The maxillary sinus will likely interfere with the placement of an implant of desirable length, necessitating sinus modification surgery such as a sinus graft or a vertical upfracture. Restoration: MCR over a custom abutment (UCLA, Atlantis, or preparable abutment)
Missing: Mandibular second premolar Abutments: First premolar and first molar Considerations: Esthetic requirements of the patient may necessitate an MCR retainer on the molar. Resin-bonded retainers can be used if the first premolar is large and if the abutments are caries-free or only minimally affected by caries. Retainers: MCR crown on the premolar and FGC on the molar Pontic: Modified ridge lap or ovate MCR Abutment-pontic root ratio: 3.1
Missing: Mandibular second premolar Implant: 4.3 × 10 mm Considerations: Loss of the facial plate of bone may result in inadequate alveolar width. Alveolar resorption may result in insufficient height of bone above the mental foramen and mandibular canal. The correction of this anatomical difficulty requires the placement of an onlay bone graft to allow the placement of an implant of sufficient width and length. Restoration: MCR over a custom abutment (UCLA, Atlantis, or preparable abutment)
Missing: Maxillary first molar Abutments: Second premolar and second molar Retainers: MCR or ¾ crown on the premolar and ⅞ crown on the molar Pontic: Modified ridge lap MCR Abutment-pontic root ratio: 1.5
Missing: Maxillary first molar Implant: 5.0 × 11.5 mm Considerations: The maxillary sinus will likely interfere with the placement of an implant of desirable length, necessitating sinus modification surgery such as a sinus graft or a vertical upfracture. Restoration: MCR over a custom abutment (UCLA, Atlantis, or preparable abutment)
Missing: Mandibular first molar Abutments: Second premolar and second molar Considerations: A tilted molar may require orthodontic uprighting, a proximal half crown, or a telescope crown (see chapter 7). Retainers: MCR crown on the premolar and FGC on the molar Pontic: All-metal hygienic, if patient is agreeable. If the patient demands a ceramic occlusal portion, a pontic design that touches the ridge is needed, and metal should extend fully to the ridge to provide rigidity. Abutment-pontic root ratio: 1.5
Missing: Mandibular first molar Implant: 5.0 × 10 mm Considerations: Loss of the facial plate of bone may result in inadequate alveolar width. Alveolar resorption may result in insufficient height of bone above the mandibular canal. The correction of this anatomical difficulty requires the placement of an onlay bone graft to allow the placement of an implant of sufficient width and length. Restoration: MCR over a custom abutment (UCLA, Atlantis, or preparable abutment)
Missing: Maxillary second molar Considerations: Restoration with a cantilevered fixed partial denture is not recommended due to the excessive tensile stresses placed on the premolar abutment and the retainer. Missing: Maxillary second molar Implant: 5.0 × 11.5 mm Considerations: The maxillary sinus will likely interfere with the placement of an implant of desirable length, necessitating sinus modification surgery such as a sinus graft or a vertical upfracture. Restoration: MCR over a custom abutment (UCLA, Atlantis, or preparable abutment)
Missing: Mandibular second molar Considerations: Restoration with a cantilevered fixed partial denture is not recommended due to the excessive tensile stresses placed on the premolar abutment and the retainer. Missing: Mandibular second molar Implant: 5.0 × 10 mm Considerations: Loss of the facial plate of bone may result in inadequate alveolar width. Alveolar resorption may lead to insufficient height of bone above the mental foramen and mandibular canal. The correction of this anatomical difficulty requires the placement of an onlay bone graft to allow the placement of an implant of sufficient width and length. Restoration: MCR over a custom abutment (UCLA, Atlantis, or preparable abutment)
Complex Fixed Partial Dentures (One Tooth)
Missing: Maxillary canine Abutments: Central incisor, lateral incisor, and first premolar Considerations: A single implant-supported MCR crown would be the restoration of choice here. Restore the occlusion to group function. Using the two premolars and the lateral incisor as abutments is not desirable because it places too heavy a burden on the smaller single abutment, the lateral incisor. Retainers: MCR crowns Pontic: Modified ridge lap or ovate MCR, depending on the faciolingual dimension of the ridge Abutment-pontic root ratio: 2.3
Missing: Maxillary canine Implant: 4.5 × 15 mm Considerations: A dental implant is the restoration of choice. Restoration: MCR over a custom abutment (UCLA, Atlantis, or preparable abutment)
Missing: Mandibular canine Abutments: Central incisor, lateral incisor, and first premolar Considerations: An implant-supported MCR is the restoration of choice in the mandible as well. Use group function to restore the occlusion. If there has been extensive bone loss around the lateral incisor, or if it is tilted to produce a line of draw discrepancy, remove the lateral incisor and use both central incisors as abutments if a fixed partial denture is used. Fortunately, the need to replace this tooth is not common. Retainers: MCRs Pontic: Ovate MCR Abutment-pontic root ratio: 1.9
Missing: Mandibular canine Implant: 4.5 × 15 mm Considerations: A dental implant is the restoration of choice. Restoration: MCR over a custom abutment (UCLA, Atlantis, or preparable abutment)
Simple Fixed Partial Dentures (Two Teeth)
Missing: Maxillary central incisor and lateral incisor Abutments: Central incisor and canine Considerations: If the central incisor and canine are unblemished and unusually large, pin-modified partial coverage crowns could be used. Patient acceptance and dentist skill are strong considerations. Retainers: MCRs Pontics: Modified ridge lap MCR Abutment-pontic root ratio: 1.2
