Ideal occlusion can be described as the perfect interdigitation of the upper and lower teeth. In the dog, the ideal tooth positions in the arches are defined by the occlusal, inter-arch and interdental relationships of the teeth of the archetypal dog (i.e. wolf). This ideal relationship with the mouth closed can be defined by the following:
Maxillary incisor teeth are all positioned rostral to the corresponding mandibular incisor teeth.
The crown cusps of the mandibular incisor teeth contact the cingulum of the maxillary incisor teeth.
The mandibular canine tooth is inclined labially and bisects the interproximal (interdental) space between the opposing maxillary third incisor tooth and canine tooth.
The maxillary premolar teeth do not contact the mandibular premolar teeth.
The crown cusps of the mandibular premolar teeth are positioned lingual to the arch of the maxillary premolar teeth.
The crown cusps of the mandibular premolar teeth bisect the interproximal (interdental) spaces rostral to the corresponding maxillary premolar teeth.
The mesial crown cusp of the maxillary fourth premolar tooth is positioned lateral to the space between the mandibular fourth premolar tooth and the mandibular first molar tooth.
Normal Occlusion in a Dog:
Normal Occlusion in a Cat:
Normal occlusion in cats is similar to dogs.
Maxillary incisor teeth are labial to the mandibular incisor teeth, with the incisal tips of the mandibular incisors contacting the cingula of the maxillary incisors or occluding just palatal to the maxillary incisors.
Mandibular canine teeth fit equidistant in the diastema between the maxillary third incisor teeth and the maxillary canine teeth, touching neither.
The incisor bite and canine interdigitation form the dental interlock.
Each mandibular premolar tooth is positioned mesial to the corresponding maxillary premolar tooth.
The maxillary second premolar tooth points in a space between the mandibular canine tooth and the third premolar tooth.
The subsequent teeth interdigitate, with the mandibular premolars and first molar being situated lingual to the maxillary teeth.
The buccal surface of the mandibular first molar tooth occludes with the palatal surface of the maxillary fourth premolar tooth.
The maxillary first molar tooth is located distopalatal to the maxillary fourth premolar tooth.