Now you will need only two things to master DAO:
1)The decks....I have been refering the 2001 version.So that will be good enough.
2)The ASDA reprints......the ones I have are till 1996
So lets start with the topic about which I did not know ANYTHING till I started studing for my boards.And I used to go crazy trying to figure them out.
Mandibular Movements
Now basically there are only 2 movements....
A)The Functional Mandibular Lateral Excursion.
B)Mandibular Protrusion.
But since the mandible is a bilateral joint,there are two sides to consider in the lateral movement.
1)the working side:this is the side to which the mandible is moving.
2)Non-working side:The other side.....thats the side from which the mandible is moving away from.
How do you determine which is the working side and the non-working side looking at the arrows on the text?
SIMPLE!
When the arrow is exactly horizontal......pointing towards the lingual on mandibular and buccal on the maxillary teeth it is a WORKING SIDE MOVEMENT!
Now I am sure all of you will be able to determine the side looking at the occlusal surfaces of the teeth shown.
So when there is a Horizontal arrow that is a working side movement of the same side.
1)Imagine a diagram showing the occlusal surfaces of the lower right posteriors.The arrow is exactly straight pointing towards the lingual,then the movement is a working side movement to the right side.
2)When the occlusal surfaces of the upper left posteriors is shown with the arrows pointing to the buccal, its a working side movement to the left.
As simple as that!
Now in case of the non-working side movements,the arrow is obliquely directed.
The Mandibular cusps move mesially and lingually and the Maxillary teeth move distally and facially.
So if u have the occlusal surfaces of the lower right posteriors with the arrow pointing distofacially its a non-working side movement to the right(see 1 above)
and similarly if you have the occlusal surfaces of the upper right posteriors with the arrow pointing to the mesiolingually its the non-working side movement to the left....see 2 above!
Remember the arrows do not depict the movement of the cusps shown.They indicate the direction the occluding cusps move in the respective movement
so in 1 even though u have the lower right teeth shown with the arrow pointing to the lingual, it does not mean that the lower teeth are moving lingually.It means that the occluding teeth, viz. the upper right teeth are moving lingually against the lower teeth.
The protrisive movement is very easy to understand, as there is no working and non-working side confusion here.
just remember the direction of the arrow on the respective teeth.....it will point anteriorly on the maxillary and posteriorly on the mandibular teeth.
VERY ZIMBLE.......as my mallu geography teacher would have said it.
so now I would like you all to get out your reprints first, read only the questions with the occlusal surfaces of teeth and arrows on them.....and try to solve them using this key which I have given.You all have to get them right.
a very simple way to do it is to make a chart in the following format
Direction of arrow on the working side as shown on following teeth:
1)maxillary 2)Mandibular
buccally lingually
and draw diagrams showing the movement and direction of movement of cusps.
do the same thing for the non working side....and put it up on the mirror......you will surely master this aspect within a week,unless you are bald....in which case you have to put it somewhere u will see it the most......
There is a lateral-protrusive movement, but I think there is only one question showing this movement so I will not include this here as it is very confusing and not too important.
hope I have not bored you all with this.
Please let me know what you feel about my tutorial, whether it has helped you in any way and whether you would like me to make any changes in the next one....
happy mandibular movements!
