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At least 415 records · Page 23Linked to original sources
PubMed1994

New bone formation by biological rhythmic distraction.

Bone regeneration by distraction has become an accepted method for correction of congenital and acquired deformities. Unifocal bone generation is discussed as a technical note to demonstrate its feasibility in craniofacial surgery. The technique is simplified by the reorientation of the apparatus used, and the distraction is performed over a period of time to achieve a balance in the facial skeleton. Orthodontic elastics are used to balance the occlusion.

Bone Lengthening↗
PubMed1995

Geometric evaluation of mandibular distraction.

In planning mandibular distraction, the deficiency of the vertical ramus and body is measured. The position of the pin placement is evaluated by the following formula: [formula: see text] This is more accurately presented by the new formula. [formula: see text] In one patient the original formula evaluated the pin placement angle to be 9.94, compared with 9.92, in the more accurate but more complex new formula. When the gonial angle is obtuse, the difference is small. When the gonial angle is more acute, as in a normal gonial angle for a 2-year-old child--134 degrees--the difference is still only 0.1 degree. The original formula is simpler to use and is accurate enough for clinical use in mandibular distraction. The distraction distance is not the sum of the vertical ramal deficiency plus the body deficiency but is given by the following formula: [formula: see text] It would be accurate enough to plan the total distraction distance to be less than the sum of the two distances. The more acute the gonial angle is, the less the distraction distance will need to be.

Adolescent↗
PubMed1996

Correction of mandibular hypoplasia by means of bidirectional callus distraction.

The method of gradual callus distraction proved to be very useful in augmenting hypoplastic mandibles. When performing our first series using a unidirectional distractor, we faced some problems in determining the direction of lengthening. Moreover, postoperative adjustments were not possible. On the basis of this experience, we developed a bidirectional lengthening device consisting of two limbs and a variable angulation piece. This allows distinct control of the vertical and horizontal components of the distraction. The method proved effective and reliable in 18 patients with various degrees of mandibular hypoplasia. The median follow-up period was 10 months (range, 1-19 months).

Adolescent↗
PubMed2000

Treatment of micrognathia with edentulous maxilla by sagittal split mandibular osteotomy and a subperiosteal implant immobilized with transmaxillary screws.

Micrognathia complicated by edentulous maxilla was treated by performing sagittal-split mandibular osteotomy and immobilizing a subperiosteal implant using transmaxillary screws. The patient was a 42-year-old man who had a birdlike facial deformity caused by significant hypoplasia of the mandible. He also demonstrated significant malocclusion attributable to micrognathia and edentulous maxilla caused by resorption of the alveolar bone. These conditions impaired his mastication and articulation, making it impossible for him to eat regular food or carry out normal conversation. A subperiosteal implant was placed on the edentulous maxilla, and was rigidly immobilized to the maxilla using five transmaxillary screws. A prosthesis was then attached to the implant, and by using the implant as the point of reference and the anchor, the mandible was moved forward by sagittal-split mandibular osteotomy. Intermaxillary fixation was subsequently performed. The postoperative course has been favorable, and his facial complexion has improved significantly. One and a half years after his surgery, there has been no sign of complications or malocclusion caused by mandibular retraction. He is now able to eat regular food and speak normally.

Adult↗
PubMed2000

Complete congenital bony syngnathia in a case of oromandibular limb hypogenesis syndrome.

Congenital fusion of the maxilla and mandible (syngnathia) is rare and can present in a wide range of severity from single mucosal bands (synechiae) to complete bony fusion (synostosis). Congenital synostosis of the mandible and maxilla is even less common than synechiae, with only 19 cases reported in the literature. Most of them have presented as an incomplete, unilateral fusion. Only three of the reported cases showed more extensive but still incomplete, intermaxillary bony fusion. We present a case of complete bony fusion of the maxilla and mandible associated with a cleft palate, hypoglossia, micrognathia, unilateral choanal atresia, and limb abnormalities as a feature of oromandibular limb hypogenesis syndrome. Details of operative management are presented.

Choanal Atresia↗
PubMed2001

Imaging the neonatal mandible for accurate distraction osteogenesis.

The position of mandibular teeth is difficult to document in the neonatal patient. Panorex images are difficult to obtain in an uncooperative pediatric patient. The new technique presented by the authors uses computed tomographic data to create a curved, reformatted image of the mandible, and generates an image similar to a panorex image. This curved, reformatted mandibular image provides accurate visualization of the mandible and mandibular teeth. This technique allows for precise pin placement and osteotomy in distraction osteogenesis.

Humans↗
PubMed2001

Cleft palate in a patient with Williams' syndrome.

Cleft lip or palate has not been reported in the medical literature as a part of Williams' syndrome. We present a patient who had cleft palate among other congenital manifestations. This patient's immediate postnatal period clinically seemed to have a Pierre Robin sequence. With the development of the craniofacial complex, microgenia and micrognathia with glossoptosis gradually became apparent. On further assessment, the patient showed other clinical findings that suggested a syndromic association. This required a complete evaluation to discard other conditions that present with low psychomotor development and distinctive facies, such as Kabuki syndrome or fetal alcohol syndrome. The diagnosis for Williams' syndrome was established based on the clinical features and supported by the fluorescent in situ hybridization test. Williams' syndrome has been described as a rare, congenital disorder characterized by physical and developmental problems. Common features include characteristic "elfin-like" facies, supravalvular aortic stenosis, hypercalcemia, low birth weight, slow weight gain, feeding problems, impulsive and outgoing personality, limited spatial skills and motor control, and intellectual disability. Although individuals with Williams' syndrome may show competence in areas such as language, music, and interpersonal relations, their IQs are usually low and they are considered moderately to mildly retarded.

Child, Preschool↗
PubMed2001

Early treatment of severe mandibular hypoplasia with distraction mesenchymogenesis and bilateral free fibula flaps.

The technique of distraction has revolutionized the treatment of mandibular hypoplasia; however, presently large mandibular defects still require bone grafts. Microvascular grafting is commonly used in adults. Conversely, in pediatric reconstruction, nonvascularized rib grafts remain standard. Unfortunately, resorption of nonvascularized bone remains a major issue, particularly when soft tissue is hypoplastic. This case study represents a combination of techniques in the treatment of severe mandibular deficiency, and introduces the concept of distraction mesenchymogenesis. The patient was a 2 1/2-year-old boy with severe bilateral Pruzansky class III mandibular hypoplasia. He had a permanent open mouth posture, an overjet of 23 mm, and was unable to move the lower mandibular segment. His oropharyngeal airway diameter was 2.2 mm and he was tracheostomy dependent. The patient was treated with distraction of the lower jaw mesenchyme followed by bilateral functional free fibular microvascular flaps containing reinnervated muscle. This created a well-vascularized body, ramus, and condyle bilaterally within an adequate soft-tissue envelope. Postoperatively, the overjet was reduced to 5 mm. The patient can now actively move his mandible. Airway diameter increased to 10 mm, and the patient is able to tolerate intermittent tracheostomy plugging. This innovative combination of techniques allows early intervention, limits graft resorption, and improves airway control.

Airway Obstruction↗
PubMed2002

Mandibula distraction osteogenesis for lengthening the mandibula to correct a malocclusion: a more than 70-year-old German concept in craniofacial surgery.

Bone distraction is still on the rise again since McCarthy et al. presented in their clinical investigation new osseous formation in the elongated area while performing the distraction of the mandible in 1992. But at the level of craniofacial skeleton, the initial description to the technique of distraction osteogenesis should be credited to the German craniofacial surgeons Rosenthal for the bone lengthening of the mandible in a microgen patient in 1927. The procedure is described and the original schedules and case are presented.

Germany↗
PubMed2002

Le Fort III distraction osteogenesis of midface-retrusion in a case of Hajdu Cheny syndrome.

Le Fort III maxillary distraction osteogenesis using the RED system and advancement genioplasty was successfully performed for the midfacial retrusion and to eliminate severe snoring during sleep in a rare case of Hajdu Cheny syndrome. This syndrome is characterized by slowly progressive systemic osseous dysplasia, exhibiting craniofacial disfigurements and other skeletal deformity, but no description is found in a plastic surgical treatment up to now. A rare entity of this syndrome is also presented.

Adolescent↗
PubMed2003

Correction of upper airway obstruction in the newborn with internal mandibular distraction osteogenesis.

Tracheostomy for management of neonatal airway obstruction may be life saving but is associated with complications and developmental problems. As an alternative, the effectiveness of internal mandibular distraction osteogenesis was investigated in select neonatal patients with micrognathia and upper airway obstruction. Preoperative tests (sleep study, direct laryngobronchoscopy, and "milk scan" for GI reflux) were used to select appropriate candidates for the procedure. Excluded were patients with 1) central apnea, 2) severe reflux, 3) other airway lesions, and 4) mild to moderate obstruction controlled by positioning. Of 44 newborns (aged <3 weeks) with upper airway obstruction and micrognathia seen in the neonatal intensive care unit, 19 underwent tracheostomy, 10 were discharged with home monitoring and positional instructions, and 15 underwent bilateral mandibular lengthening with microdistractors. Of those who underwent mandibular distraction, a tracheostomy was avoided in 14 of 15 patients. Relative improvement in the posterior airway space was seen on 3D CT scans, cephalograms, and laryngobronchoscopies obtained preoperatively, postoperatively, and during follow-up evaluation. One of these 15 patients required a tracheostomy for postoperative central apnea. In an average of just 4.5 days following completion of distraction, patients were discharged home with improved oral feeding and no feeding tube. This study suggests that for selected newborns, the use of internal microdistractors allows for avoidance of a tracheostomy and improved oral feeding.

Airway Obstruction↗
PubMed2003

Distraction osteogenesis of the mandible with an internal bioresorbable device.

Lengthening of the mandible by distraction osteogenesis has been shown to be an effective treatment of hypoplastic mandibles. Use of an internal technique with a bioresorbable distraction device is presented. Mandibular lengthening was performed in seven patients aged 3.2 to 7 years. Six of the patients were diagnosed with craniofacial microsomia, anthe buccal aspect of the mandible, and distraction was started on the second postoperative day at the rate of d one was diagnosed with Nager syndrome. An internal bioresorbable device was placed along 1 mm/d and continued for 17 to 20 days. The distractor screw was maintained for retention for an additional 6 weeks and was then removed. All the patients showed clinical improvement. The postdistraction craniofacial computed tomography scans demonstrated elongation of the mandible with increase in the bony mass. The complications included device failure in one patient. The advantage of this method compared with the internal metal device is that it does not necessitate an additional procedure for device removal.

Absorbable Implants↗
PubMed2004

New internal Le Fort I distractor for the treatment of midface hypoplasia.

A new Le Fort I internal distraction device was developed by one of the authors (J. G.) and successfully used on a patient with cleft lip and palate and severe maxillary hypoplasia. The device consisted of an upper plate and a lower plate, which were installed above and below the Le Fort I osteotomy. The upper plate was shaped like a "U," and the lower plate was shaped like an inverted "U." The design of the device was unique in that the distraction screws were placed in the maxillary sinus and orientated parallel to the sagittal plane. Presurgical planning used a stereolithographic (STL) model and the CASSOS software to calculate the distraction vector. The distractors were prebent and installed on the STL model and activated to advance the maxilla 15.5 mm. Surgery was performed in a conventional manner, and distraction was started on the seventh day after surgery. At the completion of distraction, a total of 15.5 mm of distraction was achieved. The distractors were removed 3 months after surgery. Results showed that the patient's severe maxillary hypoplasia was corrected as predicted and there was excellent new bone formation between the edges of the osteotomy.

Adolescent↗
PubMed2004

Neonatal distraction surgery for micrognathia reduces obstructive apnea and the need for tracheotomy.

The objective of the study was to assess the effectiveness of neonatal mandibular distraction in treatment of obstructive sleep apnea in the perinatal period in preventing a tracheotomy. This was a prospective study of 17 infants at two centers with severe micrognathia who demonstrated obstructive sleep apnea refractory to conservative therapy. Age at surgery varied from 5 to 120 days. Distraction was performed at a rate of 2 mm/d. After distraction, callus consolidation was allowed for 4 to 6 weeks, and the device was then removed. Each child underwent a three-dimensional computed tomography scan before surgery and approximately 3 months after surgery. Of the 17 patients, 14 successfully underwent extubation and demonstrated significant improvement in the obstructive sleep apnea. Postoperative horizontal ramus length increased from 23.3 to 34.8 mm after surgery. Mean maxillary mandibular discrepancy was 8.28 mm before surgery and 2.2 mm after surgery. Ten infants who underwent pre- and postoperative polygraphic studies showed improvement in obstructive apnea. Three patients had postoperative polysomnographic studies only; the results were also within the normal range. The mean follow-up interval was 16.5 months (range: 8-48 months). Neonatal distraction is an effective method for treatment of micrognathia with obstructive sleep apnea in the perinatal period in preventing a tracheotomy.

Airway Obstruction↗
PubMed2004

Mandibular distraction osteogenesis by sagittal split osteotomy and intraoral curvilinear distraction.

Mandibular distraction combining the sagittal split ramus osteotomy and an intraoral curved distractor is efficacious to lengthen the mandibular body and ramus. The sagittal split permits immediate rotation of the proximal segment and lengthening while still providing a large surface interface for regenerative bone. The buried curved distractor enables mandibular lengthening along the normal logarithmic grow spiral as shown by Moss and Rickets. In addition, it is well tolerated by the patient and can remain in place for a long duration to provide support. In summary, this combination of surgical techniques provides certain advantages for distraction of the mandible.

Adult↗
PubMed2004

Congenital trismus secondary to masseteric fibrous bands: a 7-year follow-up report as an approach to management.

A 7-year prospective follow-up report, which was previously presented in this journal as an initial pediatric case report, is presented as an approach to management of congenital trismus secondary to masseteric fibrous bands. Adams and Rees discussed management, including endoscopic exploration at 18 months of age with early recurrence of trismus. Under the care of the same plastic surgeon and his team, the progress of this patient over 7 years has given us an insight into management. The cause of trismus is not fully elucidated, but the condition can result in compromised caloric intake, speech development, facial appearance, dental care, and oral hygiene. The decreased oral opening may be secondary to shortening of the muscles of mastication, which may cause tension moulding and distortion of the coronoid process; yet, there is no consensus on the optimal management of temporomandibular joint trismus and all its causes. The patient presented in this report, now aged 7 years, has proceeded through to open surgery on two occasions yet, regrettably, has persistently tight masseter muscles and only 8 mm of jaw opening.

Endoscopy↗
PubMed2004

Treatment of temporomandibular joint ankylosis in children: is it necessary to perform mandibular distraction simultaneously?

Temporomandibular joint (TMJ) ankylosis in children disturbs not only mandibular growth, but also facial skeletal development. Costochondral graft was used to ensure growth, but it had proven to be unpredictable. The authors evaluate retrospectively 41 patients who underwent temporomandibular joint reconstruction during the last 10 years. Twenty were treated by costochondral graft, 15 by arthroplasty, and 6 by other surgical procedures, and they were excluded. The etiology was septic in 54% of the cases. Follow-up was at least 12 months in all cases. Arthroplasty was a quicker and easier procedure than the costochondral graft, reducing operating time, risk of blood transfusion, and hospital stays and costs. It also was associated with less risk of reankylosis, 13%vs 25%. Furthermore, it was associated with a minor morbidity and secondary complications. Seventy-five percent of the patients treated with bone graft required additional secondary surgery. Radiographically, the authors observed a remodeled neocondyle at the level of proximal mandibular end in cases treated by arthroplasty. On clinical examination, patients showed variable degrees of facial deformity and an unknown potential of mandibular growth after TMJ arthroplasty. The authors also observed improved clinical and radiologic appearance after ankylosis correction. Is it reasonable to perform ankylosis release and mandibular distraction simultaneously without knowing which patients will be able to experience growth with time? In that case it would be necessary a predict growth to apply the exact amount of mandibular distraction for obtaining stable results. Timing of mandibular distraction, after TMJ arthroplasty is performed and mandibular function restored, must be specific to each patient's needs, assuring the best distraction conditions and planning. The authors present their treatment protocol, including TMJ joint arthroplasty with temporal muscle interposition, and mandibular distraction osteogenesis, as a second procedure, to correct residual asymmetry or retrognathism if necessary.

Adolescent↗
PubMed2004

Swallowing disorders in Pierre Robin sequence: its correction by distraction.

Pierre Robin sequence is characterized by micro-gnathia, glossoptosis, feeding difficulties, and upper respiratory obstruction, which are frequently complicated by bronchial aspiration and pulmonary infection. Gastroesophageal reflux is also common in these patients. To assess the results of mandibular distraction, a study was performed in 18 patients to detect swallowing disorders associated with apnea episodes and gastroesophageal reflux. Polysomnography, barium pharyngoscopy, determination of blood gases, and esophageal pH measurements were undertaken before and 4 months after distraction osteogenesis. Bilateral corticotomies, followed by distraction with external devices, were performed, achieving 7 to 19 mm of elongation (mean = 12 mm). Gastroesophageal reflux was found in 83% of cases associated with apnea episodes, but it disappeared after distraction osteogenesis. Mean preoperative oxygen saturation was 72%, and it was 93% afterward. The preoperative apnea index was 18.3, and the preoperative 8.5 hypopnea index was 8.5; both disappeared. Pharyngeal transit time became less than 1 second after treatment. Abnormal tongue movements and barium stasis in the pharyngeal recess and in the trachea were eliminated in all the patients.

Deglutition Disorders↗