Severe skeletal bimaxillary protrusion treated with micro-implants and a self-made four-curvature torquing auxiliary: A case report

BACKGROUND Bimaxillary protrusion is a clinically common dentofacial deformity,particularly among Chinese patients.This kind of malformation can severely affect facial esthetics and,even in mild cases,is difficult to correct without surgery.Unfortunately,many patients abandon treatment because of fear of surgery.Here,we describe a case of severe skeletal bimaxillary protrusion treated with nonsurgical orthodontic treatments,highlighting an alternative treatment option.CASE SUMMARY A 31-year-old woman wished to address a severe protrusion profile(approximately 8 mm overbite)and gummy smile.Cephalometric analysis and superimposition showed a severe skeletal class II pattern with a mandibular retrusion,and proclined and protrusive mandibular incisors.Panoramic radiograph showed a missing mandibular right third molar.A diagnosis of severe bimaxillary dentoalveolar protrusion was made.Taking into account the patient’s fear of orthognathic surgery,she accepted the proposed alternative treatment using micro-implants and a self-made four-curvature torquing auxiliary.The treatment allowed for maximal en masse anterior tooth retraction,proper relocation of incisors,and alleviation of the skeletal class II pattern.Esthetically,the patient’s lip protrusion was significantly decreased as was the overjet(from 10.5 mm to 1.8 mm),and the results remained stable throughout the 2-year followup.CONCLUSION Nonsurgical treatment using micro-implants and a four-curvature torquing auxiliary may benefit severe cases of skeletal bimaxillary protrusion in adults.

Correction of post ankylotic facial asymmetry with bimaxillary distraction osteogenesis—Case report

Facial asymmetry can be acquired or congenital. Patients with facial asymmetry are not always functionally disturbed by the malfunction but are usually very much disturbed by their external appearance. Depending on the degree of asymmetry and deformation, the surgical procedure may vary in complexity and extent. The extent of surgery can range from a genioplasty procedure to bimaxillary osteotomy, concomitant with augmentation surgery, genioplasty and craniofacial implants along with mandibular distraction. In severe cases, the soft tissue structures on the affected side may constitute an incredible resistance to stretching and can make the surgery considerably more difficult and liable to relapse. Here we represent a case of post ankylotic facial asymmetry with occlusal cant which was treated by bimaxillary distraction osteogenesis. Simultaneous mandibular and maxillary distraction corrected the facial asymmetry without disturbing the pre-existing compensated dental occlusion, and so there was no need for prolonged and difficult orthodontic treatment.

Prevalence of Bimaxillary Protrusion: A Systematic Review

Objective: This study aimed to systematically review current relevant literature on the prevalence of bimaxillary protrusion. Materials and Methods: The electronic databases PubMed, Medline, Scopus, Google Scholar and the Cochrane Library were searched using specific inclusion criteria to obtain applicable articles. References from included studies were also examined. Results: Three articles were identified that met the inclusion criteria. Prevalence of bimaxillary protrusion ranged from 3.7% to 68.8% in different populations reported in the literature examined. GRADE assessed overall confidence was deemed to be very low. Conclusion: These results show that the prevalence of bimaxillary protrusion varies greatly between races and geographic regions. The Trinidad and Tobago population has a high prevalence of bimaxillary protrusion.

Extraction treatment of an adult patient with severe bimaxillary dentoalveolar protrusion using microscrew anchorage

Bimaxillary dentoalveolar protrusion is one of the most prevalent malocclusion in Asian population.Traditionally, orthodontic treatment often involves the extraction of four first premolars and demands the least amount of anchorage loss, therefore headgear used to be an unavoid- able fate of these patients. Nowadays, along with the development of implant anchorage, more and more patients have benefited from the implant-aided orthodontic treatment, even escaped from orthognathic surgery. However, for extremely severe cases, orthodontists seem to still have to face the limitation of orthodontic treatment and turn to surgeons for cooperation. In this case, we will see how dramatic changes happened on an adult patient with severe bimaxillary dentoalveolar protrusion malocclusion after the orthodontic treatment with microscrew implants as the temporary skeletal anchorage with the patient＇s written informed consent,

Horizontal Chin Bar

Background: Correction of long face and chin retrusion has a significant effect on facial aesthetic and symmetry. Bimaxillary (Bimax.) Operation has been performed for long face and bimaxillary dentoalveolar protrusion. But bimaxillary surgery cannot address all of complex deformity of mandible. The new technique using horizontal chin bar can treat mandibular dentoalveolar protrusion and chin retrusion in one setting. Objectives: To evaluate the results of mandible segmental osteotomy and jumping genioplasty;To illustrate the versatility and the ease of this procedure and to confirm the good to excellent clinical results obtained with minimal complications. Design: Retrospective study setting, all of the patients of university hospital and private practice who seek medical attention for long face and retruded (and/or deviated) chin were included in the study. Patients and surgeons satisfaction were evaluated. Results: 45 patients, aged 19 - 30 years (mean age, 24 ± 6 years) underwent the creation of a horizontal chin bar (4 - 7 mm wide) as an axis for two opposite bone movement (and a place for fixation) of mandibular dentoalveolar segment and lower chin segment [segmental lower jaw (Kolle’s) operation and genioplasty], and/or with concomitant Bimax. operation. The mean chin advancement was 8 mm (4 - 10 mm). Average setback for mandible was 3 mm (2 - 6 mm). No bone resorption was identified. No permanent nerve paresthesia was noted. There was one case of the bar fracture due to narrowness of the bar. 37 patients were highly satisfied and 8 were satisfied with the results. There was no dissatisfaction in our patients and surgeons. Conclusion: For long face and retruded chin one of the best treatments is horizotal chin bar method with very good long-term results. EBM: Level IV.

Face transplantation for massive mandibular defects: considerations for allograft design and surgical planning

Modern face transplant techniques have advanced to allow for the transfer of vascularized skeletal components in addition to overlying soft tissue.This represents significant opportunity for individuals with mandibular defects that are not amenable to traditional reconstruction.Care must be taken when planning and executing transplants with these complex grafts,as satisfactory functional and aesthetic outcomes rely on achieving proper spatial relationships between the mandible,skull base,and midface.Which donor skeletal elements are included in the allograft and how they are harvested are important considerations in this planning and are associated with controversy.To optimize outcomes in the reconstruction of single-jaw defects,some advocate for transplantation of only the affected jaw while others support bimaxillary transplantation.Clinical evidence in this debate is not conclusive at this time.In current practice,including donor dentoalveolar anatomy by utilizing a bilateral sagittal split osteotomy of the mandible is favored to optimize outcomes such as dental occlusion.It has been suggested that harvesting the mandible at the level of the condyle or even the temporal bone may also be possible and may improve temporomandibular joint-related outcomes.Despite encouraging preclinical evidence,these strategies remain controversial.After allograft design,successful mandibular reconstruction with face transplantation relies on surgical precision in the donor and recipient procedures.Computerized surgical planning,computer-aided design and manufacturing,and intraoperative navigation are technologies currently in use to mitigate operative complexity.Results in both cadaveric and clinical face transplantations suggest these technologies are reliable and beneficial,although some room for improvement remains.