Pediatric dentistry II Tooth development Defects of teeth Tooth development, eruption and shedding Defects of tooth development 1. Enamel defects 2. Dentin defects 3. Defects - both enamel and dentin 4. Cement defects 5. Defects - both dentin and cement 6. Defects of tooth form, size, and number Defects of enamel formation A. Environmental determinants 1. Developmental 2. Traumatic 3. Inflammatory and infectious 4. Chemical and metabolic B. Hereditary determinants 1. Primary defects in enamel in amelogenesis 2. Defect in enamel accompanied by generalized condition 3 basic manifestations 1. Hypoplasia – reduction of enamel thickness (whole, partly) 2. Hypocalcification – lack of initial calcification of enamel, or unsatisfactory calcification 3. Hypomaturation – lack of secondary mineralization or maturation A- Environmental defects of enamel 1. Developmental defects natal, neonatal lines. Extent – microscopic - hypoplasia. Only in primary dentition (development of permanent starts later ) Cause – pretermed birth, immaturity, Diabetes mellitus in mother, heart diseases, and other systemic diseases 2. Traumatic defects of enamel A. physiologic attrition – consequence of natural tooth contacts B. pathologic attrition – intensification - bruxism, use of teeth as tools Exposure of the dental pulp – rarely (secondary dentin formation) C. abrasion – pathologic loss of enamel ( and dentin) as the consequence of physical forcel other than that of occlusion (mastication). Wedge defects,plaing woodwings instruments, tooth brushing, pipe smoking D. mutilation – ritual abrasion (Afrika, Eskimosi) E. ionizing radiation F. physical trauma – fractures, surgical repair of clefts etc. A – Environmental defects 3. Inflammatory and infectious A. Turner tooth – damage of permanent bud by chronic inflammation in primary tooth periodontium!!! B. Enamel hypoplasia as a result of fever, direct effecton odontogenic epithelim – rubeola virus C. congenital syphilis – Hutchinson´s teeth, mulberry molars A - Environmental defects 4. Chemical and metabolic influences A. fluorosis B. tetracyclines C. chemical colourings –metallic, non-metallic, copper, lead, iodides, bromides D. Defects of metabolism • alkaptonuria– brownish discoloration of permanent teeth • Congenital erythropoetic porphyria – primary teeth – yellow, brown, pink to red – enamel and dentin permanent teeth – dentin and cement • erythroblastosis fetalis and icterus gravis neonatorum – yellow to green – primary dentition incorporation of bilirubini nto enamel. hypoplasia • Other hemolytic diseases – also in permanent dentition, if the disease appeared in early childhood E. erosion – dissolution od enamel by chemical process • idiopatic erosion – composition of saliva (citric acid) • dietetic erosion – citrus fruits, coca – cola Hereditary determinants A. PRIMARY DEFECT OF ENAMEL DURING AMELOGENESIS (AMELOGENESIS IMPERFECTA) 1. Hypoplastic type a) pitted AD b) local AD c) smooth AD d) smooth XD, bound to x e) rough AD f) hypoplastic – hypomaturation AD g) rough AD 2. Hypocalcified type a) autosomal dominant b) autosomal recessive 3. Hypomaturation type a) bound to x – chromosome XR b) pigmented AR c) snow capped teeth AD d) enamel opacities white hypomaturated enamel AR Prevalence 1 : 14 000 –most common – AD hypocalcified A. PRIMARY DEFECT OF ENAMEL DURING AMELOGENESIS (AMELOGENESIS IMPERFECTA) HYPOPLASTIC FORM –local defects and generalized forms – most common AD In men – form bound to x – chromosome Thin enamel, no contacts between teeth, both dentitions affected HYPOMATURATION FORM – soft enamel, detaching from dentine X bound recessive - the most frequent Defect is in enamel rods (sheath) Rods are missing – pigmented debris – both dentitions affected HYPOCALCIFIED FORM – AD Enamel detaching from dentine - sensitive Open bite – frequently Defect in intraprismatic calcification B. INHERITED DEFECTS OF ENAMEL IN GENERALIZED DISEASES In 33 kinds of generalized conditions –all types of Amelogenesis imperfecta as a part of syndroms The most importants: epidermolysis bullosa, mucopolysacharidosis, rachitis, ectodermal dysplasia, Down syndrome, dysostosis mandibulofacialis, dysostosis cleidocranialis, fenylketonuria, neurofibromatosis, sclerosis tuberosa DEFECTS OF DENTINE A. Environmental determinants 1. Inflammatory and infectious 2. Developmental 3. Chemical and metabolic B. Hereditary determinants 1. Primary defects in dentine in dentinogenesis 2. Defects in dentine accompanied by generalized condition A. Environmental determinants 1. Developmental Neonatal, infantile, pubertal lines – hypomineralized bands – trauma „in utero „ , during childbirth, hormons influence No clinical significance 2. Inflammatory and infectious determinants – External and internal resorption – Tertiary dentine formation – Pulp stones and calcification 3. Chemical and metabolic determinants a) deficiency of C vitamine– irregular course of tubules, scurvy – cessation of tooth development b) deficiency of D vitamine – predentine enlargment c) hypervitaminosis D – calcification in the dental pulp, hypermineralization of enamel and dentine matrix d) tetracyclines – binde to organic and inorganic component – chromogenic dentine e) hypoparathyreosis – calciotraumatic complex, hypomineralization B. Hereditary determinants 1. Primary defect in dentin during dentinogenesis – Dentinogenesis imperfecta (opalescent dentine) Brown translucent teeth, both dentitions Dental pulp: cavity – obliteration – AD Rapid abrasion, atubular dentine, changes in connective tissue of the dental pulp – Dentinal dysplasia Radicular dysplasia – AD Rootless teeth, both dentitions Dental pulp obliteration – Coronal dysplasia – AD, rare – Progressive dental pulp obliteration 2. Defect of dentine accompanied by generalized conditions – Dentinogenesis imperfecta + osteogenesis imperfecta generalized disease of connective tissue Fragile bones, blue sclerae, defects of dentine, vestibulocochlear deafness brown –bluish teeth, dental pulp obliteration RAPID ABRASION – Fibrous dentinal dysplasia – AD – Unger – Trott´s syndrome – AD or. X chrom. Branchioskeletogenital syndrome – Vitamin D resistent rachitis (rickets) Hypophosphatasia X bound De Toni – Debré – Fanconi syndrome A. R DEFECTS – ENAMEL AND DENTINE A. ENVIRONMENTAL DETERMINANTS 1. developmental 2. traumatic as well as in defects of enamel, dentine 3. inflammatory, infectious 4. chemical, metabolic hypoplasia of enamel – detachment from dentine discoloration by biliary dyes (hepatitis, obstruction) B. HEREDITARY DETERMINANTS 1. primary defect of enamel, dentine in odontogenesis Odontodysplasia – both dentitions, probably somatic mutation affects part of the dental lamina Enamel – hypoplasia, hypocalcification, rods are missing Dentine – thin, abnormal tubules Dental pulp – fibrous, pulp stones, calcificatios 2. defect of enamel, dentine accompanied by generalized conditions Pseudohypoparathyreosis X, AD Hypocalcemia – does not respond to parathormon treatment Enamel –pits, hypoplasia Dentine – different calcification, open, short apexes Into this group – many hereditary diseases DEFECTS OF CEMENTOGENESIS A. Environmental defects 1. developmental 2. traumatic 3. inflammatory, infectious 4. chemical, metabolic B. HEREDITARY A. ENVIRONMENTAL 1. developmental – (dentes concreti, confusi) – true (confusi) – false (concreti) 2. traumatic hypercementosis 3. inflammatory 4. chemical, metabolic Scurvy – defect in collagen fibres formation - periodontal ligament is detaching from the surface of cement B. HEREDITARY A. HEREDITARY FACTORS 1. primary defect of cement in cementogenesis Hereditary multiple cementosis AD 2. Defects accompanied by general conditions A. dysostosis cleidocranialis AD defects of structure and eruption B. osteitis deformans (Paget) AD DEFECTS AFFECTING CEMENT AND DENTINE Hypophosphatasia Primary – the bone system AR Premature loss of primary teeth, low level of AF Reduction of cement and dentine thickness, large dental pulp cavity GEMINATION TWINNING FUSION CONCRESCENCE Different types of fusion with gemination (double teeth)