Dental Anomalies in Radiology wcwangkmu edu tw Wen

Dental Anomalies in Radiology 王文岑 助理教授 口腔病理影像診斷科 wcwang@kmu. edu. tw Wen. Chen Wang

2 學習目標 | | 判讀X光片上的牙齒異常 Developmental abnormalities v. s. acquired 資料來源 u u u Ref 1: White SC, Pharoah MJ. Oral Radiology: Principles and interpretation 6 th ed. 2009. Ref 2: Neville BW, Damm DD, Allen CM and Bouquot JE. Oral & maxillofacial patholgy 3 nd ed. 2009. Ref 3: 高醫口腔病理診斷門診病例 Wen. Chen Wang

3 Developmental Abnormalities Supernumerary Teeth (hyperdontia, supplemental teeth) | 1~4% , familial tendency n n n Mesiodens, paramolar Distodens, distomolar teeth Peridens Single : premaxilla, maxillary molar Multiple : premolar area, mandibular M: F = 2: 1 | Impaction or delay eruption of normal teeth; dentigerous cyst Syndrome: | Cleidocranial dysplasia, Gardner’s syn. | Ref. 1 Wen. Chen Wang

4 Ref. 3 Wen. Chen Wang

Cleidocranial dysplasia Ref. 3 Wen. Chen Wang

Cleidocranial dysplasia Ref. 3 Wen. Chen Wang

Cleidocranial dysplasia Ref. 3 Wen. Chen Wang

8 Cleidocranial dysplasia Ref. 3 Wen. Chen Wang

Cleidocranial dysplasia Ref. 3 Wen. Chen Wang

10 Missing Teeth | 3~10%, excluding 3 rd molars Hypodontia Oligodontia Anodontia | 8>5>2>1 | | 1. Ectodermal dysplasia; 2. orofaciodigital syndrome Ref. 1 Wen. Chen Wang

11 Submergence Infraocclusion, Secondary retention, Reimpaction, Reinclusion | | | most affect 8~9 y/o children and teeth D&E PDL absent , ankylosis Occlusal and periodontal problems Ref. 3 Wen. Chen Wang

12 ectodermal dysplasia Ref. 1 Wen. Chen Wang

Ectodermal dysplasia Ref. 3 Wen. Chen Wang

14 SIZE OF TEETH | True generalized type and relative type Macrodontia | Hemangioma, hemihypertrophy of the face, pituitary giantism Microdontia | pituitary dwarfism rd molars, | supernumerary teeth, 3 lateral incisors Wen. Chen Wang

15 Macrodontia Microdontia Ref. 1 Wen. Chen Wang

16 ERUPTION OF TEETH Transposition Two teeth exchanged positions | 3 & 4 ; 3 & 2, 657 | Ref. 1 Wen. Chen Wang

17 Transposition Ref. 3 Wen. Chen Wang

18 Altered Morphology of Teeth Gemination (twinning) -Division of a single tooth bud | primary dentition , esp. incisor region | complete twinning increase tooth number | pulp chamber is single & enlarged, maybe partial divided Ref. 3 Ref. 1 Wen. Chen Wang

19 Fusion (synodontia) -Adjacent tooth germs combined with dentin or enamel | | bifid crown or two recognizable teeth, reduced number of teeth more common in the primary dentition, esp. anterior region Ref. 1, 2 Wen. Chen Wang

20 Concresence - Roots of two or more teeth united by cementum | | Fusion after root formation Traumatic injury or crowding Pre-extraction x-ray check maxillary molars; 3 rd molar & a supernumerary tooth Ref. 1 Wen. Chen Wang

21 Taurodontism -Longitudinal enlarged pulp chamber, increased distance between CEJ to the bifurcation | | normal crown size & tooth length, shortened roots not recognizable clinically most in molars Trisomy 21 Ref. 1 Wen. Chen Wang

22 Dilaceration - | A sharp bend or curve in the crown or root maxillary premolars Ref. 1 Wen. Chen Wang

23 Dens in Dente (dens invaginatus) - Infolding of the outer enamel surface into the interior | at the anatomically defined pit | caries→pulpal disease coronal type: enamel organ infolding into the dental papilla; 2>1>4, 5>3 radicular type: invagination of Hertwig’s epithelial root sheath, lined with cementum; | 4, 7 Ref. 1 Wen. Chen Wang

24 Dens in Dente radicular type Ref. 1 coronal type Dilated odontome Wen. Chen Wang

25 Dens Evaginatus - Outfolding of enamel organ | a tubercle on occlusal surface, with enamel surface & dentin core, pulp horn often extends into the evagination | premolar or molar | pulp infection due to fracture Ref. 1 Ref. 2 Wen. Chen Wang

26 Amelogenesis Imperfecta -Disturbance in enamel development | Normal dentin & root | autosomal dominant or recessive , X-linked 1. Hypoplastic type | | | Thin enamel with pitted, rough or smooth & glossy surface; yellowish to brown undersized, squared crown, lack of contact flat occlusal surface & low cusps, attrition 2. Hypomaturation n normal thickness of enamel, but mottled surface; cloudy white, yellow or brown, opaque in color softer than normal same density as dentin 3. Hypocalcified type n normal thickness of enamel, density less than dentin normal size & shape when erupt, abrade or fracture away rapidly permeability increase, darkened & stained 4. Hypomaturation-hypocalcified with taurodontism Wen. Chen Wang

27 Amelogenesis Imperfecta Hypoplastic type Hypocalcified type Ref. 1 Wen. Chen Wang

28 Dentinogenesis Imperfecta (hereditary opalescent dentin) | Autosomal dominant hereditary Type I : DI + OI (osteogenesis imperfecta) COL 1 A 1, COL 1 A 2 Type II : Isolated DI. (1/8000) DSPP Type III: DI of the Brandywine type * DSPP n A racial isolate in Maryland, DI + multiple pulp exposures in deciduous teeth | enamel fractures, attrition severely | dark brown to black Radiographic Features of D. I. : | bulbous crown, normal size, constriction of the cervical area | short & slender roots, occlusal attrition | partial or complete obliteration of the pulp chambers, root canals absent or threadlike n Wen. Chen Wang

29 Dentinogenesis Imperfecta Ref. 1 Wen. Chen Wang

30 Dentin Dysplasia -autosomal dominant disturbance | rare (1: 100, 000) Type I (radicular) normal color & shaped in both dentition u malaligned arch, drifting and exfoliate with little or no trauma short or abnormal root shaped, pulp chamber & root canals completely filled in before eruption 20 % of teeth with type I disease have apical radiolucencies u | | Ref. 1 Wen. Chen Wang

31 Dentin Dysplasia Type. II (coronal) | | | Ref. 1 primary dentition appears as D. I. , but permanent dentition is normal obliterated of the pulp chamber & reduced root canals after eruption roots are normal in shape & proportion Wen. Chen Wang

32 Regional Odontodysplasia (odontogenesis imperfecta) - hypoplastic & hypocalcified of both dentin & | | | enamel only a few adjacent teeth in a quadrant affected either primary or permanent teeth central incisors > lateral incisors >canines (maxillary) delayed eruption ghostlike appearance in image large pulp chamber & wide root canals, roots are short & poorly outlined thin enamel , less dense as usual Wen. Chen Wang

33 Regional Odontodysplasia Ref. 1 Wen. Chen Wang

34 Enamel Pearl (enameloma, enamel drop, enamel nodule) - small globule of enamel on the roots furcation area of molars | prevalence : 3 % | mesial or distal aspect in Max. molar and buccal or lingual in Mand. molars Ref. 1 Wen. Chen Wang

35 Talon Cusp - Anomalous hyperplasia of the cingulum of a Max. or Mand. incisor →a supernumerary cusp | T shaped in incisal view | Differential diagnosed with supernumerary tooth Ref. 1 Ref. 2 Wen. Chen Wang

36 Turner’s Hypoplasia (Turner’s tooth) -a type of enamel hypoplasia - local hypoplastic or hypomineralized defect in crown of a permanent tooth | extension of a periapical infection or mechanical trauma from deciduous predecessor | most common in lower premolars Ref. 2, 3 Wen. Chen Wang

37 Turner’s tooth (enamel hypoplasia) Ref. 1 Ref. 3 Wen. Chen Wang

38 Congenital Syphilis | | | 30 % p’t develop dental hypoplasia Hutchinson’s incisors & mulberry molars not all p’t with Hutchinson’s teeth or mulberry molars will have congenital syphilis Hutchinson’s incisors (screw driver shape) Ref. 1 Wen. Chen Wang

39 Acquired Pathologic Conditions Attrition -Physiologic wearing from | | occlusal contacts Incisal, occlusal and interproximal surfaces(contact points) Depends on the abrasiveness of diet, salivary factors, mineralization, emotional tension Bruxism--pathologic condition Crown shorten, reduction of pulp chamber & canals Abrasion -Nonphysiologic wearing by contact with foreign substances | Factitious habits or occupational hazards | tooth brushing, flossing, pipe smoking, opening hairpins with teeth Wen. Chen Wang

40 Tooth Brushing Injury | | V-shaped groove in cervical area Sensitive Maxillary premolars >canines > incisors R-L defect at cervical level, well-defined semilunar shapes Ref. 1 Ref. 3 Wen. Chen Wang

41 Dental Floss Injury | | Cervical portion of proximal surfaces just above gingiva Narrow semilunar RL, distal surface often deeper than mesial Ref. 1 Wen. Chen Wang

42 Erosion -Chemical action not involving | | | bacteria Contact acid with teeth: 1. chronic vomiting or acid reflux from GI disorders 2. consumes large amounts of acid foods 3. occupational exposure Regurgitated acids attack lingual surfaces; diet--labial; industrial– all surfaces Radiolucent defect on the crown Wen. Chen Wang

43 Resorption -Removal of tooth structure by odontoclast l Chronic infection (inflammation), excessive pressure and function, tumors and cysts Wen. Chen Wang

44 Internal Resorption - within the pulp chamber or canal, involves resorption of surrounding dentin, results in enlarged pulp space Ref. 1 Wen. Chen Wang

45 Internal Resorption Ref. 1 Wen. Chen Wang

46 External Resorption -outer surface of tooth resorbed, most commonly in root surface | | Localized inflammatory lesions, reimplanted teeth, tumor & cyst, excessive mechanical(orthodontic) and occlusal forces, impactions Common sites : apical & cervical (lateral root surface) Wen. Chen Wang

47 Apical ER Lateral root surface ER Ref. 1 Wen. Chen Wang

48 Secondary Dentin - Dentin deposited in pulp chamber after primary dentin formatted completely | Normal aging process | tertiary dentin: pathologic condition after chronic trauma | Reduction in size of pulp chamber and canals | Begins in the region adjacent to source of stimuli and alters normal shape of chamber Ref. 1 Wen. Chen Wang

49 Pulp Stone -- Foci of calcification in the | | pulp R-O within pulp chambers or root canals or extending from pulp chamber into root canals, most common in molars No uniform shape or number Ref. 1 Wen. Chen Wang

50 Pulpal Sclerosis - Diffuse calcification in pulp chamber and canals | Correlation strongly with age | Generalized, ill defined collection of fine RO throughout pulp chamber and canals Ref. 1 Wen. Chen Wang

51 Hypercementosis -Excessive deposition of cementum on roots 1. supraerupated tooth after opposing tooth loss 2. periapical inflammatory lesions 3. hyperocclusion or fractured 4. Paget’s disease 5. hyperpituitarism | Smooth or irregular enlargement of root with lamina dura and PDL space Ref. 1 Wen. Chen Wang

52 Summary DEVELOPMENTAL ABNORMALITIES ACQUIRED PATHOLOGIC CONDITIONS n n NUMBER OF TEETH SIZE OF TEETH ERUPTION OF TEETH ALTERED MORPHOLOGY OF TEETH u Fusion(synodontia) u Concresence u Gemination(twinning) u Taurodontism u Dilaceration u Dens in dente (dens invaginatus) u Dens evaginatus u Amelogenesis imperfecta u Dentin dysplasia u Enamel pearl u Talon cusp u Turner’s hypoplasia (Turner’s tooth) u Congenital syphilis n n n Attrition Abrasion Tooth brushong injury Dental floss injury Erosion Resorption Internal resorption External resorption Secondary dentin Pulp stone Pulpal sclerosis Hypercementosis Wen. Chen Wang