The occurrence of a fibro-osseous lesion and multiple dental anomalies in a patient with the Greig cephalopolysyndactyly syndrome

The Greig cephalopolysyndactyly syndrome is an uncommon dysmorphic syndrome characterized by preaxial and postaxial polysyndactyly and minor craniofacial anomalies. It has an autosomal dominant inheritance. A review of the literature has failed to show documentation of any dental or oral abnormalities. Therefore, we report on a patient with Greig syndrome who had a maxillary fibro-osseous lesion and multiple dental and oral abnormalities.     

The mechanism of action of chlorhexidine

Controversy exists concerning the mode of action of chlorhexidine in plaque inhibition. This study attempted to determine whether an oral reservoir of chlorhexidine was necessary for plaque inhibition. Plaque growth on enamel under the influence of topically applied or rinsed chlorhexidine was closely monitored by clinical scoring, bacterial culturing and scanning electron microscopy. Thus, 3 subjects wore removable acrylic appliances containing enamel inserts. In the first regimen, inserts on one side of the appliances were exposed to 0.2% chlorhexidine and on the other, water for 1 min twice a day for 14 days. In the second regimen, subjects rinsed with 0.2% chlorhexidine for 1 min twice a day for 14 days with the appliances in situ. Results demonstrated that plaque growth assessed by the 3 study methods was very small on chlorhexidine-treated inserts by comparison with water-treated specimens. Importantly, inserts treated with chlorhexidine topically or by rinsing could not be distinguished by any method of evaluation. It is concluded that chlorhexidine achieves plaque inhibition as a result of an immediate bactericidal action during the time of application and a prolonged bacteriostatic action as a result of adsorption to the pellicle coated enamel surface. Consistent with other clinical studies, it is apparent that a progressively desorbing oral reservoir of antiseptic is not the mechanism by which chlorhexidine achieves plaque inhibition on teeth.     

Cyclic changes in the properties of maturing enamel in the bovine permanent incisor as revealed by glyoxal bis(2-hydroxyanil) staining

Staining patterns of the surface and interior of maturing enamel of these tooth germs were examined using the glyoxal bis(2-hydroxyanil) (GBHA) solution which chelates with calcium loosely bound to hydroxyapatite to form insoluble red precipitates. An intense red, band-like pattern of GBHA staining, 1-2 mm wide, first appeared on the incisal portion of lingual enamel surface as complete loops, concentrically arranged; these gradually increased in number. Most of the later-formed bands encircled the entire periphery of the maturing enamel surface. GBHA also revealed reactive areas on the labio-lingual, cut and ground surface of maturing enamel, corresponding exactly to the surface GBHA bands. GBHA did not stain EDTA-etched surface enamel, but did reveal regular staining patterns on the ground surface, disclosed after EDTA treatment. These observations suggest an intimate correlation between the properties of interior and surface enamel, at least with regard to the state of local calcium. The maturation of bovine incisor enamel may start at the lingual aspect of the tooth crown.     

Anterior disk displacement of the temporomandibular joint

Summary In order to examine the diagnostic significance of typical clinical symptoms in temporomandibular joint (TMJ) disorders for diagnosis of anterior disk displacement, clinical findings were compared with the degree of disk displacement in 84 TMJs of 59 patients with TMJ disorders, who were examined clinically and by means of magnetic resonance imaging (MRI). The control group consisted of 31 subjects with no TMJ symptoms. No significant correlation between the degree of anterior disk displacement and palpation pain of the masticatory muscles or clicking/crepitus of the TMJ could be found. Joint clicking was observed in 65% of patients with TMJ symptoms in normal disk position (NDP). The percentage of joint clicking was almost the same in patients with anterior disk displacement with reposition (ADWR) (68%). There were significant correlations between active mouth opening and disk position as well as between a history of pain and disk position. Patients with NDP and ADWR had almost identical mouth opening values: 48 (±5) mm and 46 (±5) mm respectively. In contrast to these groups the mean values decreased significantly to 42 (±6) mm in patients with anterior disk displacement without reposition (ADWOR). There were no significant correlations between occlusal findings (centric relation and habitual relation, early occlusal contacts, abrasion facets) and disk position when viewed either collectively or individually.

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Anteriore Verlagerung des Discus articularis des Kiefergelenkes

Zusammenfassung Zur Überprüfung der Wertigkeit typisch klinischer Symptome für Funktionsstörungen zur Diagnose von Diskusverlagerungen wurden 84 Kiefergelenke von 59 Patienten mit Funktionsstörungen und 31 Kiefergelenke von klinisch asymptomatischen Probanden mittels Magnetresonanztomographie (MRT) untersucht und die einzelnen klinischen Befunde der Art der Diskusvergerung gegenübergestellt. Zwischen dem Grad der anterioren Diskusverlagerung und einem positiven Palpationsbefund der Kaumuskulatur, einem Palpationsschmerz der Kiefergelenke und dem Auftreten von Gelenkgeräuschen ergaben sich keine signifikanten Beziehungen. Bei funktionsgestörten Patienten zeigte sich mit 65% bei normaler Diskusposition (NDP) fast ebenso oft ein Gelenkknacken wie bei Patienten mit anteriorer Diskusverlagerung mit Reposition (VMR, 68%). Signifikante Beziehungen bestanden zwischen aktiver Mundöffnung und Diskusposition sowie anamnestisch angegebenen Schmerzen und Diskusposition. Während bei NDP- und VMR-Patienten mit 48 (±5) mm und 46 (±5) mm ähnlich hohe Mundöffnungswerte vorlagen, nahmen diese bei Patienten mit anteriorer Diskusverlagerung ohne Reposition (VOR) auf 42 (±6) mm signifikant ab. Okklusale Befunde (Differenz zwischen zentrischer und habitueller Okklusion >2 mm, vorzeitige okklusale Kontakte, Auftreten von Schliffacetten) zeigten in ihrer Gesamtheit wie auch in der Einzelbetrachtung keine signifikanten Beziehungen zur Diskusposition. Die Ergebnisse zeigen, daß für die Diagnostik von Funktionsstörungen allgemein als bedeutend anerkannte klinische Symptome in bezug auf die Art und das Vorliegen einer anterioren Diskusverlagerung allein keine sichere Aussage zulassen. Dies betrifft besonders die anteriore Diskusverlagerung ohne Reposition. Gleichzeitig wird die Zuverlässigkeit der MRT für die klinisch oft schwierige Diagnostik der Bestimmung der Diskusverlagerung bei Patienten mit Funktionsstörungen des Kausystems bestätigt.