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S Kreiborg

Publications and source records attributed to S Kreiborg.

At least 37 records · Page 2Linked to original sources
PubMed1999

Oral manifestations of Schimmelpenning syndrome: case report and review of literature.

Schimmelpenning syndrome (SS) is characterised by specific skin manifestations, skeletal defects, and central nervous system abnormalities. Here, the SS is briefly reviewed, and the oral and dental manifestations are described in a patient whose medical findings were previously published and included severe hypophosphatemic rickets. Significant oral and dental features included papillomatous lesions of the gingiva, hemihyperplasia (hemihypertrophy) of the tongue, bone cysts, aplasia of teeth, enlarged pulp chambers, hypoplastic or absent enamel, and an odontodysplasia-like permanent tooth.

Adolescent↗
PubMed1998

Perspectives on craniofacial syndromes.

This article reviews syndrome classification; types of anomalies and their interrelations; syndrome delineation; birth prevalence; nomenclature; molecular delineation; and phenotype/genotype correlations.

Craniofacial Abnormalities↗
PubMed1998

Is craniofacial morphology in Apert and Crouzon syndromes the same?

This article reviews previous research on the craniofacial development in Apert and Crouzon syndromes and adds new roentgencephalometric information. It is concluded that craniofacial development in the two syndromes is not the same. Marked differences were found in the calvaria, cranial base, orbit, maxilla, zygoma, incisal occlusion, and soft tissue profile. In general, abnormal craniofacial morphology was more severe in Apert syndrome than in Crouzon syndrome.

Acrocephalosyndactylia↗
PubMed1998

Adhesive bonding of fragmented anterior teeth.

This in vitro study investigated the fracture strengths of fractured incisors after reattachment to the remaining tooth structure, using either Gluma dentin-bonding agent together with 1 of 13 different experimental resins or 1 of the following dentin-bonding agents: Gluma+ (experimental modification of Gluma), Panavia21, ScotchBond1 (SingleBond), All-Bond2, Dentastic, SuperBond, Prime&Bond 2.1. No significant differences were found in the experiments with various experimental resins. The fracture strength of teeth rebonded with Gluma, All-Bond2, Dentastic, SuperBond or Prime&Bond 2.1 showed mean fracture strengths in the range of 8.7-11.2 MPa, which were significantly different in all cases from that of intact teeth (16.3 MPa). Teeth bonded with Gluma+, Panavia21 or ScotchBond1 (SingleBond) showed mean fracture strengths of 15.5, 14.6, and 14.2 MPa, respectively. These fracture strengths were not significantly different from that of intact teeth.

Animals↗
PubMed1998

Adhesive bonding of fractured anterior teeth: effect of wet technique and rewetting agent.

PURPOSE: To compare the fracture strength of intact teeth with that of fractured crowns bonded with adhesive and a resin material on either wet or dry dentin, or dried dentin rewetted with a rewetting agent for various periods of time. MATERIALS AND METHODS: Sheep central incisors were divided into seven groups, each of 10 teeth. Group 1: Intact teeth tested for fracture strength in an Instron testing machine and used as controls. Groups 2-7 were sectioned in a vice equipped with sharp blades, 2.5 mm away from and parallel to the incisal edge. The two fracture surfaces were etched with 37% phosphoric acid for 15 s and rinsed with water for 5-6 s. Group 2: The surfaces were air-dried for 2 s. Group 3: As for Group 2 but the surfaces were rewetted with Aqua-Prep for 2 s and immediately air-blasted to remove excess. Group 4: As for Group 3, but the rewetting agent was applied for 10 s before air-blasting. Group 5: As for Group 4, but the rewetting agent was applied for 20 s. Group 6: As for Group 4, but the rewetting agent was applied for 30 s. Group 7: As for Group 2, but the surfaces were left moist after etching and rinsing by gently shaking the specimens twice. The fracture surfaces of Groups 2-7 were rebonded with All-Bond 2 adhesive system and Aeliteflo composite. After 48 hrs the restored teeth were debonded in the Instron testing machine. Fracture strengths were calculated and compared with the fracture strength of intact teeth (control group). RESULTS: Newman-Keuls' multiple range test revealed that there was a statistically significant difference between the control mean and the means of Groups 2 and 3. All other means were not significantly different. Drying of the dentin surface decreased the bonding strength, and rewetting of the dried dentin for 2 s was not sufficient to rewet the collapsed collagen fibers, as indicated by a decrease of fracture strength.

Acid Etching, Dental↗
PubMed1996

Suture formation, premature sutural fusion, and suture default zones in Apert syndrome.

On the basis of our studies, we postulate that suture formation in Apert syndrome is related to the relative maturity of abutting calvarial bones. The fused coronal suture, a consistent manifestation at birth, develops first because the ossification centers of the frontal and parietal bones are in intimate contact early during intrauterine life. Calvarial immaturity and the megalencephalic brain characteristic of the Apert syndrome appear to work in concert to produce a widely patent midline calvarial defect extending from the glabella to the posterior fontanelle. Because sagittal growth in the coronal sutures cannot take place, the megalencephalic brain grows upward and laterally, and bulges forward through the midline defect. The defect fills in by coalescence of bony islands without proper suture formation because the gap to be bridged is so great that the time window for developing sutural interdigitations may have closed. Other sutures, such as the lambdoid, squamosal, and sphenotemporal, develop with normal interdigitations because abutting bone margins are in close enough proximity to permit suture formation.

Acrocephalosyndactylia↗
PubMed1996

First-trimester prenatal diagnosis of Crouzon syndrome.

Crouzon syndrome, one of the best known of many craniofacial syndromes, is an autosomal dominant disorder characterized by craniosynostosis, prominent eyes, and midfacial hypoplasia due to abnormal development and premature fusion of the skull. Recently mutations in the fibroblast growth factor receptor 2 gene (FGFR2) were found to cause Crouzon. We have identified the recurrent mutation C342Y in two unrelated patients with Crouzon syndrome. One patient (A) belongs to a family in which Crouzon could be followed in three generations, while the other patient (B) represents a sporadic case. The identification of the disease-causing mutation allowed first-trimester prenatal diagnosis as requested by both patients in their subsequent pregnancies. A chorionic villus biopsy was performed in the 11th gestational week of patient A's pregnancy. DNA isolated from the biopsy revealed a fetus heterozygous for the C342Y mutation, i.e., having Crouzon syndrome. The pregnancy was terminated and the molecular diagnosis was confirmed later by analysis of fetal and placental tissue. Patient B had a missed abortion before the scheduled chorionic villus biopsy was performed. Mutation analysis of the aborted fetal tissue did not show the C342Y mutation.

Base Sequence↗
PubMed1996

A clinical study of the craniofacial features in Apert syndrome.

A clinical study of the craniofacial features in Apert syndrome is based on our experience with 136 cases. Characteristics included hyperacrobrachycephaly, steep wide forehead, flat occiput, common craniofacial asymmetry, ocular hypertelorism and proptosis, downslanting palpebral fissures, divergent upgaze and esotropic downgaze, a tendency towards large ears, and marked depression of the nasal bridge. The nose is short and wide with a bulbous tip, and the anterior facial height is reduced. Common features during infancy included horizontal grooves above the supraorbital ridges that disappear with age, a break in the continuity of the eyebrows, and a trapezoidal-shaped mouth at rest. Radiographic aspects of Apert syndrome were also assessed. Tables are provided which compare the craniofacial features of Apert and Crouzon syndromes.

Acrocephalosyndactylia↗
PubMed1996

The role of bone centers in the pathogenesis of craniosynostosis: an embryologic approach using CT measurements in isolated craniosynostosis and Apert and Crouzon syndromes.

This paper describes the role of the displacement of bone centers, i.e., the tubers, in the pathogenesis of craniosynostosis. This displacement was studied in 54 patients with isolated or syndromic craniosynostosis in the form of CT scans as well as in two dry neonate skulls with Apert syndrome. For comparison, 49 fetal and 8 normal infant dry skulls were studied. Our investigation was restricted to the coronal and metopic sutures. The results showed a significantly more occipital localization of the frontal bone center and a more frontal localization of the parietal bone center at the side of a synostotic coronal suture in the isolated form as well as in Apert syndrome. In contrast, this was not the case in Crouzon syndrome, thus showing that these two syndromes have a different pathogenesis. For trigonocephaly, a more anteromedial localization of the frontal bone centers was found.

Acrocephalosyndactylia↗
PubMed1995

Hands and feet in the Apert syndrome.

We studied 44 pairs of hands and 37 pairs of feet in Apert syndrome, utilizing clinical, dermatoglyphic, and radiographic methods. We also studied histologic sections of the hand from a 31-week stillborn fetus. Topic headings discussed include: clinical classification of syndactyly; correlations between types of hands and feet in the same patient; dermatoglyphics; anatomy of the hand; radiologic assessment; comparison with other studies; histologic assessment of the hand; acrocephalosyndactyly vs. acrocephalopolysyndactyly: a pseudodistinction; and some generalizations.

Acrocephalosyndactylia↗
PubMed1993

Growth pattern in the Apert syndrome.

In this paper, we demonstrate that a discernible and unique growth pattern characterizes the Apert syndrome. The keys to understanding Apert newborn measurement values are brain size and cranial configuration. Both true megalencephaly and coronal synostosis are present at birth. Thus, the head is unusually heavy and the cranium is disproportionately high. Mean newborn length and weight are above the normal 50th centile. Of our newborn patients, 16% exceeded 4,000 g in weight. Preterm infants were appropriate or slightly large for gestational age. A biphasic linear growth pattern was found. In childhood, deceleration of linear growth occurs so that most values fall between the 5th and 50th centiles. From adolescence to adulthood, deceleration becomes more pronounced. This 2-step linear growth deceleration results in large measure from rhizomelic shortness of the lower limbs. Puberty takes place within the normal time frame. Although a disproportionate amount of the megalencephaly accounts for the dramatic increase in head height, the widely patent midline calvarial defect, allowing the brain to expand anteriorly into the metopic area, and some increase in the head breadth permit the mean head circumference at birth to normalize slightly above the 50th centile. During the growth period, the head circumference was studied in surgically unoperated Apert patients from the 1960s and earlier. The natural history of the growing cranium consists of gradual deceleration in head circumference from slightly above the 50th centile at birth to within or at -2 SD later on.

Acrocephalosyndactylia↗
PubMed1993

Skeletal abnormalities in the Apert syndrome.

This paper reports on skeletal abnormalities in 38 patients with Apert syndrome. Analysis includes alterations in the shoulders, humeri, elbows, hips, knees, rib cage, and spine (except the cervical spine). Some patients had subacromial dimples and elbow dimples during infancy. Mobility at the glenohumeral joint was limited. Progressive limitation in abduction, forward flexion, and external rotation with growth was virtually a constant finding. The acromioclavicular joint was prominent and sometimes had an angular, pointed appearance clinically. This was often associated with atrophic musculature and winging of the scapulae. Limited elbow mobility was common and usually mild in degree. Decreased elbow extension was most often found with decreased flexion, pronation, and supination occurring less frequently. Limited elbow mobility did not change significantly with growth in contrast to the increasing severity observed in the shoulder joint. Short humeri were a constant finding beyond infancy and genua valga of mild degree were present in many cases. Radiographic examination strongly suggests that the Apert syndrome is characterized by a multiple epiphyseal dysplasia. We found delay in appearance of postnatal ossification centers, particularly in the humeral head, greater tuberosity, capitulum, and radial head. Subsequently, these bones became abnormal in shape. Glenoid dysplasia was observed consistently. The neck of the scapula was very short or absent and the inferior margin of the glenoid cavity was poorly demarcated from the infraglenoid tubercle. The humeral head became oblong in shape with relative prominence of the greater tuberosity which compromised abduction. In the elbow, the capitulum was often small and the radial head was flat in many instances.(ABSTRACT TRUNCATED AT 250 WORDS)

Acrocephalosyndactylia↗
PubMed1993

Cranial base and face in mandibulofacial dysostosis.

Using longitudinal roentgencephalometry, we studied craniofacial growth in two children with mandibulofacial dysostosis. In one child, data were supplemented by three-dimensional reconstructions of CT scans and stereolithographic models of the craniofacial skeleton. Progressive basilar kyphosis was found in both children, the hypothesized caused being bending of the cranial base at the level of the sphenofrontal suture. Such bending acting in concert with abnormal growth of the mandible led to impairment of the airway. We advocate careful monitoring of craniofacial growth and respiratory function in mandibulofacial dysostosis from birth through adolescence.

Adolescent↗
PubMed1993

Visceral anomalies in the Apert syndrome.

We report on visceral anomalies found in 136 patients with Apert syndrome. Autopsies were only performed on 12 of these cases. Thus, the percentage of anomalies found in our patients should be considered a minimum estimate because of the possibility of clinically silent visceral anomalies, minor internal anomalies, and anatomic variations. Cardiovascular and genitourinary anomalies were found most commonly, occurring in 10% and 9.6%, respectively. As expected, complex and multiple cardiac anomalies were frequently associated with early death. Among genitourinary anomalies, hydronephrosis (3%) and cryptorchidism (4.5%, n = 66 males) occurred most commonly. In contrast, anomalies of the respiratory system (1.5%) and gastrointestinal anomalies (1.5%) occurred with lower frequency. The finding of a solid cartilaginous trachea is particularly important because no case was diagnosed during life but rather, only at autopsy. Because cardiovascular and genitourinary anomalies occur with significant frequency, they should be considered in the workup of all Apert newborn infants. We also recommend MRI study of the trachea in any infant with signs and symptoms of lower respiratory compromise.

Acrocephalosyndactylia↗
PubMed1993

An updated pediatric perspective on the Apert syndrome.

This review of the Apert syndrome, based on our research experience with 136 cases, provides a clinically relevant pediatric perspective. The brain is megalencephalic, resulting in a disproportionately high cranium and a mean birth length and weight above the 50th percentile. The growth pattern in childhood consists of a slowing of linear growth so that most values fall between the 5th and 50th percentiles. From adolescence to adulthood, slowing becomes more pronounced. Central nervous system abnormalities may occur in some cases, including malformations of the corpus callosum and limbic structures, gyral abnormalities, hypoplastic white matter, and heterotopic gray matter. Distortion ventriculomegaly is found because of the large brain in a misshapen skull. Progressive hydrocephalus is uncommon. Intelligence in patients with the Apert syndrome varies from normality to mental deficiency. Early release of the coronal suture and advancement and reshaping of the frontal bone reduce further dysmorphic and unwanted growth changes in the skull, but probably do not affect mentation. Associated cardiovascular and genitourinary anomalies occur in 10% and 9.6% of cases, respectively. Other important findings reviewed include upper- and lower-airway compromise, calvarial development, cervical vertebral anomalies, limb defects, ocular and otologic manifestations, and dermatologic characteristics.

Acrocephalosyndactylia↗
PubMed1993

Comparative three-dimensional analysis of CT-scans of the calvaria and cranial base in Apert and Crouzon syndromes.

The purpose of this study is to describe and analyze Apert and Crouzon skulls from three-dimensional (3-D) reconstructions of CT-scans. 12 Apert patients and 19 with Crouzon syndrome were included in the study. The age range was 0 to 23 years. All CT-scannings were carried out according to the same protocol with a slice thickness of 2 or 4 mm and 3-D reconstructions of the craniofacial region included midsagittal and horizontal cuts. A number of qualitative characteristics of the calvaria and cranial base were recorded and the cranial base angle was measured on the 3-D models. Our results showed that Apert and Crouzon syndromes are very different in cranial development and their dysmorphology is highly age dependent. We suggest that cartilage abnormalities, especially in the anterior cranial base, play a primary role in cranial development in the Apert syndrome from very early intrauterine life. Several cranial anomalies observed postnatally, however, are caused by the resultant dysmorphic and compensatory growth and are probably compounded by early cranial deformation. The primary abnormality in Crouzon syndrome appears to be premature fusion of sutures and synchondroses. Based on the findings at birth and early infancy it would seem that such fusions occur relatively late in fetal life. The adult cranial form in Crouzon's patients is explainable by resultant dysmorphic and compensatory growth changes. Very early release of the coronal suture areas with advancement of the frontal bone is advocated in both syndromes but for somewhat different reasons.(ABSTRACT TRUNCATED AT 250 WORDS)

Acrocephalosyndactylia↗