Transpalatal distraction osteogenesis prior to alveolar bone grafting in cleft lip and palate patients

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.

Development and characterization of elastic nanocomposites for craniofacial contraction osteogenesis

Development of resorbable elastic composites as an alternative means to apply contractive forces for manipulating craniofacial bones is described herein. Composites made from the biodegradable elastomer, poly (1,8-octanediol co-citric acid) (POC), and hydroxyapatite (nHA) with a 200 nm diameter (0-20% loadings) were created to develop a material capable of applying continuous contractive forces. The composites were evaluated for variation in their mechanical properties, rate of degradation, and interaction of the hydroxyapatite nanoparticles with the polymer chains. First, an ex vivo porcine model of cleft palate was used to determine the rate of cleft closure with applied force. The closure rate was found to be 0.505 mm N(-1) . From this approximation, the ideal maximum load was calculated to be 19.82 N, and the elastic modulus calculated to be 1.98 MPa. The addition of nHA strengthens POC, but also reduces the degradation time by 45%, for 3% nHA loading, compared to POC without nHA. X-ray diffraction data indicates that the addition of nHA to amorphous POC results in the formation of a semicrystalline phase of the POC adjacent to the nHA crystals. Based on the data, we conclude that amongst the 0-20% nHA loadings, a 3% loading of nHA in POC may be an ideal material (1.21 MPa elastic modulus and 13.17 N maximum load) to induce contraction forces capable of facilitating osteogenesis and craniofacial bone repair.

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.

Treatment of alveolar cleft with distraction osteogenesis using anchorage with a tooth-microimplant joint in a dog model

Our aim was to investigate the efficacy of correction of an alveolar cleft with distraction osteogenesis using anchorage with a tooth-microimplant joint in a canine model, which was established in 12 adult mongrel dogs that were subsequently randomised into two groups (n=6 in each). The first group comprised dogs that had osteogenesis using anchorage with a tooth (tooth group), while in the second, anchorage with tooth-microimplant joint (microimplant group) was used. All animals were killed one month after completion of distraction. Samples were collected for gross observation and histological examination. There was a significant difference in the degree of movement of the anchorage teeth in the transport discs between the 2 groups (p<0.01). There was less prominent inclination and shift of the natural teeth in the transport disc and less bony resorption around the root in the microimplant group than in the tooth group. These changes were less remarkable in the microimplant group. Treatment of alveolar cleft by distraction osteogenesis using anchorage with a tooth-microimplant joint is practical, and yields better results.