Orthodontics - Common Malocclusion Syndromes

Orthodontic Evaluation
A full orthodontic evaluation includes the following:
• Incisor occlusion
• Canine occlusion
• Premolar occlusion
• Distal premolar/molar occlusion
• Head symmetry
• Number and position of individual teeth
Orthodontic evaluation can be performed at any age. However, maxillofacial development occurs until the age of 18-24 months, and the occlusion may change during that period. The upper and lower jaw may also develop asynchronously in so-called “growth spurts”, thereby giving rise to a temporary, mild and self-correcting malocclusion.

Skeletal vs. dental malocclusions
The main purpose of an occlusal evaluation is to distinguish between a dental malocclusion and a skeletal malocclusion. A skeletal malocclusion is a condition in which the abnormal occlusion is caused by an abnormal bony morphology of the skull; in case of a dental malocclusion, the skull morphology is normal but some teeth are in an abnormal position.
The difference is important because a dental malocclu- sion is generally not considered to be of genetic origin, contrary to a skeletal malocclusion. However, trauma to the developing skull may also cause a skeletal malocclusion. The flow-chart summarizes the criteria used in a comprehensive orthodontic evaluation and the types of malocclusion.

Common malocclusion syndromes in the dog
Rostral crossbite
This term is used for a malocclusion whereby the normal incisor relationship is reversed while the rest of the occlusion is normal. The term level bite refers to a dentition where the incisal edges of the incisors are in full contact. In most cases a palatoversion of the maxillary incisors in present. Many believe that this is a dental malocclusion, caused by the delayed exfoliation of deciduous incisors, which changes the angle of eruption of the permanent teeth. A skeletal malocclusion however can often not be excluded. [...]