Full-staged digital and prosthetic guided protocol for the insertion of dental implants in autogenous free bone grafts after reconstruction of segmental mandibular defects

PURPOSE

This study aims to evaluate the clinical and radiographic outcomes of dental implants, inserted in consolidated free bone grafts; postsegmental mandibular resection, after following a fully guided staged protocol, which established a systematic approach that correlates the grafted bone and the enclosed implants to the undisturbed mandibular segments and the maxillary occlusal plane.

METHODS

Seven patients were enrolled in the study; all were diagnosed for mandibular locally aggressive tumors. All of the patients were subjected to computer-guided segmental mandibular resections, secondary free iliac crest bone graft; aided by computer-guided harvest and prosthetic guidance of the graft positioning and fixation. Finally, the guided bone grafts; after being consolidated, received twenty-nine computer-guided dental implants.

RESULTS

By the end of the period of osseointegration, the predetermined criteria of implant success judged the success of twenty-five implants, versus the failure of four implants, with (86.2%) percentage of success.

CONCLUSION

The clinical and radiographic assessments demonstrated sound base bone grafts, which succeeded not only to restore the native mandibular continuity and configuration but also to direct the fair-sized embedded dental implants into favorable coastal locations and axial projections, which influenced a smooth prosthetic rehabilitation.

Simultaneous Le Fort I osteotomy and computer-guided implant placement

BACKGROUND

Since 1977, osseointegrated implants have played a strong role in oral rehabilitation. Despite the large success of this technique for the edentulous maxilla and mandible with sufficient bone height, patients with atrophic jaws continue to be the challenging cases for an adequate reconstruction of aesthetics and functionality. Orthognathic surgical procedures have been developed to reposition the jaws and have been traditionally used in the dentate patient to correct a skeletal malocclusion; these procedures can be used on the edentulous patient to correct the discrepancies between the jaws followed by the placement of implants to rehabilitate the oral cavity. Recently, surgeons can use a computer-assisted software package that enables them to insert implants after a digital analysis of the residual alveolar and basal bone that makes for greater implant osseointegration. We describe a one-step oral rehabilitation with Le Fort I osteotomy and computer-guided implant placement to correct a posttraumatic deformity.

CLINICAL REPORT

The first step of the definitive treatment, the implant placement, was planned with the aid of a computer-assisted surgery software package (NobelGuide; Nobel Biocare AB, Goteborg, Sweden). Ten computer-planned implants (Nobel Biocare AB) were inserted (6 on the maxillary arch and 2 on each posterior area of the mandible). Simultaneously, the patient underwent a Le Fort I osteotomy to correct the maxillary deficiency without any bone grafts.

DISCUSSION

The use of Le Fort I osteotomy as a preprosthetic procedure for the atrophic edentulous maxilla has been well accepted. This is a technically demanding procedure, and there are some described complications such as unfavorable fractures of the maxilla, oroantral fistulas, bone exposure, and low implant survival rates. However, in selected cases, this reconstructive method has the advantages over the other commonly used preprosthetic techniques of simultaneously allowing the placement of osseointegrated implants while correcting an unfavorable intermaxillary relationship and improving facial aesthetics. Computer-assisted surgery offers to the surgeons the possibility to visualize anatomic structures, evaluate implant position and inclination, insert accurately implants, prefabricate prosthesis, and avoid the morbidity of bone grafting procedures.

CONCLUSIONS

One-step oral rehabilitation by Le Fort I and computer-guided implant placement can be used in selected patients. Despite the difficulty of this procedure, this approach enabled the authors to solve simultaneously a double problem: the malocclusion and the partially atrophic and edentulous jaws. According to the literature, this is the first case of a simultaneous Le Fort I osteotomy and computer-guided implant placement. The patient introduced had a posttraumatic deformity, but we think that this procedure could be extended in the future to manage other situations.

Computer-Assisted Surgery in the Lower Jaw: Double Surgical Guide for Immediately Loaded Implants in Postextractive Sites—Technical Notes and a Case Report

Computer-assisted surgery is based on computerized tomography (CT) scan technology to plan the placement of dental implants and a computer-aided design/computer-aided manufacturing (CAD-CAM) technology to create a custom surgical template. It provides guidance for insertion implants after analysis of existing alveolar bone and planning of implant position, which can be immediately loaded, therefore achieving esthetic and functional results in a surgical stage. The absence of guidelines to treat dentulous areas is often due to a lack of computer-assisted surgery. The authors have attempted to use this surgical methodology to replace residual teeth with an immediate implantoprosthetic restoration. The aim of this case report is to show the possibility of treating a dentulous patient by applying a computer-assisted surgical protocol associated with the use of a double surgical template: one before extraction and a second one after extraction of selected teeth.