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S A Schendel

Publications and source records attributed to S A Schendel.

18 recordsLinked to original sources
PubMed1992

An analysis of Le Fort I maxillary advancement in cleft lip and palate patients.

We present a series of 24 consecutive cleft lip and palate patients aged 16 to 46 years (mean age 27 years) who underwent Le Fort I maxillary advancement by the senior author over the past 8 years. Two groups, one of 12 patients with wire fixation and one of 12 patients with miniplate fixation, were evaluated. Each group had 10 unilateral and 2 bilateral clefts. All patients were grafted with autogenous bone (8 cranial, 14 iliac, and 2 mandibular). Horizontal advancement was 3 mm to 2 cm (with a mean of 7.8 mm). Vertical movement ranged from a shortening of 5 mm to a lengthening of 1.3 cm (mean 2.3 mm of lengthening). The amount and timing of relapse were compared in both the horizontal and vertical dimensions. The plated group was more stable in both the horizontal and vertical dimensions (p < 0.05). No significant skeletal relapses occurred after the first year. Statistically significant dental relapse occurred only in the wired group. Three patients developed transverse collapse of the small maxillary cleft segment, and four developed incisor angulation to compensate for maxillary skeletal relapse. The presence of a pharyngeal flap at the time of advancement appeared to increase relapse in both horizontal and vertical dimensions (p < 0.03), but there were too few patients (7 of 24) with pharyngeal flaps to prove this conclusively. We also concluded that pterygomandibular grafting is not necessary to achieve excellent results using miniplate fixation; autogenous grafting of the anterior maxillary osteotomy alone provides the necessary stability.

Adult↗
PubMed1992

New technique?

Explore the source record for details and available documents.

Humans↗
PubMed1991

Nasal considerations in orthognathic surgery.

The functional correction of dentofacial deformities by orthognathic surgery produces major changes in facial appearance. Facial esthetics must therefore be equally appreciated by the orthodontist and the maxillofacial surgeon. The orthodontist must perform a thorough esthetic facial evaluation along with his usual orthodontic evaluation. The treatment plan must then be based on the esthetic evaluation and knowledge of the facial changes caused by orthodontic treatment and skeletal jaw surgery. Central to facial form is the nose. This article will outline the proper functional and esthetic evaluation of the nose in relation to the face. Nasal and upper lip changes associated with maxillary procedures will also be covered in detail. In light of these two areas, proper treatment planning and sequencing will be discussed.

Adolescent↗
PubMed1991

Pathophysiology of cleft lip muscles following the initial surgical repair.

Muscle biopsy specimens taken from the upper lip and perialar area during the time of secondary lip revision and studied by histochemical techniques demonstrate persistent connective-tissue and muscle abnormalities even at a distance from the cleft margins. Some of these changes are consistent with surgically induced denervation-reinnervation of muscle groups in the surgical field. Increased amounts of connective tissue also were found, most likely secondary to the original deformity and the subsequent surgical procedures. Both these changes may be important factors in subsequent abnormal growth and development of the underlying midfacial structures. This study also demonstrated the resolution of previously noted mitochondrial abnormalities found in the primary cleft lip patient.

Adolescent↗
PubMed1990

The iliac crest cartilaginous cap.

Bone and cartilage grafts can be procured from the ilium either separately or as composite chondroosseous grafts when sufficient cartilage is present. The thickness and anatomy of this iliac cartilaginous cap was analyzed in relationship to age in 50 individuals. Histology was that of normal hyaline cartilage. The cartilage alone was more pliable with little memory when compared with auricular or septal cartilage. The cartilage/bone junction was very strong. Cartilage thickness ran from close to 1 cm at age 5 to a diminished zero at age 25.

Bone Transplantation↗
PubMed1989

Pathophysiology of cleft lip muscle.

Although attention has been focused for decades on the correction of cleft lip deformities, our knowledge about the etiology of such deformities has remained presumptive. Sixty-six muscle biopsy specimens from cleft lip infants were obtained at the time of primary closure. Histochemical stains, histographic analysis, and electron microscopy were performed. A nonneurogenic muscle atrophy was seen that varied in severity, with muscle fibers near the cleft being the most atrophic and disorganized. Muscle fibers stained with the modified Gomori trichrome technique also demonstrated "ragged red" fibers typical of a mitochondrial myopathy. Electron microscopy confirmed large accumulations of mitochondria distorting the fibrils. These mitochondria also were increased in size and densely packed with cristae. This study thus demonstrates that the muscles in cleft lip deformities are not normal. Instead, they reflect either myopathy in the facial mesenchymal mitochondrion or at least a delay in maturation. We hypothesize that some of the morphologic deformities associated with cleft lip may cause a failure of mesenchymal reinforcement of the facial processes at a critical time in development.

Cleft Lip↗
PubMed1979

Velopharyngeal anatomy and maxillary advancement.

This study was undertaken to evaluate the radiographic changes in the static velopharyngeal mechanism following total maxillary advancement. Records of 21 patients treated for maxillary retrusion were evaluated. Two groups were present: 13 non-cleft patients and 8 cleft-lip patients. The findings demonstrate an anatomical change in the velopharyngeal mechanism following total maxillary advancement. A similar change occurred in both groups; however, the magnitude is differed. The angle of the soft palate to hard palate increased with surgery (2 degrees per mm. advancement noncleft and 1 degree per mm. cleft). An increase in soft palate length was also seen (.5mm. per mm. advancement non-cleft and .4 mm. per mm. cleft). A pharyngeal need ratio prediction method was established (pharyngeal depth/soft palate length). A ratio of .68--.84 in this study was observed. A ratio greater than one was found to indicate probable velopharyngeal incompetence.

Adolescent↗
PubMed1979

Monophase extraskeletal fixation.

The monophase appliance for extraskeletal fixation of facial fractures is discussed. The technique for its implementation is presented with a discussion of its indications and considerations. Reports of three cases demonstrate clinical applications of this one-step method of extraskeletal fixation.

Adult↗
PubMed1978

Mandibular deficiency syndrome. III. Surgical advancement of the deficient mandible in growing children: treatment results in twelve patients.

The surgical-orthodontic correction of mandibular deficiency in growing children (8 to 16 years of age) can be employed to achieve excellent results. Mandibular advancement by a modified sagittal osteotomy proves to be an acceptable procedure with good skeletal stability. Dentofacial growth following surgery will be harmonious and not adversely affected. Direction of growth varies, with the mandibular plane angle becoming more vertical with an increasing mandibular plane angle.

Adolescent↗
PubMed1978

Revascularization after surgical repositioning of one-tooth dento-osseous segments.

Vascularization, revascularization, and bone healing were studied after two different surgical techniques for surgical repositioning of single-tooth dento-osseous segments in adult mongrel dogs. Microangiographic and histologic studies of both one-stage and two-stage techniques for immediate surgical repositioning of single-tooth dento-osseous segments showed early but transient vascular ischemia, minimal osteonecrosis, and osseous union between most of the osteotomized segments. The attached soft tissue provided an adequate vascular pedicle for immediate repositioning of small dento-osseous segments by interdental and subapical osteotomies. The results of these clinically analogues studies support the clinical use of techniques that maximize the attachment of the gingiva to the mobilized dento-osseous segment.

Alveolar Process↗
PubMed1978

Total maxillary advancement with and without bone grafting.

Computer morphometrics was used to analyze 21 adult patients who underwent total maxillary advancement; ten had bone grafting behind the tuberosity and 11 did not. Each group was subclassified as those with idiopathic maxillary deficiency and those with cleft lip and cleft palate; all patients were treated by the same basic operative technique. The results of the study indicate that those patients who had bone grafts had optimum stability. However, individuals with maxillary deficiency who undergo minimal advancements (less than 0.5 mm) can have overcorrections at surgery and, therefore, do not require bone grafts for good stability.

Adolescent↗
PubMed1977

Biologic basis for modification of the sagittal ramus split operation.

Ten adult rhesus monkeys were used as experimental models to investigate revascularization and bone healing associated with sagittal splitting of the mandibular rami by two different techniques. Microangiographic and histologic studies showed intraosseous ischemia in the margins of the osteotomized segments and areas where the pterygomasseteric sling had been detached. When the mucoperiosteum and pterygomasseteric sling were minimally detached from the proximal segment, intraosseous ischemia and necrosis were significantly reduced. The results support the use of a clinical technique of sagittally splitting the mandibular ramus, which maximizes attachment of the pterygomasseteric sling and mucoperiosteum.

Animals↗
PubMed1976

The long face syndrome: vertical maxillary excess.

There is a clinically recognizable facial morphology, the long face syndrome, which has been incompletely described in the literature. On the basis of the clinical summary in thirty-one adults with this syndrome, an analysis of esthetics, skeletal morphology, and occlusion was undertaken. Herein we report on these findings, which confirm that this basic dentofacial deformity is associated with excessive vertical growth of the maxilla. Dental open and closed bite are two variants of the syndrome. An increased mandibular ramus height is associated with the closed-bite group.

Adolescent↗
PubMed1976

Superior repositioning of the maxilla: stability and soft tissue osseous relations.

The skeletal stability and soft-tissue changes associated with superior repositioning of the maxilla by Le Fort I osteotomy or simultaneous anterior and posterior maxillary osteotomies was studied in thirty patients by means of a computerized craniofacial model. Excellent skeletal stability was demonstrated 14 months postoperatively. Postsurgically, the reduction in lower face height and amount of maxillary incisor exposure resulted in improved facial balance. The use of a computerized osseous and soft-tissue craniofacial model has added a new dimension to evaluation of surgical changes associated with correction of dentofacial and craniofacial deformities.

Adolescent↗