I-PVC ilungele ukuthotywa kwesisu kunye nokutya kwe-tube yexesha elifutshane;I-PUR impahla ephezulu, i-biocompatibility efanelekileyo, ukucaphuka okuncinci kwi-nasopharyngeal kunye ne-digestive tract mucosa, efanelekileyo kwi-tube yokutya kwexesha elide;