Clinical and radiographic assessment of patient-specific transantral reconstruction of orbital floor fractures: A case series.

To clinically and radiographically evaluate patient-specific titanium meshes via a trans-antral approach for correction of enophthalmos and orbital volume in patients with recent unilateral orbital floor fracture. Seven patients with unilateral orbital floor fractures received patient-specific titanium meshes that were designed based on a mirror-image of the contralateral intact orbit. The patient-specific implants (PSIs) were inserted via a trans-antral approach without endoscopic assistance. The patients were evaluated clinically for signs of diplopia and restricted gaze as well as radiographically for enophthalmos and orbital volume correction. Diplopia was totally resolved in two of the three patients who reported diplopia in the upward gaze. Whereas enophthalmos significantly improved in all but two patients, with a mean value of 0.2229 mm postoperatively compared to 0.9914 mm preoperatively. CT scans showed excellent adaptation of the PSIs to the orbital floor with a mean reduction of the orbital volume from 29.59 cc to 27.21 cc, a mean of 0.6% smaller than the intact orbit. It can be concluded that the proposed PSI can offer good reconstruction of the orbital floor through an isolated intraoral transantral approach with minimal complications. It could of special benefit in extensive orbital floor fractures.

Guided Bone Regeneration for Horizontal Maxillary Alveolar Ridge Augmentation Using Patient-Specific Solid Titanium Barriers: A Case Series

PURPOSE: To assess the radiographic and histomorphometric outcomes of horizontally augmented maxillary alveolar ridges using solid nonperforated customized titanium barriers. MATERIALS AND METHODS: This case series study included patients who received guided bone regeneration treatment in the anterior maxillary esthetic zone (eight patients, 18 dental implants) using patient-specific solid titanium barriers loaded with a mix of autogenous and xenogenic particulate bone grafts. A radiographic comparison between three time periods (immediately postoperative, 4 months, and 10 months) included software-aided calibration of the linear changes in the horizontal dimensions on CBCT cross-sectional cuts after being standardized. Bone core specimens were retrieved for histomorphometric analysis by the time of implant insertion. RESULTS: Wound healing was uneventful, except for two patients who showed soft tissue breakdown that did not affect the outcome. There was a statistically significant difference between the mean horizontal bone change at the different time intervals (P < .001), with a 79.6% ± 29.2% mean area of newly formed bone. CONCLUSION: GBR using customized solid titanium barriers appears to be efficient and promising concerning the final horizontal bone gain and the quality of the augmented sites.

Patient-specific alloplastic endoprosthesis for reconstruction of the mandible following segmental resection: A case series.

Reconstruction of mandibular discontinuity defects remains a challenge for maxillofacial surgeons. Despite vascularized free flaps representing the current gold standard for managing such defects, the search continues for other less morbid yet predictable interventions. This study aimed at reviving the idea of alloplastic mandibular endoprosthesis as a treatment modality for reconstruction of segmental mandibular defects following eradication of benign tumors. To reconstruct their segmental mandibular defects, this case series compiled seven patients who received patient-specific titanium implant (PSI) with osseointegrated components and were designed to receive a restoration for dental rehabilitation. The recruited patient population was followed-up for a period of 3-5 years. Three of the seven PSIs failed due to extensive intraoral mucosal dehiscence or persistent extraoral fistulae. Patients with the 4 surviving PSIs enjoyed good results in terms of occlusion, masticatory function, mouth opening as well as pleasing facial esthetics. The described technique represents a viable less morbid alternative to the standard bone grafting techniques for mandibular reconstruction in carefully selected patients. Further studies are needed to modify the PSI design and surface treatment for better outcomes.

Quality of life after different approaches of orthognathic surgery: a randomized controlled study.

BACKGROUND: Over the last decade, the accuracy of 3D computer-assisted orthognathic surgery has been extensively investigated. However, patient-reported outcome measures have been rarely reported for this technology. This study aimed to assess quality of life following orthognathic surgery using CAD/CAM bone splints compared to the classic occlusal wafers in patients with dentofacial deformities. METHODS: Thirty-two patients were randomly allocated into two groups where group I utilized CAD/CAM splints and patient specific osteosynthesis for maxillary positioning and group II utilized occlusal wafers fabricated on a semi-adjustable articulator. Patients were assessed using orthognathic quality of life Questionnaire (OQLQ) preoperatively and 6 months postoperatively. RESULTS: Mean OQLQ overall score change of 24.375±11.96 took place in group I patients while group II showed a mean change of 23±8.39. CONCLUSIONS: The study showed evident improvement in quality of life following orthognathic surgery compared to before surgery. However, computer-assisted surgery did not show any significant improvement over the classic approach.

Assessment of vertical ridge augmentation and labial prominence using buccal versus palatal approaches for maxillary segmental sandwich osteotomy (inlay technique): A randomized clinical trial.

BACKGROUND: The aim of this study was to evaluate the final vertical gain at the deficient anterior maxillary alveolar ridges using buccal versus palatal approaches for maxillary segmental sandwich osteotomy (inlay technique). This is a single-institutional randomized comparative clinical trial. MATERIAL AND METHODS: The study population was 16 patients with edentulous anterior maxillary alveolar ridges (40 implant sites). Patients were randomly divided into two equal groups. Both groups received sandwich osteotomy with down fracture of the deficient anterior maxillary alveolar ridge, using buccal approach (control group) and palatal approach (study group) with interpositional alloplastic bone blocks fixed with miniplates. Assessment included the mean percentage of vertical gain at the proposed implant sites after 4 months, taken from cross-sectional cuts of a cone beam computed tomography. RESULTS: All cases showed uneventful wound healing and a total of 40 delayed implant placement were done. Results showed that there was no statistical significance between the 2 groups in terms of bone height (P = .43) and labial prominence (P = .5) CONCLUSION: Both techniques were successful where the mean percentage of 4 months postoperative vertical bone gain of the control group was 79.9% and that of the study group was 76.5%.

Clinical and radiographic evaluation of a computer-generated guiding device in bilateral sagittal split osteotomies.

The bilateral sagittal split osteotomy (BSSO) is one of the main orthognathic surgery procedures used for managing skeletal mandibular excess, deficiency or asymmetry. It is known to be a technique-sensitive procedure with high reported incidences of inferior alveolar nerve injury, bad splits and post-surgical relapse. With the increasing use of computer-assisted techniques in orthognathic surgery, the accurate transfer of the virtual plan to the operating room is currently a subject of research. This study evaluated the efficacy of computer-generated device at maintaining the planned condylar position and minimizing inferior alveolar nerve injury during BSSO. The device was used in 6 patients who required isolated mandibular surgery for correction of their skeletal deformities. Clinical evaluation showed good recovery of the maximal incisal opening and a reproducible occlusion in 5 of the 6 patients. Radiographic evaluation showed better control of the condyle position in both the vertical and anteroposterior directions than in the mediolateral direction. The degree of accuracy between the planned and achieved screw positions were judged as good to excellent in all cases. Within the limitations of this study and the small sample size, the proposed device design allowed for good transfer of the virtual surgical plan to the operating room.

Nongrafted sinus floor elevation with a space-maintaining titanium mesh: case-series study on four patients.

PURPOSE: Numerous materials and techniques have been introduced to augment the maxillary sinus floor for future dental implant placement. Schneiderian membrane tenting above simultaneously placed implants proved to be a successful technique. The present study investigated the use of a titanium micromesh for lateral-window sinus floor elevation without bone grafting. MATERIAL AND METHODS: Four patients indicated for two-stage sinus lifting were included. Through a lateral window, a titanium micromesh was tailored and placed into the sinus to maintain the elevated membrane in place. Immediate and 6-month postoperative cone beam computed tomography (CBCT) was performed to measure the gained bone height. During implant placement, bone core biopsies were retrieved for histomorphometry. RESULTS: The average residual ridge height among the eight sinuses was 3.6 mm ± 1.6 mm. Six months postoperatively, it reached 9.63 mm ± 1.47 mm. Histomorphometry revealed that the average bone volume of the native bone was 30.3% ± 9.1%, while that of the newly formed bone was 55.3% ± 11.4%. CONCLUSION: Within the limitations of this study due to the small sample size, the use of the titanium micromesh as a space-maintaining device after schneiderian membrane elevation is a reliable technique to elevate the floor of the sinus without grafting.

Computer-guided rapid-prototyped templates for segmental mandibular osteotomies: a preliminary report.

BACKGROUND: Segmental mandibular resection represents a challenge to maxillofacial surgeons in terms of accurate contouring of reconstruction plates, restoration of mandibular symmetry and maintaining accurate condylar position in the glenoid fossae. METHODS: We propose a CAD/CAM technique for fabricating patient-specific templates to symmetrically prebend reconstruction plates, guide osteotomies and reposition the condylar process in the proximal edentulous segment in its preoperative position. We operated on two patients using this new technique. RESULTS: The custom-made templates showed excellent passive fit on the respective mandibles and accurately guided the reciprocating saw blade along the resection margins. The template was also capable of maintaining the spatial relation of the resected mandibles and the patients experienced excellent repeatable occlusion. Superimposition of pre- and postoperative cone-beam CT scans showed restoration of mandibular symmetry and maximum deviation of 0.4-1.4 (mean of 0.9) mm from the preoperative condylar position. The achieved resection margins using the template showed a mean distance of 1.17 mm from the virtually planned ones. CONCLUSION: We present an innovative computer-guided template that allowed for accurate guidance of mandibular resection margins and condylar positioning. The technique needs to be applied in a larger cohort of patients to verify the results. Further modifications of the design and rigidity of the template might proof beneficial.