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ORPHA:99789

Dentin dysplasia type I

medium confidenceSubtype of disorder

Also known as: DD-I · DTDP1 · Radicular dentin dysplasia

Publications

1,774

89.1th percentile

Trials

0

Interventional, condition-specific

Researchers

746

Distinct authors in sample

Gene link

SMOC2

Strong

Readiness

3/6

Stages with a signal

Clinical definition (Orphanet)

Dentin type I (DD-I) is a rare form of dentin (DD) characterized by sharp conical short roots or rootless teeth.

How rare: 1-9 / 100 000 — about one to nine people per hundred thousand.

Orphanet entry

Cross-references

Joined from Mondo / Orphanet. MeSH labels may enter searches; UMLS / OMIM / NCIT are stored for reference.

Additional Mondo synonyms (3)

dentin dysplasia type I · dentin dysplasia, type i, with microdontia and misshapen teeth · radicular dentin dysplasia

Research stages

Trial readiness signals

Where this condition sits on an open-data research pipeline — not how close a treatment is, and not medical advice. Empty stages often mean “not in these databases under this Mondo ID,” not “impossible.”

3/6 stages with a signal

No matched interventional trial; the gene is known and literature exists — preclinical or natural-history work may still be the practical next step.

  1. Gene identifiedPresent

    Strong — SMOC2

  2. LiteraturePresent

    1,774 matched papers (1,396 in last 10 years) Source

  3. Phenotype characterisedPresent

    11 HPO annotations (e.g. Pulp obliteration; Microdontia; Enamel hypoplasia) Source

  4. Animal modelNot found

    No Alliance genotype “model of” associations via Monarch for these Mondo IDs

  5. Orphan designationNot found

    No FDA or EMA orphan-drug designation matched this disease via UMLS or preferred name Source

  6. Interventional trialNot found

    No matched interventional trial under our ClinicalTrials.gov rules

Biology

Genes and phenotypes

Gene–disease validity from GenCC, plus phenotypes and animal models joined from Monarch Initiative via Mondo ID — not a clinical diagnosis aid.

Do we know what causes it?

Yes — we know a specific gene responsible (SMOC2).

GenCC classification: Strong.

Phenotypes (Monarch / HPO)

11

Associated phenotypes · MONDO:0007436

  • Pulp obliteration
  • Microdontia
  • Enamel hypoplasia
  • Taurodontia
  • Periapical bone loss

Showing 5 of 11 — open Monarch for the full list.

Animal models (Monarch / Alliance)

None returned for this Mondo ID. Empty here is not proof that no model organism work exists under another name or gene.

Monarch fetch 2026-07-29

Therapies

Designations, candidates, and chemicals

FDA OOPD and EMA orphan designations, Open Targets clinical candidates, and CTD chemical associations via MyDisease.info. These never change the interventional-trial headline.

Orphan designation (FDA · EMA)

No designation matched this disease via UMLS or preferred name on the FDA OOPD mirror or EMA orphan register. Absence here is not proof that none exists under another wording.

Open Targets candidates

No drugs or clinical candidates returned for this Mondo ID on Open Targets.

CTD chemicals (MyDisease.info)

No CTD chemical associations returned for this Mondo ID.

Literature

Is anyone studying this?

1,774

1,774 papers have been published on this condition. That is a real research literature — still far smaller than common diseases (breast cancer: over 700,000 papers). Median papers in the last 10 years for a rare disease in this dataset (publications denominator n=3967) is 59.

1,774 papers since the earliest indexed year in this search — median last-10-year count for a rare disease in this dataset is 59 (publications denominator n=3967).

1,396 in the last 10 years · medium confidence · 89.1th percentile (publications denominator)

Phrase hits: 140 · MeSH hits: 1

Open Europe PMC search

Who's working on it?

746

Distinct author names in 141 sampled papers — named people below.

Who's working on it?

No interventional trial matched this name; these authors publish on it in the sampled literature — a practical starting point for contact.

  1. 01
    Chen D11 papers · 2026

    Department of Medical Genetics, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China.

    Papers in Europe PMC
  2. 02
    Xiong F8 papers · 2021

    Department of Medical Genetics, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China Guangdong Genetic Testing Engineering Research Center, Guangzhou, China.

    Papers in Europe PMC
  3. 03
    Bloch-Zupan A5 papers · 2024

    1] Faculty of Dentistry, University of Strasbourg, Strasbourg, France [2] Reference Centre for Orodental Manifestations of Rare Diseases, Pôle de Médecine et Chirurgie Bucco-Dentaires, Hôpitaux Universitaires de Strasbourg, Strasbourg, France [3] Institute of Genetics and Molecular and Cellular Biology (IGBMC), Inserm U964, CNRS-UdS UMR7104, Illkirch, France.

    Papers in Europe PMC
  4. 04
    Xu X5 papers · 2025

    Department of Medical Genetics, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China Guangdong Genetic Testing Engineering Research Center, Guangzhou, China.

    Papers in Europe PMC
  5. 05
    Li L4 papers · 2023

    BGI-Wuhan Clinical Laboratory, BGI-Shenzhen, 430074, Wuhan, China.

    Papers in Europe PMC
  6. 06
    Liu Y4 papers · 2023

    Department of Genetics, Jiangxi Maternal and Child Health Hospital, 330006, Nanchang, China.

    Papers in Europe PMC
  7. 07
    Lu T4 papers · 2023

    Center of Craniofacial Orthodontics, Department of Oral and Cranio-Maxillofacial Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.

    Papers in Europe PMC
  8. 08
    Wang Y4 papers · 2025

    Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL 35294, USA.

    Papers in Europe PMC
  9. 09
    Chen Z3 papers · 2024

    State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration, Key Laboratory of Oral Biomedicine Ministry of Education, Hubei Key Laboratory of Stomatology, School & Hospital of Stomatology, Wuhan University, Wuhan, China. zhichen@whu.edu.cn.

    Papers in Europe PMC
  10. 10
    Duncan WK3 papers · 1994

    Department of Pediatric Dentistry, University of Mississippi School of Dentistry.

    Papers in Europe PMC

Clinical research

Is a treatment being tested?

0

interventional trials for this specific condition

No interventional trial testing a treatment matched this specific condition name on ClinicalTrials.gov (observational studies and pan-disease registries are listed separately when present).

Data as of 11 September 2026 · last trial check 11 September 2026

No matched interventional trials. This is true for 77.2% of diseases in the trials denominator (5501 of 7126). Here are the researchers publishing on it.

medium confidence · 38.6th percentile (trials denominator)

Recruiting interventional trials

From the matched ClinicalTrials.gov set

No interventional trial testing a treatment was found for this specific condition name on ClinicalTrials.gov.

Broader category dentin dysplasia also has no matched interventional trial. See who's working on it — people publishing on this disease are often the practical next contact when no trial is listed.

Broader category: dentin dysplasia

0

Interventional trials for the parent category, exclusive of NCT IDs already counted above. Eligibility for this subtype is not guaranteed.

Parent-category matching found a broader label but no interventional trials under it. How we count trials.

Other registries (secondary)

Broader net from EU CTIS, ISRCTN, and ICTRP when available — deduped against ClinicalTrials.gov IDs already counted above. Dual-model LLM relevance gates what we keep. These rows are not added to the interventional headline.

raw 1 · after dedupe 1 · already on CT.gov 0 · kept 0 · parent 0 · uncertain 1 · dropped 0 · fetched 2026-07-30

Source notes: ictrp: Error: ICTRP public search unavailable (WHO portal is SPA-only; SOAP needs partnership). Tried: https://apps.who.int/tri

No secondary-registry studies passed dual-model relevance for this condition name (after dedupe).

Uncertain / not reviewed (1)

Where to find support

Condition-specific patient organisations, when Orphanet lists them, are on the disease’s Orphanet page. We also link umbrella groups that support undiagnosed and ultra-rare families.

Orphanet entry for Dentin dysplasia type I — check Associations / patient organisations on that page.

India — NPRD

Last verified 2026-07-26

This ORPHAcode is not on our curated NPRD list (direct or Mondo-parent match). That does not decide clinical eligibility; families in India should ask a notified Centre of Excellence about current coverage.

Hand-curated for this project. ORPHAcode mappings are best-effort and may be incomplete or imprecise for umbrella categories. Parent (Mondo) matches mean the policy lists a broader category — confirm eligibility with a Centre of Excellence. Financial entitlements summarised from public policy statements and may change. This is not official government guidance.

How we counted this

Europe PMC query (preferred label + any corrected label + Orphanet and Mondo exact synonyms, stoplisted; unioned with resolved MeSH labels when available). UMLS / OMIM / NCIT cross-references are stored on the overview but are not added to the query string.

("Dentin dysplasia type I" OR "DTDP1" OR "Radicular dentin dysplasia" OR "dentin dysplasia, type i, with microdontia and misshapen teeth") OR (MESH:"[OBSOLETE] Opalescent dentin" OR MESH:"Dentin dysplasia, type 1") OR ("SMOC2" OR "SMOC2 syndrome" OR "SMOC2-related")

Run this search on Europe PMC

MeSH descriptor terms unioned into the query: [OBSOLETE] Opalescent dentin; Dentin dysplasia, type 1

ClinicalTrials.gov query (quoted phrases + MeSH via query.cond, plus recall-expansion terms when used):

"Dentin dysplasia type I" OR "DTDP1" OR "Radicular dentin dysplasia" OR "dentin dysplasia, type i, with microdontia and misshapen teeth" OR "[OBSOLETE] Opalescent dentin" OR "Dentin dysplasia, type 1"

Study-type breakdown: 0 interventional · 0 observational · 0 expanded access. Only interventional studies enter the trial headline.

Parent-category trials query:

"dentin dysplasia"

Query health: ok — strategies attempted: phrase, mesh; with hits: phrase, mesh

Run this search on ClinicalTrials.gov

Synonyms dropped by stoplist: DD-I

Confidence reasoning

  • Preferred label is multi-word and distinctive
  • 1 synonym(s) dropped by stoplist (may under-count)
  • No label/synonym collisions with other diseases in this corpus

Ingested 2026-07-27T06:17:08.800Z