Types of Bone AugmentatioN
Evidence suggests that for vertical ridge augmentation of up to 4 mm, techniques such as DO, inlay bone grafting, onlay block grafting, and GBR are all reliable. However, DO and inlay grafting are superior when greater vertical augmentation is required. Among these techniques, GBR shows the lowest complication rates and vertical bone resorption, while implant survival and success rates are high across all methods (Elnayef et al., 2017; Esposito et al., 2009).
Guided Bone Regeneration (GBR):
- Description: GBR is a widely used technique for promoting new bone formation by using bone substitutes like allografts, xenografts, and synthetic materials, along with barrier membranes. These membranes can be either resorbable or non-resorbable and are placed over bone defects to maintain space and create an optimal environment for bone growth (Troeltzsch et al., 2016).
- Preferred Method: The combination of xenografts and resorbable membranes is the most frequently used approach in GBR (Sanz-Sanchez et al., 2015). Bioactive factors such as platelet-derived growth factor (PDGF), insulin-like growth factor (IGF), and bone morphogenic proteins (BMPs) have been studied to further enhance osteogenesis (Almela et al., 2017).
- Outcomes: GBR is considered a predictable technique for placing implants in atrophic areas, with implant survival rates above 90% in most studies, similar to those in normal ridges (Hammerle et al., 2002; Clementini et al., 2012).
Sinus Lift (Sinus Augmentation):
- Lateral Window Technique: Involves accessing the maxillary sinus through a lateral wall approach, which allows for the elevation of the sinus membrane and placement of graft material (Boyne & James, 1980).
- Crestal Lift: A less invasive technique where the sinus is accessed through the existing bone via the osteotomy site, often preferred for cases requiring minimal augmentation (Summers, 1994).
Ridge Expansion:
- Split Ridge Technique: This technique is used to expand the alveolar ridge, making it wide enough to accommodate implants. The procedure involves a segmental osteotomy of the ridge and placing bone graft materials within the split ridge. Although technically challenging, it has a high success rate for both bone augmentation and implant survival (Mestas et al., 2016).
Distraction Osteogenesis (DO):
- Bone Lengthening: DO is a technique that encourages new bone formation by gradually separating bone segments at an osteotomy site. This method does not require bone graft harvesting and has been effectively used for vertical and horizontal ridge augmentation. DO enables simultaneous augmentation of both bone and soft tissue, with predictable outcomes (Yun et al., 2016).
- Application: DO is particularly effective for cases requiring significant vertical ridge augmentation, as it has shown superior results compared to other techniques when more than 4 mm of vertical growth is needed (Elnayef et al., 2017).
Onlay Block Grafting:
- Autologous Bone Grafts: Involves harvesting bone from intraoral sites like the mandibular symphysis or extraoral sites like the iliac crest and placing it as a block graft onto the prepared recipient site. This technique is effective for both horizontal and vertical ridge augmentation, with implant survival rates ranging from 96.9% to 100% for horizontal augmentation and 89.5% to 100% for vertical augmentation (Aloy-Prosper et al., 2015).
- Combined with GBR: Combining block grafting with GBR by using a membrane over the autologous block graft reduces the graft's resorption rate, making it a predictable surgical technique (Antoun et al., 2001).
We would like to acknowledge Dr. Manraj Kalsi for his insights and contributions to this page