Department of Conservative Dentistry, Semmelweis University, Budapest, Hungary.
J Periodontal Res. 2019 Oct;54(5):499-505. doi: 10.1111/jre.12650. Epub 2019 Mar 13.
Spreading vasodilation is an important means of increasing local blood flow effectively during increased metabolic demands or in case of vascular injury. Our aim was to develop a technique proving the presence of spreading vasodilation in the human keratinized gingiva.
Local vasodilation was evoked by the application of nitric oxide (NO) donor nitroglycerin into a well, fixed 2 mm above the marginal gingiva, in 20 subjects with healthy periodontal tissue. Either 1 or 8 mg/mL nitroglycerin solutions were dropped into the test well at the upper right second incisor, and saline was applied into the control well at the upper left first incisor. The gingival blood flow (GBF) was recorded for 15 minutes by a laser speckle contrast imager below the well and in the surrounding area in the mesial, distal, apical and coronal directions. Gingival thickness was measured by an ultrasonic biometer.
Peak GBF increase was similar after 1 mg/mL and after 8 mg/mL nitroglycerin application in the well (51% ± 12% vs 42% ± 8%) and in the apical region (33 ± 9% vs 55% ± 13%). While the lower dose of nitroglycerin increased GBF only in the apical region around the well, the higher dose induced significant elevations in all surrounding regions, with apical prominence. Hyperaemia lasted 10-14 minutes in the low-dose group whereas it extended beyond the observation period in the high-dose group. Neither the baseline nor the NO-induced peak GBF were correlated with gingival thickness.
The role of the direct effect of NO in the regulation of perfusion was demonstrated in the human gingiva as well as the propagation of local vasodilation to distant, especially apical areas, probably by the mechanism of flow-mediated dilation. This mechanism may have a clinical importance for flap survival or wound healing.
在代谢需求增加或血管损伤的情况下，扩散性血管舒张是有效增加局部血流的重要手段。我们的目的是开发一种技术，以证明人类角化牙龈中存在扩散性血管舒张。
在 20 名牙周组织健康的受试者中，将一氧化氮（NO）供体硝化甘油滴入固定在边缘牙龈上方 2 毫米的井中，以引起局部血管舒张。将 1 或 8 mg/mL 的硝化甘油溶液滴入右上第二前磨牙的测试井中，将生理盐水滴入左上第一前磨牙的对照井中。在井下方和周围的近中、远中、根尖和冠方方向，用激光散斑对比成像仪记录 15 分钟的牙龈血流（GBF）。用超声生物仪测量牙龈厚度。
在井中（51%±12%对 42%±8%）和根尖区（33%±9%对 55%±13%），1 mg/mL 和 8 mg/mL 硝化甘油应用后的 GBF 峰值增加相似。当低剂量的硝化甘油仅增加井周围的根尖区的 GBF 时，高剂量则引起所有周围区域，特别是根尖区的明显升高。低剂量组的充血持续 10-14 分钟，而高剂量组的充血持续时间超过观察期。NO 诱导的 GBF 峰值既不与基线相关，也不与牙龈厚度相关。
在人类牙龈中，NO 的直接作用以及局部血管舒张向远处，特别是根尖区的传播，在调节灌注中起作用，可能通过血流介导的扩张机制。这种机制可能对皮瓣存活或伤口愈合具有临床意义。
