Developmental disorders Assoc. Professor Jan Laco, MD, PhD

Developmental disorders 1. Teeth 2. Jaws 3. Clefts 4. Oral soft tissue

Developmental disorders - teeth 1a. Abnormalities of size and form 1b. Abnormalities of number 1c. Defects of structure 1d. Disorders of eruption

1a. Abnormalities of size and form microdontia …teeth < normal permanent teeth absolute x relative generalized x single (upper I2, M3) macrodontia …teeth > normal generalized x single

1a. Abnormalities of size and form gemination (schizodontia, twinning) incomplete division of tooth germ 2 separated crowns on single root, upper I1 fusion (synodontia) concrescence fusion after development of roots (injury) teeth united by cementum

1a. Abnormalities of size and form dilaceration angulation at crown-root junction (injury) difficult extraction talon cusp lingual or palatal aspect of permanent teeth dens invaginatus (dens in dente) invagination of enamel into pulp chamber upper I2, bilateral, caries

1a. Abnormalities of size and form taurodontism (bull tooth) wide pulp chamber molars enamel pearl displaced ameloblasts below amelocemental junction mm nodule, upper M

Developmental disorders - teeth 1a. Abnormalities of size and form 1b. Abnormalities of number 1c. Defects of structure 1d. Disorders of eruption

1b. Abnormalities of number Isolated hypodontia – common hereditary M3 + P2 + I2 M3 + P2: NO effect I2: false eruption of C to I1 Anodontia – very rare

1b. Abnormalities of number Anhidrotic ectodermal dysplasia X-linked inheritance hypodontia + hypotrichosis + anhidrosis failure of development of alveolar process Down´ s syndrome no M3 (90% patients)

1b. Abnormalities of number Hyperdontia (additional teeth) – common supernumerary: conical incisor + molar region + midline (mesiodens) supplemental: normal excessive growth of l. dentalis M4 Cleidocranial dysplasia Gardner´s syndrome

Developmental disorders - teeth 1a. Abnormalities of size and form 1b. Abnormalities of number 1c. Defects of structure 1d. Disorders of eruption

1c. Defects of structure deciduous teeth neonatal jaudice  yellow congenital porphyria  red Tetracycline permanent teeth periapical infection of d. predeccesor – Turner tooth systemic diseases

1c. Defects of structure – systemic diseases genetic amelogenesis imperfecta dentinogenesis imperfecta Ehlers-Danlos syndrome, Gardner´s syndrome infective – congenital syphilis metabolic – childhood infections, rickets drugs – tetracycline, cytotoxic chemotherapy fluorosis

1c. Defects of structure – systemic diseases Amelogenesis imperfecta all teeth + whole enamel x dentine normal Hereditary enamel hypoplasia AD inheritance defect of matrix formation – pits, grooves, hard Hereditary enamel hypocalcification AD + AR inheritance normal matrix poorly calcified – soft, chalky

1c. Defects of structure – systemic diseases Chronological hypoplasia transient impairment of enamel formation in case of severe illness severe fever, gastroenteritis, measles in the past horizontál bands of pits, grooves, defects Molar-incisor hypomineralisation all M1 a I1 a I2 enamel - hard surface, but soft beneath yellow brown discoloration, ↑ caries

1c. Defects of structure – systemic diseases Dentinogenesis imperfecta defect of collagen/sialoprotein, AD normal teeth shape brownish, translucent enamel  chip away obliteration of pulp dentine - few tubules + abnormal matrix + incomplete calcification “shell teeth“ – thin mantle of dentine covers abnormal dentine, few odontoblasts, no roots Dentinal dysplasia very short and conical roots, teeth are lost early Regional odontodysplasia (ghost teeth (radiolucent on RTG)) hypoplastic / hypomineralised enamel + thin dentine

1c. Defects of structure – systemic diseases Ehlers - Danlos syndrome (floppy joints) collagen disorder hypermobile joints + loose skin small teeth + short roots + pulp stones Gardner´s syndrome multiple osteomas (jaws) + skin tumors + colonic polyps  malignant change impacted teeth, supernumerary teeth

1c. Defects of structure – systemic diseases Congenital syphilis – Hutchinson (1858) later fetal infection dental follicle infection by T. pallidum chronic inflammation  fibrosis of tooth sac  compression of developing tooth  distortion of ameloblasts permanent teeth upper I1 (Hutchinson´s incisors) – barrel-shaped, fissure on incisal edge M1 (Moon´s molars) – dome-shaped, pitted occlusal surface (“mulbery molar“)

1c. Defects of structure – systemic diseases Tetracycline (TTC) taken up calcifying tissues yellow fluorescence (UV light) during teeth development – fetus x infancy dentine bright yellow  brown  grey permanent teeth Avoid TTC under 12 years

1c. Defects of structure – systemic diseases Fluorosis (mottled enamel)  fluoride in drinking water, India during dental development paper-white patches  brown permanent teeth hydroxyapatite  calcium fluoroapatite patches of incomplete calcification with high organic and water content enamel matrix usualy normal

Developmental disorders - teeth 1a. Abnormalities of size and form 1b. Abnormalities of number 1c. Defects of structure 1d. Disorders of eruption

1d. Disorders of eruption deciduous teeth: 6th – 30th month at birth: natal teeth 1st month: neonatal teeth (lower I1) permanent teeth: 6th – 13th y (M3: 18th – 30th y) loss of space, retention of a dec. predecessor cretenism, rickets

Developmental disorders 1. Teeth 2. Jaws 3. Clefts 4. Oral soft tissue

2. Developmental disorders - jaws micrognathia x macrognathia hereditary prognathism craniofacial anomalies cherubism Gardner´s syndrome osteogenesis imperfecta

Developmental disorders 1. Teeth 2. Jaws 3. Clefts 4. Oral soft tissue

3. Developmental disorders - clefts NOT clefts  non-fusion !!! ? ethiology - genetic component (40%) cleft lip -  males, inc. 1/1000 cleft palate -  females, inc. 1/2000 lip : lip + palate : palate …22% : 58% : 20% + Down´s syndrome (1 in 200 pts.) van der Woude syndrome (AD, IRF6 gene) clefts + pits on lower lips + hypodontia

3. Developmental disorders - clefts cleft lip – cheiloschisis lateral: unilateral (left side) x bilateral medial alveolar ridge cleft – gnathoschisis hard palate cleft – palatoschisis soft palate cleft - uranoschisis uvula cleft - staphyloschisis

3. Developmental disorders - clefts complications malformation or absence of teeth in defect + other congenital defects feeding disorder breathing disorder middle ear infections speech defect cosmetic defect

Developmental disorders 1. Teeth 2. Jaws 3. Clefts 4. Oral soft tissue

4. Developmental disorders – oral soft tissues 4a. oral mucosa 4b. gingiva and periodontium 4c. tongue

4a. Developmental disorders – oral mucosa white sponge nevus – AD inheritance white, soft, thickened area of oral mucosa Mi: acantosis + hyperkeratosis + intracellular edema Fordyce´s granules heterotopic sebaceous glands 80% adults soft yellowish spots or papules symmetrical, buccal location

4b. Developmental disorders – gingiva and periodontium hereditary gingival fibromatosis AD inheritance grossly enlarged gingivae - preceding of teeth eruption Mi: collagen bundles gingivectomy after puberty Ehlers-Danlos syndrome

4c. Developmental disorders – tongue macroglossia muscle hypertrophy congenital hemangioma or lymphangioma Down´s syndrome lingual thyroid incidence 10% nodule, foramen caecum cleft tongue ankyloglossia

4c. Tongue Lingua plicata cerebelli-, cerebriformis, fissurata, gyrata, scrotalis fissured dorsal aspect of tongue children x adults asymptomatic x pain during eating, hygiene + geographical tongue + Cowden syndrome + Melkersson-Rosenthal syndrome

4c. Jazyk Lingua geographica geographical tongue, glossitis migrans + lingua plicata; ± psoriasis asymptomatic x pain during eating irregular smooth red area  healing (hours / days)  another red area appears centre – epithelium thinning; periphery – hyperplasia + keratinization; mild inflammation