Discussion

In this case report, a customized patient-specific lattice structure was used for horizontal and vertical augmentation in the posterior mandible. It offered a precise fit and high stability after screw fixation as already proven in recent studies for preformed meshes. A customized mesh shortens duration of surgery and offers all benefits of reduced time for intervention and improved surgical management, as well as a decreased exposure time to general anesthesia, decreased blood loss, and shorter wound exposure. With its advantages such as biocompatibility, corrosion resistance, and three-dimensional stability, titanium meshes have proven to be useful in the reconstruction and augmentation of oral and maxillofacial defects. Studies have demonstrated that the inherent rigidity of stiff titanium mesh supports the grafted space and prevents soft tissue collapse. Six months after removal of the mesh, osseous grafts protected by a titanium mesh showed significantly less bone resorption compared with an overlay bone graft alone.

The round and blunt edges of the mesh used in this case prevents mucosal irritation. In the field of implant dentistry, a customized titanium mesh was already proven to be suitable for stabilization of bone regeneration. A recent study proved a printed titanium mesh for alveolar bone reconstruction using a bone morphogenetic protein 2/absorbable collagen sponge 7 (BMP-2/ACS7) allograft to be a possible improvement to hand-configured mesh graft techniques. Ciocca et al prepared a customized titanium mesh to augment the atrophic alveolar ridge and demonstrated satisfactory bone regeneration. A preliminary evaluation of a three-dimensional, customized, and preformed titanium mesh to regenerate alveolar bone proved its efficacy. However, in these protocols, a possible loss of augmentation material in the course of mesh removal may occur. In this case, the removal of the lattice structure caused no fracturing of the augmented bone or damage to soft tissue because of the novel removal function. There were no signs of displacement or compression, and the augmented area showed no resorption processes. Additionally, the time of the second surgery was obviously reduced. Thus, the titanium lattice structure stabilized the defect area and its augmentation material and helped to rebuild the osseous defect to provide enough bone for implant placement procedures. The bony level remained stable even after a longer period, which may be due to the formation of “real new” bone. In addition, histologic examination revealed these new, mature bony structures tightly adherent to the residual bone.

The presented technique included three-dimensional planning and printing, allowing an easy application and convenient removal, together with a stable formation of local bone with no peri-implant bone loss. During the last few years, multiple techniques combining medical imaging and rapid manufacturing techniques were published. The two most frequently used rapid prototyping technologies are stereolithography and three-dimensional printing (3DP). 3DP seem to be superior compared with stereolithography because this procedure provides better accuracy and quicker printing time. In the novel protocol at hand, the surgeon is included into the designing process. This modern, digital workflow as part of daily augmentation procedures may result in an improved clinical outcome.

Dental implants bridged to a natural tooth represent a controversial topic in dentistry because of differences in resiliency. A natural tooth's periodontal ligament work as a shock absorber during clenching and chewing. This is not the case for well-osseointegrated dental implants. These differences in resiliency may lead to complications involving tooth eruption, failure of the bridge, fracturing of implant or screw components. Alternatives such as the placement of two implants or other bridge constructions were rejected by the patient.