Perlèche (angular cheilosis) is often caused by the presence of saliva on skin adjacent to mucous membranes. In some cases saliva escapes from the mouth through deep grooves that extend inferolaterally from oral commissures. If the sulci are secondary to a decreased vertical dimension of the lower one third of the face (determined by described measurements), corrective dental measures may be curative. When this approach is not practical and in other cases when the grooves are produced by other causes, the defects can be corrected by use of injections of collagen implant. This has been done successfully in two patients, and angular cheilosis has not reoccurred.