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explanation needed pleeease

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simkarl

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1-leasion on one side in spinal cord causes ipsilateral motor loss and contralateral pain and temperature loss ( I know both have decussation to the other side of spinal cord)????? explain please..

2- an old question still no answer ? .
which describes the proper axial inclination of palatal root of maxillary 2nd molar--1.vertical
2.mesial and lingual
3.mesial and facial
4.distal and facial
5.distal and lingual.

thanks so much
 

Streetwolf

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#1 They decussate at different points. Pain and temperature decussate at the spinal cord level they enter into. If for instance you have a pain/temp nerve fiber entering at T6 from the left side, it will be traveling up the body at T5, T4, T3, etc on the right side. If you sever the spinal cord at T5 on the right side where this nerve is located at that point, you'll lose your left side pain/temp perception at T6 (and the rest of the levels below).

Motor loss is ipsilateral. I think descussation occurs in the cerebellum or at least near there, so any nerves in the left side of the spinal cord are going to the left side of the body (and the same for the right).
 

simkarl

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#1 They decussate at different points. Pain and temperature decussate at the spinal cord level they enter into. If for instance you have a pain/temp nerve fiber entering at T6 from the left side, it will be traveling up the body at T5, T4, T3, etc on the right side. If you sever the spinal cord at T5 on the right side where this nerve is located at that point, you'll lose your left side pain/temp perception at T6 (and the rest of the levels below).

Motor loss is ipsilateral. I think descussation occurs in the cerebellum or at least near there, so any nerves in the left side of the spinal cord are going to the left side of the body (and the same for the right).


Thanks :thumbup: a lot a great explanation and now I got the point and relation between lesion and the side affected,,
 

drmanglore

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i think for the 2nd ques: palatal root of max 2nd molar: inclines distally and palatally
 

I'mFillingFine

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i think for the 2nd ques: palatal root of max 2nd molar: inclines distally and palatally

agreed. The ONLY maxillary root that inclines BUCCALY is the DB of the first molar. All others are palatal (and distal, especially as you move more distally in the arch.)
 
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