What is an Overjet in Teeth?

Overjet in Dentistry—An Introduction

Looney Tunes and Merrie Melodies made ‘buck teeth’ iconic with characters like the Goofy Gophers! But the typical protruding two front teeth that made cartoons look funny can be a real dental problem for many. In dentistry, ‘buck teeth’ or forwardly placed front teeth are issues caused by a deranged overjet in teeth. In dental terms, an overjet refers to the horizontal overlap between the upper and lower front teeth when biting. That is, how far ahead your upper front teeth are placed from their lower counterparts [1].

Sometimes, the upper front teeth protrude outward and sit further ahead, causing issues like difficulty in biting, speech problems, jaw discomfort, and even increased risk of tooth damage. This is referred to as an excessive overjet and must be treated on time.

The Causes of Overjet

A normal overjet typically ranges between 1-3 millimetres, but anything beyond this can fall into the category of excessive overjet. The causes of increased overjet are:

• Genetic factors: Protruding upper front teeth often run in the family. If one parent or close kin had a protruding jaw or misaligned upper front teeth, there’s a chance to develop similar traits.
• Childhood habits: Extended thumbsucking, tongue thrusting, pacifier use, and bottle feeding can push the upper teeth forward, leading to a high overjet.
• Prolonged mouth breathing: Mouth breathing during childhood into adolescence, often due to nasal issues, can also influence jaw growth and teeth positioning.
• Teeth malalignment: Misaligned jaws, crowded teeth, or uneven tooth growth can cause the upper teeth to project forward.

Accidents or injuries to the jaw or the front teeth during the growth period can also cause overjet issues later in life.

Symptoms and Impact of Overjet on Oral Health

The ‘buck teeth’ look has been an aesthetic concern for years. However, excessive overjet isn’t just about appearances; it impacts your oral and overall health. Here are the typical symptoms of increased overjet and how they impact life:

• Speech issues: Protruding teeth make it difficult to talk; lisping and mispronounced words are common.
• Biting troubles: Excessive overjets can make it hard to bite and tear slices of bread, meats, fruits, etc. with front teeth.
• Tooth damage: Protruding teeth are more prone to chipping or breaking after a fall or during contact sports like football, boxing, etc. [2].
• Difficulty in closing the mouth: Protruded teeth prevent your mouth from closing worsening mouth breathing issues.
• Jaw Strain: Misaligned teeth can lead to stress on the jaw joints—the temporomandibular joint (TMJ), causing pain and discomfort.
• Gum Problems: Crooked upper front teeth make it difficult to brush and floss the teeth, causing gum problems; prolonged mouth breathing and dry mouth also worsen gum issues.

Complications of Untreated Overjet Issues

Problems with overjet may not pose an immediate concern but can lead to complications with age. If left untreated, it leads to:

• Poor appearance, aesthetic concerns and smile issues impact social life.
• Jaw joining pains or TMJ disorders
• Dry mouth, gum bleeds and cavities
• Tooth abrasions

Excessive overjets are a common orthodontic concern with which people visit the dentist. It is best to visit the dentist early in case of one or more symptoms related to protruding teeth.

Diagnosis

A dentist can diagnose issues of excessive overjet by examining the mouth using diagnostic tools. A typical diagnosis of overjet problems involves the following:

• Consultation: The dentist examines the mouth and discusses the overjet issues with the patient. It is critical to ask questions and clarify any doubts during the consultation.
• X-rays: Lateral cephalograms and 3D digital scans like CBCTs are used to precisely understand the extent of overjet.
• Orthodontic treatment options: Dentists often use visual tools and digital AI software to plan the treatment, preview the outcome and help patients understand their dental procedure thoroughly.

Treatment Options for Overjet

Excessive overjet is not a permanent predicament. Modern dentistry, with the latest tools like dental AI, offers multiple solutions to correct overjet issues [3]. These include:

Early intervention with thorough planning: Dentists typically recommend early screenings and detailed treatment planning. The latest dental tools can accurately plan treatment and design precise appliances such as habit breakers, spacers, and expanders to guide jaw growth and prevent excessive overjets from developing. It is also used for preventive care, such as addressing childhood habits (thumb sucking, pacifier use), which can help reduce the likelihood of developing an overjet.

Orthodontic Treatments: Traditional metal or clear braces are typically used to precisely align the teeth and reduce overjet. Clear aligners are popular among adults for their discreet appearance and effective correction.

Mild overjet issues: In case of moderate overjet problems, dental veneers or ceramic dental crowns can be used to camouflage the buck teeth and compensate for the teeth alignment issues.

Severe cases of overjet: In severe cases, orthodontic braces and aligners may not be sufficient to address skeletal discrepancies. This includes a large, bony upper jaw that is placed too far forward, or the lower jaw is too far back. Orthodontic jaw surgeries can help improve function and aesthetics in such cases.

How to Prevent Overjet Problems

Overjet issues can be avoided when caused by external factors such as childhood habits and teeth malalignments. Some important tips that parents must keep in mind to prevent overjet issues in their children are:

• They must monitor pacifier and bottle use.
• Children must be encouraged to breathe through their nose.
• Routine dental visits are a must.

It is critical to get a routine dental evaluation by 7 years of age to prevent such orthodontic issues.

Takeaway

Overjet doesn’t always cause dental problems. Mildly excessive overjet of teeth is only an aesthetic concern. However, excessive overjet can raise eating, speaking and mouth-breathing concerns. The latest dental tools, like AI and machine learning (ML) can help paediatric dentists, orthodontists and general dentists examine the growth pattern of the jaws, overjet and oral habits closely, prepare accurate treatment plans and help patients and their parents visualise the final treatment outcomes and decide which procedure suits them the best. Overjet corrections improve the smile and chewing ability whilst boosting self-confidence.

FAQ

• Can you live with an overjet?

A deranged overjet of the teeth may not cause immediate health concerns. However, in the long run, excessive overjet worsens mouth breathing and lisping and causes jaw pains, dry mouth, gum inflammation and tooth cavities.

• What is the difference between overjet and overbite?

People often confuse overjet with overbite, but they’re totally different. Overjet is about the horizontal distance between the upper and lower front teeth, while overbite is about how much the top teeth cover the bottom ones.

• How to correct an overjet?

Excessive overjet of the teeth can be corrected with a precisely planned orthodontic treatment. This involves dental appliances, braces, aligners or orthodontic surgery as indicated.

References:

1. Fabian S, Gelbrich B, Hiemisch A, Kiess W, Hirsch C; LIFE Child study team. Impact of overbite and overjet on oral health-related quality of life of children and adolescents. J Orofac Orthop. 2018 Jan;79(1):29-38. English. doi: 10.1007/s00056-017-0114-0. Epub 2017 Dec 19. PMID: 29260241.
2. Schatz JP, Ostini E, Hakeberg M, Kiliaridis S. Large overjet as a risk factor of traumatic dental injuries: a prospective longitudinal study. Prog Orthod. 2020 Nov 9;21(1):41. doi: 10.1186/s40510-020-00341-5. PMID: 33164157; PMCID: PMC7649183.
3. Čirgić E, Kjellberg H, Hansen K. Treatment of large overjet in Angle Class II: division 1 malocclusion with Andresen activators versus prefabricated functional appliances-a multicenter, randomized, controlled trial. Eur J Orthod. 2016 Oct;38(5):516-24. doi: 10.1093/ejo/cjv080. Epub 2015 Nov 4. PMID: 26543061.