Anomalies of Teeth PDF

Anomalies of Teeth  Anomalies of teeth development I-Anomalies in number of the teeth: 1-Anodontia, total or partial 2-Supernuerary teeth. II-Anomalies in size: Micro or macrodontia III-Anomalies in shape: 1-fusion, 2-gemenation, 3-dilaceration 4-dens in dente, 5-pulp...

Anomalies of Teeth  Anomalies of teeth development I-Anomalies in number of the teeth: 1-Anodontia, total or partial 2-Supernuerary teeth. II-Anomalies in size: Micro or macrodontia III-Anomalies in shape: 1-fusion, 2-gemenation, 3-dilaceration 4-dens in dente, 5-pulp stone, 6- enamel pearl 7-taurodontism, 8-concrescence. 9- hypercementosis IV-Anomalies in structure: Amelo or dentinogenesis imperfecta V- Miscellaneous I-Anomalies in number of the teeth: 1-Anodontia, total or partial 2-Supernuerary teeth.  Congenitally Missing Teeth Partial Anodontia Hypodontia: Few missing teeth Oligodontia: More than half the number missing in any dentition (perm. or dec.) Complete Anodontia Anodontia: All teeth missing  I-Anomalies in number of the teeth: Partial anodontia (hypodontia) Frequency of congenitally missing permanent teeth, in the following order: – 3rd molars – Maxillary 2nd premolars – Mandibular 2nd premolars – Maxillary laterals – Mandibular canines – Other absence of permanent tooth buds of second premolars Hypodontia Hypodontia Hypodontia Retained last deciduous molar and missing lower second premolar Retention of lower 7 by the horizontally impacted 8 Impacted lower 4 Ankylosed 5 at the floor of maxillary sinus  Oligodontia or Anodontia Hereditary ectodermal dysplasia Therapeutic radiation to jaws at an early age  Hereditary Ectodermal Dysplasia Affects ectodermally-derived structures Thin, dry skin Partial or complete absence of sweat glands Sebaceous glands, hair follicles defective or absent Thin, scanty, blond hair Depressed bridge of nose Hereditary Ectodermal Dysplasia (Cont.) Complete or partial absence of permanent teeth (rarely, deciduous) Cone shaped anterior teeth Hypoplasia of occlusal or incisal enamel Hypoplasia of minor salivary glands resulting in xerostomia Hereditary Ectodermal Dysplasia Hereditary Ectodermal Dysplasia Jaw Irradiation at Early Age Senile atrophy of alveolar process Retained upper third molar in edentulous patient Retained lower 5 in edentulous ridge Supernumerary (Hyperdontia) 80-85% of all supernumerary in maxilla Named in maxilla only. Not named in mandible Mesiodens. Midline of maxilla. 85-90% Paramolars. Buccal or lingual to maxillary molars Distomolars (4th molars, distodens). Distal to maxillary 3rd molars Mesiodens Paramolar Distodens Multiple Supernumerary Teeth Cleidocranial dysplasia Gardner’s syndrome  Cleidocranial Dysplasia Multiple impacted/unerupted permanent teeth Retention of primary teeth Multiple supernumerary teeth Complete or partial absence of clavicles bilaterally Cleidocranial Dysplasia Cleidocranial Dysplasia  Gardner’s Syndrome Multiple colo-rectal polyps, high potential for carcinomatous change Multiple osteomas of bones Multiple sebaceous cysts Multiple soft tissue tumors (fibromas, lipomas, fibrosarcomas ) Multiple supernumerary teeth and/or odontomas Multiple impacted teeth Gardner’s Syndrome Supernumerary Roots Supernumerary Roots II-Anomalies in size: 1-Microdontia 2-Macrodontia  Microdontia Smaller than average Most commonly involved: – Maxillary 3rd molars – Maxillary laterals (sometime called “peg” laterals) – Maxillary premolars Microdontia Microdontia Macrodontia (larger than normal) MACRODONTIA II-Anomalies in shape: 1-Gemenation, 2-Fusion 3-Dilaceration 4-Dens In Dente 5-Pulp Stone 6-Enamel Pearl 7-Taurodontism 8-Concrescence 9- Hypercementosis  Gemination During development, single tooth germ attempts to divide into two. Usually results in bifurcation of a part of crown Unilateral or bilateral Normal complement of teeth is present Gemination Gemination  Gemination of lower 7 & 8: The two molars developed in a single follicular sac  Fusion During development, union of two adjoining tooth germs Clinically, identical to gemination, i.e, bifurcated crown. However, One tooth is missing Unilateral or bilateral Primary or permanent dentition Fusion Fusion  Concrescence Union of two teeth after they are completely formed Joined with cementum  Dilaceration Unusual angulation of roots Dilaceration Root Bifurcations Dens Invaginatus (Dens-in-dente) Invagination of a layer of enamel and dentin into pulp. Creates a potential space for entrapment of food debris and bacteria. Wide variation in size. Clinically, either not discernible or seen as a prominent pit at the cingulum. Dens Invaginatus (Dens-in-dente) Frequently, caries, pulp exposure and periapical pathology develops without any clinical indication. Most frequently (95%) in maxillary lateral incisor. Bilateral in half the cases. Prophylactic restoration recommended. Dens Invaginatus Dens Invaginatus Dens Evaginatus Dens in dente: Tooth within tooth Taurodont: Typically elongated pulp chamber with roots Taurodontia  Taurodontia Bifurcation of molar pulp chamber into root canals displaced apically, resulting in an extremely large pulp chamber and short root canals. Usually in permanent molars. Most patients asymptomatic; does not require treatment. Frequently, bilateral. Taurodontia Taurodontia Differential Dx: Large Pulp Taurodontia Hypophosphatemic vitamin D-resistant rickets Hypophosphatasia Odontodysplasia  Hypophosphatemic Vitamin D- resistant Rickets X-linked dominant trait Hypophosphatemia- due to decreased renal tubular reabsorption of inorganic phosphates Hyperphosphaturia Normal serum calcium Alkaline phosphatase may be elevated  Hypophosphatemic Vitamin D- resistant Rickets (cont.) Large pulp chambers, pulp horns extending to DEJ Single or multiple periapical abscesses Signs of rickets, i.e.,osteomalacia, skeletal deformities, delayed eruption of teeth, bowing of legs. Resistant to therapeutic doses of Vit. D Hypophosphatemic Vitamin D- resistant Rickets (cont.) Hypophosphatemic Vitamin D- resistant Rickets (cont.)  Hypophosphatasia Autosomal recessive Decreased enzyme alkaline phosphatase in serum and tissues Lack of cementum on root surface Loss or mobility of primary teeth Crestal bone loss Enlarged pulp chambers Greater predilection for pulp exposure and periapical pathology Skeletal changes resembling rickets Hypophosphatasia Hypophosphatasia Odontodysplasia Not hereditary Severe hypoplasia of enamel and dentin Usually regional, may be generalized Affects primary and permanent teeth Ghost-like appearance of teeth Odontodysplasia  Hypercementosis Excessive deposition of cementum on the root surface(s). In most cases, the cause is unknown, the patient is asymptomatic and no treatment is required. May be seen in patients with Paget’s disease and hyperpituitarism (acromegaly). Hypercementosis Hypercementosis  Generalized Hypercementosis Paget’s Disease of Bone Acromegaly Paget’s Disease of Bone Paget’s Disease of Bone Hypercementosis Pulp stones Enamel Hyperplasia (enamel pearl) Enamel Hyperplasia Enamel Hyperplasia Enamel pearl IV-Anomalies in structure: Amelogenesis imperfecta Amelogenesis imperfecta Radiographic series of amelogenesis imperfecta case Dentinogenesis imperfecta in 11-years old female, Note the typical disproportion between the crowns and roots Note the obliterated pulp chambers and canals Shell tooth This is one form of dentinogenesis imperfecta in which the roots do not form at all and the pulp chamber appears to be enlarged Odontogenesis imperfecta It is malformation of teeth and disturbance in eruption patterns usually accompanied with osteogenesis imperfcta Pulp champers with various sizes All parts of teeth are involved The malformed teeth do not erupt. Idiopathic resorption on maxillary and mandibular anterior teeth Accessory canal Accessory canal  Ankylosis Periodontal ligament disappears and tooth root fuses to bone. Cause? Ankylosis Ankylosis Axial Rotation Migration Migration  Migration A tooth is missing. Another tooth of the same or similar morphology is present. Migration Retained lower molar in abnormal position Drifting Transposition Transposition Transposition  Unerupted Teeth Embedded: Teeth do not erupt due to lack of eruptive force Impacted: Teeth do not erupt due to unusual angulation, location, lack of space or obstruction  Impacted Teeth Vertical Mesioangular Distoangular Horizontal Inverted Multiple Impacted Tooth Impacted Tooth Impacted Tooth Impacted Tooth Impacted Tooth Impacted Teeth Fractures Root fracture Foreign bodies  Foreign bodies No comment Hollow needles for radiotherapy of cancer of paroted gland Deposition of filling materials in the vestibule Foreign Bodies Failure apicectomy successful apicectomy Atraumatic extraction of third molar Healing after extraction 6 months later Errors of intraoral films Films with errors should be avoided due to the following reasons: Retake will lead to:  Expose the patient to unnecessary radiation.  Waste film & time (money).  Interfere with accurate interpretation and diagnosis. Table showing Subjective Quality Rating by Group  Causes of faulty radiograph The majority of the errors produced can be categorized into three groups: I. Technique & Projection errors. II. Exposure errors. III. Processing errors. Technique & Projection errors: a. Patient preparation error: Radiopaque artifact Blurred image b. Film placment artifact: Reversed film Dot artifact Apices cut off Crown not shown Dropped film corner Area of interest not shown Black line Distortion c. Projection errors: Incorrect vertical angulation. Incorrect horizontal angulation PID alignment artifact Technique & Projection errors Patient preparation error Radiopaque artifact Dental appliances, jewelry & eye glasses left in the mouth during exposure will appear as radiopaque artifact superimposed over the dental image. Correction: all this items should be removed before placing of the film  The patient is still wearing a pair of glasses. A nose Stud has been left in. Patient preparation error Blurred image Movement of the film, patient or X-ray tube head during exposure will result in a blurred image. Correction: the operator should explain for the patient & remind him to remain motionless during exposure. Technique & Projection errors b. Film placment artifact  Reversed film Low density with herring bone, tire-track or dotted pattern, as a result of directing the X-ray through the lead foil side of the film back. Dot artifact The identification dot produce a circular radiolucent artifact on the final radiograph. This may interfere with interpretation of the apical areas of the teeth. Correction: Correct placement of the embossed dot Apices cut off Occur when the film is not positioned apically enough to record the entire tooth. Crown not shown There is no enough film extending occlusally. Dropped film corner The film edge is not placed parallel to the occlusal surface of the teeth. Area of interest not shown This is the result of not placing the film to cover all the teeth in the area of interest and not centralizing the film over the area of interest. Black line Due to excessive bending of the film prior to its placement inside the patient’s mouth (pressure causes ionization of silver halide upon processing will be darker). Distortion Due to bending of the film to eliminate the patient’s discomfort specially in lower premolar area and upper central incisors. NORMAL DISTORED c. Projection errors  Vertical Angulation Errors Results in an image of the tooth that is longer or shorter than the actual tooth. Primarily seen when using the bisecting angle technique. Elongation  Elongation Not enough vertical angulation. (The White arrow points to the end of tooth image; the white lines represent the actual length of the tooth). Foreshortening Foreshortening Too much vertical angulation. (The arrow points to the end of the tooth; the white lines represent the actual length of the tooth).  Overlap (Incorrect horizontal angulation)  Incorrect Horizontal Angulation If the x-ray beam is not perpendicular to the line connecting the buccal surfaces of the teeth, overlap between the buccal surface of one tooth and the lingual surface of the adjacent tooth occurs. film  lingual buccal Overlap (incorrect horizontal) Overlap of crowns (black arrows) and roots (red arrow) All contacts overlapped  Cone Cutting X-ray beam not centered on film, leaving part of film unexposed. Unexposed part of film (below dotted line) Cone cutting Cone cutting (bisecting angle technique)  Cone Cutting (bitewing technique) Cone cutting Exposure errors II. Exposure errors. Blank image. Low density image. High density image. Image with high and low contrast Exposure errors Blank image A film that didn’t receive radiation will have no image and will appear clear  High Density image Errors in machine operation:  Excessive milliamperage  Excessive kilovoltage  Excessive time  Film_ source distance too short processing errors:  Accidental exposure to light  Inadequate fixation  High developer temp.  High developer conc.  High developing time Low density (faint) image (too light) Exposure errors  less milliamperage  less kilovoltage  less exposure time  Film_ source distance too long processing errors: Old developer solution Low developer temp. Low developing time Low developer conc. Processing errors Chemical errors: Light image. Dark image. Reticulation. Black spot or patch. White spot or patch. Yellowish brown discoloration. Film Handling errors: Developer cut off Fixer cut off Finger nail artifact Smudge. Static electricity Processing errors Chemical errors Reticulation. Appear as cracked on the film. Causes: Increased fixer acidity and long time fixation. film subjected to a sudden temperature changes between the developer and water. Processing errors Chemical errors Black spot or patch Developer contamination before immersion into the developer solution. Processing errors Chemical errors White spot or patch Contamination with fixer before processing Processing errors Chemical errors Yellowish brown discoloration Exhausted solution or insufficient rinsing Processing errors Film Handling errors Finger nail artifact Black or whit crescent shape mark due to rough handling of. Processing errors Film Handling errors Developer cut off. A straight white border. The film may not be completely immersed in the developer solution. Processing errors Film Handling errors Fixer cut off A straight black border. The film may not be completely immersed in the fixer solution. Processing errors Film Handling errors Smudge (finger print) When the film touched by fingers contaminated with developer or fixer Film Fog: A-Light. 1. Light leakage to the dark room due to improper safety of the room or improper safe light as a result of cracked bulb or unsafe filter. 2. Prolonged exposure of the film to the safe light. 3. Short distance between the film and safe light. B-Storage: 1. Expired films. C-Chemicals. 1. Developer contamination. 2. Dirty processing tanks. THANK YOU