PATHOLOGY OF THE TOOTH AND PERIDENTAL TISSUES
- INTRODUCTION
- Goals
II) DENTAL DYSGENESIS AND DYSPLASIA
– Tooth size abnormalities
– Shape anomalies
– Number anomalies
-Dental eruption disorders
-Disorders of the structure of the teeth
– Tooth discoloration disorders
III) CARIES
– General
– Seat of caries
– Anatomy pathology of caries
IV) DISEASES OF THE PULP AND PERIAPICAL TISSUES
V) DISEASES OF THE PERIODONTAL AND GUM
– Inflammations and dystrophies
– Cementum pathology
VI) CONCLUSION
- INTRODUCTION
Periodontal diseases are one of the main pathologies leading to oral treatments. They account for 30 to 40% of the causes of tooth extraction, while 50 to 60% of avulsions are due to the consequences of caries.
Goals
- Know the anomalies of the tooth
- Place of anatomy pathology in the pathology of caries and periodontium.
II) DENTAL DYSGENESIS AND DYSPLASIA
Dental anomalies have polymorphic aspects, some are due to a genotypic aberration of the odontogenic organ or to a direct lesion of it. The others are acquired during intrauterine life or after birth.
1-) Tooth size abnormalities
Tooth size is genetically determined and varies from person to person.
Only extreme variations in size are pathological:
Macrodontia : increase in the volume of a tooth, is exceptionally diffuse (pituitary gigantism).
Microdontia : reduction in the volume of a tooth, is rarely generalized.
2-) Shape anomalies
- Crown shape variations: due to supernumerary tubercles.
- Variations in the shape and number of roots:
-curved roots
-dental lacerations consist of an angulation between crown and roots
– bifid or supernumerary roots.
-concrescent roots are due to the union of the roots of two neighboring teeth by cement after resorption of the alveolar bone.
3-)Number anomaly
Reduction in the number of teeth (anodontia, hypo or oligodontia), caused by atrophy or absence of one or more dental buds and must be differentiated from impacted teeth.
Increase in the number of teeth (supernumerary teeth or hyperodontia), linked to the presence of supernumerary dental buds or the splitting of a bud into two.
4-) Tooth eruption disorder
- Premature eruption of unknown cause
- Delayed eruption of unknown etiology
- Single impacted tooth
- Multiple impacted teeth
5-) Tooth structure disorder
* Dentinogenesis imperfecta (hereditary opalescent dentin): often associated with Lobstein’s disease (osteogenesis imperfecta) is due to a genetic inability of odontoblasts to build normal collagen fibers in the dentin matrix.
The teeth are brown with soft dentin that wears away and fractures easily.
* Amelogenesis imperfecta (hereditary enamel dysplasia) is divided into 3 types depending on the mechanism of the defect in question:
-hypoplasia, or the organic matrix secreted by the ameloblasts is defective.
-hypomineralization
-hypo-maturation
* Acquired enamel hypoplasia.
6-) Tooth discoloration disorder
Taking tetracycline, this antibiotic is incorporated into the tissues in the process of mineralization, if it is administered during the period of development of the tooth bud, the tooth presents a brown pigmentation.
- Melanodontia: temporary black discoloration of the tooth of unknown etiology.
- Green tooth observed in biliary atresia.
- Erythrodontia in congenital porphyria with red fluorescence.
III) CARIES
1-) Generalities
Definition : chronic bacterial disease that destroys the hard tissues of the tooth, which are demineralized and dissolved by organic acids that come from the fermentation of carbohydrates under the influence of bacteria.
Factors of cariogenesis : multiple factors have been invoked:
– foods (harmful role of carbohydrates)
– dental plaque formed from microorganisms and organic substances at acid pH and fixed on a film of dehydrated salivary mucins normally adhering to the enamel.
2-) Location of caries:
– crown caries, the most common.
– cervical caries is the prerogative of elderly subjects as well as patients irradiated for cancer of the cervico-facial region.
– cementum caries specific to the elderly is the result of dental loosening (periodontitis)
3-) Pathological anatomy of caries
3.1-) Enamel caries : it has a different appearance depending on its location:
– interproximal caries: developed below the point of contact with the neighboring tooth, is triangular and excavates secondarily after caries of the underlying dentin.
– caries of the occlusal surface: begins at the bottom or on the edges of the anatomical fissures.
Histologically, a slightly demineralized superficial zone and an almost completely demineralized body can be distinguished.
3.2-) Dentin caries
First excavated in a cup, it takes the form of a cone with the apex directed towards the pulp.
Histologically, from depth to surface, we describe: degeneration of odontoblasts, dentin sclerosis due to progressive obliteration of the tubules by mineralized deposits, dentin demineralization, bacterial invasion of demineralized dentin and dentin necrosis.
3.3 Cementum caries
Superficial softening occurs, followed by a cup forming towards the dentin.
IV) DISEASES OF THE PULP AND PERIAPICAL TISSUES
1-) pulp calcifications:
They are made up of either secondary dentin or calcified material.
2-) pulpitis: develops in an acute or chronic manner:
Acute pulpitis : secondary to caries, is characterized by the association of leukocyte hyperemia and diapedesis which can lead to the formation of one or more abscesses.
Chronic pulpitis : secondary to the previous ones or occurring immediately, comprising an inflammatory granuloma embedded in collagen sclerosis.
3-) periapical inflammation: any pulpitis can be a source of complications, the most common is periapical granuloma, this is revealed by pain when pressing on the tooth with a clear image of osteolysis on X-ray in the alveolar bone.
Histologically shows a granuloma where lymphocytes, plasma cells and macrophages predominate with cholesterol crystals, on the periphery there is a fibrous shell. The evolution is towards the apico-dental cyst.
4-) periapical abscess: complicates an untreated granuloma, in the absence of early excision, it leads to various complications (phlegmon and osteomyelitis).
5-) Complications of periapical lesions
– Chronic sinusitis in case of periapical involvement of the upper teeth.
– Pelvic-buccal phlegmon for the lower teeth.
– Thrombophlebitis of the facial veins which may extend towards the cavernous sinus.
– Triggering of various remote conditions (endocarditis, arthritis, kidney conditions and others).
V) DISEASES OF THE PERIODONTAL AND GUM
1-) Inflammations and dystrophies of the gums and periodontium:
Periodontal disease (gum, periodontal ligament, cementum and alveolar bone).
– etiological factors:
Local factors : bacterial dental plaque is the essential element, it calcifies and transforms into tartar.
General , endocrine, nutritional (hypovitaminosis C), hematological factors.
1.1-) chronic gingivitis: frequent and almost constant in the elderly, the gum is hyperplastic.
Histologically, epithelial hyperplasia and an inflammatory infiltrate of the chorion are observed ; it can develop into periodontitis.
1.2-) periodontitis: it is an inflammation, sometimes suppurative, of a periodontal pocket, characterized histologically by a major inflammation of the periodontal ligament with resorption of the alveolar bone, it can be complicated by a periodontal abscess.
1.3-) periodontosis or diffuse alveolar atrophy: rare condition of unknown etiology.
2-) pathology of the cementum
2.1-) Hypercementosis : it can be total (encompassing the entire dental root), or partial (affecting only the apex).
– Total hypercementosis is physiological in the elderly
– Partial hypercementosis is reactive to apical dental inflammation, devitalization or repair of dental fracture.
2.2-) other modifications of the cementum:
– cementides: calcification of epithelial remains.
– cementolysis: resorption of cementum by cementoblasts, following dental trauma (fracture).
– ankylosis is linked to an absence of ligament between cementum and alveolar bone.
VI) CONCLUSION:
Prevention through good oral hygiene remains the best way to avoid heavy treatment for periodontal disease.
Bibliographic references
- Romieu G, Bertrand C, Panayotov I, Romieu O, Levallois B. How to handle an endodontic emergency. Actual Odonto-Stomatol. Sep 2012;(259):231‑44
- Bercy P, Tenenbaum H. Periodontology: from diagnosis to practice. De Boek Supérieur. 2017; 290
- Scully C, Rosenberg M. Halitosis. Dent Update. May 2003;30(4):205‑10
- https://eurekasante.vidal.fr/maladies/bouche-dents/gingivite-saignement gingivesparodontite.htm
- Voellinger Q. Oral Hygiene Manual. 2017.
PATHOLOGY OF THE TOOTH AND PERIDENTAL TISSUES
Wisdom teeth can cause infections if not removed.
Dental crowns restore the function and appearance of damaged teeth.
Swollen gums are often a sign of periodontal disease.
Orthodontic treatments can be performed at any age.
Composite fillings are discreet and durable.
Composite fillings are discreet and durable.
Interdental brushes effectively clean tight spaces.
Visiting the dentist every six months prevents dental problems.