dental Flashcards
- Dental inclusion and root ankylosis
Dental inclusion
Definition: Tooth eruption is halted before its emergence on the alveolar ridge. The tooth is surrounded by bony tissue and is unable to erupt.
Etiology:
Lack of parallelism between the tooth bud and the eruption axis
Ectopic position of the tooth bud
Gingival fibromatosis, tumors, cysts on the eruption tract
Pathology:
- Position of the included tooth’s axis
Vertical
Oblique (mesio – angular, distal – angular)
Horizontal
Inverted
Complications:
Dental «crowding»
Resorbtion of the roots of neighbouring teeth
Changes in the eruption order and in the position of neighboring teeth
Inflammation in the involved region
Development of a dentigerous cyst
Included teeth with complications and clinical manifestations must be surgically removed!!
Radicular ankylosis
Definition: Tooth eruption is halted after its emergence on the alveolar ridge. Bony union of the radicular surface of a tooth to the surrounding alveolar bone in an area of previous partial root resorption.
It occurs in the first two decades of life
Microscopy:
! Fusion between cementum and the alveolar bone with the disappearance of periodontal structures
Etiology:
Idiopathic
Hereditary
Macroscopy:
The incisal margins and occlusal surfaces of the ankylosed teeth are located below the level of adjacent teeth: sub-occlusion.
Diagnosis Rx:
Disappearance of the alveolar ligament
Complications:
Adjacent teeth lean towards the ankylosed one
The antagonist tooth (from the opposite arcade) develops excessively
Bone fractures in case of extraction – previous diagnosis of ankylosis is required
- Dental transposition and ectopy
Transposition
Growth of a tooth in the place of another one on the same arch, and vice versa.
E.g.: the first molar in the place of the second molar
Ectopy
Development of teeth outside the dental arches.
Examples:
Supranumerary teeth
Included in gingiva, the mental protuberance, soft palate and in the spheno-maxillary fissure
Sometimes normal teeth with abnormal location
- Hypodontia and anodontia
Hypodontia/Partial oligodontia Absence of a few teeth . Less than five for hypodontia and more than 6 for partial oligoodntia. Differiential Diagnosis Frequently hereditary origin Frequently associated with MICRODONTIA
Anodontia/agenesis/total oligodontia
Total absence of teeth.
Rare; since birth.
Frequently a part of HEREDITARY ECTODERMAL DYSPLASIA
- Hyperdontia (mesiodens, paramolar and distomolar)
Hyperodontia
The number of teeth is higher than normal
AD,
Associated with MACRODONTIA
MESIODENS= most common supernumary tooth, located in the maxilla’s midline.
90% of supranumerary teeth
Between the central superior incisors (75%)
PARAMOLARS= Paramolar is a supernumerary molar usually small and rudimentary, most commonly situated buccally or palatally to one of the maxillary molars.
The fourth molar/DISTOMOLAR/distodens= supernumary tooth in a distal position in relation to the third molar
- Hypercementosis
HYPERCEMENTOSIS = Hypercementosisis anidiopathic, non-neoplasticcondition characterized by the excessive buildup of normalcementum(calcified tissue) on the roots of one or more teeth.
Growth lines which are parallel to the root
Increases with age – especially in the apical region in order to compensate for the occlusal damage.
- Dilaceration
DILACERATION = Dilacerationis a developmental disturbance in shape of teeth. It refers to an angulation, or a sharp bend or curve, in the root or crown of a formedtooth.
Increased curvatures or angulations of the roots or of root-crown junctions
Causes :
Traumas during root formation:
- Germination/Fusion
GERMINATION/FUSION
Large teeth with two crowns, more or less separated or fused = tooth with doubled dimensions
GERMINATION = Incomplete division (cleavage) of a tooth bud→ two crowns, common root. The divided (double) tooth is considered as a single one→ the number of teeth is normal.
FUSION = Fusion between the dentin of two adjacent tooth buds→ two fused crowns on one or two roots.
Causes: traumatc crowding, lack of space
- Concrescence
CONCRESCENCE = Reuniting of the roots of two already formed adjacent teeth. Exclusive through cementum, the dentin remaining distinct Etiology: Growth disturbances Trauma Hypercementosis caused by chronic inflammation Deep caries Open root canals Periapical inflammatory lesions
- Dental invagination and taurodontism
DENS INVAGINATUS = «dens in dente» = Invagination of the dental crown in the pulp chamber or the root pulp (radicular dens invaginatus). The outer surface folds inwards.
Fusion of two dental buds
Enamel – towards inside
Dentin – towards outside
DENS IN DENTE
It opens through a very prominent dental cingulum (foramen caecum), with a hypomineralized enamel.
Consequences:
Acummulation of food, microbial plaque at the opening => caries, pulpitis, pulp necrosis – quickly
TAURODONTISM = is a condition found in themolar teethof humans whereby the body of the tooth andpulpchamber is enlarged vertically at the expense of the roots.
Very large pulp chamber
The neck diameter of the tooth is larger than normal
+ The root division is placed lower, close to the apex
Diagnosis Rx
Three types:
Hypotaurodontism
Mesotaurodontism (moderate)
Hypertaurodontism (severe)
- Amelogenesis imperfect: hypoplastic A.I.
HEREDITARY ENAMEL DYSPLASIAS!! = AMELOGENESIS IMPERFECTA (A. I.)
Ectodermal anomaly – dysfunction of the adamantine organ (of the ameloblasts)
It doesn’t involve the dentin (mesodermal origin)
Genetically inherited: AD (most frequent), AR, X-linked
Involves the enamel of all the teeth
HYPOPLASTICA.I. – two forms:
ENAMEL APLASIA:
The teeth which remain included are often resorbed
If the teeth erupt:
No enamel deposits (Rx)
Covered with dentin
Yellow-brown colour
Rough surface
ENAMEL HYPOPLASIA:
Reduced production of protein matrix
Normal degree of mineralization
- Secondary enamel dysplasia: Turner hypoplasia (local infection), dental trauma, fluorosis, congenital syphilis
TURNER HYPOPLASIA !!!
Definition: Hypoplastic enamel on the crown of a permanent tooth due to the periapical inflammation of the subjacent temporary tooth!!!
TRAUMAS:
= Enamel hypoplasia in a permanent tooth, when the subjacent temporary tooth is traumatized
FLUOROSIS: developmental disturbance of dental enamel caused by excessive exposure to high concentrations offluorideduringtooth development.
Excess of fluorine → Enamel hypomaturation → increased porosity
CONGENITAL SYPHILIS
Spirochetes enter the fetal circulation after the 16th week of intrauterine life – after formation of tooth buds
Involves only the permanent dentition
- Dentinogenesis imperfecta
DENTINOGENESIS IMPERFECTA = Dentinogenesis imperfecta(DI) is agenetic disorder (AD)oftooth development. This condition is a type of dentin dysplasia that causesteethto be discolored (most often a blue-gray or yellow-brown color) and translucent giving teeth an opalescent sheen.[1]Teeth are also weaker than normal, making them prone to rapid wear, breakage, and loss.
- Enamel caries: white plaque, cavitary lesion
Enamel 95% of hydroapatite – very hard tissue. Due to the action of proteolytic enzymes and cariogenic acids > succession of demineralization and remineralization phases. The enamel caries start below the bacterial plaque. Plaque… strep lactob…
Cavitary lesion due to a slow dissolution of the enamel, along the prisms and the interprismatic areas.
- Dentin caries
DENTIN CARIES:
Secondary to enamel caries (coronal caries) or cementum caries (cervical caries)
Evolves more rapidly
Large amount of organic substances in the dentin -30%
Dentin is injured
Initially by the bacterial cariogenic acids
Different bacterial species than the ones for enamel:
Role of anaerobes (lactobacilli) is more important
Later, bacteria penetrate the dentinal tubules
As a result, the organic component is demineralized and then liquefied
Dentin caries are cone shaped, with the tip pointing towards the pulp chamber
LAYERS:
NECROTIC (surface)
INFECTED / AFFECTED
SCLEROTIC (DEEP)
- Internal and external resorbtion
RESORBTION= Loss of dental tough subtance on the surfaces which are not exposed to the outside.
In contact with the pulp region (crown, roots)
In contact with the periodontal ligament (roots)
INTERNAL RESORBTION: Rare Causes: Pulp traumas Pulpitis secondary to caries Pulpotomy Starts in the pulp and evolves towards the surface of the cementum or the crown => until it produces a communication between the pulp and the periodontal space or the external surface of the crown
EXTERNAL RESORBTION:
Much more frequent
Starts at the surface of the tooth, in contact with the periodontal ligament
- Acute reversible and irreversible pulpitis
REVERSIBLE PULPITIS (PULP HYPEREMIA): Reversible pulpitis is generally characterized by sharp sensitivity to cold, sometimes to sweets and sometimes to biting.
The initial stage of pulp inflammation
Closed
Partial – the tissue zone is expanded only a little
Aseptic
Acute
Causes:
Deep, but closed caries
Large, incorrect metallic obturations
Evolution:
Healing after the disappearance of irritant factors
Towards a total acute pulpitis if the agression persists
ACUTE IRREVERSIBLE PULPITIS: Irreversible pulpitis is generally characterized by prolonged sensitivity to cold and/or heat, and sometimes to sweets. Swelling may be present.
Etiopathogenesis:
Exacerbation of a reversible pulpitis by opening the pulp chamber
- Chronic pulpitis and the pulp polyp
CHRONIC PULPITIS:
Can appear directly, spontaneously
After an acute pulpitis, when the pus is drained through the carious orifice
CHRONIC HYPERPLASTIC PULPITIS (PULP POLYP): Apulp polyp, also called as Chronic Hyperplastic Pulpitis, is found in an opencarious lesion, fracturedtoothor when adental restorationis missing. Due to lack of intrapulpal pressure in an open lesionpulpnecrosisdoes not take place as would have occurred in a closed caries case.
- Periapical granuloma
PERIAPICAL GRANULOMA
(CHRONIC APICAL PERIODONTITIS) = Aperiapical granulomais a mass of chronically inflamedgranulation tissuethat forms at the apex of the rootof anonvital(dead) tooth. However, a periapical granuloma does not containgranulomatous inflammation, and therefore is not a truegranuloma.
Etiology:
Apical defense reaction to the presence of bacteria and their toxins in the root canal
- Apical periodontal (radicular) cyst
APICAL PERIODONTAL CYST = APICAL RADICULAR CYST = Theperiapical cyst(also termedradicular cyst, and to a lesser extentdental cyst) is the most commonodontogeniccyst. It is caused bypulpalnecrosissecondary todental cariesortrauma. The cyst lining is derived from thecell rests of Malassez. Usually, the periapical cyst is asymptomatic, but a secondaryinfectioncan causepain.
- Periapical abscess
PERIAPICAL ABSCESS (ACUTE PERIAPICAL PERIODONTITIS) = collection of pus usually caused by an infection that has spread from a tooth to the surrounding tissues.
Well delimited purulent inflammation located at the apex of a tooth
EVOLUTION:
DRAINAGE OF PUS TOWARDS THE GINGIVA:
FISTULIZATION→ the symptoms disappear
- Acute gingivitis, acute ulcero-necrotic gingivitis
ACUTE GINGIVITIS = Initial form of a periodontopathy The acute nature is established by the intensity of the local irritation: Sulcular plaque The patient’s immune resistance
ACUTE ULCERATIVE NECROTIC GINGIVITIS (AUNG)= Acute necrotizing ulcerative gingivitis is a common, non-contagious infection of the gums with sudden onset. The main features are painful, bleeding gums, and ulceration of inter-dental papillae. In the early stages some patients may complain of a feeling of tightness around the teeth. Three signs/symptoms must be present to diagnose this condition: Severe gingival pain, Profuse gingival bleeding that requires little or no provocation, Interdental papillae areulceratedwithnecroticslough
- Chronic gingivitis
HRONIC GINGIVITIS = gingivitis is a non destructive periodontal disease.
An inflammatory process of reduced intensity, without symptoms
Elderly people
Causes:
A. From the start
Defective hygiene – chronic accumulation of bacterial plaque
Mechanical and chemical irritation
B. Evolution of an acute gingivitis
C. Down syndrome, diabetes mellitus, increased progesterone levels (pregnancy)
- Drug induced gingival hyperplasia and gingival fibromatosis
DRUG RELATED GINGIVAL HYPERPLASIA = Drug-related gingival hyperplasiais a cutaneous condition characterized by enlargement of the gums noted during the first year of drug treatment.[1]There are three drug classes that are associated with this condition namely, anticonvulsants (such as phenyotoin and phenobartibal), calcium channel blocker( such as amlopidine, nifedipine and verapamil) and cyclosporine, an immunosuppressant.
Hereditary gingival fibromatosis (HGF), also known as idiopathic gingival hyperplasia, is a rare condition of gingival overgrowth.[1] HGF is characterized as a benign, slowly progressive, nonhemorrhagic, fibrous enlargement of keratinized gingiva. It can cover teeth in various degrees, and can lead to aesthetic disfigurement.[2] Fibrous enlargement is most common in areas of maxillary and mandibular tissues of both arches in the mouth.
- Adult chronic periodontitis
ADULT CHRONIC PERIODONTITIS = Chronic periodontitisis a commondiseaseof theoral cavityconsisting ofchronicinflammationof theperiodontal tissuesthat is caused by accumulation of profuse amounts ofdental plaque. Redness + bleeding, gum swelling, halitosis, gingival recession, deep periodontal pockets, loose teeth.
The most frequent cause of dental loss
