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Purpose: This study investigated histochemically the elastic fibers in human temporomandibular joint (TMJ) discs with varying degrees of tissue degeneration/regeneration to determine whether there are differences that correlate with the histologic findings. Materials and Methods: Ten diseased human TMJ discs and 2 control specimens were studied histochemically by staining with Weigert's resorcin-fuchsin after oxidation with peracetic acid. This technique selectively stains elastic, elaunin, (pre-elastic), and oxytalan fibers. Results: In TMJ discs with an abnormal collagen fiber arrangement, an increased number of oxytalan fibers could be observed, contrary to discs with scar-like tissue transformation in which oxytalan fibers were decreased in number. In discs showing tears and clefts, the oxytalan fibers run perpendicular to the defects, whereas elaunin and elastic fibers were mainly circumferentially arranged. In discs with chondroid metaplasia, elastic, elaunin, and oxytalan fibers were extensively detected. Conclusions: It is hypothesized that the elastic, elauinin, and oxytalan fibers found in severely damaged discs appear to ensure biomechanical compliance by reinforcing regions devoid of collagen bundles and thus function as shock absorbers of stretch and compression. © 2001 American Association of Oral and Maxillofacial Surgeons

OBJECTIVE: To investigate condylar symmetry and condyle fossa relationships in subjects with functional posterior crossbite comparing findings before and after rapid maxillary expansion (RME) treatment through low-dose computed tomography (CT). MATERIALS AND METHODS: Twenty-six patients (14 girls and 12 boys, mean age 9.6 ± 1.4 years) with functional posterior crossbite (FPXB) diagnosis underwent rapid palatal expansion with a Hyrax appliance. Patients' temporomandibular joints (TMJ) underwent multislice CT scans before rapid palatal expansion (T0) and after (T1). Joint spaces were compared with those of a control sample of 13 subjects (7 girls and 5 boys, mean age 11 ± 0.6 years). RESULTS: Anterior space (AS), superior space (SS), and posterior space (PS) joint space measurements at T0 between the FPXB side and contralateral side demonstrated no statistically significant differences. After RME treatment (T1), all three joint spaces increased on both the FPXB side and the non-crossbite side. However, differences were statistically significant only for the SS when comparing the two sides at T1. SS increased more than AS and PS in the non-crossbite condyle (0.28 mm) and FPXB condyle (0.37 mm), and PS increased only on the FPXB side (0.34 mm). CONCLUSIONS: There were no statistically significant differences in condyle position within the glenoid fossa between the FPXB and non-crossbite side before treatment. Increases in joint spaces were observed after treatment with RME on both sides. These changes were, however, of small amounts.

To evaluate the apoptosis involvement in the angiogenesis as a self-limiting process in patients with temporomandibular joint (TMJ) degenerated disc vessels, we assessed, by immunohistochemistry, the detection of TRAIL, its death receptor DR5 and caspase 3. TRAIL, its death receptor DR5 and caspase 3 expression were studied by immunohistochemistry in 15 TMJ discs displaced without reduction and in 4 unaffected discs. These apoptosis molecules were detected in the intima and media layers of newly formed vessels affected discs. In conclusion, vessels apoptosis activation in TMJ disc with ID could be regarded as a self-limiting process that try to leads to vessel regression; in this way an inhibition of angiogenic vessels may prove a key strategy in limiting pathological angiogenesis, by cutting off blood supply to tumors, or by reducing harmful inflammation.

Craniofacial morphology of patients with nevoid basal cell carcinoma syndrome (NBCCS) has sometimes been reported at clinical examination, but any investigation has described it on the basis of cephalometric measurements.The purpose of this study was to conduct a cephalometric analysis of patients with NBCCS and to compare measurements with non-NBCCS subjects of similar ages, to elucidate if there is any relationship between NBCCS and craniofacial morphology.The study population consisted of 14 adult patients (9 men and 5 women), ranging in age from 18.2 to 56.8 years, with the diagnosis of NBCCS, with good-quality lateral cephalometric radiographs, and 14 adult healthy patients matched for age and sex to the NBCCS group. Cephalometric measurements were carried out on radiographs, and measurements of angles and distances were performed.Statistical differences between NBCCS subjects and controls were observed. Data analysis displayed that the measurements of the anterior cranial base (P

Objective: To test the null hypothesis that there is no increased prevalence of skeletal anomalies and/or normal variants as evidenced by the cephalometric radiographs of patients with palatally displaced canines (PDC). Materials and Methods: The treatment records of 38 white subjects between 14 and 20 years old with PDC were collected and evaluated retrospectively. Inclusion criteria for the study required that the case records include good-quality panoramic radiographs and lateral cephalometric radiographs with the first four cervical vertebrae clearly visible. The anomalies recorded for each case included sella bridge, atlanto-occipital ligament calcification or ponticulus posticus, and posterior arch atlas deficiency. A control group consisted of 70 consecutively treated subjects who had no other dental anomalies and whose maxillary canines had erupted normally. Fisher's exact test and Pearson's chi-square test were used to determine possible statistically significant differences in the incidence of skeletal anomalies and/or normal variants between the group of patients with PDC and the control group. Results: The prevalence of skull anomalies and normal variants seen in cephalometric radiographs was increased in patients with PDC. Because of the presence of ponticulus posticus (Pearson's chi-square, P < .050; Fisher's exact test, P < .052), sella bridge (Pearson's chi-square, P < .042; Fisher's exact test, P < .042), and posterior arch deficiency (Pearson's chi-square, P < .047; Fisher's exact test, P < .039), statistically significant differences were observed between subjects with PDC and the control group. Conclusions: The null hypothesis was rejected. There is an increased prevalence of skull skeletal anomalies and/or normal variants in patients with PDC.

To evaluate the reliability of landmark identification in posteroanterior cephalometrics.A literature search was conducted to identify all articles concerning landmark identification error in the frontal radiograph. Electronic databases (PubMed, Web of Science, Cochrane Database, PubMed Central, and HubMed) were searched. Abstracts that appeared to fulfill the initial selection criteria were selected, and the full-text original articles were then retrieved and analyzed. Only articles that fulfilled the initial selection criteria were finally considered. Their references were also hand searched for possible missing articles from the database searches.Twelve abstracts met the initial inclusion criteria, and these articles were retrieved. From these, eight were immediately rejected because of methodological issues. Only the four articles remaining seemed to fulfill the selection criteria, but two articles were later rejected, one because no landmark identification error mean values were provided and the other because of the sample. Only one article fulfilled the inclusion and exclusion criteria of this study. Midline landmarks were more reproducible than bilateral skeletal landmarks.Only one study fulfilled the additional inclusion and exclusion criteria. Few studies exist about the random error in localization of landmarks in posteroanterior cephalograms, and several methodological issues affected these few studies. Thus, future well-designed studies are needed to allow the orthodontist to choose the most appropriate cephalometric analysis.

Calcification of the interclinoid ligament (ICL) of the sella turcica, or sella turcica bridging, has been associated with severe craniofacial deviations. Despite no comprehensive study on the sella turcica bridge, a relationship with tooth and eruption disturbances has been reported. In order to investigate whether congenital absence of the second mandibular premolar, or the presence of a palatally displaced canine (PDC), is associated with sella bridging, a retrospective study was performed. Lateral cephalometric radiographs from 20 males and 14 females, aged between 8 and 16 years, with a PDC and second mandibular premolar aplasia were reviewed and compared with a control group. A standardized scoring scale was established to quantify the extent of a sella turcica bridge from each radiograph (no calcification, partially calcified, and completely calcified). The prevalence of complete calcification of the ICL in adolescents with dental anomalies was equal to 17.6 per cent, while an incidence 9.9 per cent was found in the control group. A partially calcified sella turcica was observed in 58.8 per cent of adolescents with dental anomalies compared with 33.7 per cent in the control group. The association between the degree of calcification of the ICL and the presence of dental anomalies in the studied adolescents was statistically significant according to chi-square statistics (P = 0.004). This was confirmed by Fisher's exact test (P = 0.003). According to these findings, the prevalence of a sella turcica bridge in adolescents with dental anomalies is increased, while age and gender do not greatly influence ossification of the ICL. The very early appearance during development of a sella turcica bridge should alert clinicians to possible tooth anomalies in life later.

Introduction: During orthodontic treatment, the early response of periodontal tissues to mechanical stress involves several metabolic changes that allow tooth movement. Many studies have evaluated these modifications through the analysis of various metabolites released into gingival crevicular fluid (GCF). The purpose of this investigation was to evaluate matrix metalloproteinase (MMP)-1 and MMP-2 in the GCF of human teeth exposed to orthodontic force on both the tension and compression sides in the initial phase of orthodontic tooth movement. Methods: GCF samples were obtained from 11 healthy orthodontic patients (8 girls, 3 boys; age, 13-15 years; mean, 13.9 years) who needed their 4 first premolars extracted for orthodontic reasons. In each patient, the left maxillary canine having the fixed orthodontic appliance was used as the test tooth, and its antagonist, with no appliance, was the control tooth. Orthodontic force was applied by using a Sentalloy coil-spring (GAC International, Bohemia, NY) of 150 g. The GCF sampling on the mesiobuccal and distobuccal aspects of each experimental and control tooth was performed at specific times up to 8 hours with paper strips. Processing was carried out with western blot analysis to detect MMP-1 and MMP-2 levels on the compression and tension sides. Results: Compression force induced a significant increase of MMP-1 protein after 1 hour; the increase lasted until the third hour of force application and disappeared thereafter. The tension force induced significantly increased levels of the MMP-1 protein after just 1 hour of force application. MMP-2 protein was induced by compression and increased significantly in a time-dependent fashion, reaching a peak after 8 hours of force application. On the tension side, MMP-2 was significantly increased after 1 hour but gradually returned to basal levels within 8 hours. Conclusions: Orthodontic forces affect both MMP-1 and MMP-2 protein levels on the compression and the tension sides, although to different extents, whereas MMP-1 and MMP-2 protein levels change in a time-dependent fashion.

Cephalometric analysis has a key role in orthodontic clinical practice and research. The skills needed to accurately trace radiographs can be acquired only through practice. We developed an interactive, Internet-based system to help students hone their cephalometric tracing skills. The online system allows students to practice any time and at their own pace, and receive immediate graphical feedback on the quality of their work. It also allows instructors to update the collection of cases available to students for practice.

Vascular endothelial growth factor (VEGF), also known as vascular permeability factor (VPF), is a multifunctional cytokine. It is overexpressed in several conditions, which are characterized by vascular hyperpermeability and angiogenesis. In this investigation, we have evaluated the possibility that VEGF/VPF could be expressed in periapical lesions. We studied 17 periapical granulomas and 6 periapical cysts by immunohistochemistry. An immunopositive reaction for VEGF/VPF was observed in all 23 periapical lesions; however, the intensity of immunostaining by anti-VEGF antibody varied according to histopathological findings. In periapical granulomas without epithelium, almost all of the inflammatory cells were immunoreactive to anti-VEGF/VIP antibody. In periapical granulomas, which had rests of Malassez in them, some inflammatory cells were stained. On the other hand, epithelial cells always were stained by VEGF/VPF antibody, both in periapical lesions with epithelium and in radicular cysts. This study demonstrated that periapical lesions express VEGF/VPF, although with some differences in cell immunolabeling, which correlated to the lesions' stages of development. Initially, VEGF/VPF would assure angiogenesis and vascular hyperpermeability, resulting in accumulation of inflammatory cells, later it could be involved in cyst fluid accumulation. We hypothesize, therefore, that VEGF/VPF expression plays an important role in the pathogenesis of periapical granulomas and enlargement of radicular cysts by several mechanisms.

A high density of blood vessels is found in specimens of temporomandibular joint (TMJ) disc at any stage of internal derangement of the joint, but the factors responsible for angiogenesis in the disc have not been described. The purpose here was to investigate, in human TMJ discs, the expression of vascular endothelial growth factor (VEGF), a multifunctional cytokine that contributes to angiogenesis. Specimens, free of significant morphological alterations and with varying degrees of disc tissue degeneration/regeneration, were studied by immunohistochemistry for VEGF in order to correlate immunohistochemical with histopathological findings. In normal discs and discs with minor pathological changes, fibroblast-like cells, fibrochondrocytes and chondrocyte-like cells were either not or only weakly immunostained by VEGF antibody. In disc specimens from internal derangement of the TMJ with significant tissue degeneration/regeneration, VEGF was consistently expressed. In these specimens, immunoreaction products for VEGF were observed both in the disc and in the endothelial cells of newly formed vessels. This VEGF immunolocalization is consistent with the stimulation of angiogenesis and the morphogenesis and differentiation of chondrocytes. Therefore VEGF expression by disc chondrocyte-like cells might reflect the action of the cytokine as an inducer of angiogenesis and as an autocrine signal for cells of the chondrogenic lineage.

Heat shock protein (HSP) 27 is a member of the small HSP family that plays a part in the regulation of epithelial cell growth and differentiation, wound healing, apoptosis and cell protection against inflammatory cytotoxicity mediators. Thus the expression of HSP27 was investigated immunohistochemically in periapical granulomas with epithelial rests of Malassez and in radicular cysts. Anti-HSP27 mouse monoclonal antibody and peroxidase-labeled streptavidin-biotin standard technique were used to study the expression of HSP27. Proliferating epithelial cell rests, and islands of epithelium and epithelial lining of microcysts strongly reacted throughout all layers, whereas radicular cysts epithelial lining presented mainly a moderate suprabasal staining pattern. However both the proliferating epithelial cell rests and the radicular cysts shared an over-expression of HSP27 immunostaining intensity in coincidence with the presence of local infiltration of immune cells. HSP27 may play several roles in periapical lesions that include contributing to the migration of epithelial cell rests and an increased resistance both to necrotic and apoptotic cell deaths.

The acrofacial dysostoses (AFDs) are a heterogeneous group of disorders combining defects of craniofacial and limb development. The predominantly preaxial form is called Nager AFD, the predominantly postaxial form of AFD (POADS) is also known as the Genee-Wiedemann or Miller syndrome. The former appears to be about twice as common as the latter with well-documented autosomal dominant and recessive occurrences in both conditions. Only 1 AD occurrence of POADS is known, but 5 sets of sibs are suggestive of AR inheritance. Heterogeneity of apparently nonsyndromal AFD of both types is powerful support for the hypothesis that the AFDs are polytopic field defects arising during blastogenesis. Six other previously described forms of AFD include the AFD syndrome of Kelly et al. (AR), the Rodriguez or Madrid form of AFD (AR or XLR), the Reynolds or Idaho form of AFD (AD), the Arens or Tel Aviv type of AFD (AF?), the presumed AR AFD syndrome of Richieri-Costa et al., and the AD Patterson–Stevenson–Fontaine syndrome. Here we review the AFDs and report on a previously apparently undescribed autosomal or X-linked dominant form of AFD with mental retardation in a Sicilian mother and her 4 sons. © 1993 Wiley-Liss, Inc.

The original article to which this Erratum refers was published in Am J Med Genet 110:400–403.

Heat shock proteins (HSPs) are believed to represent a cellular stress response mechanism that protects intracellular proteins from damaging events. Some studies have demonstrated an enhanced expression of large-molecular-weight HSPs in diseased systematic joints. Small heat shock proteins, and among these HSP27, have been studied to a lesser extent. HSP27 has cytoprotective and biosynthetic functions within chondrocytes, and it is an estrogen-associated protein that is under hormonal modulation. To improve understanding at a molecular level of the pathophysiology of certain temporomandibular joint disorders, the authors carried out this immunohistochemical study to assess the presence of HSP27 in human TMJ discs. Twelve adult human TMJ discs (10 diseased and 2 healthy discs) and 5 TMJ fetal human discs were used in this study. Adult discs and TMJ tissues of human fetuses were fixed in 10% buffered formalin. Samples were then processed for histologic examination. Sections were immunohistochemically stained using the streptavidin-biotin detection method. No reaction product for HSP27 in the discs of fetuses was noted. HSP27 was weakly expressed in normal TMJ discs and highly up-regulated in discs of patients showing new vessel formation and chondroid metaplasia. Any correlation between gender and HSP27 was found in the sample, being the up-regulation of HSP27 related mostly to major histopathological changes. This different pattern of HSP27 immunostaining in human TMJ discs detected in the authors' specimens suggests that the expression of this small HSP is functionally modulated. In fact HSP27 up-regulates in internal derangement specimens with major histopathological changes; on the other hand, it is not expressed or only weakly expressed in TMJ discs of fetuses and normal TMJ discs.