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Abnormalities of the Teeth

Steven Chussid D.D.S.Director, Division of Pediatric Dentistry

Abnomalities of teethEnvironmental alterationsDevelopmental alterations

Environmental alterationsEffects on tooth structure development

LocalizedSystemic

Postdevelopmental structure lossDiscoloration of teethLocalized disturbances of eruption

Local factors associated with enamel defects

TraumaLocal infectionIrradiation

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Enamel hypoplasia Enamel hypocalcification

Systemic factors associated with enamel defects

InfectionsMedicationsInherited diseasesMetabolic disordersMalnutritionBirth-related trauma

Enamel hypoplasia

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Enamel hypoplasia Enamel hypoplasia

Enamel hypoplasia-Rickets Fluorosis

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Fluorosis Postdevelopmental tooth lossTooth wear

AttritionCaused by tooth to tooth contact

AbrasionCaused by external agent

ErosionCaused by chemical process

Internal resorptionExternal resorption

Attrition Attrition

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Erosion-Bulemia Internal resorption

Internal resorption External resorption

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External resorption Environmental discolorationExtrinsic

BacteriaIronTobaccoFood and beverageRestorative materialsMedications

Iron stain Environmental discolorationIntrinsic

Erythropoietic porphyriaHyperbilirubinemiaTraumaMedications

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Erythropoietic porphyriaAutosomal recessive disorder of porphyrinmetabolism that results in increased synthesis and excretion of porphyrinsDiffuse discoloration of dentition resultsTeeth appear red-brown and exhibit a red fluorescence when exposed to UV lightProphyrin present in enamel and dentin of deciduous teeth so discoloration worseOnly dentin of permanent teeth affected

Erythropoietic porphyria

HyperbilirubinemiaExcess levels of bilirubin in bloodBilirubin can accumulate in interstitial fluid, mucosa, skin and developing teethCauses include-

Erythroblastosis fetalisA hemolytic anemia of newborns secondary to blood incompatibility

Biliary atresiaA sclerosing process of the biliary tree

Premature birthInternal hemorrhage

Hyperbilirubinemia

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Trauma Tetracycline stain

Tetracycline stain Fluorosis

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Localized disturbances of eruption

AnkylosisNatal teeth

AnkylosisCessation of eruption after emergence occuring from an anatomic fusion of tooth cementum or dentin to alveolar boneEtiology unknown-trauma, local change of metabolism, thermal irritation, and genetic predisposition have been suggestedCan occur at any age but is clinically most evident when it develops during first two decades of lifePeak prevalence- 8-9 years of age

AnkylosisReported prevalence of clinically detectable ankylosis- 1.5% to 9%Primary molars are most commonly involved teeth with most cases in mandibleRadiographic findingsSound on percussionTreatment considerations

Ankylosis

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Ankylosis Ankylosis

Ankylosis Natal teethUsually prematurely erupted primary teethPresent at birthPrevalence- 1 in 2000Neonatal teeth erupt within first month85% are lower incisors, 11% maxillary incisorsTreatment

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Natal teeth Natal teeth

Natal teeth Natal teeth

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Developmental alterationsNumberSizeShapeStructure

Developmental alterationsNumber

HypodontiaLack of development of one or more teeth

AnodontiaTotal lack of tooth development

HyperdontiaDevelopment of an increased number of teeth

HypodontiaCommon dental anomaly

3.5%-8% (excluding third molars)Female predominance about 1.5:1Uncommon in primary dentition (<1%)About 20-23% of population missing third molarsAfter third molars, second premolars and laterals most frequent

Syndromes associated with hypodontia

Ectodermal dysplasiaChondroectodermal dysplasia (Ellis-van Creveld)Incontinentia pigmentiProgeriaDownHallermann-StreiffRiegerCrouzonsAlbright hereditary osteodystrophy

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Hypodontia Hypodontia

HypodontiaHypodontia-Ectodermaldysplasia

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HyperdontiaPrevalence of supernumerary teeth is about 1%-3% (higher rate in Asians)Single tooth hyperdontia represent 75%-85% of casesMore common in permanent dentitionAlmost 90% in maxillaMaxillary incisor region most common site then 4th molars,premolars and caninesIf multiples, usually in mandibular premolar region

Syndromes associated with hyperdontia

Cleidocranial dysplasiaOral-Facial-DigitalCraniometaphyseal dysplasiaApert

Hyperdontia Mesiodens

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Hyperdontia Hyperdontia

Cleidocranial dysplasia Paramolar

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Developmental alterationsSize

MicrodontiaMacrodontia

MicrodontiaTeeth are smaller that usualRelative microdontia=macrognathiaDiffuse true microdontia is uncommon but may occur in Down syndome and pituitary dwarfismPrevalence of isolated microdontia is between 1% and 8%Maxillary lateral incisor most frequently affected

Microdont- peg lateral Microdont- peg lateral

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Microdont MacrodontiaTeeth are larger than usualRelative macrodontia=micrognathiaDiffuse involvement very rareHas been noted in association with pituitary gigantism and hemifacialhyperplasia

Macrodontia Developmental alterationsShape

GeminationFusionConcrescenceTalon cuspDens evaginatusDens invaginatusTaurodontismDilaceration

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Double teethGemination and fusion

May have very similar clinical appearanceHigher frequency in anterior and maxillary regionsRate is about 0.1% in permanent dentition and 0.5% in deciduousBilateral cases more infrequentEtiology unknown but trauma has been suggestedTreatment considerations

GeminationSingle joined or enlarged tooth in which tooth count is normal when anomalous tooth is counted as oneResult from single tooth bud????

Gemination Gemination

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Gemination FusionSingle joined or enlarged tooth in which tooth count reveals missing tooth when anomalous tooth is counted as oneUnion of two separate tooth buds?

Fusion Fusion

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Fusion ConcrescenceUnion of two adjacent teeth by cementum aloneMay occur before or after eruptionSeen most commonly posterior and maxillary regionsEtiology believed to be trauma or overcrowdingTreatment considerations

Concrescence Talon cuspWell-delineated additional cusp on the surface of an anterior tooth and extends 1/2 the distance from CEJ to incisal edgeVast majority on lingual surfacePrevalence studies vary from <1% to 8% 3/4 found in permanent dentition, most commonly maxillary lateral then centralIn deciduous dentition, maxillary central most common siteHas been associated with other dental anomaliesTreatment considerations

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Talon cusp Dens evaginatusAlso known as a central tubercleA cusplike elevation located in the central grooveTypically occurs in permanent mandibularpremolarsUsually bilateralRare in whites with higher prevalence in Asians, native Americans and AlaskansTreatment considerations

Dens evaginatus Dens invaginatusDens in denteDeep surface invagination of crown that is lined by enamelRepresents an accentuation of the lingual pitDepth variesPrevalence studies vary from <1% to 10%Lateral incisors most commonly affectedBilateral involvement commonTreatment considerations

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Dens invaginatus TaurodontismEnlargement of the body and pulp chamber of a multirooted tooth with apical displacement of the pulpal floorMore commonly seen in permanent dentitionPrevalence is highly variable

2%-3% in U.S.Much higher in Eskimos and Middle Eastern populations

Increased frequency in patients with CL and/or CP, Down, Klinefelter,ectodermaldysplasia, trich-dento-osseous

Taurodontism DilacerationAbnormal angulation or bend in the rootThought to be related to trauma during root developmentPermanent maxillary incisors most commonly affected followed by mandibular incisorsRare in primary dentitionTreatment depends on severity

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Dilaceration Amelogenesis imperfectaA heterogeneous group of hereditary disorders that demonstrate developmental alterations in the structure of enamel in the absence of a systemic disorderMany subtypesNumerous patterns of inheritanceWide variety of clinical manifestationsFrequency varies between 1:718 and 1:14,000Both dentitions involved

Amelogenesis imperfectaFormation of enamel a multistep process

Formation of enamel matrixMineralization of matrixMaturation of matrix

Hereditary defects of enamel formation usually classified as:

HypoplasticHypocalcifiedHypomaturative

Amelogenesis imperfectaWitkop classification

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Amelogenesis imperfectaHypoplastic

Teeth erupt with insufficient amounts of enamelAmount of enamel varies greatlyEnamel present is mineralized appropriately and contrasts well with dentin on radiographs Teeth may have abnormal shape and open contactsOpen bite may be present

AI-Hypoplastic smooth

AI-Hypoplastic pitted AI-Hypoplastic pitted

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AI-Hypoplastic rough Amelogenesis imperfectaHypocalcified

Proper amount of enamel matrix is formed but but it doesn’t mineralize properlyTeeth shaped normally upon eruption but enamel is soft and easily lostEnamel yellow-brown upon eruption but quickly becomes brown to blackAccumulate calculusEnamel and dentin have similar density on radiographs

AI-Hypocalcified AI-Hypocalcified

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Amelogenesis imperfectaHypomaturative

Enamel matrix is laid down properly and begins to mineralize but there is a defect in maturation of enamel’s crystal structureAffected teeth normal in shapeMottled appearance-white, brown or yellowEnamel soft and chips away from dentinEnamel has similar radiodensity to dentin

AI-Hypomaturative

AI-Hypomaturative, snowcapped Dentinogenesis imperfecta

Hereditary developmental disturbance of dentinAutosomal dominantAlso known as hereditary opalescent dentinShields classificationPrevalence is about 1:8000

Most cases in whites of English or French ancestry from communities near English Channel

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Dentinogenesis imperfectaAll teeth in both dentitions affectedDeciduous teeth affected most severely followed by permanent incisors and first molarsYellow-brown to blue-gray translucent, opalescent appearanceEnamel frequently separates easily from dentinOnce exposed, dentin exhibits rapid attritionBulbous crowns with cervical constrictionThin rootsEarly obliteration of pulp chambers and root canals

Dentinogenesis imperfecta

Dentinogenesis imperfecta Dentinogenesis imperfecta

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Dentinogenesis imperfecta Dentinogenesis imperfecta

Dentin dysplasiaRare autosomal-dominant condition that affects dentinPrevalence about 1:100,000

Dentin dysplasiaType I

Radicular type or ‘rootless teeth’Roots short and pulps almost obliteratedPeriapical radiolucenciesMore common typeEnamel and coronal dentin are normalWide variation in root formation because dentinal disorganization may occur at different stages of tooth developmentColor is normal in both dentitionsRadiographically, deciduous teeth more severlyaffected

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Dentin dysplasia type I Dentin dysplasia type I

Dentin dysplasia Dentin dysplasia

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Dentin dysplasiaType II

Coronal typeRoot length normal in both dentitionsPrimary teeth

Clinically resemble dentinogenesis imperfectaRadiographically have similar appearance to Type I

Permanent teethNormal colorationPulp chambers enlarged with apical extension-thistle-tube-shaped or flame-shaped

Dentin dyplasia type II

Dentin dyplasia type II Regional odontodysplasia‘Ghost teeth’Localized, non-hereditary developmental abnormality of teeth with extensive adverse effects on formation of enamel, dentin and pulpOccurs in region or quadrantEtiology unknownOccurs in both dentitions and if present in primary dentition,permanent teeth in area usually affectedMaxillary predominance- 2.5:1Many affected teeth fail to eruptErupted teeth have small irregular yellow-brown crownsShort roots, enlarged pulp and open apical foramina

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Regional odontodysplasia Regional odontodysplasia

Regional odontodysplasia ReferencesOral & Maxillofacial Pathology-Second Edition

Neville, Damm, Allen and BouquotOral Pathology-Clinical Pathologic Correlations

Regezi, Sciubba and Jordan

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Thank you!