“Rules of 10”—Guidelines for Successful Planning and Treatment of Mandibular Edentulism Using Dental Implants

[Drsumitra]

 Applying the Rules of 10

Several key steps are required for using the Rules of 10 in the treatment of mandibular edentulism. The previously mentioned reference points (ie, occlusal plane and osseous crest) must be firmly established. To assure accurate measurement, all treatment should begin with the proper fabrication of complete dentures and verification of ideal tooth position (Figure 10 and Figure 11).

Rule No. 1 requires a volumetric assessment of the edentulous mandible with cone-beam computed tomography (CBCT). However, other important information can be found in the radiographic process, and no radiograph should be made for ISFP treatment-planning purposes without the presence of a radiographic stent. The resultant image(s) should display the location of the planned prosthesis in relation to the mandible.

Rule No. 2 requires that the plane of occlusion is properly located and the appropriate vertical dimension of occlusion is defined. If the patient is also edentulous in the maxilla, this involves the fabrication of ideal maxillary and mandibular dentures. The dentures will define the location of the occlusal plane and mandibular tooth position, where the mandibular denture can be duplicated in radiopaque acrylic for a radiographic stent. The amount of alveolectomy needed can then be determined from the CBCT images.

Rule No. 3 requires an understanding of the anatomy of the edentulous mandible in relationship to the location of the planned prosthetic teeth, as well as the ability to translate this information to the implant placement, generally via a surgical guide. This can be accomplished practically in one of two ways. One method involves evaluation of the CBCT images using 3-D planning software (eg, Materialise Simplant^®, Materialise Dental, http://www.materialise.com; NobelClinician™, Nobel Biocare, http://www.nobelbiocare.com) and then modifying a duplicate denture made from clear acrylic (Figure 10 and Figure 11). The other involves use of a third-party company to fabricate a digital surgical guide.

Conclusion

Dental implant therapy for the edentulous mandible has been successful. Data concerning implant survival is high and reflects the quality and quantity of bone available for osseointegrated implant function. The complications associated with both removable and fixed dental implant prostheses reflect the constraints of current materials and design limitations. The Rules of 10 assure that there is: 1) adequate bone for osseointegration and its long-term success; 2) sufficient dimension for fabrication of an esthetic, comfortable, and robust prosthesis; and 3) proper distribution of imposed forces from occlusal function within the prosthesis, at the implant/abutment screw interfaces, and at the implant/bone interfaces. Following these simple geometric and linear guidelines to treatment planning enables proper implant placement decisions that underscore robust and lasting prosthesis construction.