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Significant reabsorption may occur after extraction, which is a common clinical problem. Since the density of this bone is lower compared to the mandibular arch, this may be more prominent in the front of the upper jaw. The extent to which absorption occurs is related to many factors, including the patient’s age, healing ability, medical health, and the reason for the tooth extraction (menstruation, endometrium, trauma, or a combination of these factors). In addition, bone maintenance involves stimulating bones through functions related to the transfer of loads through teeth (or implants). However, when the irritation is removed by tooth extraction, the surrounding bones will shrink (reabsorb). Some patients will show minimal bone loss, while others will experience significant bone loss over time.

Compared with denser bones, bone loss in low-density bones is more significant. Since the buccal/facial bones of the two arches are less dense than the tongue plate, the face/buccal side will show more bone loss than the tongue/palatine side. The anterior maxilla (anterior maxilla), especially the area of ​​the central incisor and lateral incisor, is more prone to bone loss after tooth extraction. This is related to the low density of facial bones. Usually, the bones of the teeth and faces are thin, and there may be natural cracks and windows, as well as vestibular depressions related to the skeletal trajectory.

During the period of time that tooth extraction is required, the absorption associated with tooth extraction or even periodontal disease may make the area insufficient to accommodate the implant planned to replace the missing tooth. This will require increasing the width of the ridge in the facial and palatine dimension to provide bone mass through bone grafting and allow implant placement. This situation usually requires a two-stage method. The bone graft is first performed to allow it to heal and mature, and then the implant is implanted when the bone mass is sufficient to maintain the initial stability of the implant during the healing phase. The technique to be described can also be used when there is sufficient ridge width at the top to place the implant, but the fenestration that appears during placement exposes part of the top half of the implant.

A 52-year-old male patient has missing left upper central incisor and lateral incisor, hoping to replace the missing teeth with implants and fix the restoration method. The patient stated that the tooth had been extracted eight years ago, and the clinical examination revealed facial defects and healthy soft tissues in the alveolar ridge at the extraction site (Figure 1). The cone beam CT (CBCT) was photographed and evaluated. The cross-sectional view of the missing tooth gap confirms that the width of the alveolar ridge in the facial and palatal dimension is not large enough to accommodate the adjacent implants (Figure 2). The patient was informed of the clinical findings and needed to discuss expanding the site with a bone graft to implant the implant. Due to insufficient bone mass, the implant cannot be implanted at the same time as the implant, so the patient was told that a healing period of 4 to 6 months is required between implants before implants are implanted. Then it will be four to six months for the implant to be osseointegrated before any restoration can be placed on the implant. The patient agreed to treatment and was appointed.

Figure 1: Resorption after tooth extraction results in facial defects in the anterior maxilla. (Photo courtesy of Dr. Arun K. Garg, Dr. Gregori M. Kurtzman, Dr. Renato Rossi Jr. and Dr. Maria del Pilar Rios) Figure 2: CBCT cross-section shows that the width of the facial palatal ridge is insufficient to allow implantation at the healing extraction site Into the implant. Figure 3: A full-thickness skin flap is made to expose the facial defect of the edentulous anterior maxilla, which will receive enhancements to accommodate implant placement. Figure 4: Use a bur through the cortical bone in the toothless space that will receive the bone graft to open the window to the panel. Figure 5: A vertical release incision is made between the first molar and the second premolar. The incision is located in the area to be turned over where the donor site of the right posterior mandible develops. Figure 6: The alveolar ridge incision is connected to the vertical release incision with a groove incision, and then the full-thickness skin flap is lifted to expose the side of the mandibular body. The mandibular body will serve as the donor collection site. Figure 7: Place the autologous bone collected from the posterolateral side of the mandible using mx-grafter (Maxilon, Hollis, NH) into a sterile mixing tray. Figure 8: The buffy coat of the centrifuged PRP tube was added to a sterile petri dish containing harvested autologous bone and granular graft material. Figure 9: A 15 x 30 mm Flexo-Plate Plus (Osteolife Biomedical, Jupiter, Florida) will be placed as a new facial extension of the ridge to accommodate the graft and serve as the required mold ridge reinforcement. Figure 10: Place the holes through the Flexo-Plate Plus and place the fixing screws to fix it on the left and right sides of the transplant area. Figure 11: The "sticky bone" graft material has been fused into a flexible substance containing the PRP buffy coat, harvested autologous bone, and granular graft material. Figure 12: The PRP autologous granular graft ("glue bone") is placed in the space between the stable Flexo-Plate and the edentulous alveolar ridge. Figure 13: The PRP membrane is placed on the graft area before the flap is closed, as a long-term absorbable membrane to prevent soft tissue from ingrowth as the bone graft heals and matures. Figure 14: Use a 5-0 polypropylene suture (Riverpro, Osteolife Biomedical, Jupiter, Florida) to close the flap without tension in a simple intermittent pattern. Figure 15a: The alveolar ridge of the previous defect of the left central incisor and lateral incisor due to the absorption of the previously extracted tooth has been strengthened, and the implant is ready to be implanted 4.5 months after the graft has healed. Figure 15b: The alveolar ridge of the previous defect of the left central incisor and lateral incisor due to the absorption of the previously extracted tooth has been strengthened, and the implant is ready to be implanted 4.5 months after the graft has healed. Figure 16: The CBCT cross-section of the face of edentulous alveolar ridge transplantation shows that the graft has enough width for implant placement after 4.5 months of healing. Figure 17: The graft ridge that healed 4.5 months after flap elevation showed sufficient face and palate width to allow implant placement. Figure 18: The implant has been placed in the previously defective graft alveolar ridge, showing enough bone to accommodate the implant, and the face is not cracked, shown before the valve is closed. Figure 19: The CBCT cross-section after implant placement proves that it is wide enough to accommodate the implant and sufficient panel thickness. Arun K. Garg, DMD Gregori M. Kurtzman, DDS Renato Rossi Jr., DMD, MSc, PhD Maria del Pilar Rios, DMD, MSc, PhD

The patient went to the first stage of treatment, which was to increase the alveolar ridge through lateral transplantation. After review, the patient signed a written consent. Blood was drawn from the patient's left elbow fossa to fill four glass tubes (Becton, Dickinson and Co., Franklin Lakes, NJ) for the preparation of the latest 2018 variant of raw platelet-rich plasma (PRP). Place the two tubes in a PRP centrifuge (MedEquip Dental Supplies, Jupiter, Florida) and spin at 3,500 rpm for three minutes. The short centrifugation time will not completely coagulate the blood in the tube, but it will pre-coagulate the blood. While centrifuging the blood, local anesthetic was infiltrated in the edentulous area of ​​the maxillofacial region and the right posterior buccal side, and an IAN block was performed on the lower right. Place the two tubes in a separate centrifuge and centrifuge at 1,500 rpm for 12 minutes.

Use a #15 scalpel to create a vertical release incision between the right canine and lateral incisor and between the first and second premolars on the left. These are connected through the inner side of the facial groove incision to the vertical release incision and the mid-ridge incision in the edentulous zone. The full-thickness skin flap is raised and extended across the muco-gingival junction to expose the defect area and the bone covering the root of the adjacent tooth (Figure 3). Confirm that there is a thin ridge with significant concavity in the missing tooth area that is related to the content visited in the CBCT examination. Three-sided 1.2 mm burs from MedEquip Dental Supplies are used in surgical handpieces to create multiple skinning points, passing through the cortical bone to the cancellous bone below (Figure 4). This is done to allow endosteal osteoblasts from cancellous bone to interact with the graft, grow bone around and inside the granular graft particles, and accelerate the vascularization and incorporation of the graft into the bone bed.

Next, the donation site will be processed. Use a #15 scalpel blade to create a vertical release incision between the right mandibular first molar and second premolar (Figure 5). Make a buccal groove incision on the first and second molars, and continue the alveolar ridge incision on the buccal side of the midline of the alveolar ridge, and lift the full-thickness flap to expose the side of the mandible (Figure 6). Use mx-grafter (Maxilon, Hollis, NH) to scrape the exposed bone at the oblique ridge to collect the autogenous bone, incorporate it into the graft, and place it in the maxillary anterior teeth. Place the collected bones in a sterile dish (Figure 7). Add 100-850 micron diameter cortical cancellous particle graft material (Osteolife Biomedical) to a sterile petri dish to increase the volume of the graft. With the previously centrifuged blood collected at the beginning of the appointment, the buffy coat part (middle layer) is withdrawn from the tube and placed in a sterile dish together with the harvested autologous bone and granular graft (Figure 8). After stirring the mixture, let it stand for 10 to 15 minutes to complete the solidification stage. The buffy coat of PRP contains high levels of platelets, which will act as a glue to hold the graft in a flexible mass and prevent displacement during the initial healing process. In addition, plasma contains high levels of platelet-derived growth factor (PDGF-AB), transforming growth factor (TGF-beta1), and cytokines that can affect inflammation, angiogenesis, stem cell migration, and cell proliferation. The skin flap at the donor site was repositioned and closed with 4-0 interrupted PLA absorbable sutures (Violet, Osteolife Biomedical, Jupiter, Florida) to achieve a preliminary closure.

A 2 mm thick Flexo-Plate Plus (Osteolife Biomedical) measuring 15 x 30 mm is inspected at this site to ensure adequate coverage of the defect and extension beyond its lateral boundary (Figure 9). Flexo-Plate Plus is a bendable, partially decalcified allograft with a thickness of 0.75 to 1.0 mm. The bone matrix that makes up the Flexo-Plate will eventually be absorbed by the body without surgery to remove the matrix. This will help stabilize the implant implanted in the facial defect and become a new facial cortex after healing. The steel plate is pre-drilled with holes through the steel plate on the left and right sides to accommodate the fixing screws. Flexo-Plate Plus is soaked in salt water to make it flexible and easier to adapt to the curvature of the spine. This applies to dental arches and is fixed with a single titanium screw at the distal end of the left canine and the distal right of the right central incisor (MedEquip Dental Supplies, Jupiter, FL) (Figure 10). The transplanted mixture of PRP, autologous bone debris and granular grafts is fused in a sterile dish into a soft substance with the consistency of a gumdrop and is called "gummy candy" (Figure 11). This is done in the oral cavity and filled between the perforated panel and the stable Flexo-Plate to create a new ridge width dimension when the healing is complete (Figure 12). The graft and Flexo-Plate are covered with a PRP membrane (also called PRF by some authors), which will act as a short-term barrier to prevent soft tissue ingrowth and a source of growth factors when the graft heals and matures (Figure 13). The flap was refitted in a tension-free manner, and the edges were secured in a discontinuous pattern with 5-0 polypropylene sutures (Figure 14). Post-operative instructions were given, and a booklet containing instructions was provided to the patient. [1] These instructions include applying ice packs to the affected area for 20 minutes and 20 minutes for two to four hours to help prevent excessive swelling and discomfort; avoiding hot liquids and food for the first 24 hours after surgery, and then Rinse with warm salt water four to five times a day for the next week. The patient was prescribed 24 tablets of Vicodin (5 mg hydrocodone bitartrate/30 mg acetaminophen) and was instructed to take one tablet every six hours to relieve pain. A prescription for Medrol dosage packs is also provided, and patients are instructed to follow the recommended packs.

The patient returned two weeks later for suture removal and site healing assessment. Both the donor and recipient flaps remain similar. No gaps were found at the incision, and there was no inflammation during the healing process. The patient reported that he was comfortable and was instructed to continue washing with warm saline for a week to help the extra soft tissue heal.

4.5 months after the operation, the patient returned, the soft tissue above and near the site was free of inflammation and looked healthy, and the transplant site felt dense on palpation (Figure 15a, b). CBCT was used to assess the maturity of the graft and the change in spine width after transplantation. The CBCT cross-section of the graft shows the dimensional changes of the joint of the graft and the width of the alveolar ridge, and the implant can now be placed (Figure 16). Local anesthetic (2% lidocaine and 1:100,000 epinephrine) is applied to the site by infiltration and raises the full-thickness flap. The graft is indistinguishable from the adjacent non-grafted bone, and the device looks dense when it touches, and the defect is filled to provide enough width for the implant placement (Figure 17). Osteotomy is used to place a 3.7 mm x 13 mm implant (ImplantVision, West Palm Beach, Florida) on the central left side, place a 3.2 x 13 mm implant on the left side, and place the implant and connect it Cover screws (Figure 18). The site was sutured with a 5-0 polypropylene suture in a discontinuous pattern, and the patient left. The repair of the implant will be carried out after an integration period of three to five months. CBCT performed after implant placement showed that the facial bones of the implant were thick enough to accommodate the implant and allow long-term stability (Figure 19).

The common case of maxillary anterior tooth loss is the missing faceplate, resulting in bone size that cannot accommodate implant placement. When tooth pulp, periodontal or structural (vertical root fracture) changes occur, panel absorption may occur during tooth extraction. This is usually complicated by natural cracks and fenestrations on healthy teeth, which can worsen when pathology occurs.

Various treatment options have been proposed to reconstruct the defective anterior maxilla. These include the use of cortical masses taken from another site (branch, iliac crest) and fixed with screws during the healing process. Titanium mesh has been proposed for cage graft material, allowing the reconstruction of the ridge. Spinal split is another recommended treatment to create a ridge that can accommodate implant placement. These methods have a negative impact on their use. Cortical block requires a donor site, which increases morbidity during the healing phase and reduces patient comfort. In addition, if the block is not integrated with the recipient bed, it may cause separation at the time of implantation or when the function is restored. Some healing reabsorption has been reported, and overbuilding the site can be considered to accommodate the loss of volume during the healing process. [2] The use of titanium mesh requires a second operation to remove the metal mesh and screws, which is done when the implant is ready to be placed in the healing site. But the main reported use complication is the premature exposure of the grid. [3] This may require early removal of the mesh, thereby reducing the quality and quantity of bone produced by the graft surrounded by the mesh. [4] Even though complications are usually encountered during the healing phase, the implantation success rate in the area where the titanium mesh is used for transplantation does show a high success rate. [5]

The use of spine splitting has been advocated to treat narrow ridges, but a minimum ridge width is required to effectively split it. Absorption occurs in the vertical dimension, but will lose less dense panels. When the ridge is split, the density of the palatine bone expands in the direction of the face. If the alveolar ridge loses significant facial bone structure, it cannot be expanded. It is reported that when the initial alveolar ridge width is sufficient, the alveolar ridge split will have minor complications, including wound dehiscence and panel fracture due to poor splitting. However, the incidence of complications is the same as that of blocking the transplant site. [6]

The technique illustrated in the case presented here is an alternative method that eliminates the need for cortical bone from the donor site and reduces the complications of using titanium mesh to contain the graft. In addition, the width of the residual ridge does not determine whether this technique can be used to limit ridge splitting. Since a bone scraper is used to remove cortical fragments from the patient and mix with PRP from the patient's own blood, the possibility of foreign body reactions is minimized. The stem cells from the patient can "initiate" healing and transform into bone of high enough quality to be suitable for implant placement after the graft has healed. Ideally, the implant should be placed in the medullary bone that is in contact with most of the surface because the bone is dynamic and active. Cortical bone is denser, but lacks osteoblasts and other bone-maintaining cells, which may show radiographically dense bone in contact with the implant, but also fails to respond to changes related to the function of the implant. With the flexible bone plate (Flexo-plate plus) provided by the supplier, there is no need for titanium mesh to accommodate the graft, and it becomes a part of the healing graft like a cortical block. The additional benefit of this technique over cortical blocks is that the bone used for implant implantation has a medullary quality, and the implant has active bone progenitor cells in contact with the surface of the implant. Unlike titanium mesh, the risk of bone plate exposure is eliminated because the body does not recognize the bone plate as a foreign body. The covered PRP membrane stimulates soft tissue healing, where the stem cells penetrate into the bone plate, use it as a scaffold, and transform it into host bone over time. The cohesive bone sandwiched between the Flexo-plate plus and the receptor bed has an additional advantage over the pellets, that is, it is plastic and does not move out of the site like the pellets are often observed.

Rebuilding the shrunken maxilla to accommodate implant placement can be challenging, and this is related to the lack of bone to accommodate the implant. Various techniques have been reported to reconstruct the defective area. The technique described here eliminates some of the potential complications associated with other reported techniques and provides high-quality bone suitable for implant placement.

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