Comparison of each molar length, of the total molar field length, and the total length of M1+ M2, between wild-type (WT) mice and RSk2-/Y mutant mice with 3 or 4 molars.

M1 size is reduced in mutants with 4 molars both in mandible and maxilla, but only in the maxilla of mutants showing 3 molars. M2 is reduced both in maxilla and mandible whatever the molar mutant phenotype. M3 mesiodistal dimension is reduced only in the mandible, irrespective of the presence of 3 or 4 molars. The total size of the molar field is reduced in the mandible and maxilla in mutant with 3 molars. The total size of the molar field is significantly increased in the maxilla in mutants with 4 molars. The total size of M1+M2 was always reduced when compared to the wild type value. All distances are in millimeters. Significant p-values are shown in bold.M1 : molar 1; M2 : molar 2; M3 : molar 3; ST : supplementary tooth in front of M1; STD : standard deviation; Mutant 3M : mutant with 3 molars; Mutant 4M : mutant with 4 molars; Total : total length of all molars in the molar field.