Case presentation : Case report on managing incomplete bone formation after bilateral sinus augmentation using a palatal approach and a dilating balloon technique [3]
A year later, we requested cone beam computed tomography for both posterior maxilla sites, and we found incomplete bone growth in the sinus. On the right side, bone growth had occurred only distal to the desired implant site, and there was an ovoid extension of sinus into the area planned for implant placement (Fig. 4). On the left side, a finger-like extension of sinus had developed between grafted bone and the former inferior medial wall of the sinus (Fig. 5). After explanation of findings, treatment alternatives, and risks and benefits of proposed treatments, the patient agreed on continuing with additional bone grafting.
For the right side, we decided to augment the area of insufficient bone using a balloon dilation technique through a subantral approach since the area of the missing bone was nearly spherical and centered at the no. 3 site. We also decided to place an implant simultaneously since primary stability seemed likely with the consistent thickness of 5 mm available bone at the no. 3 site, consistent with the recommendation by Pjetursson and Lang [19]. We created sinus access in a similar fashion as developed by Tatum in the 1970s and described by Misch [20] and performed sinus augmentation with a balloon technique as described for lateral window augmentation by Muronoi et al. [6]. (See Fig. 6 for the actual procedure, Fig. 7 for a diagram.) For this surgery, we created a mucoperiosteal flap with buccal releases for improved access (Fig. 6a, b) and created an osteotomy using osteotomy drills (Fig. 6c; Zimmer implant surgical kit, Zimmer, Carlsbad, CA, USA). Since there was sufficient ridge width and the bone was hard, we opted not to use Summer’s technique [21] but used drills to take the osteotomy to its final width that was slightly undersized for a 4.7-mm implant, but wide enough to allow insertion of a balloon dilator (straight model, Osseous Technologies of America, Hamburg, NY, USA). Drilling of the osteotomy stopped short 1 mm of the sinus floor. Prior to balloon dilation, we mobilized the Schneiderian membrane by gently infracturing small segments of the osteotomy floor using thin flat-ended osteotomes (ACE Surgical Supply, Brockton, MA, USA). For this, we started in the center of the osteotomy, advanced the depth of the infracture by 1 mm with a mallet and worked in a spiral fashion to the outer limits of the osteotomy floor and apical most 2 mm of the osteotomy wall. We then used a larger flat osteotome to advance the entire floor of the osteotomy by another millimeter, which resulted in a rubber-like mobility of the osteotomy floors. We verified the integrity of the membrane by gentle probing with a WHO probe and inserted the balloon dilator (Fig. 6d–g). We then slowly inflated the balloon dilator with 1 ml of saline, verified integrity of the membrane again, placed two sheets of 1 cm × 1 cm × 1.5 resorbable collagen tape, followed by 0.5 ml allograft and a 4.7 × 10 mm rootform implant (Fig. 6h–j; Tapered Screw-Vent TSVWB10, Zimmer, Carlsbad, CA, USA), which achieved good primary stability in excess of 30 Ncm. We placed a cover screw, replaced the flap, and sutured it with a continuous chromic gut 4-0 suture (Fig. 6k). Postoperative radiographs verified implant placement and showed good confinement of graft material around the implant (Fig. 6l). Healing was uneventful with only mild short-lived postoperative pain for a few days, and implant uncovery 12 months later revealed a firmly embedded implant.
Serial posts:
- Background : Case report on managing incomplete bone formation after bilateral sinus augmentation using a palatal approach and a dilating balloon technique [1]
- Background : Case report on managing incomplete bone formation after bilateral sinus augmentation using a palatal approach and a dilating balloon technique [2]
- Case presentation : Case report on managing incomplete bone formation after bilateral sinus augmentation using a palatal approach and a dilating balloon technique [1]
- Case presentation : Case report on managing incomplete bone formation after bilateral sinus augmentation using a palatal approach and a dilating balloon technique [2]
- Case presentation : Case report on managing incomplete bone formation after bilateral sinus augmentation using a palatal approach and a dilating balloon technique [3]
- Case presentation : Case report on managing incomplete bone formation after bilateral sinus augmentation using a palatal approach and a dilating balloon technique [4]
- Case presentation : Case report on managing incomplete bone formation after bilateral sinus augmentation using a palatal approach and a dilating balloon technique [5]
- Conclusions : Case report on managing incomplete bone formation after bilateral sinus augmentation using a palatal approach and a dilating balloon technique
- References : Case report on managing incomplete bone formation after bilateral sinus augmentation using a palatal approach and a dilating balloon technique [1]
- References : Case report on managing incomplete bone formation after bilateral sinus augmentation using a palatal approach and a dilating balloon technique [2]
- Acknowledgements : Case report on managing incomplete bone formation after bilateral sinus augmentation using a palatal approach and a dilating balloon technique
- Author information : Case report on managing incomplete bone formation after bilateral sinus augmentation using a palatal approach and a dilating balloon technique
- Rights and permissions : Case report on managing incomplete bone formation after bilateral sinus augmentation using a palatal approach and a dilating balloon technique
- About this article : Case report on managing incomplete bone formation after bilateral sinus augmentation using a palatal approach and a dilating balloon technique
- Fig. 1. Initial presentation. Panoramic radiograph taken at initial visit shows severe bone loss, supraerupted molars and furcation involvement : Case report on managing incomplete bone formation
- Fig. 2. Right sinus prior to first sinus grafting procedure. Cone beam CT imaging shows very little residual bone volume at implant site for the no. 3 area : Case report on managing incomplete bone formation
- Fig. 3. Left sinus prior to first sinus grafting procedure. Cone beam CT imaging also shows very little bone volume on left side for the no. 14 area : Case report on managing incomplete bone formation
- Fig. 4. Right sinus about 12 months after first grafting procedure. Cone beam CT imaging shows little suitable bone at implant site, but grafted bone displaced distal to site. Bone hydroxyapatite particles were added as radiographic marker to the graft material for the first sinus augmentation procedure and are still visible as radiopaque specks : Case report on managing incomplete bone formation
- Fig. 5. Left sinus about 12 months after first grafting procedure. Cone beam CT imaging shows unusual sinus anatomy after grafting, with finger-like sinus extension at implant site, and thick-grafted bone buccal and apical to it. The infractured wall is still clearly visible, as well as the bovine bone particles used as radiographic marker : Case report on managing incomplete bone formation
- Fig. 6. Right sinus balloon dilation procedure. This photographic series shows the surgical procedure that augmented bone and allowed implant placement at the no. 3 site. a Preoperative view after infiltration anesthesia. b Full-thickness midcrestal incision. c Osteotomy preparation with implant drills and osteotomes. d, e The dilating balloon, which is inflated using saline pressure from a syringe. f Insertion of uninflated balloon into osteotomy. g Gentle inflation of balloon by 1 ml. h Preparation of allograft and collagen tape. i Collagen tape is visible at bottom of osteotomy after filling expanded Schneiderian membrane with bone graft and covering graft with collagen tape. j Implant placement. k Suturing with a continuous suture. l Postoperative radiograph showing implant and halo of allograft surrounding apex of implant after surgery : Case report on managing incomplete bone formation
- Fig. 7. Schematic diagram of sinus balloon dilating procedure. This diagram shows how the balloon is inserted into a small transcrestal osteotomy and then expanded with balloon : Case report on managing incomplete bone formation
- Fig. 8. Blood supply of the sinus. There are three areas in the sinus where blood vessels may be encountered during sinus augmentation procedures for implants. On the inflection point between hard palate and alveolar ridge in the posterior maxilla, the greater palatine neurovascular bundle is located embedded in soft tissue. This inflection point is matched in the internal sinus anatomy and presents a landmark that can be palpated with sinus curettes during sinus membrane elevation or seen on cone beam CT images in this patient. It is important to avoid instrumenting the area above this inflection point as branches of the lateral posterior nasal arteries may be encountered superior to this area. Injuring these blood vessels can lead to significant sinus bleeding that is difficult to stop without sinus tamponade. Often on cone beam CT images, we see a small blood vessel channel midway within the lateral wall of the sinus, which likely is the posterior superior alveolar artery and vein.
- Fig. 9. Schematic diagram of palatal approach sinus augmentation. The diagram shows the location of the lateral window, avoiding the thick grafted bone on the buccal, and the greater palatal neurovascular bundle : Case report on managing incomplete bone formation
- Fig. 10. Palatal approach lateral window sinus augmentation. This photographic series shows the surgical procedure that augmented bone and allowed implant placement at the no. 14 site. a Preoperative view prior to infiltration anesthesia. b Full-thickness midcrestal incision with palatal release and flap elevation. This was aided by a small bony ridge that separated the alveolar crest from the soft tissue area containing the greater palatine neurovascular bundle. c Sinus window created with piezosurgery. d–f With gentle piezocision and water pressure, the finger-like membrane is slowly mobilized and collapsed towards the remainder of the sinus cavity. The overlying bone serves to form a new floor covering the base of the finger-like cavity. f Conventional implant placement using osteotomy drills. g Any exposed sinus membrane is covered with collagen tape. h Particulate mineralized allograft is placed into the newly created space. i A resorbable collagen membrane is placed over the acce
- Fig. 11. Implant restoration. Implants were restored by dental students supervised by prosthodontists at the Dental Center : Case report on managing incomplete bone formation
- Fig. 12. Radiographic bone levels three years after placement. Bone levels remain unchanged during long-term follow-up : Case report on managing incomplete bone formation