<unk>  (micro- a combining form meaning small + -stomia a combining form meaning mouth = (abnormally) "small mouth") is a clinical feature of many craniofacial syndromes, including Freeman-Sheldon syndrome and Sheldon-Hall syndromes (or distal arthrogryposis multiplex congenita). It may present with whistling-face feature, as well, as in Freeman-Sheldon syndrome. In this syndrome, it impairs alimentation and may require oral commissurotomies, with subsequent revisions, to improve function.
Microstomia
Acephaly 
Microcephaly
Urachal anomalies
Anodontia
Microdontia
Iniencephaly
Breastfeeding difficulties