ISSN:1049-2275    

出版商:OVID    

年代:1998

数据来源: OVID

ISSN:1049-2275    

出版商:OVID    

年代:1998

数据来源: OVID

ISSN:1049-2275    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

A substantial interest exists in developing substitute materials and human recombinant boneinducing factors to enhance bone regeneration both in the craniofacial complex and in other parts of the skeleton. A persistent problem has been to find an animal model that allows for the comparison of different osteopromotive materials. The purpose of this investigation was 1) to determine whether a 5-mm calvarial defect in adult rats fulfilled the requirements of a critical-size bone defect and 2) to discuss the use of this animal model in assessing bone repair in the craniofacial region. Bilateral full-thickness calvarial defects were trephined in the calvarial bone of 56 5− to 6-month-old Wistar rats. Except for minor amounts of bone formation limited to the margins of the defect, none of the defects revealed any signs of spontaneous bone regeneration 6 and 12 months after surgery. The full-thickness 5-mm calvarial defects thus fulfill the criteria for a critical-size bone defect. This animal model allows for an experiment with a paired design, it avoids inclusion of the sagittal suture in the osseous defect, and it thereby minimizes morbidity by reducing the risk of damaging the midsagittal sinus. An adequate experimental model has been developed to evaluate the efficiency of osteopromotive materials in the healing of bone defects in the craniomaxillofacial region.

ISSN:1049-2275    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

The use of nonmetallic rigid fixation (plate and screws) composed of resorbable polymers (poly L-lactic acid and polyglycolic acid) for the repair of isolated maxillary (LeFort I) fractures was studied in 11 patients. Provided good bone (noncommi-nuted) was available for fixation placement, no differences were observed in intraoperative maxillary stability or long-term postoperative results.

ISSN:1049-2275    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Distraction osteogenesis has been shown to be an effective method of lengthening and augmenting endochondral bone. It has also been applied effectively in the reconstruction of the membranous bones of the craniofacial skeleton. With the accumulation of clinical experience in mandibular distraction, the differences between endochondral and membranous bone distraction have become apparent, especially in the limitations of uniplanar distraction for the three-dimensional reconstruction of the deficient mandible. Distraction of the mandible in a single plane cannot satisfy fully the functional and structural requirements of the patient with malocclusion as well as deficiency of the skeletal and soft tissue. This study reports the development and clinical use of a multiplanar mandibular distraction device with the ability to achieve linear distraction (Z-plane or sagittal), angular distraction (Y-plane or vertical), and transverse distraction (X-plane or coronal). The device contains two independent gear arrangements attached to two arms that extend from the central unit. Therefore, the trajectory of the regenerated bone may be changed during the distraction process. The device also allows manipulation of the various planes of movement independent of each other. Furthermore, the rotational points for the multiplanar distraction devices are located at a single point; therefore only a single osteotomy and two pin sites are required. The multiplanar distraction device allows the surgeon to customize and contour the dimensions of the distraction process by controlling the trajectory of the translation of the regenerated bone.

ISSN:1049-2275    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

The development of velopharyngeal incompetence and increased hypernasality after maxillary advancement has been described previously by several authors. If speech and velopharyngeal function deteriorate after maxillary advancement, pharyngoplasty is frequently the treatment procedure of choice because of the natural cause of the deficit. Of 91 cleft lip and palate patients who have undergone maxillary advancement at the Australian Cranio-Facial Unit, 23 patients received a pharyn-goplasty after surgery. Thirteen of these patients who had pre- and postoperative speech evaluations were included in this study. Of the 13 patients, six patients received a superiorly based pharyngeal flap, two patients underwent an orticocheal pharyngoplasty, and five patients received either a revision or augmentation of the previous flap based on results of preoperative examinations. Serial nasendoscopic evaluations were available for 11 of these 13 patients, and they demonstrated that velopharyngeal function improved after pharyngoplasty in six patients and was unchanged in five patients. Of the 13 patients, 10 improved and three patients were unchanged on an intelligibility rating. Nine of the 13 patients demonstrated decreased hypernasality and four patients were unchanged. Hyponasality decreased in two patients increased in one patient, and was unchanged in one patient. Because the results obtained are considered acceptable, the authors conclude that pharyngoplasty can be used effectively to treat velopharyngeal dysfunction subsequent to Le Fort I maxillary advancement.

ISSN:1049-2275    

出版商:OVID    

年代:1998

数据来源: OVID

ISSN:1049-2275    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

For the treatment of mild crossbite with increased bigonial distance, the authors performed a vertical symphyseal osteotomy on six patients in the last 3 years. Three of these patients had cleft lip deformities and the others had operations for orthodontic or aesthetic reasons. After exposing the mandible through the buccal mucosal incision, both premolars were extracted with or without conventional segmental osteotomy. The two vertical symphyseal osteotomies were performed with approximately 1 cm between them, and the central part of the mandibular bone was discarded. The bilateral segments of the mandibular body were fixed in the midline using titanium miniplates. Satisfactory results were obtained with a reduction in the size of the mandibular arch, which produced better three-dimensional proportions in the bimaxillary area. No patients had temporomandibular joint problems, however postoperative orthodontics were essential for this type of operation.

ISSN:1049-2275    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

Craniofacial procedures commonly use scalp incisions to optimize surgical access and aesthetic results. Although the use of traditional electrocau-tery instruments on hair-bearing tissue has been limited secondary to the width of resulting alopecia, needle-tipped electrocautery devices with decreased energy transmission have been developed. This study investigates the cosmetic effect of such instruments on scalp incisions. Twelve children undergoing craniosynostotic correction via bicoronal incisions were included. One side of the incision was completed with the cold scalpel whereas the contralateral portion was effected using the Colorado MicroDissection Needle (Colorado Biomedical Inc., Evergreen, CO, U.S.A.) according to optimal usage instructions. At the conclusion of the study period, precise measurements of the resultant width of alopecia were obtained from the parietal and temporal regions bilaterally, and were analyzed statistically. Also, parents completed a questionnaire concerning subjective observations of the surgical incision and its healing. The portions of the incision completed with the Colorado MicroDissection Needle demonstrated a wider area of peri-incisional alopecia (5.8 \pm 1.8 mm) than that produced by the cold scalpel (3.5 \pm 0.87 mm). Not only was this increased width significant statistically (P< 0.05), in addition the disparity was noted by the majority of parents (10 of 12) either on the patient questionnaire or with nonsuggestive verbal questioning. The benefit of the hemostatic incisional technique of electrocautery with even needle-tipped instruments must be weighed carefully against its cosmetic consequences.

ISSN:1049-2275    

出版商:OVID    

年代:1998

数据来源: OVID