Malocclusion Flashcards
Any alteration in the bone growth of the maxilar, and/or mandible and in the dental positions that impede the correct function of the chewing system with the subsequent consequences that this dysfunction has on the teeth themselves the gums and the bones that support them the temporomandibular joint and facial aesthetics
Malocclusion
General factors
Hereditary
congenital defects
oral habits
tongue e trusting
thumb sucking
Lip chewing
Onicophagia
trauma and accidents
Local factors
Anomalies in the number of teeth
missing teeth: agenesis
Suprenumerary teeth
anomalies in tooth size
anomalies in dental shape
premature loss of deciduous teeth
Prolonged retention of deciduous teeth
cavities
inadequate dental restoration
Angle
Class 1
2
3
Angle class 1
Normal
When the mesiobuccal cuspid of the first permanent upper molar occludes in the bucal groove of the first permanent lower molar
Angle class 2
when the mesiobuccal cuspid of the first permanent upper molar occludes in front of the buccal groove of the first permanent lower molar
Angle class 3
Mesiobuccal cusp of the first permanent upper molar occludes behind the buccal groove of the first lower permanent molar
Is the anteroposterior relationship between the upper and lower permanent canines
Canine classification
Class 1 canine
The cusp of the upper canine occludes between the canine embrasure and the lower first premolar
Área occupied by the dental papilla
Tronera
Embrasure
Class 2 canine
the cusp of the upper canine occludes in front the embrasure of the canine and the lower first premolar
Class 3 canine
the cusp of the upper canine occludes behind the embrasure of the canine and the lower first premolar
What is more important to correct? Malocclusion in canines or molars?
Canines
Anomalies in the number of teeth
- agenesis
- hypodontia
- anodontia
- supernumerary teeth
- supplementary teeth
- conical teeth
- mesiodens
- hyperdontia
Agenesis
the absence of teeth can be seen in both arches
the absence is usually bilateral
agenesis is more common in permanent teeth
Two classifications of agenesis
Hypodontia
Anodontia
absence of formation of three or more DO
most common:
third molar
upper lateral incisors
second premolars
is one of the fundamental concerns of pediatric dentists and orthodontics due to the occlusal problems it generates causing functional and aesthetic problems over time
Hypodontia
disorder in which there are no temporary or permanent teeth because of the congenital absence of tooth germs
this alteration is classified according to the number of missing teeth and can be partial or total
Anodontia
Supernumerary teeth
a tooth that appears in addition to the regular number of teeth
they appear more frequently in the maxila
WHEN the affected region is located in the midline of the palate between the two upper central incisors it is called mesiodens
hereditary seems to play a more significant role in cases of missing teeth and also in supernumerary teeth
Tree types of supernumerary teeth
- supplementary teeth
- conical teeth
- mesiodens
it has normal morphology and size
in permanent teeth as extra upper lateral incisor or as lower incisor
always erupted
Supplementary teeth
Extra teeth presented as a conical crown and smaller root than a normal tooth
Conical teeth
Extra tooth located in the premaxilla near the midline between the upper central incisors
it can also appears between lower CI
Mesiodens
Hyperdontia
having more than the regular number of teeth
due to the hyperactivity of the dental lamina with the consequent formation of additional tooth germs
Anomalies in tooth size
is genetically determined
MEN tend to have more square dimensions and WOMEN show a greater reduction in Bucio-lingual size than in mesio-distal size
in relation to tooth size it is observed that MENs teeth are larger than WOMENs
- microdontia (true generalized, relative generalized, localized)
- macrodontia (true generalized, relative generalized, localized)
Teeth smaller than the limits of variation considered normal
Tree types
Microdontia
Tree types of microdontia
True generalized microdontia (tiburonsin)
Relative generalized microdontia
3-5 teeth
Localized microdontia
Most common
Usually: upper lateral incisors and third molars
1-2 teeth
teeth bigger that the limits of variation considered normal
Tree types
Macrodontia
Tree types of macrodontia
True generalized macrodontia
Relative generalized macrodontia
localized macrodontia
Type of macrodontia
That it is Very rare condition and has been observed in some cases of pituitary gigantism and hemifacial hypertrophy
True generalized macrodontia
Type of macrodontia
That It is the result of the bone-dental discrepancy where the size of the teeth is bigger related to the jaws.
Relative generalized macrodontia
Type of macrodontia
That It is not common and its etiology is unknown
*upper central incisors
normal tooth in all respects except is sized
localized macrodontia
Anomalies in dental shape
dental morphology is determined by genetics
alteration in the shape of the teeth can be present in any dental group
- fusion
- gemination
- dilaceration
- dens in dente (invagination)
union of two developing teeth into a single structure
may have two independent pulp canals
Fusión
from a single enamel organ two teeth form or attempt to form
normally there is only one pulp canal
Gemination
its an excessive root angulation and may be the result of a trauma in the deciduous dentition
Dilaceration
lingual invagination of the enamel and can occur in primary and permanent teeth
Dens in dente (invagination)
Espacio entre dientes
Trema
Espacio entre los centrales superiores
Diastema
Anomalies in dental eruption
Premature loss of deciduous teeth
Prolonged retention of deciduous teeth
Refers of the early loss of deciduous teeth that can compromise the natural maintenance of the perimeter or arch length and therefore the eruption of the substitute tooth
Premature loss of deciduous teeth
Deciduous teeth not only serve as dental organs for chewing but also as maintainers for the permanent teeth
They also keep the antagonist teeth in their correct occlusal level
the temporary dentition must be kept intact UNTIL THE MOMENT OF REPLACEMENT, THEY HELP TO MAINTAIN THE THAT THE PERMANENT TEETH WILL NEED TO ERUPT
Importance of temporary dentition
premature loss of primary teeth is a severe problem that causes in the future
Problems Like:
loss of dental balance
shortening of the arch length due to mesialization of the posterior tooth
extrusion of the opposing teeth
problems in the TMJ
early orthotic treatments
there are multiples causes of premature loss of primary teeth the most common are:
Diseases :: dental caries, periodontitis ,atypical root resorptions
Involuntary causes :: trauma observed in the crown or the root ( falls accident), affect the upper anterior teeth
Bad oral habits :: mobility and early tooth loss
Before removing any primary OD it is necessary to obtain a …
it is necessary to obtain a rx periapical
The presence and position of the permanent successor must be established as well as the state of the root formation of the primary tooth to be extracted
When does it started to be a case of prolonged retention of deciduous teeth
And when is the normal time
A delay of more than six months occurs we may be facing a case of prolonged retention of the primary tooth or delayed eruption
Normal: more or less than 6 months
Mechanical interferences like PROLONGED RETENTION OF DECIDUOUS TEETH can cause bad positions and this would lead a malocclusion
And …
ectopic eruption, lead to the deciduous to never reabsorb their roots
Agenesis: La falta de formación del permanente
Greater prevalence in __ __teeth to erupt late
Second primary molar
Canines
Why does the second primary molars, canines are most likely to erupt late
The common causes are:
agenesis, impaction of the permanent successor or dental
ankylosis, which is also common in the deciduous dentition preventing the normal exfoliation of the deciduous and the eruption of the permanent successor
**
The permanence of temporary teeth in the mouth and their lack of exfoliation (que se caigan los deciduous) may also be due to the agenesis of the permanent teeth in turn
Physical barriers that can delay eruption
bone crypts at the line of eruption of the permanent tooth, supernumerary teeth that prevent the eruption
Also physical barriers can affect the direction of eruption and establish an abnormal eruption pathway.
PB like supernumerary, dec roots, bone barriers
union / fusion between a tooth and the alveolar bone.
This is due to a type of injury, which causes perforation of the periodontal ligament and the formation of a bone bridge joining the cement and the hard sheet.
we can dx this by a radiografía periapical, percusión, movilidad
Anquilosis
CAVITIES can be considered one of the many local factors that can cause a malocclusion
this can lead to:
premature loss of deciduous or permanent teeth
subsequent displacement of adjacent teeth
abnormal axial inclination
loss of arch length
Relashionship between cavities and maloclusions
Interproximal caries in the primary dentition represent one of the most causes of loss, the winged tooth migrates towards the cavity producing a shortening of the arch length and breaking the balance of the forces that keep the tooth in occlusion
Anomalies in dental structure
Imperfect amelogenesis
Imperfect dentogenesis
Dentin dysplasia
hereditary disorder of enamel formation affecting primary and permanent dentition
There are 3 types
Imperfect amelogenesis
3 types of imperfect amelogenesis
Hypoplasia
Hypocalcifies
Hypomaduration
Type of imperfect amelogenesis
Where the enamel does not have normal thickness in certain areas or in its entirety
Hypoplasia
Type of imperfect amelogenesis
Where the enamel has a normal thickness but is fragile and can be easily removed
Hypocalcifies
Type of imperfect amelogenesis
Where the thickness of the enamel is normal but it doesn’t have a normal hardness and transparency and opaque spots appear on the incisal edges of the teeth
Hypomaduration
It consists on opalescent teeth made up of irregularly formed and hypomineralized dentin that obliterates the coronal root and pulp chambers. The teeth range in color from bluish gray to yellowish.
The dentin is abnormally soft, despite to the exposure of dentin the teeth are not especially prone to dental caries.
Imperfect dentogenesis
It is an inherited disorder characterized by abnormal dentin formation and abnormal pulp morphology
Two types
Dentin dysplasia
Dentin dysplasia
Type I
Root dentin dysplasia
Dentin dysplasia
Type I - root dentin dysplasia
Teeth are affected in both dentitions. The teeth have a normal color and in some cases may present a bluish or brown transparency in the cervical region. The roots of the teeth are short, blunt, bulging, conical, or absent.
Dentin dysplasia
Type II
Coronal dentin dysplasia
Dentin dysplasia
Type II - coronal dentin dysplasia
Both the primary and permanent dentition are affected, however the appearance of the temporary teeth is different from the permanent teeth. Primary teeth clinically show a bluish gray, brown or yellowish color and have a translucent or opalescent appearance and the roots in both dentitions are normal.
