviews and meta-analyses reporting with PROSPERO registration number CRD42020126543. The systematic database search included MEDLINE, Scopus, Embase, PsychINFO, CINAHL, and other key journals; the article search was performed until February 2020. Cochrane's risk of bias in non-randomized studies-of interventions (ROBINS-I) was used to grade the methodological quality of the included studies.

Results: The systematic search identified 105 studies, six studies satisfied the inclusion criteria for eligibility. The study participants ranged from 26 to 200 (total n=812), with a mean of 135. Study participants were aged between 14 and 32 years. Five studies were graded as the moderate risk of bias and one study as low risk of bias. Two studies showed thin GT among individuals with severe crowding compared to mild crowding. Three studies showed a thin GT with a narrow zone of the keratinized gingival width compared to a thick GT. No relationship was found between GT and Angle's classification of malocclusion.

Conclusion: No relationship was observed between Angle's classification of malocclusion and GT. Thin GT was prevalent among individuals with pro-inclination of incisors. Keratinized gingival width was narrow among individuals with thin GT.