Skip to content
knowrare
HealthSignal
Your condition community

Living with Fused mandibular incisors

A very rare dental difference in which two front baby teeth on the lower jaw are joined together.

Understanding Fused mandibular incisors

Fused mandibular incisors is a very rare dental condition in which two lower front baby teeth are joined together.

Two front teeth on the lower jaw, which are normally separate, form joined together in the baby (primary) teeth. It often occurs along with missing teeth (hypodontia) and a higher chance of the tooth's inner pulp being exposed. Features may be noticed from childhood into adulthood.

Signs & symptoms

Symptoms vary from person to person. GARD lists these among the most common:

  • Differences in the teeth (abnormal dentition)
  • Teeth coming in earlier than expected

Not everyone has every symptom. GARD's list comes from the Human Phenotype Ontology.

Diagnosis

  1. Talk with your doctor

    Share the symptoms you've noticed, when they started and your family health history. Notes and photos can help.

  2. See a specialist

    Specialists who may be involved include genetic specialists and gum, teeth and mouth specialists.

  3. Ask which tests can help

    Your care team will decide which exams and tests can confirm the diagnosis.

Care & treatment

Care team
Genetic specialists (geneticists); Gum, teeth and mouth specialists (odontologists)
Expert care
Ask about multidisciplinary care centers for rare conditions
Treatment
GARD doesn't list specific treatments for this condition. Your care team will tailor care to your symptoms.
Research
Clinical trials and observational studies may be options. See the research section below.

General information, not medical advice. Your care team makes the decisions.

Everyday life

Living with a rare condition is easier with support.

  • Connect with rare disease patient organizations for support
  • Keep notes on symptoms, changes and questions for appointments
  • Ask about patient registries that help research
  • Look into financial aid and travel resources for care visits
Bring these questions to your next doctor visit
Should I see a pediatric dentist or a dental specialist?
Does a missing tooth (hypodontia) go along with the fused teeth?
What can be done to protect the fused teeth from pulp exposure?

Quick facts

Symptoms usually startfrom Childhood to Adulthood
InheritanceAutosomal Dominant

Changes in genes (also called variants) cause this condition. It is inherited in an autosomal dominant way, which means one changed copy of a gene can be enough to cause it.

Genetic

Also known as: "double tooth"; fusion of mandibular incisor teeth

Patient organizations

Rare-disease groups that can help

Source: NIH GARD · Fused mandibular incisorsGARD ID 2419 · GARD page updated September 2026 · Plain-language summary by Know Rare; editorial review pending. General information, not medical advice.

You are more than your diagnosis

Perspectives from people navigating life with Fused mandibular incisors.

Explore the Fused mandibular incisors blog

Explore research for Fused mandibular incisors

Explore actively recruiting Fused mandibular incisors studies with HealthSpark.

HealthSpark

Find actively recruiting studies for Fused mandibular incisors with HealthSpark. Share your city to explore research near you.

  • Recruiting studies from ClinicalTrials.gov
  • Share your city to look for research near you
  • Eligibility is confirmed by the study team

Powered by HealthSpark, our AI chat helper

I can help you find recruiting Fused mandibular incisors studies. Enter a ZIP code, address or city below and I'll look within 50 miles.

Powered by HealthSpark, our AI chat helper · Study information from ClinicalTrials.gov · Eligibility is confirmed by the study team.

Get Signals for Fused mandibular incisors

Stay in the loop with community stories and updates from medical researchers.

HealthStoryfor Fused mandibular incisors

Create a living journal that talks back

HealthStory evolves private journaling with a living AI journal that talks back and asks thoughtful questions, helping you capture your Fused mandibular incisors experiences more deeply and prepare for better conversations with your doctors and care team.

Start your journal

Your journal is private. Sharing your story publicly is a separate choice, made with Share your story above.