Malocclusions

Malocclusion refers to misalignment of the teeth when the jaws are closed, or to an improper alignment between the upper and lower jaws. It encompasses dental malocclusions, where teeth do not align properly, and skeletal malocclusions, where the jaws themselves are not in harmonious relation. Malocclusion is relatively common and can affect chewing, speech, and aesthetics. It may develop during childhood as teeth erupt, or later due to tooth loss, wear, or trauma.

Common classifications derive from Angle's system. Class I denotes a normal jaw relationship with misaligned teeth; Class II indicates an overbite with the upper jaw or teeth protruding (retrognathic mandible); Class III indicates a prognathic lower jaw or underbite. Vertical problems include deep bite and open bite; transverse problems include crossbite where the upper teeth bite inside the lower teeth on one or both sides.

Causes are multifactorial: genetic influences on tooth size and jaw dimensions, environmental factors, habits such as thumb sucking or tongue thrust, early loss of primary teeth, crowding, and trauma. Skeletal malocclusions result from jaw growth discrepancies.

Diagnosis involves clinical examination, dental impressions or scans, photographs, and radiographs. Cephalometric radiographs and panoramic X-rays help assess jaw relationships and tooth position. Treatment planning considers age, growth potential, malocclusion type, and patient goals.

Treatment options include interceptive or preventive measures in children, traditional braces, clear aligners, or removable appliances. Space management and extractions may be used to correct crowding. Functional appliances can influence jaw growth, while severe skeletal discrepancies may require orthognathic surgery in adults or mixed-age patients. Early treatment may reduce long-term complications and improve function and aesthetics.

Prognosis depends on severity and adherence to treatment. Untreated malocclusion can contribute to tooth wear, gum problems, temporomandibular joint pain, difficulties with chewing or speech, and diminished self-esteem. Prevalence varies by population, but mild to moderate malocclusion is common worldwide.