It is formed by the combination of the liquid drop where cleaning between the teeth in the surface between the teeth was combined with the shearing stress which is formed by the effect which the air drives liquid membrane 18,20 forms the ru collision shearing stress on the living thing membrane between the teeth. With depth of the tooth between space it decreases the shearing stress which is formed by the liquid drop, with depth between the teeth it increases the shearing stress which on the other hand, is formed the air by the liquid membrane which is driven. The gap power which is combined at least is equal to the shearing stress which is necessary in order to remove the living thing membrane from the surface between the teeth.歯間クリーニングは、歯間表面において液膜18,20をエア駆動させる効果により生成されたずれ応力と組み合わせられた、歯間生物膜上の或る衝突ずれ応力を生成する液滴の組み合わせにより生成される。液滴により生成されたずれ応力は、歯間空間の深さとともに減少し、その一方で、エア駆動された液膜により生成されたずれ応力は、歯間の深さとともに増大する。組み合わせられたずれ力は、歯間表面から生物膜を除去するために必要なずれ応力と少なくとも同等である。
