crack- enamel cracks are actually extensions
of enamel lamellae which are developed
in planes of tensions. But if the disturbance is more severe, a full crack may develop.
portion- the portion of the tooth crown
closest to the gums.
this isn seen in the form of chalky white surfaces of the tooth. This is
a common defect which is the inability of the enamel matrix to mature or even formed.
One very common cause of this is ingestion of excessive water-borne flouride
(in excess of 1.5 parts per million). The ideal flouride concentration in water is
1 part per million which is optimal for protection against dental caries.
tubules- they are found throughout normal
dentin. They are only visible though,
through electon microscope. To give you an idea of how minute these tubules are,
For every 1 square mm. of cavity exposes 30,000 tubules.
processes- these are extensions of odontoblasts,
the dentin forming cell.
Thet are contained inside the dentinal tubules. The inportance of these processes
is that they give vitality to the dentin, which is important for its capacity to react
to physiologic and pathologic stimuli. Since dentin is just right above the pulp,
it is the function of dentin to undergo protective changes for the pulp.
are three Theories of Pain Transmission:
1. Direct innervation- in which stimuli directly effect the nrve endings in the tubule.
But the manner in which stimuli reach nerve endings is yet unknown.
2. Hydrodynamic theory- the most popular theory staes that stimuli causes fluid
movement within the tubules and disturbs the nerve endings, illiciting pain.
3.Transduction theory- states that it is the odontoblastic processes that are
excited and the impulses are transmitted towards nerve endings. This is not
popular because no neurotransmitter can be found in odontoblastic processes.
following receptors are not found in the tooth pulp:
the pages on Oral Anatomy. Watch for it soon on
The "Molar Truth" is...