Abnormalities of Teeth (Jones) Flashcards
- Usually caused by periapical inflammatory disease in an overlying deciduous tooth (often the deciduous molars)
- Usually affects the permanent bicuspids
- White, yellow, or brown discoloration
- May involve the entire crown
- May affect the permanent maxillary central incisors as a result of traumatic injury to the deciduous central incisors
Turner Hypoplasia
-Enamel hypoplasia that affects the anterior and posterior teeth
-Due to congenital syphilis; rarely seen today
-Anterior teeth: Hutchinson incisors
(Screwdriver shaped crowns with a constricted incisal edge)
-Posterior teeth: Mulberry molars
(Disorganized occlusal surface anatomy resembling a mulberry)
Syphilitic Hypoplasia
- Loss of tooth structure caused by tooth-to-tooth contact during occlusion and mastication
- More noticeable with age
- May be accelerated by poor quality or absent enamel, premature contacts, or intraoral abrasives and grinding habits
- May affect the deciduous and permanent dentitions
- Usually affects the incisal and occlusal surfaces
- Pulp exposure and sensitivity are rare
Attrition
- Pathologic loss of tooth structure secondary to the action of an external agent
- Most common cause is tooth brushing
- Other causes include pencils, toothpicks, pipe stems, and bobby pins
- More common on the side of the arch opposite the dominant hand
- Pulp exposure and dentin sensitivity are rare
Abrasion
- Loss of tooth structure caused by a chemical process
- Usually due to exposure to an acid found in foods, drinks, medications, swimming pools, or chronic involuntary/voluntary regurgitation
- Commonly affects the facial surfaces of the maxillary anterior teeth - due to dietary sources of acid
- Involvement of the posterior teeth often occurs on the occlusal surface causing the edges of metallic restorations to be above the level of the tooth structure
- Involvement of the lingual surfaces of the maxillary anterior teeth and the occlusal surfaces of the posterior teeth suggests the cause is due to regurgitation of gastric secretions
Erosion
-Cessation of eruption after emergence
-Occurs because of an anatomic fusion of cementum with the alveolar bone
-Cause is unknown; may be due to trauma, injury, or chemical or thermal irritation
-Any age; peak incidence is 8-9 years of age
-Most commonly affected tooth: mandibular deciduous first molar
-Occlusal plane is below adjacent dentition
-Absence of the periodontal ligament space
-May lead to occlusal and periodontal problems
-Treatment and prognosis
(Teeth fail to respond to orthodontic forces;
Prosthodontic therapy;
Extraction and space maintenance)
Ankylosis
-Lack of development of one or more teeth
-Often due to genetic or environmental factors
-F > M
-Permanent dentition > deciduous dentition
-Permanent dentition: third molars > second premolars > lateral incisors
-Deciduous dentition: mandibular incisors
-Positively correlated with microdontia
-Anodontia: patient should be evaluated for ectodermal dysplasia
-Treatment and prognosis
(Prosthodontic therapy)
Hypodontia
-Increased number of teeth: supernumerary teeth
-Most represent examples of single-tooth hyperdontia
(Permanent dentition > deciduous dentition;
90% in the maxillary anterior region;
Maxillary incisors > maxillary fourth molars > mandibular fourth molars;
Unilateral > bilateral)
-Positively correlated with macrodontia
-Most cases arise in the 1st and 2nd decades of life; M > F
-Several specific clinical forms:
(Mesiodens: maxillary anterior incisor region;
Paramolar: lingual or buccal to a molar tooth;
Natal teeth: present at birth (prematurely erupted deciduous teeth))
-Treatment and prognosis
(Removal of the accessory tooth;
May cause aesthetic and functional problems)
Hyperdontia
-Teeth are physically smaller than normal
-Most often involves the maxillary lateral incisors followed by the third molars
-Treatment and prognosis
(None necessary unless for aesthetic considerations)
Microdontia
-A single enlarged tooth in which the tooth count is normal when the anomalous tooth is counted as one
-May involve the primary and permanent dentitions
-Most common in the anterior maxillary region
-Treatment and prognosis
(Deciduous dentition:
May result in crowding, abnormal spacing, and delayed or ectopic eruption of the permanent teeth;
Permanent dentition:
Extraction or cosmetic shaping)
Gemination
-A single enlarged tooth in which the tooth count reveals a missing tooth when the anomalous tooth is counted as one
-May involve the primary and permanent dentitions
-Most common in the anterior mandibular region
-Treatment and prognosis
(Deciduous dentition:
May result in crowding, abnormal spacing, and delayed or ectopic eruption of the permanent teeth;
Permanent dentition:
Extraction or cosmetic shaping)
Fusion
- Union of two adjacent teeth by cementum alone without confluence of the underlying dentin
- May be developmental or postinflammatory
- Most common in the maxillary posterior region
- Treatment and prognosis: None or surgical removal
Concrescence
-Well-delineated additional cusp located on the surface of an anterior tooth and extends at least half the distance from the cementoenamel junction to the incisal edge
-Majority occur in the permanent dentition: maxillary lateral incisor > maxillary central incisor
-Deciduous dentition: maxillary central incisor
-The accessory cusp usually projects from the lingual surface of the affected tooth
-Most contain a pulpal extension
-M = F; unilateral or bilateral
-Treatment and prognosis
(Mandibular teeth: no therapy;
Maxillary teeth: interfere with occlusion and should be removed)
Talon Cusp
-Deep surface invagination of the crown or root that is lined by enamel
-Two forms: coronal and radicular
-Coronal > radicular
-Most often affects the permanent lateral incisors > central incisors > premolars > canines > molars; maxillary predominance
-Large invaginations may resemble a tooth within a tooth
-Radiographs demonstrate a dilated invagination lined by enamel
-Treatment and prognosis
(Opening should be restored to prevent caries;
If pulpal communication or pulpal pathosis is evident, endodontics should be performed;
Large invaginations may require extraction)
Dens Invaginatus or Dens in Dente
- Enlargement of the body and pulp chamber of a multirooted tooth with apical displacement of the pulpal floor and bifurcation of the roots
- Affected teeth tend to be rectangular in shape
- Unilateral or bilateral
- Permanent teeth > deciduous teeth; M = F
- Treatment and prognosis: None
Taurodontism
-Nonneoplastic deposition of excessive cementum that is continuous with the normal radicular cementum
-May be due to:
(Abnormal occlusal trauma;
Adjacent inflammation;
Unopposed teeth)
-May be isolated or involve multiple teeth
-Most often involves mandibular molars
-Usually occurs in adulthood
-Radiographs demonstrate an enlarged root surrounded by the periodontal ligament space
-Histopathologic features:
Excessive deposition of cellular and acellular cementum
-Treatment and prognosis:
None;
Difficulties arise with an extraction
Hypercementosis
-An abnormal angulation or bend in the root of a tooth
-Majority arise after an injury that displaces the calcified portion of the tooth germ
-May occur secondary to an adjacent cyst or tumor
-Any tooth may be affected
-Treatment and prognosis:
(Depends on the severity of the deformity;
None, extraction, root canal therapy)
Dilaceration
Cause of Turner Hypoplasia & which teeth it affects
- Periapical inflammatory disease in overlying deciduous tooth (often deciduous molars)
- Permanent bicuspids (Max. central incisors as a result of traumatic injury to decid. cen. incisors)
