What the patients and parents do not tell you-recollections from families following external LeFort III midface distraction

OBJECTIVE

The purpose of this study was to document the experience of patients and parents of patients who had recently undergone LeFort III midface distraction using an external halo-based device.

DESIGN

Cross-sectional study.

SETTING

A craniofacial center in a pediatric tertiary care medical center.

SUBJECTS

Eight children who had undergone midface distraction within 1 year of the interview and their caregivers.

INTERVENTION

Semi-structured interview.

MAIN OUTCOME MEASURE

Transcripts of the interviews were rendered anonymous and analyzed by our multi-disciplinary team. Consistent themes in the subjects' experience during and after midface distraction were identified.

RESULTS

(1) Family participation in the decision to undergo distraction and pre-operative preparation was recognized as valuable, but parents identified that there are inherent limitations; (2) home-care tasks seemed daunting pre-operatively but were easier than expected; (3) discomfort, sleeping, and interaction with peers were considered well accommodated, but feeding was challenging; (4) individualized pre-operative plans for community support was important; (5) parents and patients were impressed by the change in appearance, specifically in the peri-orbital region; (6) access to team members and to parents of patients who had participated in the distraction process was invaluable.

CONCLUSION

External midface distraction is a valuable clinical technique, but requires intensive preparation and support from a multi-disciplinary team. We provide suggestions for consideration by centers initiating and refining patient care plans for this surgery.

Pin-tract infection during limb lengthening using external fixation

We evaluated the incidence of pin-tract infection (PTI) during limb lengthening using external fixation in 88 patients and the effects of infection on final outcomes and incidence of additional procedures. The PTI rate was 96.6%. The rate of half-pin site infection was significantly (P<.05) higher in half-pin fixators (100%) than in hybrid fixators (78%). There was a significantly (P<.05) higher incidence of half-pin site infection (78%) than fine-wire site infection (33%). The rate of additional surgeries for treating PTI was higher for half-pin sites than for fine-wire sites. Three (3.4%) of the 88 cases led to chronic osteomyelitis. Careful insertion and a simple, well-defined, excellent pin-care protocol can minimize PTI.

Distraction osteogenesis for ridge augmentation: prevention and treatment of complications. thirty case reports

Distraction osteogenesis (DO) is the latest addition to the variety of alveolar ridge augmentation procedures used to increase the volume of bone prior to implant placement. Thirty DO procedures were performed in 30 patients using 17 intraosseous and 13 extraosseous devices to augment deficient alveolar ridges. Fifty-five implants placed in the distracted bone were followed for a period of 34 to 60 months after loading. Five implants failed, for a 90.9% success rate. Vertical augmentation ranged from 3.5 to 13.0 mm (average, 7.8 mm). At least one complication was encountered, requiring additional hard or soft tissue surgery, in each of the 30 reported cases. This paper reviews complications encountered in the DO-treated patients, suggesting solutions and measures to prevent these problems.

Morbidity related to "endo-corticotomies" for transpalatal osteodistraction

INTRODUCTION

The objective of this study was to evaluate morbidity arising from transnasal, endoscopically assisted corticotomies for transpalatal osteodistraction. This minimally invasive technique utilizes three 1-cm incisions in the nasal vestibule instead of the classical, two lateral and one medial oral vestibule incisions of 2-3 cm and 1cm long, respectively.

MATERIAL AND METHODS

Fifty-nine patients (33 females and 26 males; age range: 9-50 years, mean 20 years) who underwent surgery in the hub hospital by the senior surgeon were included in a prospective registry. Patients with congenital maxillary hypoplasia were excluded. Difficulties were systematically recorded.

RESULTS

Mean operative time was 68 min (SD: 15 min) when no other procedures were combined with the transpalatal osteodistraction. Ten difficulties unrelated to either the device or oral hygiene were encountered: rhinorrhoea and minor nasal obstruction (1), nasal bleeding with hospital admission (1), periostitis at the piriform aperture that necessitated revision using local anaesthesia (1), periostitis with spontaneous healing (1), postoperative pain (2), dermatitis (1), infraorbital ecchymosis (1), excessive postoperative oedema (1), and prolonged cheek hyperaesthesia (1).

DISCUSSION AND CONCLUSION

Operative time as well as both percentage and nature of complications was similar to those experienced with "open-sky TPD" (transpalatal distraction), with less pronounced oedema and patient surgical threshold decreased.

Vertical distraction of the severely resorbed edentulous mandible: an assessment of treatment outcome

PURPOSE

To assess the treatment outcome (implant survival, surgical complications, patient satisfaction) of vertical distraction of the severely resorbed edentulous mandible.

MATERIALS AND METHODS

Forty-six patients with severe resorption of the edentulous mandible (bone height 5 to 8 mm, median 6 mm) participated in this study. The anterior segment of the mandible was vertically augmented using the Groningen distraction device. One or 2 months after the last day of distraction, 2 implants (n = 92) were placed. Standardized clinical and radiographic assessments were performed annually, and patient satisfaction was scored on a 10-point rating scale (0 = completely dissatisfied; 10 = completely satisfied).

RESULTS

Three implants were lost during the healing phase, but none were lost for the rest of the follow-up period (72 +/- 10.3 months), resulting in an implant survival rate of 97%. One patient developed a fracture of the mandible 3 days after the last day of distraction; it healed uneventfully. The mean mandibular bone resorption during follow-up as measured on radiographs in the midline and distal of the implants was 9.8% +/- 0.6% and 10.2% +/- 0.8%, respectively. In 4 patients radiolucency in the distracted area persisted during the follow-up period. Four patients reported a slight sensory disturbance at the final evaluation visit. All patients functioned well with their prostheses. The mean patient satisfaction score after treatment was 8.1 +/- 1.2.

CONCLUSION

Vertical distraction of the anterior segment of a severely resorbed alveolar ridge of the mandible can provide a proper basis for insertion and osseointegration of endosseous load-bearing implants with good implant survival, few surgical complications, and good patient satisfaction.

Minimizing pin complications when using the rigid external distraction (RED) system for midface distraction

In this review we describe the advantages, complications, and preventive considerations encountered as a result of the use of a halo for distraction of a retrusive nasomaxillary complex. Distraction osteogenesis is a well accepted combined orthodontic-surgical technique used in the treatment of patients with hypoplastic craniofacial components. The rigid external distraction (RED) system is a useful external distraction device for the advancement of severe retrusive maxilla especially in cleft palate patients. However, the addition of this new technique to the surgeon's armamentarium is accompanied by new complications and risks. Review of the literature on complications of the use of halo revealed that most complications are pin related. Complications with the use of RED have mainly included the penetration of intracranial pins. Risk management and preventive considerations propose several procedures to minimize the side effects when using RED: preoperative skull computerized tomography, pediatric neurosurgical consultation, proper pin care during distraction, frequent monitoring of the patient's general condition, proper pin and torque design, and special attention to the removal process of the RED.

Complications associated with distraction osteogenesis for the correction of brachymetatarsia: a review of five procedures

BACKGROUND

Congenital brachymetatarsia is often treated with callus distraction. This technique is associated with a variety of complications. We investigated complications encountered in treatment of brachymetatarsia in four female patients and reviewed adjunctive procedures performed to treat these complications.

METHODS

We reviewed five distraction osteogenesis procedures performed in four female patients with congenital shortening of the fourth metatarsal over a 3-year period. Serial radiographs were obtained weekly until bone consolidation was achieved, at which time the external fixator was removed. Follow-up ranged from 5 to 10 months.

RESULTS

Three patients (four metatarsals) were satisfied with the cosmetic and functional outcomes of their procedure. One patient was dissatisfied with the cosmetic result owing to a short digit from a short proximal phalanx but was completely functional and resumed all of her normal activities. Complications associated with callus distraction were decreased range of motion and stiffness at the metatarsophalangeal joint, flexion deformity of the digit, angulation of the metatarsal, prolonged distraction time due to pain, fracture of the bone callus, pin-site infection, and an undesirable cosmetic appearance due to a short proximal phalanx. Adjunctive procedures were needed in some of these cases and yielded good results.

CONCLUSIONS

Callus distraction is an effective treatment for congenital shortening of the fourth metatarsal, but the procedure is associated with a number of complications. Because most patients proceed with surgery for cosmetic reasons, it is important to present the possible complications and the adjunctive surgical procedures that may be necessary for a desirable outcome.

Complications and relapse in alveolar distraction osteogenesis in partially dentulous patients

Vertical distraction of the alveolar process is an efficient method for augmentation prior to inserting dental implants. In this study, complications of this procedure and relapse of the transport segment were evaluated in partially dentulous patients. Twenty patients underwent distraction by means of extraosseous distractors. The location of the defects was the anterior mandible (4), posterior mandible (4), anterior maxilla (10) and posterior maxilla (2). Bone height was measured on panoramic radiographs preoperatively, after distraction and after implant placement at the mesial and distal point of the implant(s). Mean alveolar distraction was 6.5mm at the mesial point (P<0.001) and 6.1mm at the distal point (P<0.001). The mean relapse at the mesial point was 20% and at the distal point 17% (P<0.05). The intraoperative and postoperative problems encountered were fracture (1) and lingual (4) and palatal (6) displacement of the transport segment. Overall complication rate was 55%. Of all implants placed (n=63) one was lost. Implant success rate was 98%. Distraction seems to be a suitable treatment for vertically deficient alveolar bone, but a relatively high although manageable complication rate must be confronted, including considerable relapse.

Gradual reduction of distal radial malunion using distraction osteogenesis

PURPOSE

To evaluate gradual distraction lengthening or distraction osteogenesis as a technique for treating malunions of the distal radius.

METHODS

Twenty patients with clinical and radiographic evidence of distal radius malunion were treated with osteotomy of the distal radius using distraction osteogenesis. At the follow-up evaluation each patient was evaluated for healing rates, complications, resolution of pain, and radiographic alignment. Surgical treatment consisted of an application of a nonbridging external fixator that could be distracted to correct the deformity. A loosely set screw that connected the distal pins to the fixator served as a hinge and allowed the distal radius to rotate into a corrected position. Gradual distraction via distraction osteogenesis was initiated 1 week after surgery.

RESULTS

Seventeen osteotomies healed uneventfully in an average of 9 weeks. Complications included 9 pin track infections. Two nonunions required bone grafting. One patient inadvertently compressed rather than distracted the fixator, leading to premature healing of the osteotomy. One patient ruptured the extensor pollicis longus. All complications resolved with additional intervention. Overall the patients showed radiographic and symptomatic improvement.

CONCLUSIONS

An external fixator and distraction lengthening through distraction osteogenesis is a viable alternative to plate fixation and bone grafting. In 18 of 20 of our patients, the technique eliminated the need for bone grafting and the need for a second surgical procedure to remove a dorsal plate.

Facial Nerve Paralysis

Distraction osteogenesis is a useful technique in temporomandibular joint reconstruction after gap arthroplasty for ankylosis. We report a case of unilateral facial nerve paralysis during the distraction phase of treatment in a patient with temporomandibular joint ankylosis who was treated with gap arthroplasty and distraction osteogenesis. The clinical course is described and discussed.

The effect of mandibular distraction osteogenesis on the histology and immunohistology of keratinized gingiva

OBJECTIVES

We investigated distracted keratinized epithelium to elucidate any proliferative and degenerated changes and to estimate the stability of the gingival tissues in mandibular distraction osteogenesis in a rabbit model.

STUDY DESIGN

Twenty-two rabbits were subjected to unilateral vertical osteotomy. After a latency period of 4 days, devices were activated 3, 6, and 10 days at a rate of 1 mm/day. We additionally investigated the recovery of the distracted gingiva in consolidation periods for 3 weeks. The animals were examined by histologic and immunohistologic methods using proliferating cell nuclear antigen (PCNA), single-stranded DNA (ssDNA), and keratin.

RESULTS

Atrophy of distracted gingiva was observed characterized by loss of rete ridges, acanthosis, vacuolation in the prickle cell layer, and cleavage of the keratin layer. Proliferating cell nuclear antigen-positive cells and ssDNA-positive cells were observed in the basal and prickle layers, respectively. During consolidation periods, slight recovery of rete ridges, thinning of the keratin layer, and immature epithelial layer was observed.

CONCLUSIONS

Proliferative and degenerated changes occurred to compensate for cell death and distracted space. Thickness of gingival tissues was maintained by high mitotic activity and delay in the rate of cell maturation. Immature epithelial layer was related to sensitive and weak resistance against various stimulating factors, such as cleavage of the keratin layer among distracted gingival tissues.

Treatment of Upper Airway Obstruction in Infants with Micrognathia Using Mandibular Distraction Osteogenesis

Mandibular distraction osteogenesis has become an accepted alternative treatment for infants and children with upper airway obstruction associated with micrognathia. Several reports exist that purport the efficacy of mandibular distraction in these patients, such as preventing tracheostomy or facilitating tracheostomy removal. However, the majority of these studies are retrospective reviews with small cohorts and relatively short-term follow-up. Consequently, the ideal indications, pre- and postoperative evaluation, timing, and treatment are subject to controversy and not currently well established. Significantly less attention has been given to short- and long-term complications of mandibular distraction, such as effects on the developing tooth buds, impact on future mandibular development, and temporomandibular joint abnormalities. This article reviews the basic principles of distraction osteogenesis, summarizes the outcomes of recent literature involving pediatric mandibular distraction including this author's experience, and discusses the known and potential adverse sequelae of mandibular distraction. Before a clearly defined role of mandibular distraction in the treatment of infants with micrognathia-associated upper airway obstruction can be established, additional prospective studies are necessary to delineate its benefits and limitations.

Rapid canine distalization through segmental alveolar distraction osteogenesis

OBJECTIVE

The objectives of this study were to achieve rapid canine distalization by segmental alveolar distraction method in first premolar extraction cases, to examine the changes in the periodontal tissues surrounding canines, to evaluate the displacement of the canine and first molar teeth, to assess the effects of the procedure on the pulpal vitality of the canines, and to determine the amount of root resorption in retracted canines.

MATERIALS AND METHODS

The sample of the study consisted of 20 teeth in eight patients (four females and four males, mean age 18.5 years). Pre- and posttreatment dental casts, panoramic radiographs, and standard periapical radiographs were taken from all patients. An electrical vitality test was applied before and after the distraction procedure and during the follow-up period (6 months after the completion of the procedure). In addition, six periodontal indices were used to examine the health of the periodontal tissues.

RESULTS

The distraction procedure was completed in 12 to 28 days (mean 14.65 +/- 3.49). The anchorage loss ranged from 0 to 3 mm (mean 1.2 +/- 0.83). The distal displacement of the canines ranged from 3 to 8 mm (mean 5.35 +/- 1.22). The canines showed a mean of 9.1 degrees distal tipping, whereas there was no statistically significant change in the axial inclinations of first molars after distraction.

CONCLUSION

We believe that rapid canine distalization by segmental distraction osteogenesis will become a routine protocol and a popular method among orthodontic applications.

Reactivation of trigeminal neuralgia following distraction osteogenesis in an 8-year-old child: report of a unique case

Trigeminal neuralgia is extremely rare in children. No concrete treatment protocols seem to be available for management of this condition in the pediatric population. Although trigeminal neuralgia may achieve remission, the possibility of reactivation of a hitherto quiescent condition cannot be ruled out. We present a case of pediatric trigeminal neuralgia following distraction osteogenesis of the mandible.

Rapid Canine Distalization through Segmental Alveolar Distraction Osteogenesis

OBJECTIVE

The objectives of this study were to achieve rapid canine distalization by segmental alveolar distraction method in first premolar extraction cases, to examine the changes in the periodontal tissues surrounding canines, to evaluate the displacement of the canine and first molar teeth, to assess the effects of the procedure on the pulpal vitality of the canines, and to determine the amount of root resorption in retracted canines.

MATERIALS AND METHODS

The sample of the study consisted of 20 teeth in eight patients (four females and four males, mean age 18.5 years). Pre- and posttreatment dental casts, panoramic radiographs, and standard periapical radiographs were taken from all patients. An electrical vitality test was applied before and after the distraction procedure and during the follow-up period (6 months after the completion of the procedure). In addition, six periodontal indices were used to examine the health of the periodontal tissues.

RESULTS

The distraction procedure was completed in 12 to 28 days (mean 14.65 +/- 3.49). The anchorage loss ranged from 0 to 3 mm (mean 1.2 +/- 0.83). The distal displacement of the canines ranged from 3 to 8 mm (mean 5.35 +/- 1.22). The canines showed a mean of 9.1 degrees distal tipping, whereas there was no statistically significant change in the axial inclinations of first molars after distraction.

CONCLUSION

We believe that rapid canine distalization by segmental distraction osteogenesis will become a routine protocol and a popular method among orthodontic applications.

The humerus is the best place for bone lengthening

The aim of this study was to examine the effectiveness of lengthening the humerus in children and young adults. Between 1984 and 2005, the Orthopaedic Department of Semmelweis University elongated 11 humeri (ten patients) for reasons of congenital hypoplasia (four cases), osteomyelitis (three cases), epiphyseolysis, growth plate closure after irradiation and obstetrical paralysis (one case each). The study cohort consisted of five females and five males, with an average age at the time of surgery of 17.8 years (range: 12-31 years). In every case, the lengthening was performed with a unilateral Wagner fixator. The lengthening protocol was 1 mm distraction daily (callotasis) after a 7-day latency period. The fixator was removed after total bone healing. Plate fixation or bone transplantation was not used. The average rate of lengthening was 6.2 cm (4.5-10.5 cm), and the achieved lengthening was 27% (range: 16-44%). The average healing index was 32 day/cm. One patient who suffered from temporary radial paresis, and temporary flexion contracture of the elbow was regarded as a complication following placement of the fixator. Based on our results, humeral shortening can effectively be treated with the unilateral Wagner fixator. The main difference between the original Wagner method and our approach is that we were able to leave the fixator in the humerus until total bony reconstruction so there was no need for plate fixation or bone transplantation.

Distraction vs remodeling surgery for craniosynostosis

OBJECTS

We designed several distraction devices and applied these instruments in 14 patients with varying types of craniosynostosis. The aim of this report is to clarify the advantages and disadvantages of these surgical methods and to discuss current concepts for the surgical strategy in the treatment of craniosynostosis.

METHODS

From January 2000 to July 2005, 28 patients with craniosynostosis were retrospectively analyzed. Surgical treatment was performed on 14 patients using the distraction method with internal distraction devices that we designed, in which 5 patients had plagiocephaly, 3 brachycephaly, and 6 scaphocephaly. All patients underwent preoperative and postoperative evaluations, which included the patient's neurological state, and three-dimensional CT.

RESULTS

With distraction devices, the time required for the surgery could be shortened almost 3 1/3 h; the bleeding during the surgery was decreased with reduced requirement of more than 200 ml of blood transfusion as compared with remodeling surgery. Postoperatively achieved distraction distances varied from 30.0 to 47.5 mm (mean, 42.99 mm). The average increased volume percent of cranium in distraction surgery group was 20.9% (range, -11.5 to 58.9%) after full distraction.

CONCLUSION

With distraction surgery, satisfactory cranial volume expansion and aesthetically pleasing morphological states were achieved in all cases, and the efficacy was statistically significantly high as compared with remodeling method.

Mandibular symphyseal distraction osteogenesis: review of three techniques

Mandibular symphyseal distraction osteogenesis (MSDO) is an alternative strategy to correct mandibular transverse deficiencies and dental crowding. Only a limited number of practitioners have reported their clinical experience and potential complications of this procedure to widen the mandible in a large case series. This study involved retrospective analysis of 40 patients who underwent mandibular symphyseal distraction osteogenesis. Three different types of distractor were used to widen the mandible: tooth-borne in 21 patients, bone-borne in 5 patients and hybrid (both bone and tooth-borne) in 14 patients. The distraction amount ranged from 7 to 11 mm (mean 7.31 mm). While 39 patients underwent successful mandibular symphyseal distraction, there was one failure. Most of the complications were experienced in bone-borne distractors, such as breakage of the distractor rod, gingival recession, secondary infection and ptosis of the chin. In the light of these findings, it is suggested that a lingually placed tooth-borne hyrax appliance is more suitable and reliable than the other distraction devices. Further larger studies are needed in order to better evaluate the effectiveness of bone-borne or hybrid devices.

Peri-Implant Bone Loss Around Posterior Mandible Dental Implants Placed After Distraction Osteogenesis: Preliminary Findings

BACKGROUND

The present study evaluates implant survival and peri-implant bone loss around posterior mandible dental implants placed at sites of distraction osteogenesis.

METHODS

On removal of the distraction devices, 34 dental implants were inserted into 14 posterior mandible sites in 10 healthy, non-smoking female patients. Prosthetic treatment was performed 4 months after implant placement using fixed implant prostheses. After 6 to 16.5 months, periapical radiographs were taken and evaluated for peri-implant bone loss and radiolucency. The distance between the implant margin and the first visible bone-implant contact was measured on the mesial and distal aspects of the implants using imaging software. Radiographic dimensional distortion was corrected as a function of the known true dimension of the implant.

RESULTS

Of the 34 implants placed, two (5.9%) failed to integrate at reentry surgery. Both were replaced and restored during the course of the study so that a total of 34 implants was followed for 12.1 +/- 3.8 months post-restoration and 16.1 +/- 3.8 months post-insertion. Mean loss of marginal bone height was 2.6 +/- 1.0 mm. During the follow-up period, radiolucent lines along the implant surface were absent.

CONCLUSIONS

The mean peri-implant bone loss in areas of alveolar bone distraction was 1.9 mm/year. A high implant survival rate was observed.

Complications in Alveolar Distraction Osteogenesis: A Clinical Investigation

PURPOSE

The purpose of this study was to evaluate distraction osteogenesis for reconstruction of vertically deficient alveolar ridges and to investigate the occurrence of complications during treatment and the effect of these complications on the final outcome.

PATIENTS AND METHODS

The study included 23 patients who underwent a total of 29 distraction procedures. Two types of distractors were used: intraosseous and juxtaosseous. All of the patients were submitted to the same distraction protocol. The complications occurring during treatment were classified as 1) intraoperative, 2) postoperative, 3) during distraction and consolidation, and 4) postdistraction.

RESULTS

The prevalence of cases with complications was 41.37% intraoperative, 24.13% postoperative, 65.51% during distraction and consolidation, and 58.62% postdistraction. Because many complications coincided in some patients, the overall prevalence throughout the treatment was 79.31% of cases; 3.44% of the complications jeopardized subsequent implant placement.

CONCLUSIONS

Although a high frequency of complications was encountered, severe complications were rare. Most of the complications had simple solutions, and most did not jeopardize the final outcome. Distraction osteogenesis is a viable option for treating vertical alveolar bone defects.

Histological evaluation of the temporomandibular joint after bilateral vertical ramus mandibular distraction in a canine model

The aim of this pilot study was to histologically evaluate the effect of bilateral vertical mandibular distraction osteogenesis (DO) on the temporomandibular joint (TMJ) in a canine model. Eight male beagle dogs underwent DO, with the placement of single-vector internal distractors. One unoperated animal served as control. After a latency period of 7 days, distraction was performed at a rate of 1 mm a day for an average of 12 days. The animals were divided into two groups (n = 4) and sacrificed after one or two months of consolidation. Eighteen TMJs were prepared for histological evaluation. Control TMJs surfaces were smooth, with no irregularities and trabecular bone was thick and multiply connected. In the one-month group, thinning of the trabecular bone was evident. The trabeculae were long, not multiply connected, parallel to each other and perpendicular to the articular surface. Although overall fibrous-cartilaginous tissues covering the TMJs were maintained with no signs of degenerative changes, one condyle from the one-month group had depressions and erosions of the fibro-cartilage layer and subcortical bone. In the two-month group, overall bone and cartilage architecture was more similar to the control specimens. This study indicates that, in the short term, gross changes can occur in the TMJ after bilateral mandibular vertical ramus distraction. These changes seem to be a process of biological adaptation to the pressure and functional changes secondary to surgery and distraction. However, long-term studies are needed to confirm whether the changes are completely reversible.

Condylar mineralization following mandibular distraction in rats

The impact of mandibular distraction on condyles is poorly understood. To examine how condylar mineralization is affected, we performed distraction in 128 one-month-old rapidly and 126 three-month-old slowly growing rats. The rate of distraction was 0.0 mm (sham), 0.2 mm (slow), 0.4 mm (moderate), or 0.6 mm (rapid). From 7 to 9 rats from each rate (n = 29-32) were killed at 4 time periods (D6, D10, D24, and D38) following osteotomy. Calcein and alizarin were injected 6 and 3 days, respectively, prior to death. Methacrylate-embedded sagittal condylar sections were examined under epifluorescence, and mineral apposition rates were measured. Results indicated that: (1) rapidly growing rats showed higher mineral apposition rates (p < 0.01-0.001) than did slowly growing rats; (2) mineral apposition rates were lower in distracted sides at all times in rapidly growing rats (p < 0.05-0.01), while this side-dependency was seen only at D24 in slowly growing rats (p < 0.05); and (3) distraction rates had little effect on mineral apposition rates. Thus, mandibular distraction decreases condylar mineral apposition rates, but only in rapidly growing rats, which is related to surgery and its functional consequences, not to the distraction rate.

Bone defect formation during implant placement following alveolar distraction

PURPOSE

This retrospective study was designed to evaluate the volume of hard tissue generated at the time of implant placement in distracted alveolar bone.

MATERIALS AND METHODS

All patients who underwent distraction osteogenesis between 2000 and 2003 were included. The preoperative bone height, amount of distraction performed, and presence or absence of complications affecting implant placement were recorded. The augmentation achieved was correlated with insufficient bone formation using the Spearman correlation and the Fisher exact test.

RESULTS

The study included 43 implants placed in 17 cases of alveolar distraction. Of the 34 implants placed in bone augmented by 4.5 to 6.5 mm, bone defects were observed with 12. All 9 implants placed in ridges augmented by 7 to 10.5 mm demonstrated a bone defect. The "defect" and "no-defect" implant groups differed significantly with respect to preoperative bone height and amount of distraction performed (P < .001 for both). Significantly more defects were formed in bone augmented by > 25% compared to bone augmented by < 25% (P < .001).

CONCLUSIONS

When considering distraction osteogenesis, augmentation of up to 25% of the initial bone height seems more predictable and less likely to be associated with complications at the time of implant placement. In distractions greater than 25% of the original height, additional treatment should be considered.

A retrospective study of the potential complications during alveolar distraction osteogenesis in 55 patients

The aim of this retrospective study was to analyse the outcome of alveolar distraction osteogenesis for the correction of vertical defects in a large series of 55 cases. The existing bone deficiencies were secondary to atrophy after periodontal disease or tooth extraction. The overall success rate of this technique was 89.1%. The complications presented during treatment were divided into minor (no effect on final result, but immediate intervention required) 14/55 patients (25.4%), and major (lead to technique failure) 6/55 patients (10.9%). The frequency of minor complications was 8/27 in the anterior maxillary region, 1/27 in the anterior mandibular region and 15/27 in the posterior mandibular region. The frequency of major complications was 5/6 in the posterior mandibular region and 1/6 in the anterior maxillary region. The mean alveolar height achieved was 6mm. The overall rate was 36.3%. On the basis of these results it was concluded that alveolar distraction osteogenesis is an effective technique to treat vertical alveolar ridge deficiencies.

Bone lengthening in children: how to predict the complications rate and complexity?

PURPOSE

Complications arising from limb-lengthening procedures are often severe leading to long-term residuals. The aim of this study was to determine whether the complication rate and complexity could be predicted using a distraction index for bone lengthening in children.

STUDY DESIGN

This study retrospectively reviewed a series of 116 lower limbs lengthening in 88 consecutive patients (mean age 13.5). Mean follow-up 3.8 years. Lengthening percentage, lengthening index, distraction regenerate length, additional surgeries, and complications rate were used to evaluate the results of limb lengthening. The correlation between lengthening percentage and complication rate was particularly analyzed and its practicability illustrated. Scatter plots of complication rate (%) against lengthening percentage were constructed, and linear regression was used to investigate mathematical relationship between the variables.

RESULTS

The lengthening index was 33 +/- 12.1 days/cm. The length of distraction regenerate was 6 +/- 3.2 cm. The lengthening percentage was 21 +/- 16.5. The scatter plots of neurological complication rate, residual deformities rate, broken pins rate, joint contractures rate, and hypertension rate against lengthening percentage showed a positive linear relationship with r = 0.8.

CONCLUSIONS

The number of complications increased considerably with the increase in lengthening percentage. The lengthening percentage correlates very well with the complication rate and can be used to predict the complication rate.

CLINICAL RELEVANCE

During planning a lengthening procedure, the lengthening percentage should be a useful tool to predict the complications rate and to discuss the risks and benefits with patients and their families. The knowledge about predictable complications should help prevent and early detect expected complications.

The Use of Internal Maxillary Distraction for Maxillary Hypoplasia: A Preliminary Report

PURPOSE

Distraction osteogenesis is a useful alternative to advance the maxilla in complicated cases of maxillary hypoplasia. The purpose of this article is to review the workup, experience, and preliminary results with the use of internal distraction osteogenesis for maxillary hypoplasia at one teaching institution.

PATIENTS AND MATERIALS

Over a 5-year period, more than 300 patients with craniofacial and dentofacial defects have undergone oral and maxillofacial surgery at our center to correct their skeletal discrepancies. Of these, 10 have had maxillary distraction osteogenesis done with internal distractors. Follow-up of 6 months or more was available for 8 patients. Stereolithographic models were used to bend distractors prior to surgery in 6 patients.

RESULTS

Latency prior to the start of distraction was 3 to 7 days and varied with the age of the patient. Distraction occurred at approximately 1 mm per day with an average distraction length of 8.5 mm (range, 6-10 mm). Excellent occlusal results were obtained in 5 patients. Major complications including nonunion and failure to achieve acceptable occlusal results were observed in 3 patients. Minor complications including pain and loosening of the distracter devices were observed in 2 patients, but did not appear to affect the esthetic and functional results.

CONCLUSIONS

Distraction osteogenesis is a useful alternative to traditional orthognathic surgery to treat maxillary hypoplasia. Internal distractions are attractive to patients, but are more difficult to place and can cause discomfort to patients when trying to achieve an ideal primary vector of distraction. Stereolithographic models can help with placement of the device. Changes in design of distractors may help with patient discomfort.

Monobloc Advancement by Distraction Osteogenesis Decreases Morbidity and Relapse

BACKGROUND

Treatment of midface hypoplasia and forehead retrusion with monobloc advancement is associated with significant complications, including meningitis, prolonged intubation, and frontal bone flap necrosis. To see whether distraction of the monobloc segment offered decreased morbidity, the authors compared clinical outcomes of patients who underwent conventional monobloc advancement with those of patients who underwent monobloc distraction.

METHODS

Group 1 (conventional monobloc; n = 12) underwent traditional monobloc advancement with bone grafting. Group 2 (modified monobloc; n = 11) did not receive ventriculoperitoneal shunts and underwent the above procedures with placement of a pericranial flap and fibrin glue over the midline defect. Group 3 (monobloc distraction; n = 24) underwent advancement of the monobloc segment by distraction osteogenesis using internal distraction devices. Complications included meningitis, cerebrospinal fluid leak, frontal bone flap loss, and wound infection. Preoperative, postoperative, and follow-up lateral cephalograms were used to assess horizontal changes of the forehead, midface, and maxilla.

RESULTS

Group 3 (distraction monobloc) had the lowest complication rate (8 percent), followed by groups 2 (modified monobloc; 43 percent) and 1 (conventional monobloc; 61 percent) (p < 0.05). Group 3 achieved greater advancement (12.6 mm) than did group 2 (9.4 mm) or group 1 (9.1 mm) (p < 0.05). Relapse was least in group 3 (8 percent) compared with groups 2 (67 percent) and 1 (45 percent).

CONCLUSIONS

Monobloc advancement by distraction osteogenesis had less morbidity and achieved greater advancement with less relapse compared with conventional methods of acute monobloc advancement with bone grafting. Monobloc distraction is superior to conventional methods of acute monobloc advancement and is an alternative to staged fronto-orbital advancement followed by Le Fort III advancement.

Unexpected breakage of mandibular midline distraction device: case report

Management of the transverse mandibular deficiency and anterior crowding by mandibular midline distraction osteogenesis (MMDO) is an efficient and stable alternative to orthodontic mechanics with minor complications. Although the only major complication reported previously during MMDO is the nonunion of the segments, in the present case report an unexpected breakage of the distractor in MMDO during the consolidation period as a new major complication was presented.

Knee arthritis in congenital short femur after Wagner lengthening

Knee anomalies are common in patients with congenital short femurs who require lengthening to correct limb-length discrepancies. We retrospectively reviewed the incidence of knee arthritis and the factors influencing its occurrence after femoral lengthening using the Wagner method. Twenty-three patients with congenital short femurs treated with the Wagner method were followed up until skeletal maturity (minimum, 5 years postoperatively). The mean age of the patients at lengthening was 10.8 years (range, 8.4-14.5 years). The mean leg-length discrepancy at the time of surgery was 9.7 cm (femur, 7.6 +/- 3.7 cm; tibia, 2.1 +/- 1.8 cm). Femoral lengthening (mean, 7.9 cm) was performed in 17 patients. Femoral lengthening and tibial lengthening were performed simultaneously in six patents (mean, 11.8 cm). The mean age of the patients at the last followup was 16.8 years (range, 14-20.3 years). Eighteen patients had arthritis at followup. Nine patients had severe arthritis develop, seven of whom had knee instability preoperatively and temporary subluxation during the lengthening procedure. Seventy-eight percent of patients had arthritis develop in the knee after lower-limb lengthening using the Wagner method for congenital short femurs. Patients who had an unstable knee before surgery had temporary knee subluxation develop during the lengthening procedure, and patients who had simultaneous lengthening of the femur and tibia had a high association with degenerative arthritis changes in the knee.

Complications in maxillary distraction using the RED II device: a retrospective analysis of 21 patients

Rigid external distraction osteogenesis (DO) in the treatment of midface hypoplasia has been shown to be effective and safe, but there have been several case reports on complications. Here is presented an overview of the complications in a series of 21 patients with various craniofacial anomalies. All patients were treated using the rigid external distraction II (RED II) device after Le Fort I or III osteotomy. Distraction started 1 week postoperatively and continued until Class I occlusion was achieved; it was then continued to include a 15% overcorrection. All data were collected and categorized retrospectively from the patients' files. After a mean period of distraction of 34 days, 42 complications were reported in six different categories. Pin loosening (42.9%) and frame migrations (28.6%) were the most common complications. Of the frame migrations 25% were traumatic. Intracranial penetration of one fixation pin occurred during removal of the RED II device in one patient. From these results it can be deduced that application of the RED II device is associated with a substantial number of specific complications that mainly concern the pins of the halo-frame. The stability of the device is discussed as the distraction distance achieved was less than expected.

The effect of tibial lengthening on immature articular cartilage of the knee joint

OBJECTIVE

To investigate the acute response of immature articular cartilage, in the distraction and consolidation phases, to 30% tibial lengthening.

DESIGN

Sixteen immature New Zealand white rabbits underwent diaphyseal lengthening of the left tibia by callotasis at a distraction rate of 0.4mm twice daily. A sham control group of 12 rabbits underwent fixation and osteotomy without lengthening. In each group, half of the rabbits were killed at the end of the distraction phase or at an equivalent time period and the rest were killed after an additional 5 weeks (consolidation phase). The tibial condyles and synovial fluid in the knee joint cavity were taken for laboratory examination. Sulfated glycosaminoglycan in synovial fluid was estimated using a colorimetric method. Sections along the mid-coronal plane of the whole of the tibial condyles were examined histologically and by scanning electron microscopy. A grading system was used to make a semiquantitative assessment of the histopathological changes in articular cartilage.

RESULTS

Damage to the immature articular cartilage had occurred by the end of the distraction period and the cartilage continued to deteriorate in the consolidation phase of 5 weeks. However, when compared with a similar study in a mature rabbit model, damage to immature cartilage appeared less severe.

CONCLUSION

This model of 30% lengthening caused acute cartilage damage which did not recover in the short term. The result may have implications for longer lengthening in children; the effects may be disadvantageous and lead to degenerative diseases later in life.

[Vertical distraction osteogenesis of the extremely resorbed edentulous mandible. A retrospective description of 16 patients]

This study's objective is to assess long-term results of vertical distraction osteogenesis for the extremely resorbed edentulous mandible by clinically measuring and taking x-rays from the beginning of the treatment of 16 subsequent patients to its final moment in the follow up period (ranging from 2-62 months). Bone height, nerve sensitivity, complications and loss of implant were registered. Average bone resorption after 3 years was 11.2%. Out of 16 patients 5 experienced sensory nerve disturbance; 3 suffered complications. The implant success rate was 89.2%. Distraction osteogenesis appears to be a reliable technique, with which stable bone tissue is developed. Risk of sensory nerve disturbance and complications however, must be taken into consideration.

Pediatric Feeding Disorder and Growth Decline following Mandibular Distraction Osteogenesis

BACKGROUND

Mandibular distraction osteogenesis has proven to be an effective treatment for upper airway obstruction related to micrognathia. Changes in the aerodigestive space can help facilitate tracheostomy removal in children and prevent tracheostomy in newborns. However, this may also precipitate changes in the ability to orally feed. There are few data on early postoperative feeding and growth rate following mandibular lengthening. The authors found evidence of growth rate decline and feeding difficulty in pediatric patients following mandibular distraction osteogenesis.

METHODS

Ten pediatric patients underwent mandibular distraction osteogenesis for treatment of upper airway obstruction. Outcomes in resolution of upper airway obstruction, oral feeding success, and growth rate were analyzed. Follow-up ranged from 12 to 28 months.

RESULTS

All 10 patients had complete resolution of upper airway obstruction. The length of distraction ranged from 10 to 17 mm. Three patients demonstrated a feeding disorder after mandibular distraction osteogenesis, defined as requiring a long-term (>1 month) alternate feeding method (gastric tube in two patients and gastric gavage in one). Seven of 10 patients exhibited an early decline in growth rate following distraction. Data used to determine growth rate changes were weight measurements at the time of distraction, at the time of distractor removal (6 to 8 weeks after distraction), and at 6 and 12 months after the date of distraction initiation.

CONCLUSION

These results suggest that infants and children undergoing mandibular lengthening by distraction osteogenesis should be carefully monitored for postdistraction feeding disorder and growth rate disturbance.

Expression of nerve growth factor and vascular endothelial growth factor in the inferior alveolar nerve after distraction osteogenesis

The objective of this study was to evaluate changes occurring in the inferior alveolar nerve (IAN) subsequent to mandibular distraction osteogenesis, with regard to the expression of nerve growth factor (NGF) and vascular endothelial growth factor (VEGF). Unilateral mandibular distractions (0.5mm each, twice per day for 10 days) were conducted on 8 mongrel dogs. Two animals were killed at 7, 14, 28 and 56 days after completion of distraction. The distracted IAN and contralateral control nerve were then harvested and analysed histologically and immunohistochemically. Signs of acute nerve injury, including demyelination, were observed in the distracted IAN on the 7th and 14th day after distraction. At 56 days, the histological features of the distracted IAN were similar to those of the control nerve. The levels of NGF and VEGF expression were significantly elevated on the 7th and 14th day after distraction. NGF was expressed in most of the distracted nerve tissues, but VEGF was primarily detected in Schwann cells and the neurovasorum. VEGF expression had returned to normal but NGF expression was still profoundly elevated 28 days after distraction. NGF expression returned to normal levels at 56 days after distraction. NGF and VEGF appeared to have been elicited from the Schwann cells and damaged nervous tissues, and they may play important roles in the initial healing of damaged nerves. VEGF expression returned to normal more quickly than did NGF expression. This may indicate that hypoxic conditions within the distracted nerve had recovered to normal during the early stages of consolidation. Micro-vessels in the distracted nerve may have recovered more rapidly than did the nerve tissue itself.

Deformity correction by external fixation and/or intramedullary nailing in hypophosphatemic rickets

BACKGROUND

There are many modalities of treatment for complex lower extremity deformity in hypophosphatemic rickets. We evaluated the outcomes of deformity correction using an external fixation and/or intramedullary nailing in hypophosphatemic rickets.

PATIENTS AND METHODS

55 segmental deformities (20 femora, 35 tibiae) from 20 patients were examined retrospectively. There were 9 children and 11 adults. Distraction osteogenesis was used in 28 segments and acute deformity correction in 27. External fixation was applied in 24 segments, intramedullary nailing in 6, and external fixation and intramedullary nailing in 25.

RESULTS

There were 18 major and 13 minor complications in 26 of 28 segments with distraction osteogenesis, and 13 major and 10 minor complications in 19 of 27 segments with acute correction. Recurrent deformity or refracture occurred in 10 of 21 segments with distraction osteogenesis by external fixation only, 4 of 6 with acute correction by intramedullary nailing, and 1 of 25 with distraction osteogenesis or acute correction by external fixation and intramedullary nailing. Nail-related complications occurred in 3 of 6 with intramedullary nailing and 2 of 25 with external fixation and intramedullary nailing.

INTERPRETATION

External fixation and intramedullary nailing can be recommended to prevent complications during or after deformity correction in hypophosphatemic rickets.

Limb lengthening in fibular hemimelia type II: can it be an alternative to amputation?

The purpose of our study was to analyze limb lengthening in fibular hemimelia type II. Ten patients underwent 16 tibia lengthenings. The mean tibia shortening was 5.8 cm. We used the Ilizarov technique in all cases. The mean follow-up time was 7.2 years. The mean lengthening was 23% of the former length. The healing index was 50.8 days/cm. In the final examination six patients were skeletally mature, equal limb length and functional foot positioning were achieved in four of them. Complications were observed during 14 lengthenings (87.5%). Although lengthening in fibular hemimelia is difficult, elongation with axis and foot correction may offer an alternative to amputation.

Adult acquired flexible flatfoot, treated by calcaneocuboid distraction arthrodesis, posterior tibial tendon augmentation, and percutaneous Achilles tendon lengthening: a prospective outcome study of 20 patients

BACKGROUND

Several methods for the treatment of acquired flexible flatfoot have been described.

PATIENTS AND METHODS

We followed the outcome of calcaneocuboid distraction arthrodesis with lengthening of the lateral column prospectively in 20 patients (20 feet). The mean age of the patients was 55 (30-66) years and 16 were women. The lateral column lengthening was combined with percutaneous lengthening of the Achilles tendon and augmentation of the posterior tibial tendon in all patients. Fixed forefoot supination, hallux valgus, and/or symptomatic arthrosis, were corrected with arthrodesis of the first cuneiform-metatarsal joint (n = 8) and arthrodesis of the naviculocuneiform joint (n = 2). The Foot Function Index (FFI) and American Orthopedic Foot and Ankle Society (AOFAS) Clinical Rating Index hindfoot score (CRI) were completed preoperatively and at follow-up. Follow-up time was 25 (13-39) months. All patients were physically examined at follow-up at the outpatient clinic, and the overall satisfaction rate was registered. Standardized weight-bearing radiographs were taken preoperatively and at follow-up. The lateral and dorsoplantar talometatarsal angle was measured, together with the ground-navicular distance.

RESULTS

At follow-up, 17/20 feet had complete relief of pain or only minor symptoms. The overall patient satisfaction rate was excellent or good in 15 patients and 17 patients reported an increase in daily and/or recreational activities. 3 patients complained of pain at the distraction site and/or cuboid-MT5 joint, without signs of arthrosis. All but 1 patient would have chosen to undergo the same procedure given the same circumstances. The improvement in both the FFI and CRI was statistically significant. On radiographic examination, the lateral and dorsoplantar talometatarsal angle and the ground-navicular distance improved significantly. Nonunion developed in 2 patients and united after bone grafting. 3 patients had either paresthesia or anesthesia in the distribution area of the sural nerve.

INTERPRETATION

We found good short-term results after calcaneocuboid distraction arthrodesis, percutaneous tendon Achilles lengthening, and medial soft tissue augmentation for the treatment of degenerative/acquired flexible flatfoot. Pain or discomfort along the lateral aspect of the foot is the most common and worrying postoperative complaint.

An unusual complication of mandibular distraction

BACKGROUND

The authors present an unusual complication of mandibular distraction in a child with the curious condition of multiple pterygium syndrome is presented.

CASE REPORT

The patient was a Caucasian male with severe pterygia in his neck. As a result of his limited mouth opening and restricted upper airway leading to obstruction, he underwent lengthening of his mandible by distraction, which significantly improved his breathing. During his follow-up, it was observed that an unusually elongated permanent molar was present in an abnormal position.

CONCLUSION

This case highlights the need to carefully plan the sites for osteotomy and the potential for damage to the developing permanent dentition in young children.

[Analysis of the complications following mandibular distraction using internal distractors]

OBJECTIVE

To investigate the causes and the prophylactic for the complications following mandibular distraction osteogenesis using internal distractors.

METHODS

From 1997 to 2004, a total of 46 patients (61 sides) suffering from malformations or defects of mandible who underwent mandibular distraction osteogenesis were analyzed. The diseases included hemifacial microsomia in 27 cases, congenital or acquired mandibular hypoplasia and micrognathia bilateral in 8 cases and unilateral in 4 cases, electronical injury or postoperative mandibular defects in 3 cases, Treacher Collins syndrome in 2 cases, obstructive sleep apnea syndrome in 2 cases.

RESULTS

Of them, 9 patients had postoperative complications, which included 3 patients had complications associated with distractors, local infection occurred in 2 cases, apertognathia of anterior teeth in 2 case, 2 patients had sinus of the skin of the lower lip. 9 patients had been aggressivly managed and obtained satisfactory results.

CONCLUSIONS

The pivotal points to reduce complications are to understand the mechanism of mandibular distraction osteogenesis completely, and to be familiar with the anatomy of mandible and adjacent tissues. It is necessary to treat with it preoperatively and postoperatively.

Operative lengthening of the humerus: indications, benefits, and complications

The purpose of this study was to determine the benefits and risks of humeral lengthening procedures. Distraction osteogenesis was performed in 19 humeri on 16 patients (9 males, 7 females). The mean age at the time of lengthening was 11.5 years (range 3-24 years) and average follow-up was 8.7 years (range 2-21 years). Etiologies for short humeri included infection in six patients, congenital anomaly in six patients, unicameral bone cysts involving the physis in five patients, and posttraumatic growth disturbance in two patients. The average lengthening was 5 cm. The benefits from humeral lengthening include increased performance in daily activities, improved sports performance, and significantly better self-image. Complications included temporary radial nerve palsy in three cases, drainage from the pin tracts in two cases, elbow flexion contracture in three cases, and late humerus fracture in two cases. All the complications resolved over time and did not affect the outcome. Eleven lengthening procedures were not associated with any complications. Although the humerus is surrounded by complex neurovascular structures and muscles, humerus lengthening provided satisfactory results with temporary minor complications.

Unilateral humeral lengthening in children and adolescents

This study evaluates our early experience with unilateral humeral lengthening in children and adolescents. From 1995 till 2001, 16 cases with unilateral humeral shortening ranging from 5.5 to 15 cm were referred to our center. The cause was Erb's palsy in eight cases, epiphyseal injury in five cases and infection in three cases. The average age at operation was 13 years (range 8.5-17 years). Hybrid fixation using wires and half pins were applied to all cases to minimize the risk of operative neurovascular complications. Osteotomy was performed in the middle third of the humerus through a posterior approach. After a latent period of 5-7 days lengthening started at a rate of 0.33 mm every 8 h. At an average follow up of 3 years and 2 months (range 1 year and 4 months to 5 years and 6 months) there were 10 excellent and six good results. The average healing index was 28 days/cm. Complications included pin tract infection in all cases; radial nerve palsy in one patient whose humerus overlengthened by 2 cm but improved completely after compression; fracture of the regenerate in two cases.

Distraction osteogenesis with subperiosteal devices in edentulous mandibles

Nine patients with severely atrophic edentulous mandibles were treated by distraction osteogenesis with subperiosteal distractors for vertical augmentation of the anterior alveolar bone before insertion of implants. All the patients had severe complications and we conclude that the use of subperiosteal devices for vertical augmentation of edentulous mandibles is hazardous and offers no advantage over other surgical methods.

Anterior transmandibular osteodistraction: clinical and model observations

INTRODUCTION

The aim of this paper was to study the effect of transmandibular distraction on the periodontal and dental structures, and the initial movements of the mandibular halves, when using an axial plane non-rigid bone-borne distractor (TMD).

MATERIAL AND METHODS

Fourteen patients undergoing bimaxillary transverse osteodistraction had their six lower anterior teeth assessed for mobility, sensitivity, and pocket depth. Recordings were made pre-operatively, post-distraction, post-consolidation and at 1-year follow-up. Selected landmarks on pre-operative and post-consolidation models were also digitised in three dimensions to study individual tooth movements, and positional changes of the mandibular halves.

RESULTS

Pockets depths around the incisor teeth increased during the consolidation period (probably due to reduced oral hygiene), but returned to normal by the 1-year post-operative consultation. Tooth mobility increased temporarily in the active phase (central incisors, lateral incisors) and in the consolidation phase (lateral incisors, canine teeth). Sensitivity to cold was temporarily lost in the incisor teeth, probably as a result of 'apical contusion'. One central incisor was inadvertently apically osteotomized and needed root canal treatment. The angle between the mandibular halves closed by 9.4 degrees.

CONCLUSION

Periodontal and dental morbidity is transient and limited to the distraction and consolidation period, as long as the tooth apices are avoided when the osteotomy is performed. A step-design osteotomy may be preferable when the central incisor apices are close to each other. The transmandibular distractor (TMD) allows for rotation at the temporomandibular joints.

Analysis of complications following alveolar distraction osteogenesis and implant placement in the partially edentulous mandible

OBJECTIVE

The purpose of this retrospective study was to evaluate complications before, during, and after vertical alveolar distraction osteogenesis and to assess the survival rate of dental implants placed in distracted bone.

STUDY DESIGN

In a consecutive series, 37 patients with 45 alveolar ridge deficiencies of the partially edentulous mandible were treated with 14 intraosseous and 31 subperiosteal distraction devices. Seventy-two dental implants could be placed at the time of distractor removal and 21 implants at a second stage.

RESULTS

Complications associated with the distraction procedure affected 75.7% of patients. The majority of complications were of minor nature with the exception of fractures of basal bone (n = 3), fracture of transport segment (n = 1), breakage of distractor (n = 1), and severe mechanical problems (n = 3). Eleven secondary grafting procedures were necessary to allow the placement of dental implants. Implant survival was 95.7% (mean postloading follow-up: 35.7 months).

CONCLUSION

Vertical alveolar distraction osteogenesis is not an uncomplicated procedure; however, long-term survival of dental implants inserted into distracted areas is satisfactory.

Transverse maxillary distraction with a bone-anchored appliance: dento-periodontal effects and clinical and radiological results

In 29 adult patients presenting with maxillary deficiency, a bone-anchored palatal distractor (Surgi-Tec NV, Brugge, Belgium) was applied after osteotomy of the anterolateral walls of the maxillary sinuses, midpalatal suture, and, eventually, separation of the pterygomaxillary sutures. Expansion proceeded at a rate of 0.33-0.66 mm per day and the device was retained for 4-6 months for consolidation. Active orthodontic therapy was started after 8-10 weeks. The increment of arch width and the perimeter were evaluated using dental casts. Tooth thermal sensitivity and the periodontal side effects of treatment were monitored clinically after distraction, at device removal, and after 1 year. Bone healing was also investigated during the procedure using conventional radiological techniques. This experience confirms that transverse maxillary distraction is an effective technique in adult patients, leading to the formation of new bone. There were no noticeable intraoperative complications, but postsurgical periodontal side effects were documented. The procedure offers advantages over traditional teeth-borne appliances in terms of rapidity of treatment and the absence of mechanical forces acting on the teeth. Further evaluation is required to assess the long-term stability and periodontal consequences of this technique.

Reconstruction with Distraction Osteogenesis for Juxta-articular Nonunions with Bone Loss

BACKGROUND

Nonunions of a juxta-articular lesion with bone loss, which represent a challenging therapeutic problem, were treated using external fixation and distraction osteogenesis.

METHODS

Seven juxta-articular nonunions (five septic and two aseptic) were treated. The location of the nonunion was the distal femur in four patients, the proximal tibia in one patient, and the distal tibia in two patients. All of them were located within 5 cm from the affected joints. Preoperative limb shortening was present in six cases, averaging 2.9 cm (range, 1-7 cm). The reconstructive procedure consisted of refreshment of the nonunion site, deformity correction, stabilization by external fixation, and lengthening to eliminate leg length discrepancy or to fill the defect. Shortening-distraction was applied to six patients and bone transport to one patient for reconstruction. Intramedullary nailing to reduce the duration of external fixation was simultaneously performed in two cases. All the patients had at least 1 year of follow-up evaluation.

RESULTS

Osseous union without angular deformity or leg length discrepancy greater than 1 cm was achieved in all patients. The mean amount of lengthening was 5.8 cm (range, 2.2-10.0 cm). The mean external fixation period was 219 days (range, 98-317 days), and the mean external fixation index was 34.4 days/cm (range, 24.5-47.6 days/cm). All patients reported excellent pain reduction. There were no recurrences of infection in five patients with prior history of osteomyelitis. The functional results were categorized as excellent in two, good in three, and fair in two.

CONCLUSION

Despite the length of postoperative external fixation, distraction osteogenesis can be a valuable alternative for the treatment of juxta-articular nonunions.

Prevention of halo pin complications in post-cranioplasty patients

INTRODUCTION

Distraction Osteogenesis has been successfully implemented in the treatment of maxillary hypoplasia. By using the Rigid External Distraction device (RED) the maxilla can be advanced without the need for bone grafts, providing more stability to the repositioned maxilla.

BACKGROUND

The introduction of the RED system in craniofacial surgery has given rise to previously unseen problems.

AIM

To provide a set of protocol improvements that might prevent the intracranial pin migration seen at the removal of a RED-II in one patient.

CONCLUSIONS

Although the RED device has been shown to achieve good clinical results, there are some disadvantages to the system. There is a high incidence of pin tract infections - leading to loosening of the pins and loss of rigidity. Also, the external ring is prone to traumatic injury. Furthermore, the positioning of the pins can be difficult in thin bone. The improvements used in our protocol might prevent this complication.