bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultrastructural vascular changes in pressure zones of rat molar periodontium incident to orthodontic movement
Authors: RYGH PER
Published: October 2007

abstract – Changes in the vasculature of the periodontal ligament of teeth subjected to orthodontic forces have been described. The purpose of the present study was to characterize these changes at the ultrastructural Ievel. In 55 rats, one maxillary first molar was moved buccally by means of a fixed appliance, using forces of 5–25 g. Animals were sacrificed after periods of 30 min to 28 d. The experimental teeth with surrounding periodontal tissues were obtained and processed for electron microscopy. Retardation and stasis of the blood flow occurred within 30 min after force application. After 2 h the vessels in the pressure zone appeared extended and packed with red blood cells which often attained a polygonal shape. After 2 h to 3 d, fragmentation of the erythrocytes occurred. Various patterns of erythrocyte breakdown were observed. Most often the erythrocytes changed into irregularly contoured fragments of various electron densities. Occasionally the fragments exhibited a substructure indicating transformation to a crystalline substance. Also, disintegration of the walls of the blood vessels and release of their contents into the surrounding fibrous tissue was observed after 1–7 d. Regenerative processes were predominating in the 7–28 day specimens.
Lysozyme (muramidase) activity of leukocytes and exfoliated epithelial cells in the oral cavity
Authors: RAESTE ANNA‐MAIJA
Published: October 2007

abstract – Lysozyme (muramidase) activity was determined in leukocytes and in exfoliated epithelial cells collected from the mobile mucus phase of the oral cavity. With the method adopted exfoliated epithelial cells could be separated from leukocytes with a contamination of less than 1 %. With microbiologic tests none of the epithelial cells examined showed lysozyme activity. But on biochemical assay a very low Ievel of activity was observed, just at the limits of sensitivity of the method used. This amount, 0.2 μg/106 cells (hen eggwhite lysozyme, HEL), may have been due to contamination with bacteria. The lysozyme activity of oral PMN leukocytes was 5.65 ± 1.64 μg/106 cells (HEL). The loss of activity as compared with the PMN leukocytes of blood was roughly proportional to the injuries observed in the cells. It is inferred that injured neutrophils release lysozyme, and that oral leukocytes are one of the sources of the lysozyme present in saliva.
Chlorhexidine as a denture disinfectant in the treatment of denture stomatitis
Authors: BUDTZ‐JöRGENSEN E. , LöE HARALD
Published: October 2007

abstract – In a double‐blind study conducted on 53 wearers of complete dentures, application of 2 % chlorhexidine gluconate to the fitting surface of the maxillary denture for 2 weeks was found to produce a significant amelioration of inflamed tissues beneath the denture. Mycelium was eliminated in 90 % of the patients, as evaluated by palatal smears. Five weeks after the treatment was terminated the candida infection of the palatal mucosa was re‐established in all but one of the patients, probably because disinfection of the maxillary denture did not effect a complete suppression of candida growth, neither in the palate nor in other sites of the oral cavity. It is concluded that chlorhexidine gluconate is an appropriate alternative to specific antimycotic drugs for the treatment of palatal can didiasis. However, until conclusive evidence has been produced that prolonged mouth‐rinsing with chlorhexidine is biologically acceptable, it should be used primarily as a denture disinfectant, whereas specific antimycotic drugs should be used to eradicate candida residing on the oral mucosa.
Mandibular movement capacity in the rat
Authors: RISNES STEINAR
Published: October 2007

abstract – The capacity area of mandibular movements was reconstructed in two fully grown male rats immediately after the rats were killed with ether. The tips of the mandibular incisors were used as recording markers. The shape and dimensions of the capacity area are discussed in relation to joint morphology and habitual jaw movements.
A method for radiographic assessment of periodontal bone support following orthodontic treatment
Authors: SJÖLIEN TROND , ZACHRISSON BJÖRN U.
Published: October 2007

abstract – A method for radiographic assessment of periodontal bone support and apical root resorption was developed and evaluated. Tests on inter‐ and intra‐radiographer variability revealed little variation between duplicate exposures. A high degree of intra‐examiner reproducibility in assessing bone height and tooth length was demonstrated.
Preservation and demonstration of mast cells in human apical granulomas and radicular cysts
Authors: MATHIESEN ÅGE
Published: October 2007

abstract – The investigation concerns the preservation and demonstration of human mast cells in undemineralized material. The material comprised human apical granulomas and radicular cysts dissected from extracted teeth or obtained by apicoectomy and cyst removal. Chronically inflamed human gingiva, rat tongue, and rat peritoneum served as control tissues. The following fixations were tested: 4% formaldehyde solution buffered to pH 7.2, Newcomer's fluid, and a 4% aqueous solution of basic lead acetate with formalin 1:10 added. The following dyes and fluorochromes were tested: toluidine blue in various concentrations and at various pH values, Astra‐blue, the esterase substrate naphthol‐AS‐D‐chloroacetate in combination with GBC, acridine orange in various concentrations and at various pH values, berberine‐sulfate, and thioflavin T. Abundant mast cells were demonstrated in all granulomas and cysts with at least one of the staining methods tested. A 4% lead acetate solution with formalin added proved the best fixative for the preservation of the human mast cells, whereas staining with Astra‐blue appeared the superior technique for demonstrating the human mast cells. Acridine orange showed the best secondary fluorescence of the fluorochromes tested. The best results with this dye were obtained using a 0.03% solution in 5% AlSO4.
Induction of heterotopic bone formation by demineralized dentin: an experimental model in guinea pigs
Authors: BANG GISLE
Published: October 2007

abstract – The present investigation was carried out to establish an experimental model for the induction of heterotopic bone formation by demineralized dentin in guinea pigs. A total of 168 samples of allogenic dentin treated in different ways, as well as eight samples of striated muscle and eight samples of achilles tendon, were implanted in the abdominal muscles or subcutaneously in 43 male guinea pigs. Eight sham operations were also performed. The data indicated that allogenic dentin demineralized in 0.2 N HCl at 4°C for 48 h, lyophilized and sterilized in ethylene oxide gas, consistently induced heterotopic bone formation in about 70% when placed subcutaneously or in a pouch in the abdominal muscles of young male guinea pigs. Neither HCl‐treated muscles and tendon nor sham operations gave any new bone formation.
Cellular immunity in acquired candidiasis of the palate
Authors: BUDTZ‐JöRGENSEN E.
Published: October 2007

abstract—In vitrocellular hypersensitivity and agglutinating antibody toC. albicanswas assessed in 180 subjects of whom 55 were patients withCandida‐induced denture stomatitis (25 with the generalized simple and 30 with the granular type) whereas 16 had traumainduced lesions in the palatal mucosa. Patients with other candidal manifestations, such as cutaneous candidiasis (5), vaginal candidiasis (3),Candidaleukoplakia (1), chronic mucocutaneous candidiasis (2), and appropriate controls were included in the study. Using the leukocyte migration test, cellular hypersensitivity toC. albicanswas demonstrated in 76% of the patients with the generalized simple type of denture stomatitis and in most of the patients with vaginal or cutaneous candidiasis. However, only 28% of the patients with the granular type of denture stomatitis and none of those with mucocutaneous candidiasis showed significant inhibition of migration. Upon antifungal therapy of 13 patients, cellular hypersensitivity was restored. The increase of the cellular immune response toC. albicanswas most pronounced for the granular type of denture stomatitis. In the infected patients an inverse relationship was demonstrated between cellular hypersensitivity and agglutinating antibody titer toC. albicans. The immediate increase in leukocyte response toC. albicansthat was demonstrated after antifungal therapy was taken as indirect evidence that aCandidainfection may lead to a suppression of the systemic cellular immune response toC. albicans.
A new methodology for study of plaque formation in natural human fissures
Authors: FOLKE LARS E. A. , SVEEN ODD B. , THOTT EVA K.
Published: October 2007

abstract— A model system has been developed to study the formation of plaque in natural, human, enamel fissures. Surgically removed, fully impacted third molars were used. The occlusal two‐thirds of the crowns were separated from the teeth and sonicated. The specimens were then placed on a bridge or an acrylic appliance and exposed to the oral environment for 0, 1, 2, 3 and 5 d. The experimental fissures were then subjected to microbiologic and ultrastructural analysis. The results documented that fissure plaque could be conveniently sampled for subsequent microbiologic analysis using this technique. The microbiologic composition of developing fissure plaque was verified by ultrastructural data.
A follow‐up study of post‐ or pinretained amalgam fillings with special reference to possible corrosion
Authors: SIMONSEN T. LETH , NILSEN G. NORMANN , HALS E.
Published: October 2007

abstract— The aim of the present study of a student‐treated patient material was to follow‐up extensive amalgam fillings retained with Dentatus® screwposts or stainless steel pins, because some authors have claimed that these methods may give rise to corrosion and subsequent root fracture. During the years 1963–72 Dentatus screwposts had been inserted in 73 endodontically treated teeth which, over a period of 5 years, had been examined once a year. During the same period 78 Unitec® stainless steel pins were inserted parapulpally in 43 teeth. Average observation time for teeth with screwposts or pins was around 4 1/2 years. The clinical investigation which followed written standards concerned 7 subjective and 10 objective symptoms, and the radiographic investigation, based on a minimum of 4 projections for each tooth, included 7 criteria. Neither the clinical nor the radiographic investigations showed direct or indirect signs of corrosion or its sequelae. Changes giving rise to suspicion could in all cases be traced back to causes other than corrosion.
Chemotactic activity in experimental gingivitis
Authors: HELLDÉN L. , KAHNBERG K.‐E.
Published: October 2007

abstract— Forty‐eight dental students were screened regarding the rate of plaque formation. The four most rapid (RPF‐group) and the four slowest (SPF‐group) plaque formers were selected and compared as to: (1) the development of gingivitis during a 14‐day period without oral hygiene, (2) the chemotactic activity elaborated by (a) gingival crevicular material (GCM) sampled 24 h after withdrawal of oral hygiene measures and (b) 4‐ and 8‐day‐old plaques, and (3) permeability‐inducing factors in 4‐ and 8‐day‐old plaques. The Gingival Index, Plaque Index and flow of gingival fluid were used for assessing plaque formation and gingivitis development. The chemotactic activity was estimated with the use of Boyden's in vitro model, and subcutaneously implanted wound chambers were used for demonstrating change in vascular permeability. It was found that: (1) individuals vary considerably with regard to the rate of formation of dental plaque, (2) gingivitis developed faster in the RPF group than in the SPF group, (3) GCM sampled already 24 h after cessation of oral hygiene yielded higher chemotactic activity in the RPF group than in the SPF group, and (4) the RPF and SPF groups did not differ from one another regarding chemotactic activity or permeability‐inducing activity of equal amounts (wet weight) of plaque.
Histologic variations in the pulp of intact premolars from young individuals
Authors: GVOZDENOVIC‐SEDLECKI SNEZANA , QVIST VIBEKE , HANSEN H. P.
Published: October 2007

abstract— The investigation included 54 intact premolars from children between 11 and 15 years of age. The teeth were scheduled to be extracted for orthodontic reasons. The extraction was performed with local anesthesia and the teeth were fixed in 10% formalin for 2, 4 or 8 d. The intention of this investigation was to show the histologic variation of the pulpal condition in such clinically intact teeth. The investigation included predentin, odontoblast layer, Weill's zone, cell‐rich layer, and the central part of the pulp. The results showed that there was a great variation in the width of predentin in the column area, and that almost all teeth had vacuoles in the odontoblast layer and inflammatory cells in the cell‐rich layer. An indistinct Weill's zone and reticular atrophy in the central part of the pulp were common findings. Therefore the above‐mentioned “changes” cannot be considered valid criteria of iatrogenically induced reactions in the pulp. In the coronal pulp the number of rows of odontoblast nuclei was constant. No inflammatory cells were found in the odontoblast layer and only a few in the central part of the pulp. Consequently, changes in these items are considered reliable criteria of pulpal reactions following exogenic injuries.
The application of twin methods in orthodontic research
Authors: SCHOUBOE KIRSTEN , HAUGE MOGENS
Published: October 2007

abstract— The relative importance of genetic and environmental factors in the development of the facial skeleton was studied in a radiographic investigation of 19 monozygotic and eight dizygotic twin pairs by means of comparative analysis.
A zinc‐copper phase in dental silver amalgam alloy
Authors: JENSEN S. J. , OLSEN K. B. , UTOFT L.
Published: October 2007

abstract— The quaternary system Ag‐Cu‐Sn‐Zn has been investigated in the region Ag 64–72, Cu 0–6, Sn 22–32, Zn 0–6 weight‐% using X‐ray diffraction, metallographic and electron microprobe technique. The presence of a phase with γ‐brass structure (Cu5Zn8) containing about 45% Cu, 27% Zn, 18% Sn and 10% Ag was detected.
Silicate cement in a cell culture system
Authors: HELGELAND KRISTEN , LEIRSKAR JAKOB
Published: October 2007

abstract— Human epithelial cells (NCTG 2544) were grown as monolayer cultures in the presence of silicate cement disks (Bio‐trey 9®). A cytotoxic effect was found on the surface of the disks after 24 h, whereas a corresponding effect was obvious around the disks after incubation for 3 d. In the silicate cement cultures more glucose was utilized and more lactate formed per cell than in control cultures. In the presence of silicate cement, pH of the culture medium decreased during incubation, reaching 6.3–6.4 after 6 d. Phosphate, silicon, zinc, and fluoride were released into the medium from the silicate cement disks. The medium concentration of sodium, however, remained constant, and aluminum was not detected. The concentrations of calcium and magnesium decreased, and experiments with 45Ca showed that calcium was bound to the silicate cement disks.
Comparison of different methods in active and passive recording of the retruded position of the mandible
Authors: HELKIMO MARTTI , INGERVALL BENGT , CARLSSON GUNNAR E.
Published: October 2007

abstract— Six methods for active and passive recording of retruded position of the mandible were compared in an investigation carried out on 10 male volunteers, aged 22 to 27. The position of the mandible was recorded with the intraoral graphic method. The precision of the recording of the retruded position was highest when recorded by passive hinge movement, and lowest when recorded by active hinge movement and active retrusion from habitual occlusion. No differences in the anteroposterior position of the mandible in the retruded position were found between the active and passive recordings with the exception of the socalled “moderate chin guidance” which resulted in a more anterior mandibular position than the other methods, but still in the retrusive area, i.e. posterior to habitual closure.
Blood flow in human temporal muscle during tooth grinding and clenching as measured by 133Xenon clearance
Authors: PETERSEN F. BONDE , CHRISTENSEN L. VESTERGAARD
Published: October 2007

abstract— Six healthy human subjects performed grinding and clenching of teeth, to assess if pain releasing and strenuous muscular exercise causes a decrease or total stop of the blood flow through the temporal muscles, as measured by 133Xenon clearance. The mean blood flow/volume of muscle tissue was 25.4 ml×min−1×l−1 during rest, whereas the mean flow was 101.8 ml×min−1×l−1 during grinding, and 62.9 ml×min−1×l−1 during clenching. It is suggested that facial pains induced by strenuous exercise of the jaw muscles are not due to ischemia. On the contrary, the blood flow seems to increase about 300% during grinding and about 150% during clenching.
Neutrophil chemotactic substances in different fractions of soluble dental plaque material
Authors: HELLDÉN LEIF , ERICSON THORILD , LINDHE JAN
Published: October 2007

abstract— Extracts of 4‐day‐old dental plaque were fractionated on Sephadex® columns (G‐10; G‐25; G‐200). Five fractions were selected from the protein and conductivity peaks obtained in chromatograms. The chemotactic activity elaborated by the fractions was tested in the Boyden's in vitro model system. The permeability altering capacity of the plaque fractions was tested in vivo in a wound chamber. The results from the in vitro experiments demonstrated that all fractions were chemotactic for rabbit neutrophil leukocytes. Substances of a low molecular size (mol. wt.∼5.000) elaborated, however, the peak chemotactic activity. The results from the in vivo experiments showed that the plaque fractions induced an increased (1) vascular permeability, and (2) emigration of leukocytes from a granulation tissue vasculature. The most pronounced emigration and exudation was induced by the low molecular size fraction (mol.wt.∼5.000).
Pulpal responses to “composite” dental materials lined with Tubulitec® or Dropsin®
Authors: ERIKSEN HARALD M.
Published: October 2007

abstract— Previous studies have shown that neither Tubulitec® nor Dropsin® produced serious changes in the dental pulp when used as liners under amalgam restorations. In the present investigation, based on 136 monkey teeth, the composite materials Addent Concise® and Adaptic® were shown to induce harmful inflammatory reactions in about one third of the teeth. Tubulitec reduced this irritative response significantly but not totally. The protective effect demonstrated from a Dropsin lining was inferior to that provided by Tubulitec.
A histopathologic study of replanted teeth with superficially demineralized root surfaces in Java monkeys
Authors: NORDENRAM ÅKE , BANG GISLE , ANNEROTH GÖRAN
Published: October 2007

abstract— Since unmineralized tissues are supposed to possess a resistance to resorption, and demineralized dentin implants induce bone formation and may be remineralized, it was thought worthwhile to study the effect of superficial demineralization of the root surface prior to replantation of the maxillary incisors in 14 Java monkeys. The investigation showed that this treatment caused an accentuated resorption and ankylosis of the tooth as well as other pathologic changes in the periodontium. The technique neither improves the healing of the replanted tooth nor prolongs the survival time.
The radiosensitive stages of the rat incisor odontoblast as demonstrated by autoradiography
Authors: KOPPANG HANNA STRÖMME
Published: October 2007

abstract— Five μCi 3H‐glycine/g body weight were administered to six rats 30 min prior to, and to six rats 24 h after, exposure to a single head roentgen dose of 500 r. Autoradiographic investigations of the incisors demonstrated that the most radiosensitive cells, the preodontoblasts just prior to dentin production, proceeded to mantle dentin deposition while the cells were partially deprived of their capacity of circumpulpal dentin production. Slightly less sensitive were mantle dentin‐producing cells, the injury to which was also reflected as a partial lack of circumpulpal dentin production. The radiosensitive period (500 r) was approximately equivalent to a maximum of 48 h, and a minimum of 24 h.
Localization of fibrinolytic activity during tooth eruption in rat
Authors: MAGNUSSON B. , GUSTAFSSON G. T.
Published: October 2007

abstract— The fibrinolytic activity of erupting teeth and their surrounding tissues was studied in 14 young rats with a modification of the histochemical fibrin slide technique. Frozen tape‐carried sections were coated with plasminogen‐rich or plasminogen‐poor fibrinogen, coagulated and incubated for 5 min to 1 h at 37°C. In the plasminogen‐rich fibrin, zones of lysis were produced within a few minutes, indicating release of tissue activator of the fibrinolytic system. Distinct fibrinolysis was localized to periosteum as well as to predentin and odontoblasts. Zones of lysis were also observed in relation to some vessel walls, but those of the pulp and the periapical connective tissue did not show any fibrinolytic activity.
Erythrocytic crystallization in rat molar periodontium incident to tooth movement
Authors: RYGH PER , SELVIG KNUT A.
Published: October 2007

abstract – From a material of 55 rats in which one maxillary molar had been moved buccally with a fixed orthodontic appliance, four specimens showing crystal‐like structures in pressure zones in the periodontal ligament were studied with the electron microscope. Crystals which occurred within the lumen of enlarged blood vessels appeared to have formed by direct transformation of erythrocytes. Crystals were also seen in extravascular locations. These particles seemed to have formed by solidification outside the blood vessels of substances released from degraded red blood cells. Many particles revealed a highly ordered internal structure thought to reflect the unit cell arrangement of the crystalline substance. On the basis of their location, internal structure, and the experimental circumstances, it was concluded that the crystals represented hemoglobin, rather than hematoidin, ferritin or hemosiderin. The study indicated that under the special conditions of pressure and hemostasis that existed in the periodontal ligament as a result of the experimental procedures, local degradation of erythrocytes occurred in a few specimens by mechanisms different from the physiologic breakdown of red blood cells in the spleen, liver and bone marrow.
Glycogen‐like granules in the apical area of young human and monkey pulps
Authors: SKOGEDAL O. , STENVIK A.
Published: October 2007

abstract – The periodic acid‐Schiff (PAS) and the alcian blue stainability of young human and monkey apical pulps have been studied, employing fresh‐frozen sections, as well as paraffin‐embedded sections of undemineralized and demineralized tissue. Two regions containing coarse magenta granules were observed in the growing pulp: a PAS‐positive zone adjacent to the periodontal tissue, and a proximally situated basophilic area. Clusters of magenta‐colored granules were present at the distal end of the pulp, and their number and size gradually diminished coronally. Amylase digestion indicated that the coarse granules may have been glycogen. The magenta granules were most easily demonstrated in formaldehyde vapor‐fixed frozen sections.
An evaluation of the duration and the results of orthodontic treatment
Authors: MYRBERG NILS , THILANDER BIRGIT
Published: October 2007

abstract – In 1,486 schoolchildren with various anomalies, different needs of orthodontic treatment, and treated with different techniques, the following variables were studied: uncompleted orthodontic treatment and reason for cessation of treatment, duration of active treatment, duration of retention period, complete registration period, results of treatment. One to five years after the end of treatment, 300 cases were examined regarding relapse, opinion of treatment, and opinion of the results of treatment.
Uptake and retention of fluoride by intact enamel in vivo after application of neutral sodium fluoride
Authors: BRUUN CARSTEN
Published: October 2007

abstract – The uptake and retention of fluoride in surface enamel in vivo after a single topical application of a neutral 2 % NaF solution was studied on the basis of 2–3 μm thick enamel biopsies from maxillary central incisors in adults and children. The biopsy technique included delimiting of the sampling area by means of abrasive‐resistant, adhesive tape, punched with perforations of known sizes admitting of two biopsies on different places on the same tooth surface. This method made it possible to calculate the depth of each biopsy and to perform the comparative studies with intradental control. The F uptake was estimated by comparing F concentrations in biopsies taken before and 1 week after topical treatment. In teeth of 10‐ to 11‐year‐old children the F concentration increased 259 ± 393 parts/106, which is statistically significant (P < 0.002). The mean uptake in teeth of adults, 22–27 years of age, was 179 ± 401 parts/106 which did not exhibit statistical significance (P > 0.10). The F concentrations in biopsies taken 1 week and 8 weeks after treatment from teeth in children were almost identical, indicating that the acquired F is firmly fixed in the enamel for 2 months or longer.
Enhanced emigration of crevicular leukocytes mediated by factors in human dental plaque
Authors: HELLDÉN LEIF , LINDHE JAN
Published: October 2007

abstract – The present investigation was performed to study whether a filtrate from human dental plaque when applied topically to the gingival margin enhances gingivitis. Four‐day‐old plaque was sampled from 20 dental students. The plaque samples were pooled, suspended in NaCl, homogenized, centrifuged and filtered. The capacity of the plaque filtrate to attract neutrophil leukocytes was determined by measuring the number of leukocytes (a) which migrated into wound chambers containing the filtrate and (b) which could be sampled from the gingival crevices of dogs and monkeys after repeated topical application of the filtrate to the gingival margin. Gingivitis was assessed by gingival exudate measurements. The results showed that substances present in human dental plaque are highly chemotactic for neutrophil leukocytes. The filtrate stimulated enhanced emigration of leukocytes into the gingival crevices and enhanced gingival exudation. The observations indicate that a plaque filtrate may enhance vascular and cellular changes similar to those seen in incipient gingivitis.
Glycosaminoglycan turnover and synthesis in the rat incisor pulp
Authors: LINDE ANDERS
Published: October 2007

abstract – The rate of in vivo turnover and in vitro synthesis of the glycosaminoglycans (GAGs; acid mucopolysaccharides) of the dental pulp loose connective tissue from rat maxillary incisors has been investigated by isotope methods. The biologic half‐life of 35SO4 in whole tissue digests was found to be 4.5 d. Of the sulfated GAGs the chondroitin‐4‐sulfate fraction was shown to have a more rapid turnover in vivo than the chondroitin‐6‐sulfate fraction, 4.1 and 5.2 d, respectively. The fraction containing keratan sulfate and glycoproteins had a biologic half‐life of 6.8 d. Slices of rat incisor pulps were incubated in vitro with 35SO4 and the rate of incorporation into the different GAG fractions was determined. After a lag‐phase of 15 min, this rate was linear with time. The chondroitin‐6‐sulfate fraction showed a more rapid uptake than the chondroitin‐4‐sulfate fraction, and the uptake by keratan sulfate + glycoprotein fraction was much lower. A similar in vitro experiment using [14C] acetate was performed. Contrary to the sulfate incorporation there was an extended lag‐phase, and the total incorporation was much lower.
Distribution of carbohydrates in demineralized paraffin sections of the rat jaw
Authors: BIRKEDAL‐HANSEN HENNING
Published: October 2007

abstract— The distribution of carbohydrates in paraffin sections of jaws from young rats was investigated with various histochemical methods (PAS, alcian blue, aldehyde fuchsin, and metachromatic staining) in combination with blocking, unblocking and extraction experiments. Glycoproteins and glycosaminoglycans, predominantly chondroitin sulfates, were found abundantly in teeth and surrounding structures. The results are discussed and correlated to recent biochemical findings.
Microbiologic study on developing plaque in human fissures
Authors: THEILADE ELSE , FEJERSKOV OLE , PRACHYABRUED WORALUGK , KILIAN MOGENS
Published: October 2007

abstract— Occlusal fissures from unerupted third molars were implanted in occlusal fillings in molars of six dental students. Two experiments were performed consecutively in each tooth. After 7 d in the mouth the fissure was removed, opened and dropped into a prereduced suspending medium and the contents suspended by ultrasound. In phase contrast microscopy the microflora consisted of 81–93% cocci and 7–19% rods. No fusiforms, filaments, spirilla, spirochetes or yeasts were seen. In Gram‐stained smears 81–96% of the bacteria were Gram‐positive. The anaerobic total viable counts (AnVC) were 1–33×106 per fissure. Streptococcal counts on Mitis Salivarius Agar constituted 29–60% of AnVC. In differential counts, S. mutans constituted 0–40%, S. sanguis 0–78% and S. salivarius 0–63% of the colonies present. Lactobacilli grew on Rogosa SL Agar from five of the subjects. In four of these, lactobacilli constituted 0.002–4% of the total viable counts, whereas in one sample they made up 65%. Hemophili isolated on chocolate agar containing bacitracin constituted 0–15% (median 0.7%) of the AnVC. Although the large variation indicates each fissure to be a separate ecologic system, it may be concluded that the flora differs from that of 7‐d dento‐gingival plaque at least by the absence of fusiforms, filaments, spirilla and spirochetes. The proportional distributions of Streptococcal species also differ from those reported for approximal and buccal plaque as well as for saliva.
Radiographic study of articular remodeling in the temporomandibular joint after condylar fractures
Authors: HOLLENDER LARS , LINDAHL LARS
Published: October 2007

abstract— A radiographic follow‐up of the temporomandibular joints in patients with condylar fractures revealed a frequent remodeling both of the condylar head and the glenoid fossa. A double contour of the fossa was the typical radiographic sign of remodeling. The occurrence of double contours was associated with displacement of the condylar head.
The oral health of children of dentists
Authors: AINAMO JUKKA , HOLMBERG STIG M.
Published: October 2007

ABSTRACT – In order to assess the long term effect of dental health education, the gingival state and dental conditions of 68 dentists' children aged 11.4 ± 3.4 years were compared with those of their age‐ and sex‐matched classmates from (a) parents with anoUier academic education of corresponding length, and (b) parents with no academic or high school education. A tendency for bleeding of the gingival margins at pressure was observed most often in children with non‐academic parents and was least frequent in dentists' children. The reported frequency of toothbrushing being the same in all three groups, it was suggested that the efficacy of the brushing among the dentists' children must be superior to that of the others. Also the DMF scores were found to be lowest in the group of dentists' children. The non‐academic children correspondingly presented the lowest frequency of intact first molars. The study confirmed the already accepted view that the educational level of the parents correlates positively with the dental health of their children. The finding that dentists' children are even better off than children of other academic parents was concluded to justify an intensification of dental health education in future dental care.
Relationship between tooth size and third molar agenesis
Authors: CHRISTENSEN H. C. , MELSEN B.
Published: October 2007

ABSTRACT – The hypothesis that third molar agenesis influences crown size of other permanent teeth was tested on a random sample of 300 children in the age group 14–16 years. The individuals were divided into four groups: Group A, full complement of teeth; B, a‐genesis of one or more third molars; C, agenesis of one or more third molars combined with agenesis of other teeth; D, agenesis of teeth other than third molars. Comparison of mesio‐distal crown diameter showed no significant differences between the groups of boys. In girls, differences in mesiodistal crown diameter were lestricted mainly to Groups A and D and thus were not influenced by the third molar. Calculation of asymmetry revealed no significant differences between groups with and without third molars, nor did the anterior ratio differ between these groups.
The structure of peripheral root dentin in young human premolars
Authors: FURSETH RANDI
Published: October 2007

ABSTRACT – The fine structure of peripheral root dentin in the cervical, midroot and apical areas has been studied by light and electron microscopy. Both methods have shown that the peripheral dentin at these three levels contains very few dentinal tubules. Further pulpally, dentinal tubules with a narrow lumen and highly mineralized peritubular areas were noted. In the cervical and middle part of the root a few small unmineralized areas were sometimes noted close to the cementodentinal junction, while in the apical part unmineralized areas were more numerous. Dentinal tubules were sometimes seen penetrating these areas. The unmineralized areas contained collagen fibers and had the shape of small interglobular areas.
Influence of chlorhexidine on in vitro uptake of fluoride in dental enamel
Authors: KIRKEGAARD E. , VON DER FEHR F. , RÖLLA G.
Published: October 2007

ABSTRACT – Chlorhexidine gluconate and sodium fluoride were found to be compatible in the concentration range of interest in clinical use. Admixture of chlorhexidine to sodium fluoride solutions did not interfere with the fluoride uptake in clinically intact premolars in vitro.
The frequency of Candida in oral lichen planus
Authors: HOLMSTRUP PALLE , DABELSTEEN ERIK
Published: October 2007

ABSTRACT – Histologic material of typical lichen planus lesions from 43 patients was studied. Two sections of each specimen were stained with hematoxylin‐eosin and 10 sections by the PAS method. Only 1 of 43 biopsies was invaded by Candida, and hyphae were present in all of the 10 PAS‐stained sections of this case. The results show that oral lichen planus has a considerably lesser susceptibility than oral leukoplakia to invasion by Candida albicans.
Histochemistry of the epithelium in excisional palatal wounds of guinea pigs
Authors: ANDERSEN L. , HEYDEN G. , FEJERSKOV O.
Published: October 2007

ABSTRACT –The palatal epithelium in excisional wounds of 19 guinea pigs has been studied for the activity of oxidative enzymes and the presence of lipids and glycogen at 12 h, 48 h, 120 h, and 240 h postoperatively. In five control animals the oxidative enzymes showed the highest activity in the basal and parabasal cell layers, except for the glucose‐6‐phosphate dehydrogenase reaction, which was most pronounced in the spinous cell layers. Unsaturated hydrophobic lipids were recorded in the superficial cell layers only. During wound healing the activity of oxidative enzymes disappeared in a triangular zone along the wound margin, indicating that functioning of the citric acid cycle, pentose shunt, and electron transport chain was markedly reduced. The migrating epithelial cells showed an activity similar to that of the basal and spinous cell layers behind the cut surface. These metabolic pathways are thus compatible with cell migration. Unsaturated hydrophobic lipids were restored in the superficial cell layers 120–240 h postoperatively, probably reflecting initial formation of keratohyalin granules. A sparse amount of glycogen was found only in the regenerating epithelium.
Degrees of saturation with respect to apatites in parotid saliva at various pH values
Authors: LARSEN M. JOOST
Published: October 2007

abstract— The purpose of the present work was to investigate the degrees of saturation with respect to hydroxyapatite and fluorapatite in saliva at various pH's. The data of ionic activities in parotid saliva were collected from the literature and the degrees of saturation with respect to hydroxyapatite and fluorapatite were calculated. It was found that parotid saliva was supersaturated with respect to both apatites above pH 5.5, unsaturated with respect to hydroxyapatite and concurrently supersaturated with respect to fluorapatite in the pH range 5.5–4.5, while it was unsaturated with respect to both apatites below pH 4.5. In the laboratory it has been found that when enamel is exposed to a liquid unsaturated with respect to hydroxyapatite and supersaturated with respect to fluorapatite, a caries‐like lesion is developed. A liquid unsaturated with respect to both apatites leads to an erosion‐like injury. It is concluded that the two chemical conditions leading to the two types of enamel lesions may both occur in the oral cavity.
Effect of Listerine® on dental plaque and gingivitis
Authors: FORNELL JAN , SUNDIN YVONNE , LINDHE JAN
Published: October 2007

abstract— The present study was performed in 10 adults in order to evaluate the effect of an antiseptic mouthrinse (Listerine®) on the rate of dental plaque formation and gingivitis development during a 2‐week period when all efforts towards active mechanical oral hygiene were withdrawn. The study was performed as a crossover study and was carried out during four consecutive 2‐week periods. During the first and third periods (preparatory periods) the participants were subjected to repeated professional tooth cleanings in order to establish plaque‐ and gingivitis‐free dentitions. During the second and fourth periods (test and control periods) the participants were not allowed to brush their teeth but rinsed their mouths three times a day with Listerine or a placebo mouthwash. Plaque Index, Gingival Index, gingival fluid flow, and crevicular leukocytes were assessed on d 0, 2, 4, 7, and 14. On d 7 and 14, dental plaque was removed from the right and left jaws respectively and the wet weights determined. The chemotactic activity elaborated by the plaques was studied in Boyden chambers. During the Listerine test period, significantly lower Plaque and Gingival Index values were scored and lower amounts of plaque could be sampled in comparison to the control period.
Contralateral symmetry of acid etched enamel surfaces
Authors: JÖRGENSEN KNUD DREYER
Published: October 2007

abstract— Scanning electron microscopy (SEM) of phosphoric acid etched labial enamel surfaces of human permanent incisors and canines showed that the etch pattern, including the depth of the etched relief, may vary significantly from tooth to tooth and between different areas of the same tooth. On the other hand, pairs of contralateral teeth showed a very similar etch pattern symmetrically along the midline. No difference in the pattern could be found in enamel etched with three different orthophosphoric acids: 50% with 7% ZnO, 37%, and 35%. Therefore, when comparing the depth of penetration of different coldcuring restorative resins, composite or non‐composite, into the etched enamel relief, it seems appropriate to study these materials two‐by‐two on pairs of contralateral teeth.
Adaptation of resinous restorative materials to acid etched enamel surfaces
Authors: JÖRGENSEN KNUD DREYER , SHIMOKOBE HIROKATA
Published: October 2007

abstract— The purpose of this paper was to study by means of scanning electron (SEM) and optical microscopy the adaptation of the low‐viscous non‐composite Nuva‐Seal(r) and of the three high‐viscous composite restorative materials Adaptic(r), Compocap(r) and Concise(r) to phosphoric acid etched enamel surfaces from symmetric areas of pairs of contralateral human permanent anterior teeth. The SEM study demonstrated that the two types of material equally well reproduce the details of the enamel surface; the light microscopic observations showed that the length and shape of resin tags in the enamel surface are independent of the materials examined. The observations seem to allow the conclusion that bonding of composite restorative resins to phosphoric acid etched enamel surfaces is not conditioned by the employment of an intermediate film of a low‐viscous non‐composite resin.
Calcium fluoride in demineralized bones from rats with experimental chronic fluorosis
Authors: LINDEMANN GERTRUD
Published: October 2007

abstract— Thirteen male rats, 7 or 10 months old, were given 0.05% NaF in the diet or 0.025% NaF in the drinking water for periods of 3 to 20 weeks. Femur/tibia bones were demineralized in 3.25% HNO3, the process being watched on radiographs. As soon as all radiopaque material representing mineralized bone had disappeared, demineralization was discontinued. In some instances the process was stopped while some radiopaque material was still present. Hematoxylin‐eosin stained paraffin sections from all bones showed deep blue granules, fluoride granules. Transmission electron microscopy and selected area diffraction revealed that the fluoride granules contain microcrystalline CaF2. X‐ray diffraction of hydrazine‐deproteinated, demineralized fluorotic bones revealed the presence of CaF2 and a minor unidentified component. The results are discussed in relation to (1) the identity of the fluoride granules, and (2) their inconsistent presence in demineralized hard tissues.
An immunofluorescence study on the cross‐reaction between Strep. 2A and human oral mucosa
Authors: DONATSKY O.
Published: October 2007

abstract— Immunologic cross‐reactions between Strep. 2A, fetal human oral mucosa (FHOM), and adult human oral mucosa (AHOM) were investigated by the use of a double layer immunofluorescence staining technique. Rabbit sera were prepared against Strep. 2A and FHOM. Seventeen sera from patients with recurrent aphthous stomatitis (RAS) and with known antibodies against Strep. 2A and AHOM were examined for antibodies against FHOM. The distribution of endpoint titers against FHOM in the sera from RAS differed significantly from the distribution in 17 controls. The immune absorptions in the rabbit sera and in the 17 sera from patients with RAS indicate that some cross‐reacting antigenic determinants are shared between Strep. 2A, FHOM, and AHOM. Further, the present results indicate that antibodies are produced against antigenic determinants which are not shared by Strep. 2A, FHOM, and AHOM. The role of cross‐reacting antigens in the pathogenesis of RAS is discussed but remains obscure.
Presence or absence of plaque on subgingival restorations
Authors: WAERHAUG JENS
Published: October 2007

abstract— One hundred and eight extracted teeth with restorations placed below the gingival margin were stained and examined under the stereomicroscope with the aim of scoring presence or absence of subgingival plaque. Individual observations showed that a subgingival restoration can be completely covered with plaque in as short a time as 6 weeks and it can be free of plaque for as long as 2 years. In the material as a whole about 9 out of 10 of the restorations were covered with plaque subgingivally. Since the material is selected, these proportions cannot be claimed to be valid for the population as a whole, but the observations suggest that plaque sooner or later will accumulate on most if not all subgingival restorations. Rough surfaces and or inadequate marginal adaptation are likely to facilitate a more rapid adherence of bacteria to the restorations than to the smooth tooth surface. It is concluded that restorations placed below the gingival margin indirectly are strongly involved in the etiology of destructive periodontal disease and the cause of many extractions.
Prolonged in vitro closure of the mouse secondary palate by salicylates
Authors: SAXEN IRMA
Published: October 2007

abstract— In organ culture sodium salicylate and acetylsalicylic acid in a 1.4 mM concentration caused prolongation of the time needed for the closure of the mouse secondary palate. The response of Strain A and the hybrids CBA×A was more distinct than that of Strain CBA. The mitotic rate, calculated from serial sections, was significantly reduced in the salicylate‐treated palatal shelves in both strains. The extrapolation of the results to an in vivo situation is discussed in the light of different theories of the mechanism of cleft palate formation.
Effect of oxytetracyclineand purified calcein (DCAF) on theapposition and mineralization of rat incisor dentin
Authors: RASMUSSEN PER
Published: October 2007

abstract— Thirty male rats in groups of ten were given intraperitoneal injections of oxytetracycline and purified calcein (DCAF) every day for 10 d in order to determine whether these fluorescent hard tissue markers per se had any adverse effects on weight development and dentin apposition and mineralization. It was found that oxytetracycline and DCAF in doses of 15 mg/kg, which are the routine doses used by the author in hard tissue studies, do not seem to have any measurable influence on these parameters, while their ability to cause fluorescence is fully satisfying in dentin as well as in bone.
Sealing properties of intermediary bases and effect on rat molar pulp
Authors: KARJALAINEN SÁRA , FORSTEN LENNART
Published: October 2007

abstract— Five “cream‐like” intermediary bases (Hypocal®, Dycal®, Reocap®, Cavitec® and Dropsin®) were studied using ZnO‐eugenol (ZOE) and phosphate cement for comparison. The in vitro experiments, which were designed to reveal the penetration of a dye and an etching liquid, showed that Dropsin and Hypocal were permeable to dye and that Dropsin was permeable to acid as well. The in vivo experiments revealed no definite differences between the different cream‐like base materials, nor were there differences between those and the conventional cements. The overall mildness of the dentin‐pulp reactions and the suitability of the rat molar for this kind of research are discussed.
Periodontal status of neighboring teeth after orthodontic closure of mandibular extraction sites
Authors: WISTH PER JOHAN
Published: October 2007

abstract— The gingival health, pocket depth and loss of fiber attachment of the mandibular first molars and first premolars were studied by clinical and radiographic methods after the embedded second premolar had been surgically removed on one side and extracted after eruption on the other, and the spaces had been closed orthodontically. Twenty‐nine children participated in the study. Their mean age at the time of tooth removal was 11 years 3 months. The mean duration of the treatment was 20 months, and the children were examined 1 1/2 to 2 years after removal of the bands. The gingival status was generally similar on both sides. Some constriction of the alveolar process was observed in more than half the cases, both after extraction and after surgical removal. The loss of attachment on the buccal and lingual surfaces was approximately the same in both groups, whereas the radiographic distance from the cementoenamel junction to the bone margin on the proximal surfaces adjacent to the removed tooth was somewhat greater after extraction than after surgical removal.
Creep of dental amalgam as a function of heat treatment
Authors: ESPEVIK S.
Published: October 2007

abstract— The creep of dental amalgam was measured as a function of heat treatment of the amalgam. The treatment significantly reduced the creep rate. The β1 (Ag‐Hg) phase was detected in the heat‐treated amalgam by X‐ray diffraction and metallographic methods, and it appeared that the reduction in creep rate was due to the γ1→β1 transformation.