Changes

===Enamel Dysplasia===

===Enamel Dysplasia===

'''Enamel dysplasia''' results from abnormal enamel formation on the crown of the tooth. This occurs when an injury or other disruption occurs during the [[Tooth Development|formation of enamel]]. All enamel formation occurs prior to [[Tooth Eruption|eruption of the tooth]]. The crown formation of the permanent/secondary teeth occurs from the second week postpartum to the age of three months. The crown of the first permanent mandibular molar, however, begins to undergo development and mineralisation prior to birth. Only those areas of the crown undergoing active formation at the time of the injury will be affected, giving the banded appearance sometimes seen. <font color="red">(pic11generalisedED)</font color> If only a small area of dysplasia is seen this is usually asscociated with localized trauma to the developing crown.  <font color="red">(pic12localisedED)</font color> <br>

'''Enamel dysplasia''' results from abnormal enamel formation on the crown of the tooth. This occurs when an injury or other disruption occurs during the [[Tooth Development|formation of enamel]]. All enamel formation occurs prior to [[Tooth Eruption|eruption of the tooth]]. The crown formation of the permanent/secondary teeth occurs from the second week postpartum to the age of three months. The crown of the first permanent mandibular molar, however, begins to undergo development and mineralisation prior to birth. Only those areas of the crown undergoing active formation at the time of the injury will be affected, giving the banded appearance sometimes seen. <font color="red">(pic11generalisedED)</font color> If only a small area of dysplasia is seen this is usually asscociated with localized trauma to the developing crown.  <font color="red">(pic12localisedED)</font color> <br>

Teeth with enamel dysplasia may appear completely normal at the time of eruption but, as soon as the animal begins to [[Mastication|use the teeth]], defective enamel flakes off and the remaining porous defective enamel and exposed dentine begins to discolour. It is important to remember that the insult to the developing tooth happened months before and not after full eruption.

Teeth with enamel dysplasia may appear completely normal at the time of eruption but, as soon as the animal begins to [[Mastication|use the teeth]], defective enamel flakes off and the remaining porous defective enamel and exposed dentine begins to discolour. It is important to remember that the insult to the developing tooth happened months before and not after full eruption.

====Clinical Significance====

====Clinical Significance====

Enamel forms the outer covering of the tooth and forms an impermeable barrier protecting the underlying tooth components. If enamel is poorly formed or missing completely the underlying dentine is exposed, resulting in sensitivity and severe pain in some cases. The sensitivity is caused by changes in the hydrostatic pressure in the dentinal tubules which contain odontoblast processes which trigger a pain pathway. In mild cases, the pulp will often respond to the stimulation by laying down more dentine, reparative (tertiary) dentine, which obliterates the dentinal tubule space. In severe cases of dysplasia, the pulp can become chronically inflamed and undergo irreversible pulpitis as a result of bacterial ingression through the exposed dentinal tubules; periapical disease then develops. <font color="red">Pic13-enamel dysplasiaRad</font color>  

Enamel forms the outer covering of the tooth and forms an impermeable barrier protecting the underlying tooth components. If enamel is poorly formed or missing completely the underlying dentine is exposed, resulting in sensitivity and severe pain in some cases. The sensitivity is caused by changes in the hydrostatic pressure in the dentinal tubules which contain odontoblast processes which trigger a pain pathway. In mild cases, the pulp will often respond to the stimulation by laying down more dentine, reparative (tertiary) dentine, which obliterates the dentinal tubule space. In severe cases of dysplasia, the pulp can become chronically inflamed and undergo irreversible pulpitis as a result of bacterial ingression through the exposed dentinal tubules; periapical disease then develops. <font color="red">Pic13-enamel dysplasiaRad</font color>

===Dens in Dente ===

===Dens in Dente ===