Subsurface microvessels in gingiva of patients with different biotypes

Introduction. Gingival vascularization and biotype play a key a role on the success of periodontal and prosthetic therapy. Aim of the present study was to characterize the distribution and to quantify microvessels in gingiva of patients with different biotypes by capillaroscopy. Materials and methods. Microphotographs (x200) of free and adherent gingiva were taken in correspondence of upper incisors of 22 healthy volunteers. Structure and organization of microvessels were assessed. In 10 randomly selected microphotographs of the attached gingiva of each patient the amount of visible microvessels per mm2 (VMN) were calculated. At the clinical observation study population was divided in four groups according to the biotype (thin, medium, thick and very-thick). Between groups statistical analysis (Kruskal-Wallis test and Mann-Withney test) was performed for data on VMN. Results. At the clinical observation, subjects were distributed among biotype groups as follows: 0 thin, 8 medium (7 females, 1 males), 6 (3 females, 3 males) thick and 8 (4 females, 4 males) very-thick. At the observation with capillaroscopy, microvessels appeared as tortuous capillary loops perpendicular to the gingival margin or as a network running parallel to the profile of the gingival margin. VMN resulted 56.98±5.48 for medium, 51.22±4.54 for thick and 48.21±5.22 for very-thick group and differences were significant (Kruskal-Wallis test p<0.05). VMN in medium group resulted significantly higher than in very thick group (Mann-Withney test p<0.05). Conclusions. Higher amount of microvessels observed in subjects with medium biotype may explain their higher predisposition to develop inflammation and recession of the gingival margin.