Demineralized dentin matrix scaffolds for alveolar bone engineering.

From the point of view of implant dentistry, this review discusses the development and clinical use of demineralized dentin matrix (DDM) scaffolds, produced from the patient's own extracted teeth, to repair alveolar bone defects. The structure and the organic and inorganic components of DDM are presented to emphasize the similarities with autogenous bone. Studies of DDM properties, such as osteoinductive and osteoconductive functions as well as efficacy and safety, which are mandatory for its use as a bone graft substitute, are also presented. The clinical applications of powder, block, and moldable DDM are discussed, along with future developments that can support growth factor and stem cell delivery.

Risk of maxillary artery injury during an intraoral vertical ramus osteotomy in Japanese patients is high--is it enough just to avoid damaging the inferior alveolar nerve?

PURPOSE: Since managing a case in which the maxillary artery was injured during intraoral vertical ramus osteotomy (IVRO) with intraoperative transcatheter arterial embolization, we have conducted preoperative vascular computed tomography (CT) evaluations of the maxillary artery course in patients scheduled to undergo mandibular bone osteotomy. The aim of the present study was to describe the anatomy of the maxillary artery in the infratemporal artery in Japanese patients. MATERIALS AND METHODS: The study design was a prospective case series. The study sample included all patients who had undergone IVRO from October 2009 to December 2012. We evaluated the positional relationship between the maxillary artery and the mandible using CT vascular imaging before surgery. The primary outcome variable was the requirement for subperiosteal dissection on the medial surface of the mandible from the perspective of the intersection of the route of the maxillary artery with the IVRO osteotomy line. RESULTS: A total of 156 sides from 78 patients who had undergone mandibular bone osteotomy were included in the present study. The maxillary artery course was positioned directly below the mandibular notch in approximately one half of the cases, necessitating subperiosteal dissection on the medial surface of the mandible. CONCLUSIONS: IVRO is a common surgical procedure that can be safely and easily conducted in conjunction with endoscopy. However, improved maxillary artery damage prevention methods are recommended, such as subperiosteal dissection on the medial surface of the mandible and filling the medial surface of the mandibular ramus with gauze.

Endoscopically assisted intraoral modified Le Fort II type midfacial advancement using piezoelectric surgery and an intraoperative RED system.

PURPOSE: The Le Fort II midfacial advancement appears to be an effective surgical method for the treatment of severe midfacial-nose hypoplasia with a skeletal class III malocclusion, which is usually combined with syndromic midfacial anomalies. However, the conventional surgical method requires the coronal approach, including a coronal incision, together with other surgical approaches, such as an intraoral incision. Therefore, surgeons often hesitate to propose this type of osteotomy, even for patients who develop severe nonsyndromic midfacial-nose hypoplasia. This report presents a new surgical approach for performing a safe Le Fort II osteotomy for nasomaxillary, midfacial corrective advancement via a solely intraoral approach. MATERIALS AND METHODS: Surgery was performed with endoscopically assisted piezoelectric surgery. The osteotomized nasomaxillary Le Fort II segment was successfully protracted without aggressive down-fracture procedures with the sole intraoperative use of a rigid external distraction (RED) system, followed by internal rigid fixation, and the subsequent removal of the RED system. Seven patients (all patients were nonsyndromic, but 2 had cleft lip and palate, and an average age of 19.9 years) were included in this study. RESULTS: The degrees of midfacial advancement at the base of nasal bone (the top edge of the modified Le Fort II segment) that was osteotomized and at maxillary point A was 8.3 mm (range 5.8 mm to 10.5mm) and 8.5 mm (range 5.9 mm to 9.8 mm), respectively. CONCLUSION: This new method less invasively facilitates safe, secure, and ideal nasomaxillary midfacial protraction to yield a satisfactory resultant facial profile and favorable occlusion in patients with severe midfacial-nose hypoplasia and skeletal class III malocclusions.

Clinical approach for mandibular advancement by intraoral vertical ramus osteotomy with endoscopically assisted intraoral fixation of an L-shaped compact lock plate.

Intraoral vertical ramus osteotomy (IVRO) is widely used as a surgical corrective method to treat patients with skeletal class III malocclusion with mandibular setback. However, the conventional surgical method applied for mandibular advancement has induced such complications as condylar luxation caused by the instability of the placement of the proximal segment. To avoid this complication, it has been necessary to use the fixation of the proximal and distal segments with an L-shaped compact lock plate via an extraoral approach. This has made surgeons hesitate to propose this osteotomy for patients with skeletal class II malocclusions. We herein report a new surgical approach for the IVRO for mandibular corrective advancement with endoscopically assisted fixation of an L-shaped compact lock plate and good positioning of the condyle via an intraoral approach.The osteotomized mandibular segments were fixed with an L-shaped compact lock plate using right-angled burs and right-angled screwdrivers. Seven patients were included in this study. The average degree of mandibular advancement was 6.1 mm (range, 3.5-9 mm). Our results suggest that mandibular advancement by IVRO with endoscopically assisted intraoral fixation of an L-shaped compact lock plate in patients with skeletal class II malocclusion might be useful to improve the occlusion and facial aesthetics by maintaining good positioning of the condyle.

Bone transport and bone graft using auto-tooth bone for alveolar cleft repair.

We herein report the application of a combination of maxillary bone transport and auto-tooth bone grafting for alveolar cleft repair using autogenous extracted teeth developed in Korea.A 9-year-old female patient suffering from unilateral cleft lip and palate was treated with this method. After sagittal interdental right-sided maxillary osteotomy was performed completely between #11 and #12 to the nasal floor, alveolar maxillary bone (#11, 21) was transported in the planned direction and the alveolar cleft was closed. At the end of the transporter activation period, soft tissue in the cleft was removed during so-called "docking surgery" using an electric knife for close bone contact at the docking site. We performed bone transporter removal and simultaneous auto-tooth bone grafting of the patient's supernumerary teeth to the docking site.Maxillary bone transport allowed for simultaneous correction of the nasal septal deviation, maxillary arch deformities, and malocclusion since the dental arch was expanded without donor sacrifice or soft tissue expansion. Auto-tooth bone grafting to the docking site allowed for repair of the bone defects of the nasal floor and alveolar cleft and resulted in a superior bone connection.A combination of maxillary bone transport and auto-tooth bone grafting to the docking site appears to be an effective approach for alveolar cleft repair.

Submandibular approach through the submandibular gland fascia for treating mandibular fractures without identifying the facial nerve.

BACKGROUND: : The submandibular, or Risdon, approach is the classic, reliable extraoral approach for treating mandibular fractures. Although the intraoral approach has been used recently for open reduction and internal fixation, in some cases, such as comminuted fractures or fractures in an atrophic mandible, the submandibular approach is still prerequisite. Damage to the marginal mandibular branch of the facial nerve is the only concern other than skin scarring. METHODS: : To minimize the risk of neuropraxia, we prospectively assessed an approach for treating mandibular fractures at 24 surgical sites in 22 patients (17 men, 5 women; mean age, 54.3 years) using direct submandibular gland capsule fascial layer elevation that did not require identifying the facial nerve. RESULTS: : As complications, one patient (4.2%) had temporary facial weakness in the mandibular branch, but this resolved completely within 3 months. The postoperative clinical course was uneventful in the other patients with one minor fistula and minimal scarring. CONCLUSIONS: : In conclusion, submandibular gland capsular layer elevation without facial nerve identification is a safe and less time-consuming technique applying the submandibular approach for the treatment of mandibular fractures.

Oral rehabilitation of a maxillectomy defect using bone transport distraction and dental implants.

Bone transport distraction is a reliable procedure in various maxillofacial bony defect reconstruction techniques. It is minimally invasive and it eliminates donor site morbidity. We introduce a new surgical technique for maxillary backward bone transport distraction reconstruction performed in a 77-year-old woman with a posterior partial maxillary defect. Transport distraction was successful for posterior maxillary alveolar bony regeneration, which helped close an oroantral fistula. One month after the distraction device was removed, 3 dental implants were placed in the reconstructed alveolus, followed by successful oral functional rehabilitation by use of an implant-anchored prosthesis. Two and a half years have passed since the patient's dental implant-based prosthesis was activated, and the functional occlusal reconstruction by use of bone transport distraction and dental implants after repair of the maxillectomy defect has proven to be effective with patient satisfaction.

Speedy surgical orthodontic treatment with skeletal anchorage in adults--sagittal correction and open bite correction.

PURPOSE: The present report describes a new type of corticotomy-assisted orthodontic treatment called Speedy orthodontics, which allows faster movements of the dental segments using skeletal anchorage. MATERIALS AND METHODS: To minimize the risk of necrosis, 2 procedures are performed. During the initial surgery, bilateral and horizontal corticotomies are performed in the palatal area with the patient under local anesthesia. After 2 to 3 weeks, a second buccal corticotomy is performed and 500 to 900 g of force per side is immediately applied to the corticotomized segment. RESULTS: Successful alveolar bone bending can be obtained in cases of adult protrusion or open bite. CONCLUSIONS: Speedy orthodontics allows for more precise control of anterior segment retraction in adult protrusion patients and can be used for posterior segment intrusion. This technology is powerful, easy to apply, and provides a significant advance in surgical orthodontics.

Computer-simulated bi-directional alveolar distraction osteogenesis.

OBJECTIVES: Computer-based surgical planning allows surgeons to evaluate bone morphology in three dimensions and to perform accurate virtual surgery preoperatively. This study was performed to evaluate the feasibility of using preoperative surgical simulation to enhance the clinical outcome in patients undergoing bi-directional alveolar distraction osteogenesis. MATERIAL AND METHODS: Nine patients (mean age, 49 years; range, 20-61 years) with maxillary segmental alveolar defects following post-traumatic atrophy or disuse atrophy after periodontal tooth loss were enrolled in the study. All patients were scheduled for implant placement. Three-dimensional (3-D) morphological evaluation and virtual bi-directional distraction were performed with SimPlant CMF/OMS surgical simulation software (Materialise). In addition, use of an extraosseous bi-directional distraction device (V2-Alveolar Distraction System; Medartis AG) was evaluated during the 3-D alveolar regeneration simulation and resulting augmentation. RESULTS: Alveolar height regeneration and labial-buccal augmentation were planned preoperatively using surgical simulation software. New bone formation with sufficient vertical augmentation of 5.8 mm was observed. As we encountered strong palatal inclination, the angulation required for labial-buccal augmentation during active distraction was the maximum angulation of 40 degrees , even greater than that required in the preoperative simulation of 23.9 degrees . Furthermore, the labial-buccal augmented angulation was gradually decreased to 11.2 degrees at the time of implant placement. In all cases, implantation was successful at the well-augmented sites, with sufficient primary stability after a 3-month consolidation period. CONCLUSIONS: Preoperative 3-D simulation is a potentially valuable tool for treatment of the morphologically complicated oral-maxillofacial region. More realistic surgical simulations are anticipated with ongoing effort to collect and integrate clinical data into next-generation software.

Long-term skeletal stability after maxillary advancement with distraction osteogenesis in nongrowing patients.

PURPOSE: We assessed the long-term skeletal stability of the repositioned maxilla, midface in patients who underwent maxillary advancement using distraction osteogenesis (DO). PATIENTS AND METHODS: The study included 19 nongrowing patients with maxillary hypoplasia with a Class III relationship, a normally developed mandible, and follow-up after DO exceeding 2 years. Eleven men and 8 women participated, with a mean age at treatment of 20.7 years (range 15.4-33.4 years). Twelve patients had midfacial hypoplasia associated with a cleft lip and palate (CLP), and 7 patients had developed noncleft-related hypoplasia. The surgical treatment included our modified Le Fort I osteotomy in combination with intraoral (5 cases) or extraoral (14 cases) distraction devices. Distraction was started after a latency period of 5 to 7 days and continued until the proper convexity was obtained. After active distraction, a 3- to 4-week period of retention was allowed, followed by rigid internal fixation (IF) with or without distractor removal. Lateral cephalometric films before midfacial distraction (T0), after IF with or without distractor removal (T1), 6 months after T1 (T2), and 2 or more years (mean 2.8 years) after T1 (T3) were analyzed. The maxillary A-point in the Frankfort horizontal reference plane was used to assess the skeletal changes in the maxillary position (x, y) at each time point (T1-T3). In addition, we analyzed the differences in the devices and techniques. RESULTS: Midfacial DO was successful in all cases, resulting in a mean change obtained at point A of 10.3 mm (8.4 mm horizontally, 4.7 mm inferiorly). Point A underwent a moderate amount of skeletal relapse at T2 [0.4 mm (5%) horizontally and 0.6 mm (13%) superiorly], with a mean of 8% (0.6 mm) horizontally and 19% (1.0 mm) superiorly over the mean 2.8-year (2.0-4.8 years) follow-up. After long-term follow-up, the maxillary advancement with DO was stable in both CLP and non-CLP patients with maxillary hypoplasia. In addition, our original technique using a rigid external device provided the most reliable results in terms of skeletal stability. CONCLUSION: This retrospective study showed that DO of the maxilla gives a very stable midface, offering a promising treatment alternative for patients with maxillary hypoplasia.

Variation of plate fixation for mandibular advancement with intraoral vertical ramus osteotomy using endoscopically assisted intraoral rigid or semi-rigid internal fixation: Case series study: Postoperative condylar seating control for mandibular advancement.

The purpose of the present study was to evaluate the safety and efficacy associated with mandibular advancement by intraoral vertical ramus osteotomy (IVRO) with endoscopically assisted intraoral rigid or semi-rigid internal fixation. The study sample included all patients who had undergone an mandibular advancement by IVRO procedure with endoscopically assisted intraoral plate fixation from September 2008 to May 2012. An mandibular advancement by IVRO with endoscopically assisted intraoral rigid or semi-rigid internal fixation was used for mandibular advancement. The patients were analyzed prospectively, with more than 2 years of follow-up, and were evaluated in terms of functional results, postoperative complications, and skeletal stability. A total of 14 patients (bilateral, 7 patients with class II; unilateral, 7 patients with asymmetry) were included in the present study. The average degree of mandibular advancement was 5.5 ± 1.9 mm (range, 3-9 mm). Both the occlusal relationship and facial appearance in all patients were significantly improved by the surgical-orthodontic treatment, with no major harmful clinical symptoms. In addition, one-screw semi-rigid fixation could control postoperative passive condylar seating. This study showed that mandibular advancement by IVRO with endoscopically assisted, intraoral semi-rigid internal fixation offers a promising treatment alternative for patients with skeletal class II malocclusion or facial asymmetry.

Combination of Mandibular Constriction and Intraoral Vertical Ramus Osteotomies for a Transverse Jaw Discrepancy.

BACKGROUND: The aim of the present study was to evaluate the treatment of patients developing a transverse jaw width discrepancy who exhibited class III malocclusion and/or facial asymmetry by a combination of mandibular constriction (MC) and intraoral vertical ramus osteotomies (IVROs). SUBJECTS AND METHODS: In a retrospective study, functional results, postoperative complications, and skeletal stability were analyzed for all the patients who had undergone MC and IVRO, with more than 2 years of follow-up. A mandibular midline osteotomy for constriction with lag screw technique and IVROs was used for MC and setback. RESULTS: Sixteen patients were included in the present study. The average degree of MC was 6.34 mm. Both the occlusal relationship and facial appearance in all patients were significantly improved by the surgical orthodontic treatment, with no harmful clinical symptoms. In addition, our original MC using lag screw technique provided the most reliable results in terms of skeletal stability. CONCLUSIONS: This study showed that MC using lag screw technique gives a very stable mandibular width constriction, and the combination of MC and IVROs offers a promising treatment alternative for patients with mandibular prognathism developing a transverse jaw width discrepancy.

Autogenous tooth bone graft block for sinus augmentation with simultaneous implant installation: a technical note.

In cases of severe alveolar bone atrophy in the posterior maxillary area, which has only a thin sinus floor, the autogenous tooth bone graft block (ABTB) was used to wrap the implant to enhance its primary stability and osseointegration in the sinus. These cases with four years of clinical follow-up demonstrate the applicability of the ABTB in maxillary sinus membrane elevation to improve the outcomes of implant placement.

Rotational Distraction for the Treatment of Severe Mandibular Retrognathia.

BACKGROUNDS: The main problem with intraoral distraction of the mandible is the inability to achieve the three-dimensional mandibular correction as planned preoperatively. We developed a technique that allows spontaneous changes in the direction of mandibular elongation using an intraoral distractor. METHODS: After mandibular osteotomy, the distractor is fixed to the distal segment of the mandible using a single bicortical screw, allowing anterior-posterior, vertical and limited lateromedial changes in the vector of distraction. Mandibular lengthening is performed while keeping the maxilla and mandible in class I occlusion with intermaxillary fixation. RESULTS: As the distraction device is activated allowing mandibular elongation, the proximal segment, guided by the surrounding soft tissues, moves and rotates posterosuperiorly. Mandibular lengthening is continued until the condylar head reaches an adequate position in the mandibular fossa as confirmed clinically and radiographically. CONCLUSION: Thirty-three patients with mandibular retrognathia received this treatment and good results were obtained.

Three-dimensional virtual operations can facilitate complicated surgical planning for the treatment of patients with jaw deformities associated with facial asymmetry: a case report.

This article describes a case we experienced in which good postsurgical facial profiles were obtained for a patient with jaw deformities associated with facial asymmetry, by implementing surgical planning with SimPlant OMS. Using this method, we conducted LF1 osteotomy, intraoral vertical ramus osteotomy (IVRO), sagittal split ramus osteotomy (SSRO), mandibular constriction and mandibular border genioplasty. Not only did we obtain a class I occlusal relationship, but the complicated surgery also improved the asymmetry of the frontal view, as well as of the profile view, of the patient. The virtual operation using three-dimensional computed tomography (3D-CT) could be especially useful for the treatment of patients with jaw deformities associated with facial asymmetry.

Tooth-derived bone graft material.

With successful extraction of growth factors and bone morphogenic proteins (BMPs) from mammalian teeth, many researchers have supported development of a bone substitute using tooth-derived substances. Some studies have also expanded the potential use of teeth as a carrier for growth factors and stem cells. A broad overview of the published findings with regard to tooth-derived regenerative tissue engineering technique is outlined. Considering more than 100 published papers, our team has developed the protocols and techniques for processing of bone graft material using extracted teeth. Based on current studies and studies that will be needed in the future, we can anticipate development of scaffolds, homogenous and xenogenous tooth bone grafts, and dental restorative materials using extracted teeth.

Simultaneous sinus lifting and alveolar distraction of a severely atrophic posterior maxilla for oral rehabilitation with dental implants.

We retrospectively reviewed a new preimplantation regenerative augmentation technique for a severely atrophic posterior maxilla using sinus lifting with simultaneous alveolar distraction, together with long-term oral rehabilitation with implants. We also analyzed the regenerated bone histomorphologically. This study included 25 maxillary sinus sites in 17 patients. The technique consisted of alveolar osteotomy combined with simultaneous sinus lifting. After sufficient sinus lifting, a track-type vertical alveolar distractor was placed. Following a latent period, patient self-distraction was started. After the required augmentation was achieved, the distractor was left in place to allow consolidation. The distractor was then removed, and osseointegrated implants (average of 3.2 implants per sinus site, 80 implants) were placed. Bone for histomorphometric analysis was sampled from six patients and compared with samples collected after sinus lifting alone as controls (n = 4). A sufficient alveolus was regenerated, and all patients achieved stable oral rehabilitation. The implant survival rate was 96.3% (77/80) after an average postloading followup of 47.5 months. Good bone regeneration was observed in a morphological study, with no significant difference in the rate of bone formation compared with control samples. This new regenerative technique could be a useful option for a severely atrophic maxilla requiring implant rehabilitation.

Simultaneous sinus lifting and alveolar distraction of the atrophic maxillary alveolus for implant placement: a preliminary report.

This article describes a procedure for performing simultaneous sinus lifting and alveolar distraction to augment an atrophic maxillary alveolus. This technique is a 1-stage operation that is indicated when the amount of native sinus floor bone is minimal (<5 mm). The technique is contraindicated when there is <2 mm of sinus floor,when a 2-stage operation is needed (sinus lifting, alveolar distraction osteogenesis). Postoperative complications are minimal.

Maxillary bone transportation in alveolar cleft-transport distraction osteogenesis for treatment of alveolar cleft repair.

Secondary autogenous cancellous bone grafting is a widely used method for the treatment of alveolar clefts and oronasal fistulae. However, failure of iliac bone grafting sometimes occurs due to inadequate covering with the surrounding soft tissue and marked scar formation, inappropriate patient age, or large clefts. For alveolar clefts, we developed a method consisting of alveolar bone transportation, closure of the alveolar cleft, and/or grafting of new bone. Transport distraction osteogenesis along the curve of the dental arch is ideal. Alveolar bone was transported in the planned direction using a ready-made bone-borne distractor in combination with an orthodontic arch wire for transport guidance. This method allows simultaneous correction of nasal septal deviation and also correction of maxillary arch deformities and malocclusion since, the dental arch is expanded without donor sacrifice. This method can be regarded as tissue engineering to expand bone tissue. This method can be safely performed not only in patients undergoing initial treatment for alveolar clefts but also in patients in whom bone grafting has failed. Since 1997, we have performed this method in 22 patients and obtained good results.