It is almost a routine practice to remove malposed impacted lower 3rd molars for the following reasons: pericoronitis, proximal caries or periodontal pocket formation due to difficulty in cleaning space between lower 2nd and 3rd molars.
Some may also argue they could cause post orthodontic treatment crowding.
There are many disadvantages of removing the horizontally impacted 3rd molars: numbness of the lower lip due to damage to the mandibular nerve, pocket formation on the distal side of lower 2nd molar, difficult to fill the distal caries of lower 2nd molar, challenging extraction and related post extraction pain and swelling.
In traditional edgewise treatment, it’s quite difficult to correct severe Class III malocclusion without extraction of lower premolar or molars, unless using the MEAW technique, well known in Asia to be a powerful multiloop system to correct Class III without premolar or molar extraction ( except 3rd molars).
Recently due to advanced development of passive self-ligating brackets (ie, the Damon system) and TADs (Temporary Anchorage Devices), most of the difficult Class III cases, with acceptable profiles (not too prognathic and patient can accept), can be treated without using MEAW or extraction of premolars or molars.
In traditional orthodontics, horizontally impacted lower 3rd molars are almost routinely removed for comprehensive orthodontic treatment. In one of my cases the oral surgeon refused to remove the horizontally impacted lower 3rd molars due to the root proximity to the mandibular canal.
As such, the author had to reluctantly remove the lower 2nd molar, instead of the impacted 3rd molar. Despite initial concerns over uprighting the horizontally impacted lower 3rd molars, the author successfully uprighted the 3rd molars. The key is to provide enough space by extracting the 2nd molar.
In this article, extraction of the lower 2nd molar to solve horizontally impacted lower 3rd molars will be presented, it can be a very good clinical option to avoid painful and difficult extraction of impacted lower 3rd molars.
