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PubMed This is a summary of 13 peer-reviewed journal articles Updated
Genetics · Dentinogenesis Imperfecta

The Genetics and Subtypes of Dentinogenesis Imperfecta

At a Glance

Dentinogenesis Imperfecta (DGI) is an inherited condition usually caused by a DSPP gene mutation that severely weakens teeth. Because DGI Type I is linked to brittle bone disease (Osteogenesis Imperfecta), accurately identifying the specific subtype is a critical first step in care.

Dentinogenesis Imperfecta (DGI) is a genetic condition, meaning it is caused by a change (mutation) in the instructions our bodies use to build teeth [1]. For most people with DGI, the issue lies in the DSPP gene, which provides the blueprint for Dentin Sialophosphoprotein—a protein essential for making strong, hard dentin [2][3].

The “Misfolded Protein” Problem

Inside the cells that build your teeth, there is a specialized “factory” responsible for shaping proteins so they can be sent out to build the tooth [1][2].

In DGI, the mutation causes the DSPP protein to fold into the wrong shape [3]. Because the cell’s quality-control system recognizes the protein is misshapen, it gets “trapped” inside the factory [2][4]. This causes two major problems:

  1. Supply Shortage: The tooth doesn’t get enough functional protein to build healthy, mineralized dentin, leaving the tooth structurally weak [5].
  2. Cellular Stress: The buildup of trapped, misfolded proteins stresses the cell, which can further damage the cell’s ability to create a healthy tooth [2][4].

How It Is Passed Down

DGI follows an autosomal dominant inheritance pattern [1]. This means:

  • One Copy is Enough: You only need one mutated gene from one parent to have the condition [1].
  • 50/50 Chance: If a parent has DGI, there is a 50% chance they will pass the gene to each of their children [1].
  • No “Carriers”: Unlike some conditions where you can carry a gene without having symptoms, in DGI, if you have the gene, you will almost always show signs in your teeth [1].

Understanding the Three Subtypes

Doctors traditionally group DGI into three types based on how it looks and whether it affects other parts of the body.

Type Name / Association Key Feature
Type I OI-Associated Occurs alongside Osteogenesis Imperfecta (brittle bone disease) [6].
Type II Isolated DGI The most common type; affects only the teeth, usually caused by DSPP mutations [7].
Type III Brandywine/Shell Teeth Very thin dentin and large, “hollow” looking pulp chambers (shell teeth) [8].

Why Screening for Type I is Critical

The most important step after a DGI diagnosis is determining if it is Type I. While Type II and III only affect the teeth, Type I is a symptom of Osteogenesis Imperfecta (OI) [9][10].

OI is a systemic condition that makes bones brittle and prone to breaking from very little pressure [11]. Because the dental signs of OI can look exactly like isolated DGI, doctors must look for “red flags” like a history of broken bones, short stature, or a blue/gray tint to the whites of the eyes (blue sclera) [12][11]. Ruling out OI ensures that the patient receives proper care for their skeletal health, not just their dental health [9].

DGI-III: The “Shell Tooth” Variant

Type III is understood as a more severe version of the DSPP mutation [8][7]. Instead of the teeth filling in with extra dentin (as in Type II), the teeth in Type III have very thin walls and huge, hollow centers, making them look like “shells” on an X-ray [8][13]. This type is prone to very rapid wear and early nerve exposure [8].

Common questions in this guide

How is Dentinogenesis Imperfecta passed down in families?
DGI follows an autosomal dominant inheritance pattern. This means it only takes one mutated gene from one parent to inherit the condition, giving a child a 50% chance of having DGI if one parent has it. There are no silent carriers of this gene.
What is the difference between DGI Type I and Type II?
DGI Type II only affects the teeth, making them weak and prone to wear. Type I includes similar dental issues but is actually a symptom of Osteogenesis Imperfecta, a systemic genetic condition that causes brittle and easily broken bones.
Why is it important to screen for Osteogenesis Imperfecta if my child has DGI?
Because the dental symptoms of isolated DGI and Osteogenesis Imperfecta look identical, screening ensures any underlying bone health issues are safely managed. Doctors will look for non-dental red flags like frequent bone fractures, short stature, or a blue tint in the whites of the eyes.
What are "shell teeth" in DGI Type III?
Shell teeth are a specific feature of DGI Type III. In this severe variant, the teeth develop extremely thin outer walls and unusually large, hollow centers. This structural weakness makes the teeth highly vulnerable to rapid wear and early nerve exposure.
What gene mutation causes Dentinogenesis Imperfecta?
Most cases of isolated DGI are caused by a mutation in the DSPP gene. This mutation causes a critical tooth-building protein to fold incorrectly and get trapped inside cells, leaving the resulting teeth structurally weak and poorly mineralized.

Questions to Ask Your Doctor

Curated prompts to bring to your next appointment.

  1. 1.Does our family history or my child's clinical presentation suggest we should test for collagen gene mutations (COL1A1 or COL1A2) in addition to DSPP?
  2. 2.Are my child's dental X-rays showing 'shell teeth' or 'pulp obliteration,' and what does that tell us about their specific subtype?
  3. 3.Should we consider a referral to a geneticist or a bone specialist to definitively rule out Osteogenesis Imperfecta?
  4. 4.Given the 'autosomal dominant' nature of this condition, what are the implications for my other children or future family planning?

Questions For You

Tap a prompt to share your answer — we'll use it plus this page's context to start a tailored conversation.

References

References (13)
  1. 1

    Dental Management of a Child with Dentinogenesis Imperfecta: A Case Report.

    Akhlaghi N, Eshghi AR, Mohamadpour M

    Journal of dentistry (Tehran, Iran) 2016; (13(2)):133-138.

    PMID: 27928242
  2. 2

    A Novel DSPP Mutation in Dentinogenesis Imperfecta Shields Type II: Clinical, Genetic and Stem Cell Perspectives.

    Gao Q, Deng Z, Yang L, et al.

    International dental journal 2025; (75(5)):100937 doi:10.1016/j.identj.2025.100937.

    PMID: 40763686
  3. 3

    Phenotype and molecular characterizations of a family with dentinogenesis imperfecta shields type II with a novel DSPP mutation.

    Du Q, Cao L, Liu Y, et al.

    Annals of translational medicine 2021; (9(22)):1672 doi:10.21037/atm-21-5369.

    PMID: 34988181
  4. 4

    Dentin defects caused by a Dspp-1 frameshift mutation are associated with the activation of autophagy.

    Liang T, Smith CE, Hu Y, et al.

    Scientific reports 2023; (13(1)):6393 doi:10.1038/s41598-023-33362-1.

    PMID: 37076504
  5. 5

    A novel hypothesis based on clinical, radiological, and histological data to explain the dentinogenesis imperfecta type II phenotype.

    Turkkahraman H, Galindo F, Tulu US, Helms JA

    Connective tissue research 2020; (61(6)):526-536 doi:10.1080/03008207.2019.1631296.

    PMID: 31284784
  6. 6

    Case Report: A Novel COL1A1 Missense Mutation Associated With Dentineogenesis Imperfecta Type I.

    Zeng Y, Pan Y, Mo J, et al.

    Frontiers in genetics 2021; (12()):699278 doi:10.3389/fgene.2021.699278.

    PMID: 34249109
  7. 7

    The Modified Shields Classification and 12 Families with Defined DSPP Mutations.

    Simmer JP, Zhang H, Moon SJH, et al.

    Genes 2022; (13(5)) doi:10.3390/genes13050858.

    PMID: 35627243
  8. 8

    A Novel Variant in Dentin Sialophosphoprotein (DSPP) Gene Causes Dentinogenesis Imperfecta Type III: Case Report.

    Wang Y, Xu X, Ding Y, Yuan G

    Molecular genetics & genomic medicine 2025; (13(3)):e70087 doi:10.1002/mgg3.70087.

    PMID: 40040554
  9. 9

    Dentinogenesis imperfecta type II in Swedish children and adolescents.

    Andersson K, Malmgren B, Åström E, Dahllöf G

    Orphanet journal of rare diseases 2018; (13(1)):145 doi:10.1186/s13023-018-0887-2.

    PMID: 30134932
  10. 10

    Dentinogenesis Imperfecta and Caries in Osteogenesis Imperfecta among Vietnamese Children.

    Nguyen HTT, Vu DC, Nguyen DM, et al.

    Dentistry journal 2021; (9(5)) doi:10.3390/dj9050049.

    PMID: 33925433
  11. 11

    A radiological case series of three siblings with osteogenesis imperfecta and shared paternal inheritance.

    Nelwan DA, Ilyas M, Rauf R, et al.

    Radiology case reports 2026; (21(5)):1777-1782 doi:10.1016/j.radcr.2025.06.117.

    PMID: 41717638
  12. 12

    A family with homozygous and heterozygous p.Gly337Ser mutations in COL1A2.

    Udomchaiprasertkul W, Kuptanon C, Porntaveetus T, Shotelersuk V

    European journal of medical genetics 2020; (63(6)):103896 doi:10.1016/j.ejmg.2020.103896.

    PMID: 32081708
  13. 13

    Mutant Dentin Sialophosphoprotein Causes Dentinogenesis Imperfecta.

    Liang T, Zhang H, Xu Q, et al.

    Journal of dental research 2019; (98(8)):912-919 doi:10.1177/0022034519854029.

    PMID: 31173534

This page explains the genetics and subtypes of Dentinogenesis Imperfecta for educational purposes only. Always consult a dentist or genetic counselor for an accurate diagnosis and personalized care plan.

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