Bone and Soft Tissue Augmentation in Implantology

In the rare case of vertical bony defects where the remaining bone still has a wide platform of > 8 mm, independent of the region, sandwich grafting or distraction osteogenesis can be considered as an alternative to 3D bone reconstruction. For this purpose, a residual bone height of at least 6 mm is necessary so that the distractor can be sufficiently anchored in the local bone and a segment can be mobilized. Distraction osteogenesis is also suitable for the entire mandible under the same conditions. The patient acceptance for such a treatment is limited due to the 2- to 3-month disturbance caused by distraction devices.

In cases of vertical bony defects in the posterior mandible, the elongation of the teeth in the adjacent jaw and the available space for prosthetic reconstruction should be checked on the basis of the clinical situation and articulated models ( Fig 2-22ato f). If a sufficient maxillomandibular distance is available for an absolute reconstruction of the alveolar crest for the future prosthetic construction, a choice exists between a 3D bone augmentation, a sandwich grafting or a distraction osteogenesis to restore the necessary bone volume. If the maxillomandibular distance is restricted and does not allow for any correction, e.g. reducing the volume of the antagonist teeth, then the method of nerve lateralization in connection with the implant placement could be considered.

In cases of vertical bony defects in the posterior maxilla, the maxillomandibular distance should be checked, as in the mandible. If there is sufficient maxillomandibular distance for a vertical bone augmentation, then a 3D augmentation with autogenous bone blocks with or without sinus floor elevation is recommended ( Fig 2-23ato d). This is important so that the later crowns obtain a normal dimension, which also has not only esthetic but also hygienic significance in this region. Implants inserted in cases of important vertical bone loss in the posterior maxilla without vertical bone augmentation are very difficult to restore and to clean ( Fig 2-23eand f). After a short time, this will lead to peri-implantitis. If the maxillomandibular distance is limited, implant placement is performed in conjunction with or after a sinus floor elevation.

Fig 2-22aBone atrophy in the bilateral free-end situation.

Fig 2-22bThe scope of the vertical defect is clearly visible in the articulator.

Fig 2-22cSimulation of the necessary grafting volume in wax.

Fig 2-22dWax-up of correct tooth length in the left mandible.

Fig 2-22ePanoramic radiograph documenting a bilateral vertical bone augmentation in the right and left posterior mandible. The right bone graft is very close to the antagonist elongated second molar.

Fig 2-22fPanoramic radiograph documenting the implant insertion after reducing the graft volume. An endodontic treatment was also performed on the antagonist elongated tooth after reducing its volume.

Fig 2-23aSchematic illustration of a class C vertical bone defect according to Chiapasco et al. 18

Fig 2-23bSimultaneous implantation with sinus floor elevation in class C, with the consequence of an unfavorable crown–implant ratio.

Fig 2-23cSchematic illustration of vertical grafting in a class E defect to create a physiologic course for the alveolar ridge.

Fig 2-23dSchematic illustration of implants placed after vertical reconstruction with a balanced crown–implant ratio.

Fig 2-23eIncorrect implant insertion in the posterior left maxilla.

Fig 2-23fPanoramic radiograph documenting the extreme apical position of the implants.

Fig 2-24aClinical situation before treatment: closed bite and severe periodontal disease.

Fig 2-24bAfter periodontal treatment involving the extraction of the hopeless teeth and a fixed temporary restoration, vertical bone grafting in different areas of the maxilla with bone blocks from the mandibular left retromolar area. The external oblique was so pronounced that only one intraoral donor site was sufficient for the entire maxillary reconstruction.

Fig 2-24cControl radiograph 7 years postoperatively with a stable peri-implant bone level.

Fig 2-24dClinical situation 7 years postoperatively.