Maxillary molar anchorage preservation

Drs. Larry W. White and Francesca Scilla Smith discuss a technique for maxillary molar anchorage preservation

Maxillary molar anchorage has perplexed orthodontists since the beginning of premolar extraction therapies. Every clinician knows from sad experience that maxillary molars easily displace and rotate mesially when challenged with mesial space and force. Obvious and early remedies — e.g., transpalatal arches,¹ Nance arches,² intermaxillary Class II elastics,³ and headgears⁴ (Figure 1) — proved incapable of providing reliable molar anchorage. More recently, the use of miniscrews has enjoyed some popularity although they require local anesthesia while also bringing more expense and often equivocal stability. Melsen and Fiorelli⁵ have advocated the use of occlusal anchorage enhancements using Triad^® light-cure gel (Dentsply Sirona, Charlotte, North Carolina) (Figure 2).

Recently, a variation of the Melsen and Fiorelli occlusal pads has proven effective and doesn’t require the occlusal coverage of mandibular molars and premolars, while providing a more defined stop for the maxillary second premolar when maxillary first premolars have been extracted (Figures 3 and 4). This places an occlusal stop solidly against the maxillary second premolar and, as seen, prevents the maxillary posterior teeth from moving forward. For want of a proper name, these are called Anchorage Posterior Occlusal Guides, aka, APOGs.

The APOGs are made using the Bite Ramp Mini Mold™ (Ortho Arch Company, Schaumburg, Illinois). The mold is filled with the Triad gel and applied to the distal occlusal surface of the mandibular first premolar and light-cured. If upon removing the mold, the APOG doesn’t touch the maxillary second premolar, a small amount can be applied to the scaffolding of the bite ramp until it makes contact with the upper tooth. If the mold touches prematurely, it is easily smoothed to fit with an air turbine bur.

Clinicians can apply APOGs easily and quickly with minimum armamentarium, small cost, and no laboratory involvement, while using the ever-present occlusion as reinforcement for posterior maxillary anchorage in maxillary premolar extraction patients.