CHAPTER 14 Case Presentations
An 18-year-old woman presented with complete anodontia. She had the dentoalveolar development of a 6-year-old in an adult skeleton. The lack of dentoalveolar development resulted in inadequate anterior-posterior (AP) support for the upper and lower lips. The patient had a decreased vertical dimension of occlusion (VDO) and a “wandering” acquired bite consistent with perpetual posturing of her mandible. She had partial primary dentition in her maxillary arch and used a removable prosthesis to replace the missing teeth at positions 8, 9, and 10. She had a full complement of primary mandibular teeth with stainless steel crowns on her anterior mandibular teeth (Figures 14-1 to 14-3).
To plan treatment with an implant-supported prosthesis, it was paramount to establish the proper VDO, AP tooth position, and a stable and reproducible occlusion. To accomplish this goal, maxillary and mandibular overdentures were fabricated. Occlusal adjustments were made during the next 4 months to establish a reproducible occlusion (Figures 14-4 to 14-8).
FIGURE 14-5 Maxillary and mandibular overdentures are used to re-establish the patient’s vertical dimension of occlusion and anterior-posterior tooth position, and to establish a reproducible “adult” hinge axis.
FIGURE 14-6 With the use of the overdentures, an increase in the height of the lower one-third of the face is observed, presenting a more balanced total facial height. Proper vertical dimension of occlusion and anterior-posterior tooth positioning allows for aesthetically acceptable nasolabial and labiomental profiles.
Prior to planning treatment with implants, cone beam radiographic studies of the temporomandibular joints were completed. These studies demonstrated an absence of pathologic conditions in the joint and established a baseline study for comparison with future cone beam radiographic studies of the patient’s joint (Figure 14-9).
FIGURE 14-10 A composite defect is apparent when relating the cervical portion of the clear denture teeth to the patient’s alveolar crest. This finding indicates that fabrication of a final profile prosthesis for both the maxilla and the mandible is appropriate.
FIGURE 14-12 Maxillary and mandibular cone beam radiographic studies are consistent with narrow crestal alveolar width, which indicates the need for alveolectomies after removal of the maxillary and mandibular primary dentition.
FIGURE 14-14 After establishing the desired implant length using the 2-mm start drill, paralleling pins are placed to allow better visualization of the proposed implant sites in the anterior-posterior dimension and in the buccal-palatal dimension (especially the posterior tilted implants).
FIGURE 14-15 After implant placement with 40 Ncm insertion torque, 30° multiunit abutments are placed on the posterior tilted implants. For the anterior implants, temporary healing abutments are placed prior to indexing the positions of the implants with the intaglio surface of the denture.
FIGURE 14-16 After indexing the position of the implants, the denture is placed passively over the abutments. At this point, the decision is made to either use straight multiunit abutments or 17° multiunit abutments for the anterior maxillary implants.
FIGURE 14-18 An envelope flap exposes the mandibular alveolus. The primary teeth are removed with a complete alveolectomy. The relationship of the mental foramina to the crest of the edentulous alveolus is observed bilaterally.
FIGURE 14-19 The implants are placed using the tilted treatment concept. If 40 Ncm insertion torque is maintained, 30° multiunit abutments are secured to the posterior implants, bringing the platform of the tilted implants in line with the platform of the anterior axial implants.
FIGURE 14-20 Indexing material is used to transfer the implant positions to the intaglio surface of the mandibular immediate denture. After choosing straight or 17° multiunit abutments for the anterior implants, the denture is converted to a provisional profile prosthesis and secured to the abutments with temporary titanium cylinders.
FIGURE 14-22 A panoramic radiograph taken immediately after surgery demonstrates a proper relationship between the tilted maxillary implants, the anterior maxillary wall, the tilted mandibular implants, the mental foramina, and the loop of the inferior alveolar nerve.
FIGURE 14-23 Photographs taken 1 week after surgery demonstrate proper vertical dimension of occlusion, balanced facial thirds, an aesthetically acceptable smile line, and a hidden maxillary transition lone.
FIGURE 14-24 Six months after removal of the teeth, an alveolectomy, and immediate loading of the maxilla and the mandible, the final metal-based profile prosthesis is completed with a favorable hidden transition line.
A 24-year-old healthy man presented with ectodermal dysplasia. The facial form indicated collapse of the nasolabial and labiomental angles. In the treatment planning phase, careful consideration must be given to the transition line of the final prosthesis. The intraoral presentation demonstrated partial maxillary and mandibular malformed teeth. A flat maxillary vault and advanced horizontal atrophy of the mandibular residual alveolus were also apparent. The patient maintained maxillary and mandibular removable partial dentures, which were not functional (Figures 14-27 to 14-31).
FIGURE 14-27 A, Improper vertical dimension of occlusion and anterior-posterior tooth support results in collapse of both the nasolabial and labiomental angles. B, The potential for a transition line visible during animation should be considered during treatment planning.
The patient’s panoramic radiographic examination demonstrated a prominent premaxilla and advanced resorption of the posterior maxillary alveolus. The mandible had moderate to advanced resorption in the vertical dimension with retained cuspids only. The presence of zone I bone only indicated that the zygoma treatment concept was appropriate for reconstruction of the maxillary dentition with a fixed profile prosthesis. The tilted implant concept may be considered for treatment of the mandible with a fixed, implant-supported prosthesis (Figure 14-32).