Key points
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Vertical ridge augmentation is highly technique-sensitive and demands strict adherence to the PASS principles for successful grafting and healing.
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Severe defects require a form-stable, non-resorbable membrane to maintain space and stability, with at least 50% autogenous bone or optimal results.
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Preoperative planning is critical, including patient selection, medical history review, and realistic expectation management to avoid complications and failures.
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Customized mesh designs based on cone beam computed tomography (CBCT) imaging allow precise adaptation to anatomic defects, improving outcomes and reducing mesh exposure risk.
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Surgical success depends on tension-free closure, proper graft material selection, and meticulous postoperative care, with multistage treatments often needed for complex cases.
Abbreviations
| 3D | 3 dimensional |
| GBR | guided bone regeneration |
| TM | titanium mesh |
Introduction
Ridge augmentation procedures with a significant vertical component are the most complex cases to successfully graft due to technique sensitivity and high biological demands. The keys to success for ridge augmentation always rely on the (Primary wound closure, Angiogenesis, Space creation and maintenance, Stability [PASS]) principles. Primary closure without tension is difficult to achieve due to the amount of soft tissue advancement that is required for a closed healing environment. Additionally, these cases with more severe vertical defects often have minimal keratinized tissue and tissue of poor quality. Angiogenesis must reach a certain distance from existing bone for new bone to be formed. Space creation and maintenance for vertical ridge defects usually require the placement of tacks or screws to immobilize a nonresorbable membrane or titanium mesh (TM). Stability of the graft/membrane complex is crucial in order to counteract gravity and prevent mobility and collapse by the overlying soft tissue. In essence, these principles are more difficult to achieve and also more critical in order to ensure success.
Sites with fewer surrounding osseous walls and more pronounced atrophy require materials and/or techniques that offer greater biologic activity and regenerative capacity. It has been documented that guided bone regeneration (GBR) procedures that utilize a resorbable collagen membrane are limited to approximately 3 mm of vertical gain. Cases that require 5 mm of vertical gain or higher typically require a titanium-reinforced polytetrafluoroethylene (PTFE) membrane or a TM. Additionally, clinical studies suggest that at least 50% particulate autogenous bone is needed for greater vertical gains. The use of mineralized bone allograft mixed with recombinant human bone morphogenic protein-2 may be considered as an alternative to autogenous bone for TM grafting, but the cost is high.
A traditional TM does not conform to the anatomic shape of the area of a given bone defect, and intraoperative cutting and bending of the mesh may increase the risk of postoperative exposure and repeated mucosal irritation. Therefore, preformed, 3 dimensional (3D), customized barrier membranes with favorable mechanical properties would be preferable for ideal bone regeneration. This 3D fabrication allows it to perfectly adapt to the anatomic shapes of the bone defect areas, achieving a precise reconstruction of the lost volume.
Preop considerations and treatment planning
Choosing the correct cases to utilize this customized mesh is key in obtaining more predictable outcomes. Patient selection is important and systemic health and medications, drug allergies, patient compliance, and patient expectations set the foundation for success. Smokers, patients on immunosuppressants, antiresorptive drugs, or uncontrolled diabetes should be avoided. Patients with multiple drug allergies including penicillin and other antibiotics should be chosen carefully as delayed healing or postop infections may be difficult to manage. Patients who are demanding about having a prosthetic appliance too soon should also be cautioned that often times they are unable to wear anything for at least a couple weeks. It is critical that whatever the prosthesis is, it should never compress or apply pressure to the overlying soft tissue that covers the mesh.
Additionally, patients with unrealistic expectations, high demands or patients that may not be tolerable to a complication should be approached with caution. It is possible that multiple postop visits may be required, multiple rounds of antibiotics or antibacterial rinses may be needed, and patients need to be understanding of the possible nuances and complexities that come with these cases. Patients also need to be warned about the possibility of mesh exposure, graft contamination or infection, partial or complete loss of graft, and neurosensory disturbances. ,,
Choosing the appropriate ridge defects and sites are also critical to a successful outcome. Single tooth defects with recession and exposed roots on adjacent teeth should be avoided. It is crucial to understand that grafting more coronal than the level of the bony peaks of adjacent sockets is unrealistic and will lead to mesh exposure. In general, defects involving multiple teeth with a longer span are more predictable to graft due to flap management and manipulation of soft tissue. Third molars and malpositioned teeth in regions to be grafted should be considered for removal to create additional space for soft tissue closure ( Fig. 1 ).
Malpositioned tooth #31 was extracted at time of augmentation due to poor angulation and to help facilitate wound closure.
Case submission for a customized mesh is completed on the reoss.eu website and is fabricated based on the patient’s CBCT images—intraoral scans or impressions are not needed. Providing specific and detailed information may lead to a better design. For example, including planned implant sizes and ideal crestal bone dimensions, guides the engineer to more accurately design the mesh. A request for horizontal and vertical bone gains in the mesh design can also be made and will be provided in diagrams ( Fig. 2 A, B). It is also important for the mesh to be approximately 1.0 mm away from adjacent teeth and 0.5 to 1.0 mm apical to the level of the adjacent bony peaks to avoid mesh exposure. While surgical execution is important, an improper mesh design can inevitably lead to mesh exposure and possibly graft failure ( Fig. 3 ).
( A , B ) Diagrams of customized mesh design showing planned horizontal ( A ) and vertical ( B ) bone gain.
Example of mesh exposure caused by overcoronal positioning or improper design.
Surgical technique and intraoperative considerations
Case 1
A healthy gentleman in his mid-50s presented with a failing root canal treated tooth #29. He had been missing teeth #30, 31 for several years, and still had an erupted #32 which was mesioangulated. Because he had been missing teeth #30, 31 for several years, teeth #2 and 3 were supraerupted, leaving a minimal amount of interocclusal space ( Fig. 4 ). We discussed removing tooth #32 due to its malposition, as well as the potential of orthodontic intrusion of #3 versus endodontic therapy and a crown to create additional space. The patient and restorative dentist ultimately chose to endodontically treat #3 with a new crown, which was completed after ridge augmentation and prior to dental implant placement.
Pre-op panorex with malpositioned #32, supraerupted #2, 3 and failing tooth #29.
The design of the mesh was created to reconstruct the defect #30 to 31 but did not include the sockets of teeth #29 or 32, which we planned to extract at the time of ridge augmentation. The initial design was modified slightly to stay 1.0 mm away from the sockets of #29 and 32 and to keep the top of the mesh 0.5 mm apical to the level of the adjacent bony peaks ( Fig. 5 ).
Originl mesh design and modifications to move it 1.0 mm away from adjacent bony sockets and 0.5 mm apical to the level of the adjacent bone.
Once the flap was developed and teeth #29 and #32 were extracted ( Fig. 6 ), the mesh is seated in the planned site without graft material in order to predrill and ensure that the mesh is in the correct planned position ( Fig. 7 A, B). This is very important as overfilling the mesh with graft outside the mouth can lead to improper seating of the TM, which will lead to a more coronal position of the mesh, which can lead to mesh exposure.
Concave ridge deficiency, teeth #29 and #32 extracted.
( A , B ) Mesh seated without graft- notice the distance away from sockets and apical to the bone level.
Autogenous bone is harvested from the external oblique ridge/posterior ramus using a safescraper twist volumizer from Geistlich. These cases are grafted with at least 50% autogenous bone. Any remaining graft material needed is split 50/50 between mineralized allograft and xenograft. This mesh was secured with three 1.2 mm diameter, 6 mm length Stryker bone screws along the buccal in planned positions. A 30 × 40 mm biogide collagen membrane is placed over the mesh to allow for vascularization while creating a barrier to prevent soft tissue ingrowth ( Fig. 8 A, B). Adequate periosteal release on the buccal and lingual is paramount to achieve tension-free primary closure ( Fig. 9 ). The wound is first closed using 5.0 glycolon for the papilla sparing vertical release, followed by a double-layered closure with 3.0 PTFE. If the soft tissue is released appropriately, the wound edges should be easily everted just with a couple deep horizontal mattress sutures ( Fig. 10 ). A continuous or interrupted suture can be used just to reapproximate and close the wound edges ( Fig. 11 ).
( A ) Mesh seated with graft, secured with three 1.2 mm diameter, 6 mm length stryker screws ( B ) Mesh covered with 30 × 40 biogide membrane.
Adequate lingual flap release.
Horizontal mattress sutures to close deeper connective tissue layer and evert the wound edges (30 × 40 mm).
Continuous interrupted suture with 3.0 PTFE to close the wound edges without tension.
The patient is prescribed one week of amoxicillin, chlorhexidine mouth rinse to start 24 hours after surgery, and any necessary pain medications. The sutures are removed at the two week postop visit ( Fig. 12 ). Five months later, the patient is scheduled for a recheck prior to implant surgery to obtain a CBCT of the healed ridge to determine bone healing and implant sizes ( Fig. 13 ). The patient returned for implant surgery ten months after ridge augmentation ( Fig. 14 ). The bone had healed very nicely and part of the inferior aspect of the mesh had complete bone growth over it as well as the two posterior screws, which we decided to leave in place. A biohorizons tapered pro 4.2 × 10.5 mm was placed in site #29 and a 5.2 × 10.5 mm was placed in site #30 ( Fig. 15 ). We did not replace tooth #31 due to inadequate interocclusal space. Wide-platform (5.0 mm tall) healing caps were placed on both implants. The patient was cleared for final restorations three months later ( Fig. 16 ) and restored shortly thereafter ( Fig. 17 A, B).
Two weeks post-op, sutures removed at this visit.
CBCT 6 months post-op.
Ten months post-op, tooth #3 has been root canal treated with a new crown to create the necessary inerocclusal space.
Implants #29, 30 and integrated portion of the titanium mesh.
Final check three months post-op.
( A ) Final PFM crowns ( B ) Final restorations in occlusion.
Case 2
An otherwise healthy thirty year old male presented to us for implant retained prosthesis to rehabilitate missing teeth #s 6 and 7 that had been extracted a few months prior due to severe periodontal compromise. He had adequate soft tissue but a vertical and horizontal defect was noted ( Fig. 18 ).
Initial presentation.
A mesh was designed for improving the horizontal and vertical dimension of the alveolus, with special care for the mesh to be 1.0 mm away from the adjacent teeth. This mesh was also designed to have the future implant positions included on the occlusal aspect of the mesh.
A crestal incision with papilla sparing vertical releases on either site of the recipient site were performed to elevate a full thickness mucoperiosteal flap ( Fig. 19 ). Once adequate dissection is performed, the mesh is seated without graft and predrilled ( Fig. 20 ). Next, a 50/50 mix of autogenous shavings (obtained by tunneling to the right zygoma using a safescraper twist) and xenograft ( Fig. 21 ) were packed into the mesh and delivered into the surgical site.
Flap design, dissection up to the nasal floor.
Mesh seated without graft and pre-drilled.
50/50 autogenous plus xenograft.
Mesh was then secured with 1.2 mm screws × 3 ( Fig. 22 ) and covered with a Biogide membrane 20 × 30 mm (Geistlich Pharma North America Inc., Princeton, NJ; Fig. 23 ).
