Disorders of development of teeth and craniofacial anomalies. Markéta Hermanová •Disturbances in number of teeth •Disturbances in size of teeth •Disturbances in form of teeth •Disturbances in structure of teeth •Craniofacial anomalies Disorders of development of teeth. Disorders of development of teeth. nPrenatal nPostnatal n nInherited nAquired Disturbances in number of teeth. nHypodontia, anodontia, and associated syndromes n nHypohidrotic ectodermal dysplasia n nHyperdontia (supernumerary teeth) nHypodontia: congenital absence of teeth -More common in the permanent dentition (2-10 % in populations) -In primary dentition <1 %; assoc. with the absence of permanent succesional tooth -Racial and geographic differences -Symetric/asymetric -3rd molar, permanent maxillary lateral incisors, mandibullary 2nd premolars -A role of control and regulating genes in the development of teeth -Assoc. wih other craniofacial anomalies and syndromes - nAnodontia: complete absence one or both dentitions nHypohidrotic ectodermal dysplasia -Congenital absence of ectodermal structures - -X-linked (GR), mutation in EDA gene (signalling molecule), failure of interactions between epithelial and mesenchymal tissues; rarely AR - -Smooth dry skin, scanty hairs, partial or total absence of sweat glands (hyperthermia) - -Severe hypodoncia (teeth retarded in eruption, deformed teeth, conical crowns of teeth) - -Female carriers - minimal hypodontia nHyperdontia (supernumerary teeth) -maxilla (anterior and molar regions) -assoc. with cleft palate and cleidocranial dysplasia -F>M -Unusual in deciduous dentition -Prevent the eruption, causes malposition, resorption of adjacent teeth, developlment of dentigerous cysts if unerupted -Mesiodens: between maxillary central incisors -Paramolar: alongside the maxillary molars, usually buccaly placed -Distomolar: distally to a 3rd molar Syndrom/anomaly Associated features Hypodontia Cleft lip/palate Deafness, cranial and skeletal abnormalities Crouzon syndrome (FGFR gene, AD) Craniosynostosis, maxillary hypoplasia, hypertelorism Down syndrome (trisomy 21) Multiple, e.g. mental retardation, macroglossy, maxillary hypoplasia, anomalies of heart Hypohidrotic ectoderma dysplasia Hypotrichosis, hypohidrosis, saddle-nose Ellis-van Creveld syndrome Dwarfism, polydactyly, cardiac malformations Oro-facial digital syndrome Cleft palate, hypoplasia of nose, digital malformations Hyperdoncie Cleft lip/palate Deafness, cranial and skeletal abnormalities Cleidocranial dysplasia (RUNX2 gene, AD) Aplasia of clavicles, delayed ossification of fontanelles, enlargement of cranium Gardner syndrome (APC gene, AD) Osteomas of jaws, skin cysts and fibromas, intestinal polyposis-carcinomas Sturge-Weber angiomatosis Venous angiomatosis (also facial and oral), cerebral angiomatosis Oro-facial digital syndrome Cleft palate, hypoplasia of nose, digital malformations Gardner syndrome Cleidocranial dysplasia. Hypodontia. Orofacial clefts nIn combination with over 300 syndromes n n70 % non-syndromic n n1/500-1000 births n nClefts of the lip and palate (45 %)>clefts of the palate (30 %) >clefts of the lip (25 %) n nMultifactorial causes n n nCleft lip: defective fusion of the medial nasal process with maxillary proces n nCleft palate: failure of palatal shelves to fuse Cleft of the lip: -Unilateral -Bilateral Cleft of the palate Cleft of the lip and palate -Unilateral -Bilateral nLateral facial cleft (isolated or with mandibulafocial dysostosis): lack of fusion of the maxillary and mandibullary processes; uni- or bilateral n nOblique facial cleft n (from upper lip to the eye, +CP; failure of fusion of the lateral masal process with the maxillary process or caused by amniotic bands) n nMedian cleft of the upper lip n (failure of fusion of the medial nasal processes; in several syndromes, in holoprosencephaly) n nMedian maxillary anterior alveolar clefts n (bony defect in the midline of the maxilla between incisors) n n Disturbances in size of teeth nMacrodontia nMicrodontia n -Genetic factors n(microdontia in Down syndrome, in congenital heart diseases) -Environmental factors -May involve the entire dentition n n Disturbances in form of teeth. nDilaceration -Tooth severely bent along its long axis, trauma -Maxillary incisor n nTaurodontism -Pulp chamber higher, with no constriction in amelocemental junction -Failure of Hertwig´s sheath invaginate at the proper horizontal level -Sporadic or assoc. with Klinefelter and poly-X chromosomes syndromes n nDouble teeth -Developmental anomaly, teeth joined together (crowns, roots, or both (with/without joining of the pulp) -More often in primary dentition -Fusion (the union of two or more separate developin) -Gemination (incomplete division of teeth) n nConcrescence -Acquired disorder, affects more often permanent dentition -Teeth united by cementum (anatomically close teeth (2nd and 3rd maxillary molar, hypercementosis in inflammation) n Taurodontism Dilaceration Fusion Gemination Disturbances in structure of teeth nDisturbances in structure of enamel n nDisturbances in structure of dentine n nDisturbances in structure of cementum Amelogenesis Secretory phase Secretions of enamel matrix proteins by ameloblasts: amelogenin, enamelin, ameloblastin, tuftelin Enamel matrix proteins – maturation iniciation Crystallites growing mainly in length, little in width or thickness Amount of matrix produced determines thickness of enamel and crown morphology Maturation phase Secretion of matrix protein ceases Growth in length of crystallities is terminated Secretion of proteolytic enzymes and degradation of matrix proteins Crystallites growing in width and thickness nDefective matrix production – enamel hypoplasia n n nDefective maturation/mineralisation n – hypomineralized enamel Local causes of developmental abnormalities of enamel Infection, trauma, radiotherapy. Idiopathic. General causes Environmental/systemic causes (chronological dysplasias) Prenatal Infections: rubeolla, syphilis,… Maternal diseases Excess fluoride ions Neonatal Hemolytic disease of newborn Hypocalcaemia Premature birth/prolonged labour. Postnatal Infections (viral exanthemata) Heart diseases, endocrinopathies, GIT diseases Avitaminosis (D) Chemotherapy Excess fluoride ions Genetic causes Teeth affected Amelogenesis imperfecta + generalized defects Ectodermal dysplasia syndromes , Down syndrome Genes encoding enamel proteins. nAmelogenin nEnamelin nAmeloblastin nTuftelin n Amelogenesis imperfecta. n2 types: -hypomineralized/hypomaturation type n(normal tooth morphology when first erupt, soft chalky enamel easily lost, exposing dentine) -hypoplastic type n(enamel of normal hardness, variable thickness) n nAD most often; rare XR (amelogenin) n Local causes of developmental abnormalities of dentine Trauma, radiotherapy, Turner teeth (due to trauma/infection of primary teeth) General causes of developmental abnormalities of dentine Dentinogenesis imperfecta Typ I Typ II Typ III assoc. with osteogenesis imperfecta Teeth only affected, AD, both dentitions affected, discoloration (amber like), obliteration of pulp Racial isolate in USA, type II like Dentinal dysplasia Typ I Typ II Radicular (rootless teet) Coronal Environmental/systemic causes Avitaminosis D Hypophosphatemia Hypophosphathasia Juvenile hypoparathyreoidism Other mineral deficiences, drugs, chemotherapeutics,… Turner tooth nenamel hypoplasia involving a solitary permanent tooth; related to infection in the primary tooth that preceded it or to trauma during odontogenesis. n nenamel discoloration, abnormal coalescence or enamel missing; in severe cases dentine and cementum also affected Regional odontodysplasia („ghost teeth“) -Unknown etiology -Abnormalities of enamel, dentin, pulp, dental follicle -Both dentition affected -Delayed eruption of abnormally formed tooth -Reduced radioopacity of the teeth with lost of distinction between enamel and dentine („ghostly“ appearance) Regional odontodysplasia („ghost teeth“) Hypoplastic enamel with globular calcifications, mostly atubular dentine, with clefts. Dentine, mostly atubular, with fields of amorphous dentine with globular formations. Regional odontodysplasia („ghost teeth“) Follicular tissues of unerupted tooth with remnants of odontogenic epithelium, fibrous tissues and calcifications of soft tissues. Follicular tissues of unerupted tooth with remnants of odontogenic epithelium (immunohistochemically with positive expression of cytokeratins – epithelial tissues markers). Disturbance in structure of cementum. nCoronal third covered by a narrow layer of acellular (primary) cementum napical 2/3 covered by an additional thicker layer of cellular (secundary) cementum n nHypercementosis -Idiopathic or known causes -Ancylosis, concrescence -causes: periapical inflammation, mechanic stimulation, functionless/unerupted tooth, Paget´s disease of bone n nHypocementosis -In hypophosphatasia, in cleidocranial dysplasia,….. n n Causes of macroglossia Congenital and hereditary Vascular malformations Hemihyperplasia Cretenism Beckwith-Wiedemann syndrome (omphalocele, visceromegaly, gigantism, hypoglycemia) Down syndrome Mucopolysaccharidoses Neurofibromatosis Multiple endocrine neoplasia, type 2B Acquired Edentulous patients Amyloidosis Myxedema Acromegaly Angioedema Tumors nMicroglossia nAglossia n(in oromandibular-limb hypogenesis syndrome) n nAncyloglossia (tongue-tie) n(short, thick lingual frenum) •Oral pathology textbook not neccesary •Material from lectures obligatory! Thanks for your attention……..