Oral and dental restoration of wide alveolar cleft using distraction osteogenesis and temporary anchorage devices

Outcomes of Bifocal Transport Distraction Osteogenesis for Repairing Complicated Unilateral Alveolar Cleft

OBJECTIVES

This study aimed to assess the outcomes of bifocal transport distraction osteogenesis (BTDO) for closure of a wide or previously failed unilateral alveolar cleft.

METHODS

Patient in this study had a large alveolar cleft that had not healed with bone grafts. Bone-borne distraction was used under general anesthesia. Intraoperative complications as bleeding and trauma to neighboring teeth were documented. Postoperative complications as wound dehiscence, paresthesia, infection, and bleeding were recorded. Complications including changes in bone segment movement, activation force loss, and occlusal interferences were observed during the activation phase. During the consolidation phase, problems including gingival recession, pulpal vitality, and cosmetic concerns were evaluated. Postoperative, periapical, occlusal, and orthopantomograms were used to evaluate bone gain and bone generation in the distracted area.

RESULTS

Ten patients (6 males and 4 females) with unilateral alveolar cleft were included, with mean age of 9.5 ± 2.5 years. Average cleft width was 12.25 ± 2.54 mm. There was no intraoperative or postoperative bleeding. Only 1 patient had a wound dehiscence (10%). All patients had mild postoperative pain and edema in upper lip. Only 1 patient complained of numbness in infraorbital nerve's innervated region. Radiographs revealed bone formation in cleft area and bone healing in distracted chamber.

CONCLUSIONS

Bifocal transport distraction osteogenesis improves success rate of an alveolar cleft treatment especially a wide or previously failed one. This technique associated with minimal complications when careful planning and cooperation from a patient are combined. It can be recommended when other modalities for alveolar cleft are failed. Patients also tolerate the device well.

Alveolar Distraction

Alveolar distraction osteogenesis (ADO) has been used for the reconstruction of atrophic alveolus for decades. The advantage of this technique is that it augments the bone and soft tissues together, creating a better alveolar platform for subsequent surgeries and dental rehabilitation. It is especially useful in patients with large and/or complex alveolar clefts for which approximating the alveolar segments reduces the size of the bony cleft and associated fistula. Displacement of the transported segment is the most frequently encountered complication of ADO but can be managed by constructing case-specific distractors.

Horizontal alveolar transport distraction osteogenesis followed by implant placement

Alveolar transport distraction osteogenesis (ATDO) is an alternative treatment method to vertical alveolar distraction osteogenesis in cases of large bony defects, especially when the bone is limited in size. ATDO was performed in 10 patients with 12 defects. The mean age of the patients was 39.1years. The average bone length gain was 18.2mm. Implants were inserted following a 3-month consolidation period. Three patients needed additional bone grafting for horizontal widening. Final prosthetic rehabilitation was performed at least 3 months following implant insertion. The mean follow-up period was 63 months and the survival rate of the 25 implants placed was 92%. All failures (n=2) occurred during the early healing period. Although the results are not totally predictable, it can be concluded that ATDO can be effective in the reconstruction of the alveolar crest prior to implant placement.

Management of Severely Atrophic Maxilla in Ectrodactyly Ectodermal Dysplasia-cleft Syndrome

Background:

Ectrodactyly ectodermal dysplasia-cleft syndrome is a rare genetic syndrome with an incidence of 1/90,000 live births, characterized by cleft lip and palate, severely hypoplastic maxilla, and hypodontia. Patients diagnosed with ectrodactyly ectodermal dysplasia-cleft syndrome suffer from a severely hypoplastic maxilla that is highly difficult to treat using traditional orthognathic methods. In this study, we propose using distraction osteogenesis to achieve a major advancement while maintaining good stability and minimal relapse. To our knowledge, this is the first description of patients with this syndrome treated using distraction osteogenesis.

Methods:

Five patients diagnosed with ectrodactyly ectodermal dysplasia-cleft syndrome were included in the study. All patients had been operated on according to the well-established protocol of cleft lip and palate reconstruction before maxillary distraction osteogenesis. Hard and soft-tissue changes were evaluated by cone beam computed tomography and lateral cephalograms before distraction osteogenesis (T1), at the postdistraction point (T2) and after 1 year of follow-up (T3).

Results:

Examination revealed marked maxillary advancement in all our patients with a significant mean difference in hard tissue parameters (condylion to A point = 18 mm; nasion-sella line to A point = 15.2 degrees) and a notable improvement in facial convexity (20.9 degrees). One year follow-up measurements demonstrated mild relapse rates of 6% in the horizontal plane.

Conclusions:

We conclude that despite the challenging anatomic and physiological features of ectrodactyly ectodermal dysplasia-cleft patients, by enhancing current surgical techniques, there is promising potential for improved patient outcomes, achieving normognathic facial appearance with implant supported rehabilitation.

Segmental Maxillary Distraction Osteogenesis With a Hybrid-Type Distractor in the Management of Wide Alveolar Cleft

OBJECTIVE

To investigate segmental maxillary distraction osteogenesis (DO) with hybrid-type distractor in the management of wide alveolar cleft.

PATIENTS AND METHODS

Six patients underwent segmental DO with a hybrid-type distractor. After the success of DO and 3-month consolidation period, removal of the distractor was accompanied by alveolar bone graft with iliac bone. Panoramic radiograph and computed tomography scanning were taken preoperatively (T0) and the day after distractor removal (T1). The crest distance between the long axis of cleft nearby teeth was measured.

RESULT

All patients completed the DO period, and the succeeding alveolar bone graft healing was uneventful. The mean cleft distance decrease was 12.05 mm (range: 10.1-13.5 mm). As for the mobility degree record of abutment tooth in the transport segment recorded, 6 patients were grading I° at T0, while 5 patients were grading I° and 1 patient was grading II° at T1.

CONCLUSION

Segmental maxillary DO with the hybrid-type distractor is successful to reduce the cleft width in these cases, and it is promising in the treatment of wide dental alveolar cleft, especially for the adult patient.

Two-stage reconstruction of the severely deficient alveolar ridge: bone graft followed by alveolar distraction osteogenesis

Distraction osteogenesis for the augmentation of severe alveolar bone deficiency has gained popularity during the past two decades. In cases where the vertical bone height is not sufficient to create a stable transport segment, performing alveolar distraction osteogenesis (ADO) is not possible. In these severe cases, a two-stage treatment protocol is suggested: onlay bone grafting followed by ADO. An iliac crest onlay bone graft followed by ADO was performed in 13 patients: seven in the mandible and six in the maxilla. Following ADO, endosseous implants and prosthetic restorations were placed. In all cases, the onlay bone graft resulted in inadequate height for implant placement, but allowed ADO to be performed. ADO was performed to a mean total vertical augmentation of 13.7mm. Fifty-two endosseous implants were placed. During a mean follow-up of 4.85 years, two implants failed, both during the first 6 months; the survival rate was 96.15%. In severe cases lacking the required bone for ADO, using an onlay bone graft as a first stage treatment increases the bone height thus allowing ADO to be performed. This article describes a safe and stable two-stage treatment modality for severely atrophic cases, resulting in sufficient bone for implant placement and correction of the inter-maxillary vertical relationship.

Controlling the vector of distraction osteogenesis in the management of obstructive sleep apnea

Background:

Obstructive sleep apnea (OSA) in individuals with craniofacial anomalies can compromise airway and is a serious life-threatening condition. In many cases, tracheostomy is carried out as the treatment of choice. Distraction osteogenesis of the mandible as a treatment modality for OSA is very useful and may spare the need for tracheostomy or allow decannulation, yet controlling the vector of distraction is still a major challenge. We present a method for controlling the vector of distraction.

Materials and Methods:

Eight patients with severe respiratory distress secondary to a micrognathic mandible were treated by mandibular distraction osteogenesis using either external or internal devices. Temporary anchorage devices (TADs) and orthodontic elastics were used to control the vector of distraction. Cephalometric X-rays, computed tomography, and polysomnographic sleep studies were used to analyze the results.

Results:

A mean distraction of 22 mm using the internal devices and a mean of 30 mm using the external devices were achieved. Increase in the pharyngeal airway and hyoid bone advancement was also observed. Anterior-posterior advancement of the mandible was noted with no clockwise rotation. Most importantly, clinical improvement in symptoms of OSA, respiratory distress, and feeding was noted.

Conclusions:

We describe a method for controlling the vector of distraction used as a treatment for OSA. In these cases, TADs were used as an anchorage unit to control the vector of distraction. Our results show excellent clinical and radiographical results. TADs are a simple and nonexpensive method to control the vector of distraction.

Immediate Reconstruction of Large Full-Thickness Segmental Anterior Maxillary Defect with Bone Transport

Maxillary segmental defects are a reconstructive challenge particularly when the anterior arch is involved. Missing bone, mucosa, and teeth should be replaced; fistulae closure should be guaranteed by bone and mucosa continuity; stable functional occlusion should be achieved; and facial aesthetics restored. These defects resulting from tumor excisions, if left untreated, will cause additional problems related to interposed scar and collapse of lip and nose. Immediate reconstruction should avoid these problems and should be considered when safe tumor-free margins are obtained. This study describes the treatment of such a defect resulting from a myxoma excision, with trifocal distraction requiring only one additional surgery. Internal distractors were fixed bilaterally for transport of two segmental discs created by inverted L osteotomies at the same surgical time of tumor excision. A second surgery was performed after central contact between transport discs was achieved, for device removal and creation of a dynamic system to regenerate molding and compression-focus development. This was accomplished by internal fixation of one side and central fixation of a full-open distractor to act as compression device when reversely activated. Central perfect adaptation between transported segments and good-quality attached mucosa lining the alveolar crest were determinant to obtain a stable functional and aesthetic result.

Analysis of implant-failure predictors in the posterior maxilla: a retrospective study of 1395 implants

The aim of this study was to analyze predictors for dental implant failure in the posterior maxilla. A database was created to include patients being treated with dental implants posterior to the maxillary cuspids. Independent variables thought to be predictive of potential implant failure included (1) sinus elevation, (2) implant length, (3) implant diameter, (4) indication, (5) implant region, (6) timepoint of implant placement, (7) one-vs. two-stage augmentation, and (8) healing mode. Cox regression analysis was used to evaluate the influence of predictors 1-3 on implant failure as dependent variable. The predictors 4-9 were analyzed strictly descriptively. The final database included 592 patients with 1395 implants. The overall 1- and 5-year implant survival rates were 94.8% and 88.6%, respectively. The survival rates for sinus elevation vs. placement into native bone were 94.4% and 95.4%, respectively (p = 0.33). The survival rates for the short (<10 mm), the middle (10-13 mm) and the long implants (>13 mm) were 100%, 89% and 76.8%, respectively (middle-vs. long implants p = 0.62). The implant survival rates for the small- (<3.6 mm), the middle- (3.6-4.5 mm) and the wide diameter implants (>4.5 mm) were 92.5%, 87.9% and 89.6%, respectively (p = 0.0425). None of the parameters evaluated were identified as predictor of implant failure in the posterior maxilla.

Isolated keratinized gingiva incision in alveolar cleft bone grafts improves qualitative outcomes: a single surgeon's 23 year experience

BACKGROUND

Few publications have described the flap design of the secondary cleft alveoloplasty. In this article we describe a modified technique of the classical flap design with the purpose of minimizing injury to the dental papillae and periodontium of the involved dentition. We report our long-term experience, specifically with regards to oronasal fistulae recurrence, wound healing and graft exposure and loss.

METHODS

All the patients were operated on using the same technique by a single surgeon. A total of 148 clefts have been operated with this approach, involving 117 patients with complete cleft lip and palate with a follow-up between 12 and 240 months.

RESULTS

The most important finding in this study is the excellent wound healing observed in almost all patients. Only three patients (2%) suffered a dehiscence with oronasal fistulae recurrence and bone loss. Another patient lost the graft without fistula recurrence. Minor dehiscence with partial bone loss occurred in 4 patients (2.7%). These patients did not need surgical closure and only superficial exposed bone particles were lost without compromising the clinical outcome.

CONCLUSIONS

Our modification presents a flap design that is easy to elevate and mobilize, without disturbing the buccal sulcus or the gingival inter-dental papillae.

Interdisciplinary treatment of a patient with bilateral cleft lip and palate and congenitally missing and transposed teeth

The comprehensive treatment of a patient with cleft lip and palate requires an interdisciplinary approach for functional and esthetic outcomes. A 20-year-old woman with bilateral cleft lip and palate had a chief complaint of unesthetic appearance of her teeth and the presence of oronasal fistulae. Her clinical and radiographic evaluation showed a dolichofacial growth pattern, a Class II skeletal relationship with retroclined maxillary central incisors, 5 mm of negative overjet, maxillary constriction, maxillary and mandibular crowding, congenitally missing maxillary right incisors and left lateral incisor, and a transposed maxillary left canine. Her treatment plan included the extraction of 3 premolars, maxillary expansion, segmental maxillary osteotomy, repair of the oronasal fistulae, rhinoplasty, periodontal surgery, and prosthodontic rehabilitation. To obtain a better occlusion and reduce the dimensions of the fistulae, orthognathic surgery comprising linear and rotational movements of the maxillary segments (premaxilla, right and left maxillary alveolar segments) in all 3 axes was planned by performing 3-dimensional virtual surgery on 3-dimensional computerized tomography. At the end of the interdisciplinary treatment, a functional occlusion, a harmonious profile, and patient satisfaction were achieved. Posttreatment records after 1 year showed stable results.

Evaluation of bone regenerative capacity following distraction osteogenesis of goat mandibles using two different bone cutting techniques

PURPOSE

To compare the regenerative capacity of goat mandibles following sagittal split osteotomy and distraction osteogenesis with a vertical body osteotomy.

ANIMALS AND METHODS

Bilateral vertical and sagittal body osteotomy was performed on the left and right sides of the mandibles in 18 goats. The distraction period lasted for 10 days at 1 mm/day. Animals were sacrificed at 0, 10, and 35 days post-distraction. Bone mineral density (BMD) and bone volume (BV) were analysed by microcomputed tomography (MCT). Types of bone and cells present in the regenerated defect sites were analysed histologically.

RESULTS

At 0, 10, and 35 days, BMD was 0.358 ± 0.012, 0.410 ± 0.012, and 1.070 ± 0.019, respectively, for vertical osteotomy and 0.420 ± 0.013, 0.421 ± 0.009 and 1.182 ± 0.030, respectively, for sagittal osteotomy. BV was 973.310 ± 5.048, 1234.589 ± 4.159, and 2121.867 ± 6.519, respectively, for vertical osteotomy and 995.967 ± 2.781, 1755.938 ± 4.379, and 2618.441 ± 21.429, respectively, for sagittal osteotomy at these three time points. BMD and BV differed significantly at all three times. Histological analysis shows that sagittal splitting was characterized by more robust lamellar bone formation bridging the distraction gap than vertical body osteotomy.

CONCLUSION

Both MCT and histological analyses showed that distraction using the sagittal osteotomy technique resulted in significantly higher BV and BMD than using vertical body osteotomy.

Modified VIP-CT flap in late maxillary alveolar cleft surgery

OBJECTIVE

This article describes a new application for the modified vascularized interpositional periosteal-connective tissue flap (modified VIP-CT flap) to solve problematic cases of late maxillary alveolar cleft bone grafting.

METHODS

This study analysed the ability of the VIP-CT flap to provide coverage of bone grafts in maxillary alveolar cleft surgery. Donor site morbidity was also evaluated.

RESULTS

Thirteen patients were operated on using this technique, seven patients were female, the age range was between 12 and 25 years, and all of them were missing at least one permanent anterior tooth adjacent to the cleft. Two patients had bilateral alveolar clefts. In most of the operated patients one VIP-CT flap was used, but in two patients (cases 3 and 4) bilateral VIP-CT flaps were used for treatment of wide alveolar clefts. In case 3 both of the flaps were used for closure of the oral side and in case 4 one flap was used for nasal closure and another for oral side coverage. Two patients had alveolar cleft only with normal palatal anatomy, and the remaining patients had previously operated cleft palates (11 patients).

CONCLUSION

VIP-CT flaps can readily be used in adult patients with cleft lip (alveolar only) and in many operated unilateral and bilateral complete cleft lip and palate patients successfully.