Evidence of Spreading Vasodilation in Human Gingiva

Study Overview
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Brief Summary
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The aim of this study is to observe the mechanism of spreading vasodilatation on human healthy gingiva. Nitric-oxide donor solutions in lower and higher concentration are used to trigger the vasoactivity.

Detailed Description
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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 vasodilation such as spreading vasodilation in human gingiva. The vasodilatator nitric-oxide (NO) donor will be used to trigger remote effect on gingiva. NO donor solutions will be applied in 1 mg/ml and 8 mg/ml nitroglycerin concentrations. Solution will be dropped on the gingiva at tooth 12 in a fabricated leakage proof well attached to 2mm above the marginal gingiva. The change on blood flow will be monitor at the test well with surrounding gingival area spanning 3 tooth and at the contralateral side by LSCI.

Official Title
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Non-invasive Imaging of Human Gingival Microcirculation: Effect of Nitric Oxide

Conditions
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Nitric Oxide, Vasodilation, Oral Soft Tissue Conditions

Intervention / Treatment
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* Drug: nitroglycerin


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: general health minimum 5 mm keratinized gingiva at upper front teeth Exclusion Criteria: pregnancy and breast-feeding medication (except contraceptives) smoking periodontitis caries insufficient marginal integrity

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 45 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: 8 mg/ml nitroglycerin<br>Higher concentration of NO donor (Nitromint) vs dilution | Drug: nitroglycerin<br>* Vasodilatator solution is dropped on the gingiva.<br>|
| Active Comparator: 1 mg/ml nitroglycerin<br>Lower concentration of NO donor (Nitropohl) vs physiological saline | Drug: nitroglycerin<br>* Vasodilatator solution is dropped on the gingiva.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Blood flow change after application of NO agonist | The change in blood flow will be measured after locally applied nitroglycerin at the site fo application and at the remote sites | 30 min | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Comparsion of the change in blood flow between genders | The maximal blood flow changed assessed in primary outcome will be split into two groups based on gender. The change will be compared between males and females. | 30min | 
| Correlation between the change in blood flow and gingival thickness | The biotpye will be assessed by measurement of gingival thickness by an ultrasonic devices. The correlation between thickness and maximal vasodilation will be evaluated. | 30min | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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spreading vasodilation, gingival microcirculation