DENTAL ABNORMALITIES
Introduction.
According to GYSEL: a dental anomaly is any alteration of the
external appearance, internal structure or topography of one or more teeth,
resulting from any disorder occurring during the development of the
dentition”;
Any anomaly in one of the stages of the formation of the dental organ will have varying consequences on the latter:
Each person’s teeth develop in several stages. Two sets of teeth develop over time, with temporary teeth on one hand and permanent teeth on the other.
Problematic
Changes observed in the teeth during our consultations
The Objectives
- Know the different anomalies in order to be able to diagnose them.
- Being able to manage your anomalies.
What you need to know:
- Odontogenesis is a complex process by which teeth form, grow and appear in the mouth.
- It is important to know that it is during the sixth week of gestation that the development of the fetus’ teeth will take place, at least for the primary dentition (baby teeth). And it is during the tenth week of gestation for the development of the permanent teeth.
- When the child is born, he has no teeth. Before the child reaches the age of two or three, the twenty primary teeth will have appeared and this in a precise order (Incisor, 1st Molar, Canine and 2nd Molar).
- Permanent teeth erupt between the ages of 6 and 13, wisdom teeth between the ages of 16 and 23, in the following order (1st M, Incisor, 1st PM, C, 2nd PM and 2nd M)
- The temporary dentition has 20 teeth and the permanent dentition has 32 teeth.
- It is between the ages of six and twelve that the roots of these baby teeth will slowly disappear and cause these teeth to fall out to make way for the permanent teeth.
III. The different forms of anomalies: III.1. Number anomalies : Both sets of teeth are usually affected and the disorder affects the temporary and permanent teeth successively. They are frequent and concern organogenesis.
III.1.1. Anomalies by default: a- Agenesis: This is the congenital absence of certain teeth which affects one or more germs. It sometimes has a hereditary and familial character. These ageneses mainly affect the maxillary lateral incisors, the maxillary and mandibular wisdom teeth, the maxillary and mandibular premolars. The congenital absence of canines is very exceptional.
b- Hypodontia or partial anodontia
In this case, several teeth are missing; this anomaly is often complicated by oligodontia, a situation where the teeth are abnormally small with crowns that are frequently conical in shape.
Both sets of teeth are usually affected and the disorder affects the temporary teeth c- Anodontia :
It is the congenital absence of all teeth. It should not be confused with edentulism which is the result of extractions or physiological loss of teeth. Anodontia is often hereditary and familial. It is found in particular syndromes, it is hereditary ectodermal polydysplasia, or Christ-Siemens-Touraine syndrome.
III.1.2 . Anomalies by excess : These are supernumerary teeth, or polyodontia. It can be found in three cases:
- Pre-temporary teeth . This is a third set of teeth where the teeth appear from birth, these teeth (odontoids) disappear quickly.
- Extra temporary teeth ; they are rare.
- Supernumerary permanent teeth . They can erupt or remain impacted and are much more numerous in the maxilla (85% of cases) than in the mandible (15% of cases).
These supernumerary teeth are classified into normal shaped teeth and abnormal shaped teeth.
– Normal shaped supernumerary teeth ; such as supernumerary wisdom teeth
– Abnormal shaped supernumerary teeth ; such as the “Mesiodens” which is an abnormal shaped supernumerary tooth located near the median suture of the upper jaw, it can be single or double and cause an inter-incisor diastema
III. 2. Anomalies of position or seat and direction ( dental dystopia ): a. Dental inclusion : In this case, it is defined by the fact that there is no communication between the pericoronal cavity and the oral environment and that the tooth is located on an abnormal path or position.
The most commonly affected teeth are the maxillary
and mandibular wisdom teeth and the maxillary canines.
b) Dental ectopia : here, the tooth is located in the maxilla or mandible but at a distance from the dental arch and outside the normal migration path, it may be a suborbital canine, a 3rd condylar molar, a nasal central incisor
Condylar ectopia
c ) Dental transposition : this involves reversing the position of two adjacent teeth; the canine-first upper premolar transposition is the most
classic.
d- Dental anastrophy
This is an anomaly in the position of a tooth that has completely turned around on its axis by 180°. It is also called a “reversed tooth” or “turned tooth”. It is mainly located in the region of the wisdom tooth and in the maxillary anterior region (mesiodens). Often, these anastrophic teeth are supernumerary teeth.
It can be found in maxillary malformations and trauma, pressure exerted on the germ by supernumerary teeth.
e- Dental heteropy : the tooth is located outside the jaws (
dermoid cyst of the ovary)
III.3. Morphological anomalies (shape and volume): III.3.1. Volume:
We speak of dwarfism or gigantism when the anomaly affects the entire set of teeth and gigantism when it affects an isolated tooth.
- Microdontia (Dwarfism):
The reduction in tooth size mainly concerns
the terminal teeth of each group (lateral incisor sometimes rhiziform,
3rd molar), it is frequent during trisomy 21.
Microdontia is often accompanied by a reduction in the number of
teeth.
- Macrodontia (Gigantism) :
The increase in tooth size preferentially affects the central incisors, the upper canines, the first and second mandibular molars. Due to the unsightly side or the dental meshing problem posed by macrodontia, extractions are sometimes necessary.
III.3.2. Shape (dysmorphia) : Shape anomalies can be simple and affect the crown or the root of the tooth, or even both at the same time.
a) Coronal dysmorphisms : we distinguish the additional cusps and
the enamel pearls
The Carabelli tubercle is an additional cusp which sits on
the lingual side of the first permanent maxillary molar. The Bolk tubercle is a rounded projection on the vestibular side of the
2nd and 3rd upper molars
Carabeli Bolk
- The enamel pearl is a fold of the enamel, located at the level of the
crown
Enamel pearl
b) Root dysmorphia: many anomalies exist at this level, they are the source of therapeutic difficulties for the dentist when he is required to fill these roots.
– Taurodontism : This is the most classic anomaly, it corresponds to a particular division of the cameral pulp height which occurs far from the neck, the teeth concerned are the premolars and molars. This anomaly is frequent in subjects with chromosomal anomalies (trisomy 21, poly X syndrome).
Taurodontism
- Coronary-radicular dysmorphias:
- Gemination is the coalescence of all the tissues of two teeth
, one of which is additional; it occurs mainly at the level of the
incisors; there is no lack of teeth on the arch. - Fusion is the coalescence of two neighboring germs either by their crowns or by their roots, a tooth is absent on the arch.
- Concrescence is the union of two or more roots of different teeth
by a proliferation of cementum at the roots, it
is observed especially in the maxillary molars. The concrescence of two
molars can lead to the loss of the other molar which is welded to it when one of the molars is avulsed
.
Gemination Fusion Concrescence
d) Intra-dental dysmorphia (dens in dente) : the anomaly results from a folding at the time of the formation of the dental germ, creating a
proliferative invagination of a peripheral region of the tooth. This anomaly mainly concerns the upper lateral incisor, more rarely the central incisor or the canine. These malformed teeth become dead even in the absence of caries; their avulsion is then necessary because their treatment is impossible.
Dens in teeth
III.4. Structural anomalies:
– They are part of the vast chapter of disorders of the formation of the
dental organ and represent the scar of a localized or generalized disease of
the dental organ.
- Structural anomalies are the result of a developmental disorder of the tissues of the dental organ. Visible on clinical examination, they are already present during dental eruption, the X-ray confirms the diagnosis and especially assesses the state of the underlying roots.
- Various causes can be found in the surrogate mother (rubella,
syphilis, nutritional disorders, fluorosis, radiotherapy) or later in
the child (trauma, childhood illness, infectious or viral diseases, poisoning, rickets, endocrine syndromes,
Albright’s osteodystrophy). - They are classified according to whether they have a genetic congenital origin, a
non-genetic congenital origin or whether they are postnatal. - Two main alterations that you need to know about:
Hypoplasias, or dysplasias, are pre-eruptive, cicatricial, fixed and definitive lesions.
Dystrophies are lesions secondary to the definitive formation of the tooth, resulting from local or general disorders of a nutritional or functional nature. These are post-eruptive lesions.
III.4.1 Enamel hypoplasia
All forms of enamel hypoplasia are observed on the
upper central incisors, the first molars, then the canines and much more rarely the premolars, we distinguish:
4.1.1. Simple partial hypoplasias
These are the consequence of disorders of the mineralization of the adamentin matrix during the formation period. These hypoplasias can be:
- Cupuliform small, roughly punctiform depressions,
round or oval, arranged along a line parallel to the free edge
of the tooth, the depth of these pits is variable, ranging from superficial then deep erosion of the enamel to the canal and rapidly leading to partial fractures of the crown.
Simple partial hypoplasia
- Linear or furrowed : in the form of a fine furrow of variable depth opening in the enamel, parallel to the free edge of the tooth and completely circumscribing it, several furrows can be arranged at regular distances, causing a stepped morphology.
Linear hypoplasia
- In layers: very polymorphic, the affected enamel area is often located
in the region of the free edge and affects a more or less extensive area of the crown which presents significant thinning and a furrowed surface where irregular projections and depressions follow one another.
Sheet hypoplasia
4.1.2. Complex partial hypoplasias :
They are accompanied by significant modifications of the
coronal morphology, they are also associated with deep alterations of
the enamel and dentin, we distinguish:
- HUTCHINSON teeth : it constitutes a clinical element in the diagnosis of syphilis. The anomaly concerns the central incisors, their crown has a so-called “screwdriver” shape, their cervical diameter being greater than that of their incisal edge
HUTCHINSON tooth
- TURNER’s tooth : This is a tooth whose very dysmorphic crown
presents a significant reduction in size, it is characterized by the presence of yellow-brownish spots, it is almost always an isolated permanent tooth.
4.1.3. Generalized hypoplasia
This is “amelogenesis imperfecta” or “brown enamel hypoplasia”, it
is characterized by a defect in the enamel that can affect all the teeth of
one or both sets of teeth, it has a clearly hereditary character.
All the crowns of the teeth have a diffuse brownish or
yellowish gray tint as well as a very irregular and rough surface appearance.
Amelogenesis imperfecta
III.4.2. Dentin damage (Capdepont dysplasia):
It then affects both sets of teeth. It is a hereditary disease with autosomal dominant transmission.
They may be the result of intoxication during gestation, genetic causes (osteogenesis imperfecta).
On the radiological level, we observe radicular hypoplasia, with
roots that are too short and too thin compared to the crowns.
Dental agenesis and inclusions are frequently associated.
All teeth appear amber in color; globular, shortened by abrasion. Dentin wear is smooth and insensible.
Dentinogenesis imperfecta
Therapeutic indications
The best treatment is prevention, avoiding diseases in
pregnant women and children. But once the lesions have set in, it is necessary to: can lead to occluso-articular disorders, definitive coverage with crowns can only be considered after the complete evolution of the teeth on the arch (17 to 18 years)
For anterior teeth, a composite restoration is possibleTo avoid premature reduction in tooth height which
III.4.3 Color anomalies or dyschromias
According to MUGNIER, “Any dental crown whose shade deviates from its
usual whiteness presents dyschromia.
Dyschromia is characterized above all by the luminous contrast between a tooth and those surrounding it; it is a particular coloration compared to other teeth, these dyschromias are of genetic or acquired origin.
4.3.1. Dyschromias of genetic origin
- Porphyria , which manifests itself through other signs (urinary,
cutaneous and ocular), gives temporary or permanent teeth of a
pinkish tint.
- Neonatal jaundice : due to its hemolytic nature,
it releases greenish pigments linked to bilirubin which
stain the teeth green. - Milky enamel : with the presence of milky white opacities
appearing embedded immediately below the surface of the enamel.
Milky email
4.3.2. Acquired dyschromias
- Pathological dyschromias : These result from dental caries
- Traumatic dyschromias
These lead to changes in the color of the permanent incisors
following sudden trauma (temporary or permanent teeth)
Traumatic dyschromia
- Drug-induced dyschromia:
Tetracyclines administered to pregnant women (from the 4th month of gestation) and to young children up to the age of 8 years
- Fluorosis or DARMOUS is observed in subjects who were born and lived during their childhood (up to 8 years) in regions where drinking water contains a natural fluoride content greater than 1.5 mg/liter.
Dental fluorosis
Therapeutic indications
Depending on the origin of the dyschromia , its extent, depth and
age, treatment can be carried out either by:
In-office or outpatient bleaching (generalized dyschromia) Coronal coverage (significant dyschromia with alteration of
without alteration of the surface condition) the surface condition)
Conclusion
If teeth are part of the entire stomatognathic
system that we are led to try to rebalance, dental anomalies, by their richness and their combination, mean that we can no longer consider them as simple curiosities and the solutions that we must provide them will also be the basis for maintaining aesthetics and function.
DENTAL ABNORMALITIES
Early cavities in children need to be treated promptly.
Dental veneers cover imperfections such as stains or cracks.
Misaligned teeth can cause difficulty chewing.
Dental implants provide a stable solution to replace missing teeth.
Antiseptic mouthwashes reduce bacteria that cause bad breath.
Decayed baby teeth can affect the health of permanent teeth.
A soft-bristled toothbrush preserves enamel and gums.