Introduction
The Le Fort fractures originally described by Rene Le Fort in 1901 are specific types of facial bone fractures that result from blunt face trauma (most often from motor vehicle collisions, assaults, or falls.1 The pterygoid processes of the sphenoid bones are involved in all Le Fort fracture types, which alters the intrinsic buttress system to the midface. The classification of Le Fort types I, II, and III relies on examining how the maxillary, nasal, and zygomatic bones are impacted. Depending on the extent of involvement of these specific facial bones, a particular Le Fort type can be identified.
In the maxillary anterior region, using dental implants to replace missing teeth is a viable treatment option. 2 Compared to traditional crown and bridge or removable tooth-borne prosthetics, fixed dental implant-supported prostheses offer several benefits. These include the maintenance of residual bone, ease of oral hygiene, increased longevity, and the avoidance of complications with adjacent teeth. In the anterior maxillary zone, the aesthetic success of implant therapy is just as important as the survival rates of the implants. 1Patients now expect restorations that are both functional and aesthetically pleasing. The current definition of success in implant therapy includes not only long-term predictability, function, and integration of the implant but also aesthetic considerations. 2, 3 However, placing implants in the anterior maxilla can be challenging especially when the dentoalveolar fracture is involved due to trauma-induced bone resorption and the presence of a thin buccal cortical plate, flare of the premaxilla, higher rate of resorption, and low density of bone. Osseous grafting can be performed for ridge widening; however, it may not facilitate the vertical placement of implants or maintain the natural bone contours. 4
A thin buccal cortical plate of the maxilla often leads to the implant being placed more palatally, resulting in excessive angulation about the long axis of the adjacent tooth. This presents enormous challenges in prosthetic rehabilitation of the anterior aesthetic region. 5
One of the solutions for such cases of off-axis implant placement, but this can further complicate mechanical considerations and the patient’s force factor which can be compensated for by using angled abutments and implant-protected occlusion. However, the angle compensation must be greater than 17 degrees for these angled abutments to be used. This is necessary to ensure sufficient divergence in the trajectory of the abutment screw, allowing for proper housing of the retentive screw of the restoration. If the divergence between the implant axis and the retaining screw of the abutment is less than 17 degrees, there will not be enough bulk to support the restoration. In this case, cement-retained prosthesis can be a treatment option. 6
The present case report outlines the successful management of complex Lefort and dentoalveolar fracture and prosthetic rehabilitation by positioning nonaxial implants within the anterior maxillary region, as well as the effective resolution of aesthetic complications by using customized abutments at the same time justifying the force factor and maintenance of occlusal harmony. Since the longevity of the prosthesis is determined by occlusal harmony, occlusion is the most important aspect to be dealt with during oral rehabilitation. 7
Case Description
A 19-year-old male patient reported to the Department of Oral and Maxillofacial Surgery, K.V.G Dental College, Sullia, Karnataka, with the chief complaint of missing upper front teeth due to a road traffic accident. The patient presented a history of trauma due to a road accident. The clinical signs and symptoms were swelling of the midface, profuse nasopharyngeal bleeding, pain associated with the upper lip and cheek, malocclusion, and intraoral lacerations. CECT was done which revealed a fracture of both the zygomatic buttresses along the inferior portion of the piriform apertures along with a dentoalveolar fracture which indicated Le- fort 1 fracture (Figure 1). Prophylactic systemic antibiotics and anti-inflammatory drugs were administered. The patient was recalled after 7 days for the surgery.
After the swelling resolved, hemodynamic assessment was done and vitals were checked after a week. The patient’s report was normal and the systemic condition allowed surgery. The aseptic environment was assured for the surgery. A gingivobuccal sulcus incision was used to access Le Fort I fractures, then was fixed by re-establishing the midfacial buttresses with 1.5 to 2.0 mm L and J plates. It is important to align the plates with the mastication forces to avoid the forces of mastication interfering with the repair.5 Open reduction and internal fixation, with mini-plates and screws, were performed. Simultaneously, intermaxillary fixation was done. The patient was restricted to having only a soft diet for 2 weeks. A postoperative radiograph was taken which revealed successful reduction and fixation of fracture. Intermaxillary fixation was removed after and diet modification was done. The patient was recalled after 2 months, revealing no pain or tenderness in the fracture site. A detailed intraoral examination was done, which revealed loss of 11, 12, 21 and 22 (Figure 2).
On palpation of the dentoalveolar plate, mild tenderness was noted. CBCT examination was performed to examine the density, width, height, and contour of available bone. Bone availability in region 11 was 5.53mm at the apical third of the root, so ideally, implant size of diameter 3.6 and length 12mm was selected. In region 12, bone width at the apical third was 5.66 mm so an implant size was 3.36x14mm was selected. Region 22 had 5.53mm of bone width at the apical third of the root, an implant of size 3.6 x 12 mm was selected 9 (Figure 3).
Region 21 had inadequate bone available for implant placement because of the proximity of the fracture line, so placement of 3 implants was planned, and prosthetic rehabilitation with FP – 2 was planned by taking the support of 3 implants (Figure 4). According to Misch, FP 2 is a treatment option that replaces missing anatomical crowns and a root portion of the edentulous site, masked using gingival porcelain.
Following these assessments, the patient was presented with various treatment options and after discussing the advantages and disadvantages of each option, they agreed to proceed with implant placement in the area where teeth were missing. To evaluate the space available for prosthetic rehabilitation, the impression of both upper and lower arch was made. Casts were poured and mounted on an articulator using bite registration. The diagnostic wax-up was performed to evaluate mesiodistal width and interarch space available for prosthetic rehabilitation. The patient was presented with this wax mock-up, which he seemed to be very satisfied with in terms of his desired aesthetic appearance. As a result, we moved ahead with the proposed plan for a prosthetic rehabilitation plan.
After evaluating the type and density of bone distribution, two-stage surgery for implant placement was planned to ensure optimal osseointegration after an adequate healing period. Based on the distribution of bone, in Region 11 - an implant of size 3.6 x 12 mm, region 12 - an implant of size 3.36 x 14mm Region 22 an implant of size 3.6 x 12 mm was selected (DENTIUM IMPLANT SYSTEM was used). Off-axis implant placement was chosen due to the thin buccal cortical plate. Consequently, the plan included restoration with customized abutments and a cement-retained prosthesis.
Treatment procedure
The patient reported back to the Department of Oral and Maxillofacial Surgery after 2 months and re-examined for pain or tenderness which revealed no pain. A vitality test of teeth was done, depicting that all the teeth were vital. An anesthetic agent consisting of 2% lidocaine with a 1:80,000 ratio was administered to provide pain relief. Nasopalatine and infraorbital nerve blocks were performed, along with local infiltration in the anterior maxillary region.
A crestal incision was made followed by a crevicular incision, the periosteal flap was elevated and the surgical site was adequately exposed. Bone buccolingual width and mesiodistal length were clinically evaluated for the chosen implant size. After ensuring the adequacy of bone width and length, osteotomy was performed. 3 root form, threaded, rough surface implants (DENTIUM) were then placed and primary stability of 35 N torque was achieved, and cover screws were placed and sutured (Figure 5, Figure 6). Periosteal flap was approximated and sutured. An immediate post-surgical radiograph (OPG) was taken (Figure 7).
The patient was recalled post-surgically after 1 week for follow up and no untoward sign or symptom was noted. Four months after implant placement, the patient was recalled, and a radiograph was taken to examine osseointegration and peri-implant bone condition. There was no marginal bone loss, all the 3 implants showed no signs and symptoms of peri-implantitis or peri-implant mucositis, and delayed stability was present. The gingival covering implant was also healthy. The cover screws were removed and the healing abutments were placed.
After 15 days, there was formation of the gingival collar, and impression copings were attached to the implants (Figure 8) and were splinted together using pattern resin and floss. An open-tray impression technique was used to record the position of the implant. Polyvinyl siloxane putty impression material and light body impression material were used for making the impression, and after the material had set, the impression was snapped out from the mouth after unscrewing the impression coping and replaced with healing abutments.
The impression along with the copings was forwarded to the laboratory to create a custom abutment using UCLA abutment. After the fabrication, custom abutments were seated onto the implant (Figure 9) and a radiograph was taken to verify the complete seating of abutments.
The Jig trial was done and sent to the lab for prosthesis fabrication. Metal try-in (Figure 10) and bite registration were done at the same appointment, then the bisque trial was performed.
Figure 1
Preoperative CECT scan showing Le Fort I fracture involving zygomatic buttresses and dentoalveolar region due to trauma.
Figure 2
Intraoral examination after 2 months, revealing loss of teeth 11, 12, 21, and 22 post-trauma.
Figure 4
CBCT images showing detailed measurements of bone width at the apical third of the root in the areas planned for implant placement.
Figure 7
Post operative follow-up radiograph after 4 months showing successful osseointegration and stable peri-implant bone condition.
Figure 13
Final post operative frontal view showing the cemented prosthesis and surrounding bone structure.
Figure 14
Post operative occlusal images of the patient showing the aesthetic outcome and thepatient’s satisfaction with the rehabilitation
Figure 15
Post operative smilling images of the patient showing the aesthetic outcome and the patient’s satisfaction with the rehabilitation.
Finally, a cement-retained Porcelain fused metal prosthesis (FP-2) was fabricated. The prosthesis was then tried in the patient’s mouth. The proximal contacts and occlusion were checked. In maximum intercuspation, there was light contact with no contact in protrusive and lateral excursions. The prosthesis was then cemented using luting GIC and the access hole was filled using composite restorative material. Oral hygiene instructions were given to the patient and recalled after 3 months for regular check-ups (Figure 11, Figure 12, Figure 13). The patient was pleased with the rehabilitation provided to him and had no complaints (Figure 14, Figure 15).
Discussion
According to estimates by the World Health Organization, traffic accidents contribute to approximately 25% of global injuries and fatalities, with 90% of deaths occurring in low- and middle-income countries. While industrialized nations have seen a gradual decrease in traffic accidents, the numbers continue to rise alarmingly in low- and middle-income countries in Africa and Asia. Motamedi et al.'s study revealed that mandibular injuries accounted for 72.9%, followed by maxillary (13.9%), zygomatic (13.5%), zygomatic-orbital (24.0%), cranial (2.1%), nasal (2.1%), and frontal (1.6%) regions.8
Regarding maxillary fractures, Le Fort Il constituted 54.6%, Le Fort I 24.2%, Le Fort III 12.1%, and alveolar 9.1%. Various techniques, such as internal fixation, circum-mandibular wire, and close reductions, have been utilized for fracture treatment. The four most common methods of internal skeletal suspension are frontal suspension, circumzygomatic suspension, intraorbital suspension, and circumpalatal suspension.9
Precise treatment planning, surgical techniques, as well as prosthetic care, are necessary when placing dental implants in the maxillary anterior region. A profound understanding of anatomical, biologic, surgical, and prosthetic principles is necessary for implant placement in the aesthetic zone to produce a successful aesthetic outcome and high patient satisfaction. It can be not easy to achieve a harmonious and indistinguishable prosthesis from nearby natural teeth in the aesthetic zone.
Dental implant placement in the aesthetic zone is a delicate process that requires precise technique and minimal margin for error. In this instance, the dental implant was positioned off-axis due to a thin buccal plate.10 Because of the implant's location, it was desirable to provide an angled abutment and cement-retained prosthesis. Screw retained prosthesis couldn’t be planned as it resulted in the placement of a screw hole on the labial surface. The presence of screws on the labial surface compromises the aesthetics of prosthetic rehabilitation. The patient was pleased with the aesthetic outcome. 11, 12
Conclusion
The successful management of complex Lefort and dentoalveolar fracture and prosthetic rehabilitation is possible when through assessment of the patient’s anatomy and availability of bone is performed. According to the available bone, implants can be positioned non-axially, escaping the fracture line and other anatomical vitals within the anterior maxillary region thus satisfying the biomechanical and stress distribution demands. The effective resolution of aesthetic complications can be done by using customized abutments and at the same time maintaining occlusal harmony. It's beneficial to place implants off–axis to avoid injury to certain vital anatomical structures and minimize the need for cumbersome procedures like bone grafting, sinus lift, and nerve repositioning. Since the longevity of the prosthesis is determined by occlusal harmony, occlusion is the most important aspect to be dealt with during oral rehabilitation.
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