Module 1: Abnormalities of Teeth PDF

MODULE 1: ABNORMALITIES OF TEETH 2. ANODONTIA - Synonym: Anodontia Vera - Congenital absence of teeth ALTERATIONS IN SIZE...

MODULE 1: ABNORMALITIES OF TEETH 2. ANODONTIA - Synonym: Anodontia Vera - Congenital absence of teeth ALTERATIONS IN SIZE - Failure of the tooth buds to develop - “True Anodontia” 1. MICRODONTIA - May involve both permanent and deciduous - Hypoplasia of teeth TYPES / VARIETIES: - Less developed 1. Total or Complete Anodontia - Peg-shaped - All teeth are missing - Due to less enamel development - Failure of entire dentition to develop - Often associated with Hereditary 2. MACRODONTIA Ectodermal Dysplasia - Hyperplasia of teeth 2. True Partial Anodontia - Megadontism - One or several teeth are missing - Gigantism - Absence of tooth buds - Maybe associated with Hereditary A. TRUE GENERALIZED OR Ectodermal Dysplasia PROPORTIONAL Hypodontia - Absence of 1-6 - Size of jaw nor proportional to the teeth face Oligodontia - More than 6 - Teeth = jaw teeth are missing B. RELATIVE GENERALIZED OR 3. Pseudoanodontia DISPROPORTIONAL - Multiple unerupted teeth - Teeth ≠ jaw - Impaction or delayed eruption C. FOCAL OR LOCALIZED - Formed but failed to erupt - Single tooth is abnormal in size 4. Induced Anodontia - Result of extraction or exfoliation of teeth - Due to extraction ALTERATIONS IN NUMBER AND ERUPTION 3. IMPACTION 1. SUPERNUMERARY TEETH - Tooth is clinically absent - Synonym: Hyperdontia - Due to lack of space or eruptive force - Excess in normal number of dentition ETIOLOGY: 2 TYPES BASED ON ANATOMY: 1. Lack of space due to crowding a. True Supernumerary 2. Rotation of tooth buds - Normal anatomy 3. Ankylosis - Can be identified 4. 3rd molar and maxillary canine most b. Accessory or Rudimentary Tooth common impacted teeth - Non-identifiable POSITIONS: CLASSIFICATION BASED ON LOCATION: A - Mesioangular 1. Mesiodens B - Distoangular - Most common C - Horizontal Impaction - Located between maxillary central incisors TYPES: - Can cause diastema 1. Partial 2. Maxillary 4th Molar 2. Complete - 2nd most common 3. Multiple 3. Peridens - Erupts outside the arch SYMPTOMS: 4. Paramolar 1. Pericoronitis - Erupts on the buccal, lingual or - Most common proximal - Inflammation of gingiva covering the *Paramolar Tubercle* tooth - Fused with permanent maxillary molar CLASSIFICATION: ALTERATIONS IN SHAPE AND FORM Class I - Sufficient amount of space between the ramus and distal 2nd molar ANOMALIES IN CROWN Class II - Space between the mandible and distal of 2nd molar is less than 1. FUSION mesiodistal diameter of the crown of - 2 tooth bud attached 3rd molar - 2 developing tooth germs, resulting in single Class III large tooth - All of the 3rd molar is located within - 2 teeth become fused by enamel and dentin the ramus - Common in mandibular anterior - Occurs during the development Position A - Highest portion of impacted tooth is TYPES: level with the occlusal line of 2nd 1. Complete Fusion molar - Both crown and root Position B 2. Partial Fusion - Highest portion of impacted tooth is - Crown only below the occlusal line but above cervical line of 2nd molar ETIOLOGY: Position C 1. Trauma, pressure, sudden force - Highest portion of impacted tooth is 2. Hereditary below the cervical line of 2nd molar 2. GEMINATION OW TWINNED TOOTH 1. Mesioangular - Most common - 1 tooth bud developed and attempted to - 3rd molar crown in contact with divide into 2 distal surface of the root or crown of - Crown of a tooth appears split or twinned 2nd molar 2. Distoangular 3. TAURODONTISM - 3rd molar crown pointing distally - Teeth with elongated crowns towards the ramus - Root is rectangular 3. Vertical - Furcation is apically displaced - Normal vertical position - Difficult to find the root canal - Can’t erupt due to lack of space of - Doing RCT is blind working eruption 4. Horizontal - May lie at any level within the bone 5. Inverted 4. TALON’S CUSP OR SUPERNUMERARY CUSP - 3rd molar is inverted - Overdeveloped cingulum - Crown pointing towards the inferior - Extra cusp / extra root border of the mandible - Contains a horn of pulp tissue 6. Buccoangular - Problems in terms of aesthetics, caries - 3rd molar crown directed towards control and occlusal accommodation the cheeks and roots on the lingual - May cause anterior open bite 7. Linguoangular - Common in maxillary central incisors - 3rd molar crown directed towards the lingual and roots on the cheeks ETIOLOGY: - Due to over stimulation of inner dental epithelium 5. LEONG’S PREMOLAR OR DENS EVAGINATUS - Exclusive in premolar - Anomalous tubercle or cusp located in center of the occlusal surface - Early exposure of accessory pulp horn ETIOLOGY: - Invaginatus of extrusion of the inner dental epithelium  6. DENS INVAGINATUS OR DENS EN DENTE 6. HYPERCEMENTOSIS - Tooth within a tooth - Overgrowth of cementum - There’s exaggeration of the lingual pit 7. SUPERNUMERARY ROOTS Notched or Hutchinson Incisor - Tooth is narrower on the cutting - Excess in number of roots edge - Scre-driver or barrel form - No contact with adjacent teeth DEFECTS OF ENAMEL - Middle lobe is absent - Infants may be born with syphilis Mulberry Molar AMELOGENESIS IMPERFECTA - Occlusal surface is pinched together - Other name: Hereditary Enamel Hypoplasia - Common in mandibular molars - Defect happen during amelogenesis - Many underdeveloped cusps - Due to malfunction of proteins in enamel - Mutations in the enamelin gene ANOMALIES IN ROOTS CLINICAL FEATURES: - Abnormal color: yellow, brown, gray 1. CONCRESCENCE - Enamel is thin or soft - 2 normally separated teeth become fused in - Higher risk to dental cavities cementum - Hypersensitive to temperature changes - Common in maxillary 2nd and 3rd molars ETIOLOGY: ETIOLOGY: Local Factors: - Trauma - Trauma - Overcrowding - Abscess formation Systemic Factors: - Rickets 2. ENAMEL PEARL OR ENAMELOMA - Syphilis - Appears as tiny globule - Birth trauma - Found in furcation area - Fluoridisation: topical application - Common in maxillary molars - Fluoridation: water supply ETIOLOGY: TREATMENT: - Arises from a small group of misplaced - Children: stainless steel crowns ameloblast - Adult: porcelain TYPES: 3. DILACERATION 1. Enamel Hypoplasia - Bent as much as 90 degrees - Quantitatively defective enamel - Normal hardness ETIOLOGY: - Insufficient enamel matrix count - Due to trauma 2. Enamel Hypocalcification - Qualitatively defective enamel CLINICAL IMPLICATION: - Normal amount of enamel - Difficult to extract - Hypomineralization - RCT - Enamel is softer than normal 4. FLEXION - Involves apical 3rd of the root - Bent less than 90 degrees 5. ANKYLOSIS - Embedded in bone SIGNS: - Appears submerged because the root don;y grow at same rate as other - Not aligned with other teeth  RADIOGRAPHIC FEATURES: DEFECTS OF DENTIN 1. Coronal pulps are enlarged having a Permanent: “thistle tube” 1. DENTINOGENESIS IMPERFECTA Primary: total obliteration of pulp chamber - Defective dentin - Not sex linked TREATMENT: - Affects both primary and permanent - Retention of teeth dentition CLINICAL FEATURES: 3. REGIONAL ODONTODYSPLASIA 1. Teeth are discolored from blue-gray to - Ghost teeth brownish violet or yellowing brown - Uncommon developmental abnormality of 2. Teeth exhibit translucent or opalescent hue teeth 3. Enamel fractures easily - Permanent teeth are more affected than 4. Dentin undergoes rapid attrition primary teeth - Maxillary anterior teeth are affected more TYPES: than the other teeth Type I - Females are more affected than males - Deciduous teeth are involved Type II CLINICAL FEATURE: - Both dentitions are involved - Eruption of teeth is delayed or does not Type III occur - Brandywine type / shell teeth RADIOGRAPHIC FEATURES: RADIOGRAPHIC FEATURES: - Thinness and poo mineralization quality of Type I and II enamel and dentin - Closure of pulp chambers - Short roots, open apical foramina and - Dentin is too bulky enlarged pulp chambers Type III - Thin enamel and dentin ETIOLOGY: - Spaces are big - Unknown - Trauma 2. DENTIN DYSPLASIA - Nutritional deficiencies - Infections - Rootless tooth - Rare condition TREATMENT: - Dominant genetic disorder of teeth - Extraction - RCT is not an option TYPES: - Caries prevention Type I or Radicular Type - Root problem CLINICAL FEATURES: 1. Both dentitions are normal color and shape 2. Greater resistance to caries than normal teeth RADIOGRAPHIC FEATURES: 1. Roots are short 2. Deciduous: pulp chambers and root canals are completely obliterated 3. Permanent: residual fragments of pulp cavity appears as chevrons or crescent shaped Type II or Coronal Type - Crown problem CLINICAL FEATURE: - Color of primary dentition is opalescent, permanent is normal