The aim of this study is to observe the mechanism of spreading vasoconstriction in human healthy gingiva. Epinephrine solution is applied on the attached gingiva in group "A" and on the surface of the tooth next to the ginvial sulcus in group "B". The different placement of the solution causes different effect in the microcirculation.

Spatial regulation of gingival microcirculation has not been revealed yet. Although this could be an important mechanism to protect gingiva as it is exposed to mechanical, chemical, thermal etc. irritation during whole life. It is especially important during flap surgery. Laser Speckle Contrast Imaging (LSCI) is novel non-invasive method with high spatio-temporal resolution, therefore it allows us to study remote effect of local vasoconstriction such as spreading vasoconstriction in human gingiva.

The epinephrine is a daily used vasoconstrictor material in dentistry and it will be used to trigger remote effect on gingiva. Epinephrine in 1 mg/ml concentration. Solution will be dropped on the gingiva at tooth 12 in a fabricated leakage proof well attached to 2mm above the marginal gingiva in group "A". The solution will be dropped on the surface of tooth 12 next to the sulcus into the well in case of group "B". The changes of the blood flow will be monitor at the test side with surrounding gingival area by LSCI. The control side in each case will be - appropriately to the test side - at tooth 21 with phisiologocal saline.

Inclusion Criteria:

• at least 5 mm keratinized gingiva at the upper front teeth
• general health

Exclusion Criteria:

• pregnancy, breast-feeding
• any medication
• smoking, gingivitis, caries and coronal restoration with insufficient marginal integrity