广播电视英语短句 第 84 课：有关智齿-2

They can grow into place normally and never cause a problem. 智齿可以正常地生长出来，不出一点问题。

But often there is not enough room for them in the mouth. 但是口腔里经常会缺少足够的空间以供智齿生长。

They might crowd the other teeth. Sometimes they even push through the gums sideways. 它们可能会挤压别的牙齿，有时，它们甚至从牙龈的侧面挤出来。

An impacted wisdom tooth is one that fails to completely rise through the gums -- the term is erupt. 阻生智齿是指未能从牙龈中完全生长出来的智齿，这里指的是未能完全萌出。

Wisdom teeth that only partly erupt can leave space for bacteria to enter around the tooth. Infection is a risk in these cases. 仅能部分萌出的智齿会在牙齿周围形成间隙，造成细菌聚集，这种情况下易引发感染。