The angulation of upper 1st permanent molars,
the key to functional occlusion
(G. Risse)
Centrepiece in Orthodontics / Dentistry
Are the upper first molars, the first erupting permanent teeth, angulated (inclinated) with their crowns too much mesially, all other later erupting teeth are forced to erupt too much mesially too, with wrong angulations, wrong function, too much protruded centrals, or missing space for canines and unnecessary extractions – Domino Effect. (G. Risse)
By this, the angulation of the upper first molars are the centrepiece of orthodontic diagnosis and treatment.
As an orientation:
The age adapted angulations of the upper first molars are:
At the age of 6 years about: -17°
At the age of 10 years about: -10°
At the age of 18 years (adult): - 5° (Text Book Anatomy)
Consequences
To treat especially young patients for straight wire angulations by + 5° degrees of the upper first molars (Common Orthodontics) means a difference of 15° degrees to – 10° degrees of a 10 – 11 years old patient.
By this the crowns of the 1st upper molars will get a rotational moment forward up to 5° degrees around the apex of the molars, as the apex of the upper first molars will be stationed by missing space distally and by the germs of the second upper molars of a young patient behind the apex of the 1st upper molars. (“row boat effect”).
Mesial rotated crowns of the upper first molars by 10°- 15° degrees mean a mesial postinoning of the first upper molars of about 5-7 mm each side.
This again means a severe crowding or missing space anteriorly of 5-7 mm,labial positioned canines, protruded upper front teeth, beside a mesial malpositioning of the upper teeth in relation to the lower teeth, (Domino effect). This mesial rotation of the first upper molars mostly will be achieved by the first straight levelling archwire.
No information or disinformation may mean bodily harm, mismanagement and reliability for possible dental and Craniomandibular Dysfunction, CMD, or unnecessary extractions.
(from:http://www.cmd-orthodontics.com/)
the angulation of the 1st permanent molars,the key to functional occlusion
