EUROPEAN JOURNAL OF PAEDIATRIC DENTISTRY VOL. 15/2-2014 143 G.A. Scardina, A. Cacioppo, F. Seidita, G. Garofalo*, M. Lotti, P. Messina Department of Orthodontics, University of Palermo, Palermo, Italy *Private Practice, Palermo, Italy e-mail: scardina@odonto.unipa.it ABSTRACT Aim Among the many biological effects which occur during orthodontic movement, we decided to investigate gingival microcirculation. The aim of the study was to evaluate the biological microvascular response to the application of orthodontic force in vivo. Materials and methods Forty patients (case group) between 9-22 years of age (average± DS 12±3.01) were selected for the study (M/F ratio: 20/20). They needed fixed orthodontic treatment due to several types of malocclusion. Forty healthy subjects (control group) were also recruited (M/F ratio 20/20; average age 12 years ± 4.01; Mean±SD =10.04±1.7). A videocapillaroscopic examination was performed on each patient on the buccal alveolar mucosa at the pre-treatment time (t0), 1 month after the beginning of the treatment (t1), after 2 months (t2), after 6 months (t3), and after 12 months (t4). Results Capillary density increases significantly from t0 to t1. Between t1 to t2, t2 to t3 the density underwent another increase. Between t3 and t4 (69.22 ± 3.63) the density showed no increase. In the control group no statistical differences were observed. Conclusion Videocapillaroscopy allows the in vivo evaluation and quantification of the microcirculatory changes consequent to the application of orthodontic force, managing to detect subclinical changes in angiogenesis. In fact, the study revealed an increase in the density of the capillaries which is directly proportionate to the application time of the orthodontic device, i.e. the exogenous mechanical force. This research offers new perspectives for the future of monitoring fixed orthodontic therapy. Evaluation of gingival microcirculation in patients undergoing fixed orthodontic treatment: a pilot study Keywords Orthodontic treatment, Periodontal microcirculation. Introduction Following the application of a force on a tooth, a series of changes are observed in the periodontal tissue and at a metabolic-molecular and microvascular level. During dental movement two areas of the tooth and periodontal complex are considered: a compressed one, usually known as "pressure area" or "resorption area", and a relatively extended one, known as "tension area" or "area of apposition" [Sfondrini et al., 2008; Lanteri, 2002]. In the pressure area an initial collapse of the vessels is produced, which determines an important reduction in the capillary blood flow and periodontal space. During this phase of dental movement we can consider four main effects: deformation of the extracellular matrix (ECM) and hydraulic variations; cellular deformation; cellular activation and differentiation; remodelling of the tissue [Henneman et al., 2008]. The remodelling of the tissue occurs in both soft and hard tissues (mainly bone) [Proffit, 2007; Melsen et al., 2007]. During orthodontic movement, the vascular component has an essential role, supplying nutrients to the cells for their activity, as well as allowing the various metabolic factors to reach the cells. In addition, it allows migration of cells with an amplificatory and regulatory role in the process of tissue remodelling from the vascular system. The aim of this study was to evaluate the gingival microcirculatory modifications in vivo in patients undergoing fixed orthodontic treatment. Materials and methods Forty patients (case group) were recruited for the study (M/F ratio 20/20; average age 12 years ± 3.01; Mean±SD: 11.03±2.8). They needed fixed orthodontic treatment due to different types of malocclusions. Forty healthy subjects (control group) were also recruited (M/F ratio 20/20; average age 12 years ± 4.01; Mean±SD: 10.04±1.7). The criteria for inclusion in the study were as follows: •฀ Good฀general฀health. •฀ Good฀ periodontal฀ health฀ (Silness฀ and฀ Löe฀ Plaque฀ Index฀±1;฀Gingival฀Index±1).