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Malocclusion 617

Malocclusion Client Education
Sheet
VetBooks.ir Diseases and Disorders

BASIC INFORMATION
Caudal crossbite: one or more mandibu-
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lar cheek teeth are buccal to opposing Skeletal malocclusion:
• Abnormal maxillary-mandibular incisor
Definition maxillary cheek teeth when the mouth relationship
An abnormal position of one or more teeth. is closed. • Loss of premolar interdigitation
In dental malocclusion, one or more teeth are Symmetrical skeletal malocclusion: • Incorrect mandibular canine occlusion
in an abnormal position, whereas in skeletal • Mandibular distoclusion (class 2 malocclu- • Jaw length discrepancy (symmetrical or
malocclusion, there is an upper/lower jaw size sion; abnormal rostrocaudal relationship asymmetrical)
discrepancy. between the dental arches in which the • Trauma to soft tissue or other teeth
mandibular arch occludes caudal to its
Synonym normal position relative to the maxillary Etiology and Pathophysiology
Malalignment of teeth arch) • Jaw length, tooth bud position, and tooth size
• Mandibular mesioclusion (class 3 maloc- are independently inherited. Unharmonious
Epidemiology clusion; abnormal rostrocaudal relationship development of the upper and lower jaw
SPECIES, AGE, SEX between the dental arches in which the and maxillary and mandibular teeth results
Malocclusion can be seen in all species and age mandibular arch occludes rostral to its in malocclusion.
groups, and it is usually present from the time normal position relative to the maxillary arch) • Persistent deciduous teeth are associated with
of eruption of the deciduous or permanent Asymmetrical skeletal malocclusion: malpositioned permanent teeth.
dentition. • Maxillary-mandibular asymmetry in a • Significant orofacial trauma at young age
rostrocaudal, side-to-side, or dorsoventral may lead to abnormal development and
GENETICS, BREED PREDISPOSITION direction: malocclusion.
Occlusal development is determined by genetic ○ Rostrocaudal: mandibular mesioclusion • Significant facial trauma at any age may cause
and environmental factors. Most brachycephalic or distoclusion is present on one side of changes in jaw relationships.
cats and dogs show malocclusion due to a the face, but the contralateral side retains
shortened upper jaw. normal dental alignment. DIAGNOSIS
○ Side-to-side: there is loss of the midline
RISK FACTORS alignment of the maxilla and mandible. Diagnostic Overview
• Persistent deciduous teeth ○ Dorsoventral: there is an open bite The diagnosis is based entirely on physical exam
• Orofacial trauma during tooth and jaw (abnormal vertical space between oppos- to identify malpositioned teeth.
development ing dental arches when the mouth is
• Selective breeding for exaggerated head types closed). Differential Diagnosis
• Dental malocclusion versus skeletal
ASSOCIATED DISORDERS HISTORY, CHIEF COMPLAINT malocclusion
• Discomfort and pain can result from maloc- • Abnormal incisor occlusion (show and • Functional (mal)occlusion versus clinically
cluding teeth. breeding dogs) relevant malocclusion (causing discomfort
• Linguoverted mandibular canines can • Abnormal tooth position or pain)
traumatize the hard palate mucosa, leading • Obvious length difference between upper
to oronasal fistula formation. and lower jaws or between left and right Initial Database
• Maloccluding teeth may cause damage Physical exam:
(attrition) to opposing teeth. PHYSICAL EXAM FINDINGS • Look for persistent deciduous teeth.
• Crowded teeth are at risk for development Normal occlusion: • Differentiate between dental and skeletal
of early periodontitis from plaque retention. • The maxillary incisors are positioned rostral malocclusion.
to the mandibular incisors. The crown cusps
Clinical Presentation of the mandibular incisors contact the cingula
DISEASE FORMS/SUBTYPES of the maxillary incisors. TREATMENT
Dental malocclusion: • The mandibular canines are slightly inclined Treatment Overview
• Neutroclusion (class 1 malocclusion; normal labially and bisecting the interdental spaces The goal of treatment is to have a pain-free,
rostrocaudal relationship of maxillary and between the maxillary third incisors and comfortable patient with a functional bite.
mandibular dental arches, with malposition canines. Cosmetic considerations should not play a role.
of one or more teeth) • The maxillary premolars do not contact the
○ Distoversion/mesioversion/linguoversion/ mandibular premolars. The crown cusps of Acute and Chronic Treatment
palatoversion/labioversion/buccoversion: the mandibular premolars are positioned • Extract maloccluding deciduous teeth as
tooth in anatomically correct position in lingual to the maxillary premolars. The early as possible (6-10 weeks of age) if they
the dental arch is abnormally angled in a crown cusps of the mandibular premolars appear to cause discomfort or interfere with
distal/mesial/lingual/palatal/labial/buccal bisect the interdental spaces rostral to the jaw growth.
direction, respectively. corresponding maxillary premolars. • Treatment options for maloccluding perma-
○ Crossbite: malocclusion in which a man- • The mesial crown cusp of the maxillary fourth nent teeth causing trauma to soft tissue or
dibular tooth or teeth have a more labial premolar is positioned lateral to the space other teeth
or buccal position than the antagonist between the mandibular fourth premolar and ○ Extraction
maxillary tooth first molar. ○ Surgical crown reduction and vital pulp
Rostral crossbite: one or more man- Dental malocclusion: therapy
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dibular incisors are labial to opposing • Abnormal positioning of one or more teeth ○ Orthodontic movement (passive or active)
maxillary incisors when the mouth is • No jaw discrepancy • Linguoversion of mandibular canines:
closed. • Trauma to soft tissue or other teeth Verhaert’s rubber ball technique is useful

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