Various classification schemes have been devised in the last 70 years for cleft lip and palate, but few have received widespread clinical acceptance. Four of the more accepted schemes are highlighted below.
The Davis and Ritchie classification divides cleft lip and palate into 2 groups, which subdivided into the extent of the cleft as follows:
The Veau classification system divides the cleft lip and palate into 4 groups, which are as follows and illustrated in the image below:
The Kernahan and Stark classification highlights the anatomic and embryonic importance of the incisive foramen that is formed during weeks 4-7 gestational age (GA). The secondary palate forms the roof of the mouth from the incisive foramen to the uvula during weeks 7-12 GA (see the image below).
This system provides a graphic classification scheme using a Y- configuration, which can be divided into 9 areas, as follows (see also the image below) :
The International Confederation of Plastic and Reconstructive Surgery classification system uses an embryonic framework to divide clefts into 3 groups, with further subdivisions to denote unilateral or bilateral cases, as follows:
Koul introduced a method for documenting all types of cleft lip and cleft palate for data storage and communication. This "Expression System" incorporates the actual words for the anatomical structures affected by clefts and can describe accurately and easily, without the need for consulting reference materials, the location and extent of both typical and atypical clefts. The Expression System overcomes several limitations of previous cleft registration methods, and its simplicity and precision benefits all those involved in the care of patients with cleft lip/palate by furthering the interdisciplinary and intradisciplinary approach.