DEVELOPMENT OF TOOTH Topic : Five developmental disturbance of teeth affecting the size - PowerPoint Presentation

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DEVELOPMENT OF TOOTH

Topic : Five developmental disturbance of teeth affecting the size and number of teeth

Submitted by :

Nafeesath

shahana

mahazi

A.S

Developmental disturbance of teeth affecting the size of teeth

1.Macrodontia

Macrodontia

 is a condition in which any tooth or 

teeth

 appear larger than normal for that particular type of tooth. True

macrodontia

that involves the entire dentition is rare. It is more common that there is an enlargement of a single tooth due to a disturbance of 

morphodifferentiation

. It should not be confused with either 

taurodontism

 (bull teeth), fusion (double tooth) or the jaws being relatively small, giving the appearance of

macrodontia

. It is commonly associated with gigantism

macrodontia

2.Microdontia

Microdontia

 is a condition in which teeth appear smaller than normal. In the generalized form, all teeth are involved. In the localized form, only a few teeth are involved. The most common teeth affected are the upper lateral incisors and third molars. The affected teeth may be of normal or abnormal morphology.

There are 3 types of

microdontia

:

True generalized

microdontia

Relative generalized

microdontia

Microdontia

involving a single tooth

microdontia

Developmental disturbance of teeth affecting the number of teeth

3.Anodontia

In dentistry, 

anodontia

, also called 

anodontia

vera

, is a rare genetic disorder characterized by the congenital absence of all primary or 

permanent teeth.

It is associated with the group of skin and nerve syndromes called the ectodermal

dysplasias

.

Anodontia

is usually part of a syndrome and seldom occurs as an isolated entity.

Anodontia

 is the congenital absence of teeth and can occur in some or all teeth (partial

anodontia

or

hypodontia

), involve two dentitions or only teeth of the permanent dentition (Dorland's 1998). Many denominations are attributed to this anomaly: partial

anodontia

,

hypodontia

,

oligodontia

, the congenital absence,

anodontia

, bilateral aplasia.

Anodontia

being the term used in controlled vocabulary 

Medical Subject Headings

 (

MeSH

)

from MEDLINE

 which was developed by the United States National Library of Medicine. The

Anodontia

of at least one permanent tooth is the most common dental anomaly and may contribute to masticator dysfunction, speech impairment, aesthetic problems, and malocclusion (Shapiro and Farrington 1983). Absence of lateral incisors represents a major stereotype. Individuals with this condition are perceived as socially most aggressive compared with people without

anodontia

(Shaw 1981

)

Partial

anodontia

, known as 

hypodontia

 or

oligodontia

, is the congenital absence of one or more teeth. Congenital absence of all wisdom teeth, or third molars, is relatively common

.

4.Supernumerary teeth 

Supernumerary teeth

 are the extra teeth that one can have in the mouth. They can be found at any location in the oral cavity. This condition is referred to as

hyperdontia

.

The specific cause of the development of the extra teeth has not yet been established. But there are a number of theories that have been put across to explain their presence. Some theories say that these teeth might be present due to the division of the tooth bud in a way that is not normal while other theories blame the existence of the supernumerary teeth on the dental lamina hyperactivity. It is also believed that a person’s genetics has something to do with this condition because it is considered hereditary

.

5.Post permanent dentition

The

rare appearance of supernumerary teeth after loss of permanent teeth; most teeth that appear after extraction of permanent teeth are due to eruption of previously impacted teeth