Segmental osteotomy for mobilization of dental implant
The patient, a 38-year-old female, visited the Oral Implantology Unit in conjunction with the Oral Rehabilitation Unit of the Universidad de La Frontera for problems she had detected in the installation of a singular fixed prosthesis in implants that had previously been installed by other professionals.\nThe clinical examination revealed a mesomorphic patient, facially proportionate, with no prior alterations or surgeries at the facial level. A slight vertical excess of the maxilla (approximately 3 mm) was observed, coinciding with a high smile level and greater tooth exposure with the lips at rest.\nThe intraoral examination showed partial edentulism, alterations in occlusal balance, diastemas with poor tooth positions, and the position of two implants in 11 and 21 (3.75 mm×13 mm) with their respective healing abutments. Both implants were found with the emergence in a more anterior position than appropriate, but implant 11 was found with high (3 mm over the ideal) and anterior emergence, suggesting an angulation greater than 30° (). The radiographic study revealed stability of the implants with no signs of peri-implantitis or alterations in the osseointegration ().\nAfter studying some treatment options, it was determined that a segmental osteotomy of implant 11 should be performed for inferior and posterior repositioning, placing it closer to the position and angulation of implant 21. In the study model, the model surgery was conducted that would make it possible to define the inferior repositioning as having to be at least 3 mm and the anterior displacement in the upper sector as having to be 2 mm using the middle area of the implant as the rotation axis that allowed the cervical sector to perform a 2 mm movement posteriorly ().\nThe procedure was performed under local anesthesia with 8 mL of lidocaine with 2% epinephrine, 1:100.000, in the vestibular and palatal sector.\nA 2-mm linear incision was made on the mucogingival border 3 cm long (), a total subperiosteal detachment of the vestibular region was performed, and the implant area was completely exposed from the cervical to the lower edge of the piriform aperture.\nAfter identifying the entire extension of the implant, the horizontal osteotomy was conducted 5 mm above the edge of the implant and vertical osteotomies in the medial and lateral sectors with a 5-mm safety margin (). The osteotomies went from the vestibular cortical to the palatal cortical layer. For this, a 701 drill mounted on a low-speed (20,000 rpm) handpiece was used. The osteotomy was completed with a straight chisel and the block was mobilized, keeping it adhered to the palatal periosteum to ensure the blood supply of the mobilized block.\nLater, a bone block of the mandibular ramus was obtained (), extracted using a conventional technique [] that allowed the insertion of this block into the upper sector of the mobilized block to stabilize the sector, permitting stabilization of the planned 3-mm descent. The remaining autogenous bone was crushed and served to fill the spaces from the osteotomy and defects caused by the procedure (). Given the overall stability of the block, another type of fixation system was unnecessary. The suture was made on a plane with simple 3-0 Vycril stitches. The emergence of the implant that would allow prosthetic rehabilitation was confirmed intraoperatively ().\nAfter 4 months of follow-up, new radiographs were taken, identifying the total repair of the bone tissue and the stability of the installed implant. No complications associated with the procedure were observed. The conventional rehabilitation techniques for implants were then used, with tailor-made casting abutments with a chromium-cobalt machined base, and the angulation and desired form of the abutment were attained to make cemented metal ceramic crowns (); Ketac Cem permanent glass ionomer cement was used for this (3M ESPE Dental Product, St. Paul, MN, USA).