- Overjet refers to the horizontal distance between the incisal edges of the upper and lower front teeth.
- It is commonly known as 'protrusion' or 'buck teeth.'
- Overjet can be measured in millimeters.
- The condition occurs when the upper front teeth protrude beyond the lower front teeth.
- It is a common dental issue observed in both children and adults.
- Overjet can be caused by genetic factors.
- Certain habits, such as thumb sucking or prolonged pacifier use, can contribute to overjet.
- Dental trauma or injury to the front teeth can lead to overjet.
- Malocclusion, or misalignment of the teeth, is another common cause.
- Overjet can also be a result of abnormal growth patterns in the jaws.
- Overjet can affect the appearance and esthetics of the face.
- It may lead to speech difficulties, such as lisping or difficulty pronouncing certain sounds.
- Overjet can increase the risk of dental trauma, as the front teeth are more exposed.
- The condition can impact the proper functioning of the teeth, including biting and chewing.
- Overjet may cause self-esteem issues and psychological distress, particularly in severe cases.
- Orthodontic treatment, such as braces or aligners, can help correct overjet.
- In some cases, extraction of teeth may be necessary to create space for proper alignment.
- Functional appliances, such as headgear or retainers, may be used to guide jaw growth and correct overjet.
- Surgery may be required in severe cases, particularly when the underlying jaw structure needs correction.
- Early intervention and orthodontic evaluation can prevent or minimize the severity of overjet.
Classification
- Overjet is classified under ICD-10 as K07.2.
- It is also classified under ICD-9-CM as 524.26.
- Overjet is categorised under dental anatomy.
- The condition is associated with certain hidden categories, such as articles with short descriptions.
- Overjet is mentioned in pages using infobox medical condition with unknown parameters.
Epidemiology
- Class II Div I malocclusion has an estimated prevalence of 15-20%.
- There is racial variation, with Class II Div I more common in Caucasian populations and lowest in Black racial groups.
- Latin American, Middle Eastern, and Asian populations also have a lower prevalence of Class II Div I.
- The prevalence of Class II Div I malocclusion can vary depending on geographic location.
- The prevalence of Class II Div I malocclusion is higher in certain populations compared to others.
Signs and Symptoms
- Orthodontic treatment can reduce the risk of caries, periodontal disease, and temporomandibular joint dysfunction.
- Individuals with an overjet greater than 3mm are twice as likely to suffer injury to their upper incisors.
- A meta-analysis found that early orthodontic treatment for prominent upper front teeth is more effective in reducing incisal trauma.
- Malocclusion can have a significant impact on an individual's quality of life and self-esteem.
- Prominent upper incisors may be a target for teasing and bullying.
- Untreated overjet can cause chewing and speaking difficulties.
- It can contribute to sleep apnea.
- Overjet can lead to jaw pain and headaches, potentially causing Temporomandibular Joint Disorder (TMD).
- Gum damage can occur when teeth contact the gum.
- Fractured and worn teeth are possible complications.
Treatment
- Class II div 1 malocclusion requires careful timing of referral for optimal treatment options.
- Habit cessation is necessary for successful treatment.
- Early treatment is provided in the early mixed dentition, while late treatment is undertaken in the permanent dentition.
- Early treatment does not necessarily lead to superior outcomes compared to late treatment.
- Functional appliances and Twin Block appliances are commonly used in treatment.
- Timing of referral is crucial for Class II division 1 children.
- Late referral may limit treatment options, particularly growth modification.
- Early treatment in the mixed dentition is no longer recommended for Class II division 1 malocclusion.
- Exceptions for early treatment include a significant risk of incisal trauma or bullying.
- Habits must be stopped before treatment.
- Functional appliances influence muscle groups controlling mandibular position and function.
- They cause skeletal and dental changes, resulting in a decrease in overjet and correction of buccal segment relationship.
- Twin Block appliances are considered the gold standard for functional appliance treatment.
- Twin Block appliances produce a statistically significant reduction in skeletal base discrepancy.
- They also cause beneficial changes to soft tissues.
- Headgear exerts force to the dentition and basal bones through extra-oral traction.
- Headgear can be attached directly to bands on the teeth or to a maxillary splint or functional appliance.
- Headgear primarily affects dento-alveolar structures with some skeletal effect.
- The use of headgear in conjunction with an anterior bite plane can have an additional small effect on mandibular growth.
- Headgear treatment can lead to a reduction in overjet and improvement in skeletal relationship.
- Fixed appliances can be used alone or in combination with extractions or temporary anchorage devices.
- Class II intermaxillary elastics are used with fixed appliances to retract the maxillary teeth against the mandibular teeth.
- Fixed appliances can correct Class II division 1 malocclusion by dental means only.
- Fixed appliances can cause reciprocal mesialization and proclination of the mandibular teeth.
- Fixed appliances are an effective treatment option for Class II division 1 malocclusion.
Overjet is the extent of horizontal (anterior-posterior) overlap of the maxillary central incisors over the mandibular central incisors. In class II (division I) malocclusion the overjet is increased as the maxillary central incisors are protruded.
| Overjet | |
|---|---|
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| Overjet or horizontal overlap. | |
| Specialty | Dentistry |
Class II Division I is an incisal classification of malocclusion where the incisal edge of the mandibular incisors lie posterior to the cingulum plateau of the maxillary incisors with normal or proclined maxillary incisors (British Standards Index, 1983). There is always an associated increase in overjet. In the Class II Division 2 incisal classification of malocclusion, the lower incisors occlude posterior to the cingulum plateau of the upper incisors and the upper central incisors are retroclined. The overjet is usually minimal but it may be increased.
