The D-Gainer Appliance, Part I
By Dr. Adrian J. Palencar, MUDr, MAGD, IBO, FADI, FPFA, FICD
As I alluded to in the previous IAO Monthly Tip, if the second deciduous molars are firm, it is an advantage, because two deciduous molars and two permanent molars create a reasonable anchorage for proclination and bodily movement of four incisors.
However, when we have only first permanent molars available, there will be a distal moment (tipping) on the molars as the expression of the Third law of Newton (for every action is equal and opposite reaction). If no movement is desired on the permanent molars, the author suggests cemented maxillary TP arch and mandibular Lingual arch as an anchorage.
If distal tipping and bodily movement of first molars is desirable, the D-gainer appliance can create an amazing amount of space by distalization of the first molars, mesialization of the incisors and spontaneous transverse development.
When inserting the .018 SS arch wire into the molar tubes observe the anterior portion. The arch wire is most often below the bracket slots of the incisors because of inherent mesial tipping during the eruption of the molars. This will result in slight intrusion of the incisors, which is desirable in closed bite cases. However, this is not desirable in an anterior open bite case.
In the case where more bodily movement of incisors is required, rather than labial moment (proclination), the author suggests:
- Use rectangular arch wire, i.e., a .016×022 SS
- Use negative torque incisor brackets, or
- Reverse the incisor brackets in the maxilla from +17 degrees, +8 degrees to -17 degrees, -8 degrees, or
- Apply negative crown torque to the rectangular arch wire with Torquing pliers with the key, or Ross torquing pliers from the lateral incisor to the lateral incisor
- Carefully monitor the labial aspect of the gingival margins and the attached gingiva for recession and dehiscence
- Dr. Derek Mahony, lecture attendance
- Palencar A. J. Personal PP presentations