bluuebunny/crossref_metadata_2025 huggingface dataset:
Bond strength of composites applied to acid‐etched enamel
Authors: RAADAL MAGNE
Published: October 2007

ABSTRACT – The adhesion to acid‐etched enamel of a four‐component composite, Concise® Enamel Bond System, was studied. The composite was applied undiluted over an intermediate resin layer and diluted with different amounts of resin. Corresponding surfaces of contralateral premolars were used to ensure that the composite samples were tested on areas with similar enamel etch patterns. Eighty specimens were tested. The results of this study indicated that the adherence of undiluted composite to etched enamel surfaces was not improved by using an intermediate layer of low‐viscous resin. Composite diluted with liquid resin had poorer adherence than undiluted composite. There was no difference in the results from two degrees of dilution.
Effect of thyroxine and growth hormone on dentin production in maxillary incisors in the rat
Authors: HANSSON LARS INGVAR , STENSTRöM ANDERS , THORNGREN KARL‐GÖRAN
Published: October 2007

ABSTRACT – Dentin production and longitudinal growth of maxillary incisors in female rats, age 60–95 d, were determined by the tetracycline technique in hypophysectomized rats after administration of growth hormone and thyroxine during age 75–95 d. Hypophysectomy was performed at age 60 d. Administration of thyroxine resulted in a considerable increase in dentin apposition and longitudinal growth of the tooth. The same effect, but somewhat lower, was registered for growth hormone. Growth hormone and thyroxine administered simultaneously had an additive synergistic effect. Compared with the effect of hypophysectomy and of hormone administration on longitudinal bone growth and cortical bone remodeling the effect on dentin production and longitudinal growth of the maxillary incisors in the same rats is less pronounced and shows a different pattern in reaction, indicating differences in sensitivity for different cell systems and difference in endocrine control.
Ultrastructure of salivary calculi
Authors: ANNEROTH G. , ENEROTH C.‐M. , ISACSSON G. , LUNDQUIST P.‐G.
Published: October 2007

ABSTRACT – Twenty‐one submandibular salivary calculi from 19 patients were examined with the light and electron microscope. Adjacent to the peripheral parts of the calculi metaplastic squamous epithelium or connective tissue was seen in close contact to the mineralized matrix. Disintegrated cellular substances from these tissue components were in some cases found to condense in a peripherally located zone of the salivary calculi. The morphology of the examined salivary calculi varied extensively not only within each calculus but also from one calculus to another. High and low incidence of crystals gave rise to the lamellated pattern. In some cases the crystals were so abundant as to give a dense homogeneous appearance. In the central parts of the calculi spheroid bodies of very low electron density with a size ranging from 1 to 100μm were found in an amorphous matrix. The origin of these structures is discussed. In the peripheral parts of some calculi os‐miophilic spherical bodies with an electron microscopical appearance similar to lipid granules as well as bacteria of cocci or coliform type were found. Degenerated bacteria might in some cases contribute in forming part of the peripheral organic matrix.
Assessment of age‐at‐death from mandibular molar attrition in medieval Danes
Authors: HELM SVEN , PRYDSÖ UWE
Published: October 2007

Abstract— Stages of occlusal attrition of the permanent mandibular molars were recorded in 235 Danish medieval skulls, 52 of which were in various states of mixed dentition. For the first and second molar, ages at emergence and ages at occurrence of the earlier stages of attrition were estimated from the mixed dentitions, on the assumptions 1) that the age at eruption of a given number of permanent teeth was similar in medieval and contemporary Danish children, and 2) that the rate of attrition was similar for the first and second molars. Estimation of ages at occurrence of the later attrition stages and of the age at third molar emergence was based on percentage frequency distributions of the stages of attrition using reiterative calculating procedures. Third molar emergence was estimated at the early age of 14 years. It is argued that assessments of age‐at death could be made fairly accurately for the age range 5–30 years, and with decreasing accuracy until about 40 years of age.
Determination of fluoride and chlorhexidine from chlorhexidine/fluoride‐containing dentifrices
Authors: DOLLES OVE K. , BONESVOLL PER , CAMST OLAV N. , GJERMO PER
Published: October 2007

Abstract— The intention of the present experiment was to study the effects of a possible interaction between fluoride and chlorhexidine when both agents were incorporated in the same vehicle. The amount of fluoride extractable from dentifrices containing 0.1% NaF and the fluoride ion activity were not reduced by the addition of 2% chlorhexidine digluconate. Less than 50% of the added chlorhexidine was available when the dentifrices were dissolved in deionized water. This was not affected by the presence of fluoride. The in vitro antibacterial activity of the chlorhexidine‐containing dentifrices was not reduced by the addition of fluoride. Approximately 40% of the chlorhexidine was retained in the human oral cavity after brushing for 1 min with both the chlorhexidine‐ and the chlorhexidine fluoride‐containing dentifrice. Thus the binding of chlorhexidine to vehicle ingredients when dissolved in water is probably too weak to affect the retention in the mouth.
Method for radiographic assessment of alveolar bone level at endosseous implants and abutment teeth
Authors: LARHEIM T. A. , WIE H. , TVEITO L. , EGGEN S.
Published: October 2007

Abstract— A radiographic method expressing the alveolar bone level in absolute figures is presented. By means of a calibrated measuring radiographic film fixed to a magnifying viewer, alveolar bone levels were determined directly on intraoral periodic “identical” radiographs. A polyether impression was made for fixation of the filmholder in order to obtain reproducible radiographs. The method was applied to assess changes in the alveolar bone level at endosseous implants and abutment teeth. Radiographs af 23 endosseous implants and 21 abutment teeth from nine patients were examined and measurements of the alveolar bone level were perfarmed. The mean difference between double observations on the same exposure as well as on repeated exposures was about 0.2 mm (s.d. 0,17–0.32 mm). The uncertainty of the present radiographic method was mainly due to the measurement procedure, as the radiographic technique showed a high degree of reproducibility. The method is a simple and reliable technique for longitudinal investigations of changes in the alveolar bone level at endasseous implant and tooth abutments.
Surface analysis of screwposts
Authors: ARVIDSON KRISTINA , WRÓBLEWSKI ROMUALD
Published: October 2007

Abstract— The content and distribution of metallic ions on the surface of gold‐plated brass screwposts (Dentatus and MecOdont) were analyzed by X‐ray microanalysis. On screwposts from one of the manufacturers the protective outer layer of gold was found to be localized to specific areas of the posts, i.e. the grooves, while unprotected Cu‐Zn alloy was found on the ridges. The results are discussed with regard to results on root posts published earlier. Screwposts constructed in this way would appear to be of doubtful clinical value.
Concentrations of Ca, Mg, Mn, Sr and Zn in supra‐ and subgingivalcalculus
Authors: KNUUTTILA M. , LAPPALAINEN R. , KONTTURI‐NÄRHI V.
Published: October 2007

Abstract— The concentrations of Ca, Mg, Mn, Sr and Zn in supra‐ and subgingival calculus collected from mandibular anterior teeth mainly of the same persons were analyzed with atomic absorption spectmphotometry. The results showed highly significantly (P<0.001) greater Zn and Sr concentrations in subgingival samples. The mean value of Zn was 5.4 times higher in subgingival calculus than in supragingival calculus. In contrast, the concentration of Mn was significantly (P<0. 01) higher in supragingival calculus. The difference in the concentration of Mg in supra‐ and subgingival calculus was highly significant (P<0. 001) only when samples from the same person were compared. The concentration of Ca was very similar in both types of calculus and individual variations were very small.
Effect of chlorhexidine on the relative proportions of Streptococcus mutans and Streptococcus sanguis in hamster plaque
Authors: EMILSON C. G. , WESTERGREN G.
Published: October 2007

abstract— The effect of chlorhexidine on the proportions of Streptococcus mutans and Streptococcus sanguis in plaque was studied in hamsters fed a diet containing 28% sucrose. In animals given chlorhexidine in their drinking water for 10 d a decrease in the population of S. mutans and an increase of S. sanguis occurred in the plaque. Following the removal of chlorhexidine the population of S. mutans increased again in the presence of sucrose and the number of S. sanguis returned to initial values. When animals were given a sucrose‐free diet the low proportion of S. mutans observed following the short‐term chlorhexidine period persisted. These data indicate that there is an inverse relationship between the number of S. sanguis and S. mutans in plaque and that the sensitivity in vivo of S. mutans to chlorhexidine can be used to suppress the population of S. mutans with a concomitant rise in the proportion of S. sanguis.
Effect of chlorhexidine on acidogenicity of dental plaque in vivo
Authors: OPPERMANN RUI V.
Published: October 2007

Abstract— In order to evaluate the effect of chlorhexidine on the acidogenicity of dental plaque, pH changes in plaque were measured in situ after sucrose applications. The results showed that a 0.2% chlorhexidine mouthrinse inhibited acid production for a period of 24 h, whereas a 0.05% chlorhexidine rinse showed an inhibitory effect for 4 h. It is suggested that the mechanism involved may be related to the retention of chlorhexidine in the mouth and in plaque providing a bacteriostatic milieu which may be of importance in the observed long‐term effect.
Monkey pulpal response to composite resin restorations in cavities treated with various cleansing agents
Authors: ERIKSEN HARALD M. , LEIDAL TORGER INGAR
Published: October 2007

Abstract— Pulpal response to composite resin restorations placed in experimentally prepared cavities treated with various cavity cleansing and etching agents were studied in monkey teeth. The use of etching agents and cleansers with a demineralizing potential enhanced the pulpal response to composite resin restorations. Bacterial proliferation on the cavity walls around the composite restorations may be one of several factors causing the harmful pulpal responses found. The protective effect of a calcium hydroxide‐containing cavity lining material was confirmed.
Possible origin of sulfated glycosaminoglycans in human dental calculus
Authors: EMBERY GRAHAM , NORDBÖ HÄKON
Published: October 2007

Abstract— The sulfated glycosaminoglycans present in human dental calculus have been shown to be dermatan sulfate and chondroitin‐4‐sulfate. The composition suggests that the glycosaminoglycans present in calculus, particularly subgingival material, could originate as a result of associated periodontal disease since closely similar compounds have previously been identified in normal and inflamed human gingiva.
Retention of fissure sealant in primary second molars after 6 months
Authors: POULSEN S. , PELTONIEMI ARJA‐LIISA
Published: October 2007

Abstract— Low retention of fissure sealant in primary teeth could be due to insufficient moisture‐control in young children. In the present study 10 primary maxillary second molars and 29 primary mandibular molars were sealed using rubber darn while their contralateral teeth were sealed using cotton rolls. No difference in the retention of the sealant could be demonstrated.
Short‐term reactions of human dental pulp to formocresol and its components – a clinical‐experimental study
Authors: MEJàRE INGEGERD , LARSSON ÅKE
Published: October 2007

Abstract – Pulps of 58 human premolars were amputated under standardized conditions, and standardized amounts of dressings containing 4 or 19% formaldehyde solutions, 35% cresol or formocresol, were applied to the wound surface. Tissue reactions were studied after 4, 8 or 16 d using enzyme histochermical and routine histologic techniques. The results showed that formaldehyde fixed the tissue in vivo, the extent of fixation being dependent on the concentration of formaldehyde. Fixation did not reach the apical foramen. Formaldehyde also caused vascular changes at varying distances from the fixed tissue, indicating transport of formaldehyde via the vessels, Cresol caused necrosis and vascular changes limited mainly to the upper portion of the root pulp. Application of formocresol resulted in devitalization of the whole or almost the whole of the root pulp within 4 d, accompanied by complex vascular changes, depending mainly on the formaldehyde component. Root pulp exposed to formocresol for 5 min only showed partial devitalization due to compromised blood flow, while practically no fixation occurred. The inflammatory response to formocresol and its components was remarkably limited.
Comparative bone morphometric analysis of mandibles and iliac crests
Authors: VON WOWERN NINA , MELSEN FLEMMING
Published: October 2007

Abstract – A comparative analysis of bone mass in the mandible and the iliac crest has been carried out in autopsy specimens from 30 subjects aged 23–84 years. Microradiograms of standardized 100‐μm‐thick sections of the undemineralized plastic embedded material from the two locations were used for quantitation. The following measurements were carried out by electronic point‐counting: 1) the percentage of cortical bone mass in the subperiosteal and subendosteal layers, 2) mean cortical width, and 3) the percentage of trabecular bone mass in die iliac crest. Positive correlations were found in the expressions of bone mass within the mandible; the values were significantly higher in the 200‐μm‐thick subperiosteal layer than in the remaining part of the mandibular cortex. Only a poor or no correlation was found in the expressions of bone mass from the two sites. The investigation, therefore, shows that bone mass and cortical width in the mandible cannot be predicted from a biopsy from the iliac crest. This finding may partly be due to different age‐dependent functional changes of the two bones.
Elements in minor or trace quantities in zinc phosphate cements
Authors: BRUNE DAG
Published: October 2007

Abstract – Eight powders and two liquids of zinc phosphate cements have been analyzed by optical emission spectrography for the purpose of characterizing elements in minor or trace quantities. The following elements were measured: bismuth, boron, cadmium, chromium, copper, iron, lead, silver and titanium. The content of any of these elements did not exceed the level of 0.1%. The amounts of such elements which might be transferred to the gastrointestinal tract associated with dissolution from unsuccessful restorations have been considered.
Dentin formation in formocresol pulpotomized primary monkey teeth studied by tetracycline and 3H‐proline incorporation
Authors: RØLLING INGE , MELSEN BIRTE
Published: October 2007

Abstract – The influence of formocresol treatment on the pulp tissue of 24 primary monkey teeth was studied using tetracycline and 3H‐proline labeling techniques. Six untreated monkey teeth served as controls. The tetracycline labeled teeth were examined between 352 and 600 d, following treatment. The 3H‐proline labeled teeth were observed over a period of 22–607 d, the isotope being administered 15 d before extraction. The labeling was evaluated in the coronal, middle and apical area of the roots. Dentin formation as indicated by tetracycline labeling was observed in both control teeth and successfully treated teeth, as well as in some of the unsuccessfully treated teeth. The average dentin formation rate per day varied from 1 μm in the control teeth to 0.14 μm in the pulpotomized teeth (P<0.01). Success of treatment was of significant importance for the amount of dentin formation (P<0.001). Labeling with 3H‐proline, indicating collagen synthesis, could be observed in the pulp and predentin of the majority of areas judged to be normal, degenerated or inflamed. Labeling was not observed in fixed or necrotic tissue. In degenerated pulp tissue the proline labeling was clearly reduced. The findings indicate that dentin formation and collagen synthesis may take place in formaldehyde influenced pulp tissue although at a decreased rate.
Aberrant blastogenic response to LPS in experimental gingivitis of elderly subjects
Authors: HOLM‐PEDERSEN P. , GAUMER H. R. , FOLKE L. E. A.
Published: October 2007

Abstract – The blastogenic response of peripheral blood leukocytes to lipopolysaccharide (LPS), phytohemagglutinin (PHA) and LPS/PHA mixtures was followed over a short course of experimental gingivitis in elderly subjects (65–81 years) who strictly avoided oral hygiene procedures for periods up to 9 d. The leukocytes responded poorly to LPS, PHA and to LPS/PHA combinations. The concomitant heightened sensitivity of the gingiva to dental plaque among the elderly subjects may relate to the altered leukocyte response in this age group.
Clinical quality of amalgam restorations
Authors: SKOGEDAL OLE , HELöE LEIF ARNE
Published: October 2007

Abstract – The clinical quality of 203 mesio‐occlusal Class II and 127 buccal Class V restorations of 246 persons aged 25 years were studied. One third of the amalgam restorations were considered to be unacceptable. Marginal overhang was the prevailing type of failure (17%), recurrent caries occurred at 12% of the restorations, unacceptable proximal contact at 10%, unacceptable marginal adaptation at 8% and isthmus fractures at 2%.
Microleakage along composite restorations in human premolars after treatment with different cleansing agents
Authors: LEIDAL TORGER INGAR , ERIKSEN HARALD MARTIN
Published: October 2007

Abstract – Cavities prepared on extracted human premolars were treated with different cleansing agents and by different procedures. The cavities were filled with a composite restorative material and microleakage was assessed by recording the penetration of basic fuchsin dye. Only acid agents which removed the smeared layer, producing an etch pattern on the enamel cavity walls, were able to prevent microleakage.
Characteristics of growing bone surfaces
Authors: VILMANN H.
Published: October 2007

Abstract – Both bone‐forming and bone‐destructing cells may appear in different forms. This conclusion has been drawn as a result of compared observations from histomorphologic, histochemical and vital staining studies. The bone‐forming cells may be cuboidal and situated in one or more rows along the bone surfaces, or may be flat. The type of cell reflects the rate of bone formation. The bone‐resorbing cells may be big multi‐nucleated cells or small mononucleated cells. The latter cell type is well‐known from the literature although not referred to in textbooks of histology. Flat bone‐forming cells and small mononucleated bone‐resorbing cells resemble each other in the light microscope. Studies of bone growth with the aid of histomorphologic descriptions of cell types have to take this fact into account. Otherwise, erroneous conclusions may easily be drawn.
Biological evaluation of root canal antiseptics using in vitro and in vivo methods
Authors: WENNBERG ALF
Published: October 2007

Abstract – Five antiseptics commonly used in endodontic treatment were evaluated with regard to cytotoxicity and initial tissue irritating effect. The cytotoxicity was evaluated in a cell culture system using HeLa cells and the initial tissue irritating effect was assessed by application of the antiseptics onto an intact nonepithelialized tissue surface. The cell response was assessed by registering changes in the DNA synthesis of the cells and the tissue response was assessed by registering changes in the oxidoreductase enzyme activity of the tissue. To evaluate the ability of the cells and the tissue to overcome an induced damage, one part of the study included a recovery period before the condition of the cells and the tissue was assessed. The most severe cell and tissue reactions were caused by 5% Chloramine‐T® whereas no differences in toxicity or tissue irritating effect were found between 0.04% Jodopax®, 0.1% Bioscpt®, 0.1 % Hibitanc®, or 0.5% sodium hypochlorite. The HeLa cells showed the best recovery after having been influenced by Jodopax, Chloramine‐T or sodium hypochlorite solutions, whereas the best tissue recovery was observed in the experiments with Biosept and Hibitane.
Pain, tenderness and strength of human mandibular elevators
Authors: SHEIKHOLESLAM AKBAR , MØLLER EIGILD , LOUS INGER
Published: October 2007

Abstract – In terms of the mean voltage during maximal bite in the intercuspal position we compared the strength of the temporal and masseter muscles of 39 patients with functional disorders of the chewing apparatus and 45 controls. Maximal electrical activity was significantly stronger in the controls than in the patients. Differences between the two samples with respect to sex, age, number of opposing teeth in contact and the presence of pain and tenderness tended to favor stronger activity in the controls. However, the different levels of electrical activity, especially in the case of the masscter muscles, could only be accounted for on the basis of a difference in maximal strength. we suggest that the weaker elevator muscles of the patients was a predisposing factor making these muscles less fit to endure hyperactivity induced psychologically or as a reflex response to occlusal interferences and functional disorders of the temporomandibular joints or other elements of the oral neuromuscular system. The sample of controls had much stranger elevators, less susceptible to such hyperactivity.
Streptococcus mutans in plaque after mouth‐rinsing with buffers of varying pH value
Authors: SVANBERG MONA
Published: October 2007

Abstract – After a period of mouthrinsing with a phosphoric buffer solution with low pH the proportional distribution of Streptococcus mutans in plaque from occlusal retention sites was significantly higher than after a control period. This indicates that colonization with S. mutans may be favored or that other microorganisms competing with S. mutans are inhibited under these circumstances.
Autoradiographic investigation of proliferative responses in rat incisor pulp after vincristine administration
Authors: STENE TORBJØRN , KOPPANG HANNA STRØMME
Published: October 2007

Abstract –

0.7 mg/kg VCR was given to nine rats in three experimental groups. Twenty‐three hours after VCR injection the animals were injected with 3H‐thymidine. The animals were sacrificed 24, 48 and 72 h after the VCR injection, and by comparison with nine control animals similarly injected with sodium chloride solution and nucleotide, it was shown that VCR causes a delayed migration of pulp cells from the proliferative pool and a small but distinct inhibition of the incisal growth of the incisors. The growth inhibition corresponded to the normal growth over a 24‐h period in nou‐VCR‐injected animals.
Autoradiographic investigation of dentin production in rat incisors after vincristine administration
Authors: STENE TORBJØRN , KOPPANG HANNA STRØMME
Published: October 2007

Abstract –

0.7 mg/kg VCR was administered intravenously to nine rats in three experimental groups. One hour after VCR injection the animals were injected with 3H‐proline. The animals were sacrificed 1.5, 5 and 24 h after the VCR administration, and by comparison with nine control animals similarly injected with sodium chloride solution and 3H‐proline, it was shown that VCR causes an early, intracellular retention of labeled proline in the odontoblasts, an abnormal intracellular distribution of labeled material and a generally decreased secretion of dentinal matrix from the odontoblasts in the maxillary incisors. The severity of the effects were shown to vary in different parts of the incisors.
Neutrophil chemotaxis induced by anaerobic bacteria isolated from necrotic dental pulps
Authors: SUNDQVIST GÖRAN , JOHANSSON EVA
Published: October 2007

Abstract –

Anaerobic bacteria belonging to the species Bacteroides melaninogenicus, Bacteroides asaccharolyticus, Fusobacterium nucleatum, Peptostreptococcus anaerobius and Eubacterium alactolyticurn, isolated from necrotic dental pulps, were tested for their capacity to induce neutrophil leukocyte chemotaxis. Generation of chemotactic factors in serum by whole bacterial cells and chemotaxis induced by bacterial extracts were studied in vitro by the Boyden technique. Subcutaneously implanted wound chambers in guinea pigs were used for testing leukocyte migration in vivo. All bacterial strains had a similar high capacity to induce neutrophil chemotaxis. The heavy accumulation of polymorphonuclear neutrophil leukocytes associated with clinical and experimental infections by B. melaninogenicus or B. asaccharolyticus cannot be ascribed to any extreme ability of these organisms to generate chemotactic factors.
Bone tissue formation within a sintered microporous glass‐fiber network implanted in extraction sockets in the rat
Authors: EHRNFORD LARS , SUNDSTRÖM BENGT , WALLENIUS KJELL
Published: October 2007

Abstract –

Implants were prepared by sintering glass‐fibers into a three‐dimensional network with meshes smaller than 20 μm. Oblong 5x2x0.15 mm sheets of the test material were implanted in maxillary incisor alveoli in eight white rats. The alveoli were closed with a suture in the overlying mucosa. After 3 months the animals were sacrificed and sections from the site of implantation prepared. In three animals only root remnants were found but in the remaining five the implants were wholly or partially embedded in bone tissue. Sections studied with transmitted light, microradiography, and scanning electron microscopy showed that mineralized tissue had also formed within the pores of the network. The intimate contact between the individual fibers and the bone within the network was corroborated through microchemical analysis (EDX).
Pattern of age related bone loss in mandibles
Authors: VON WOWERN NINA , STOLTZE KAJ
Published: October 2007

Abstract –

A study was carried out to analyze the pattern of the age related bone loss in the mandibular cortex and to establish normal values and the observed range of morphometric variables on microradiograms of bone sections taken from a well defined site anterior to and below the mental foramen. Specimens were obtained from 100 Danish subjects with no known systemic bone disease or severe mandibular atrophy. Microradiograms of 100‐μm‐thin undemineralized vertical ground cross‐sections were produced. An electronic point‐counting system was used for the determination of 1) percentage bone mass, 2) mean cortical width (MCW), and 3) the percentage of Haversian canals with resorption surfaces. The analysis showed that cortical porosity and the percentage of Haversian canals showing resorption are unrelated to sex and increased after the age of 50. MCW and absolute bone mass (MCW ×% bone mass) are greater in males than in females and show a parallel age related decrease after the age of 50. Furthermore, the age related increase in cortical thinning and porosity is dependent on the individual as well as on age. Marked individual variation confined the use of these parameters to group analysis.
Strength properties of some gypsum‐bonded casting investments
Authors: FINGER WERNER , JØRGENSEN KNUD DREYER , ONO TAKASHI
Published: October 2007

Abstract –

The present investigations show that there is no correlation between on the one hand the wet and the dry compressive strength of the three gypsum‐bonded investments studied and on the other the compressive strength of the investments at burn‐out temperature. The study also demonstrated that there is no correlation between the compressive strength and the fracture resistance of sharp edges of the investment mold when exposed to the impact of the casting alloy entering the mold. The inconveniences caused by the fracture of such edges are prevented by a moderate rounding of the corresponding parts in the preparation.
A 3‐month study in monkeys of occlusal dysfunction and stress
Authors: BUDTZ‐JØRGENSEN EJVIND
Published: October 2007

Abstract –

A dysfunctional occlusal relationship was produced in six Macaca irus monkeys by insertion of occlusal splints in the maxilla which raised the vertical dimension of occlusion by 3–4 mm and incorporated interferences into the occlusion (test side). Gortisol levels of plasma and urine were measured by competitive protein binding analysis. At week 1 and week 3 after insertion of the splints there was a significant increase of 24 h urinary cortisol excretion rate and plasma cortisol concentration, indicating emotional stress. Furthermore, there was evidence of acute trauma from occlusion of the mandibular teeth of the test side, including a significant increase of tooth mobility and GI; radiographically there were signs of breakdown of marginal and interradicular alveolar bone. One animal developed periodontat pockets of 4–5 mm adjacent to the teeth of the test side. At week 6 and week 12 urinary and plasma cortisol levels had declined to basal values whereas tooth mobility, GI and PI remained elevated. There was no clinical or radiographic evidence of further loss of bone or increase of pocket depth adjacent to the teeth of the test side during the latter part of the experimental period. The results suggest that emotional stress may be involved in periodontal reactions associated with acute trauma from occlusion.
Morphology of a simple amelobloblastoma related to the human enamel organ
Authors: MATTHIESSEN MARTIN EBBE , VEDTOFTE POUL , RØMERT PAUL
Published: October 2007

Abstract –

The ultrastructure of a simple ameloblastoma was investigated. The epithelial cells of the tumor could be divided into peripheral cells of varying height, and dark and light central cells. The morphology was correlated to that of the human enamel organ. The low peripheral cells were very similar to the external enamel epithelium cells. The central cells had a certain resemblance to the stellate reticulum and stratum intermedium cells. The high peripheral cells had no counterparts in the enamel organ. Unlike the enamel organ the ameloblastoma showed extremely few and small gap junctions.
In vitro development of chlorhexidine resistance in Streptococcus sanguis and its transmissibility by genetic transformation
Authors: WESTERGREN GUDRUN , EMILSON CLAES‐GÖRAN
Published: October 2007

Abstract –

Three chlorhexidine‐sensitive strains of Streptococcus sanguis developed resistance to chlorhexidine when grown as continuous cultures in a fermenter containing medium with increasing concentrations of the drug. The MIC of the test strains increased by between two and three dilution steps and these high values were maintained after daily transfer in drug‐free medium for at least 15 d. In addition, the resistance of one of the strains persisted for more than 1 month of continuous growth in drug‐free medium in the fermenter. DNA from the resistant (Chx1) variants of the three strains transformed competent sensitive S. sanguis to increased chlorhexidine resistance, thus proving that resistance to this drug is an inheritable trait. Immunoelectrophoretic experiments showed that certain changes in the antigenic pattern of the Chx1 variants had occurred as compared with their sensitive wild‐type strains. Antigen extracts of the Chx1 variants and all Chx1 recombinants tested contained consistently less protein than those of the sensitive wild‐types.
Correlation between marginal adaptation of composite resin restorations and bacterial growth in cavities
Authors: QVIST VIBEKE
Published: October 2007

Abstract –

The purpose of the present study was to correlate the marginal adaptation of composite fillings to the bacterial growth in the cavities. Forty‐three cavities prepared in vivo on human third molars were acid etched and filled with the composite resin Concise®. After 4 months the teeth were extracted and examined for marginal leakage along the restorations. After histologic preparation an average of 38 sections from each cavity were stained and investigated for bacteria on the cavity walls and in the exposed dentinal tubules. General marginal leakage was found in 14 of the restorations and bacterial growth in 12. For 35 of the 43 restorations there was an agreement between marginal leakage and bacterial growth (P= 0.0002). Based on the results it is concluded that bacteria in a cavity can be used as an indicator of marginal leakage along the restoration.
Origin of salivary hepatitis B surface antigen
Authors: HURLEN BJØRN
Published: October 2007

Abstract –

Low titers of hepatitis B surface antigen (HBsAg) is often found in mixed saliva of antigenemic individuals. In the present study the occurrence of antigen in saliva was correlated to the content of albumin, which is not synthesized by the salivary glands, but represents a leakage into the oral cavity due to hemorrhage, exudation or transudation. The presence of antigen in saliva was also correlated to the titer of antigen in serum.
Ultrastructure of squamous epithelium during wound healing in palatal mucosa of guinea pigs
Authors: ANDERSEN LIS
Published: October 2007

Abstract –

The ultrastructure of the epithelium of wounded guinea pig palate was studied. Twenty‐four biopsies (animals) were used. Biopsies were taken 18, 48, 96, and 120 h after wounding. Essential changes in epithelial cell structure in response to wounding were as follows: microfilaments, suggested to represent actin‐containing filaments, became evident in the cortical cytoplasmic zone. Micro tubules prevailed in the peripheral cytoplasm. Tonofilament bundles assumed the character of short tufts or delicate bundles and. the amount of non‐bundled tonofilaments was increased. These observations suggest changes in the cytoskeletal/contractile system facilitating cell motility. The structure of lysosomal profiles indicates an enhanced phagocytic capability. Influence of fixation on preservation of non‐membrane‐bound organelles is suggested based on comparable morphometric data.
Distribution and forms of iodine in human oral cavity
Authors: TENOVUO JORMA , SÖDERLING EVA , ANTTONEN TYTI
Published: October 2007

Abstract –

Neither iodinated proteins nor iodinated. low‐molecular weight compounds (e.g. iodinated tyrosine derivatives) could be detected in concentrated human salivary supernatant by using the Ce(SO4)2‐method either directly or after thin‐layer chromatography. Salivary sediment contained free 1− ions, loosely bound iodine (released with saline) and strongly bound iodine (released with sonication, detergent and acid hydrolysis). A positive correlation between salivary and crevicuiar excretion of l− from plasma was observed. Thiocyanate ions, which competitively inhibit peroxidase‐catalysed oxidation and iodination reactions and which are abundant in human saliva, possibly prevent the coupling of l− to protein in vivo although some human salivary proteins are very susceptible to iodination in vitro.
Viability of human periodontal ligament cells after storage in milk or saliva
Authors: BLOMLÖF LEIF , OTTESKOG PER
Published: October 2007

Abstract –

The prognosis of replantation of traumatically exarticulated teeth is very much influenced by the conditions under which the teeth have been kept before replantation. Saliva has been recommended as the most suitable storage medium but there are no studies where saliva has been compared with other possible storage media. Milk is such an easily available storage medium. The purpose of the present investigation was to compare the storage effect of milk with that of saliva on human periodontal ligament cells. Milk was superior to saliva as storage medium with respect to number of viable cells, cell size, ability to recover and to heal experimentally produced wounds. The osmolality of milk seems to be the most important factor.
Vitality of periodontal ligament cells after storage of monkey teeth in milk or saliva
Authors: BLOMLÖF LEIF , LINDSKOG SVEN , HEDSTRÖM KARL‐GÕRAN , HAMMARSTRÖM LARS
Published: October 2007

Abstract –

Vitality of die periodontal ligament (PDL) is necessary for a successful healing after replantation of exarticulated teeth. In the present investigation newly extracted teeth from monkeys were stored in saline, milk or saliva for 1–3 h. Freeze sections were made and the vitality of the PDL was determined histochemically. Milk seemed to provide better storage conditions than saliva or saline.
Effect of thickness of peridental restorations on the casting precision
Authors: FINGER WERNER
Published: October 2007

Abstract –

The present study has shown that the precision of peridental gold alloy castings depends both on the specific properties of the investment used and on the thickness of the pattern. In all cases the inside diameter of the castings decreased with increasing thickness. The most accurate results were obtained with an experimental investment characterized by a setting expansion of 0.05%, a thermal expansion high enough to compensate for the alloy contraction during cooling from solidus to room temperature, and a compressive strength of only 27 kg/cm2 at 67O° C.
The Development of ethics in dentistry
Authors: AHLBERG JAN ERIK
Published: October 2007

At the Annul Meeting of the Scandinavian Division (N.O.F.) of the International Assocation of Dental Research in Helsingfors 15‐16 August 1980 a symposium was held on ethical problems dentistry. The four papers presented at the symposium are publies in the following pages.
Nature and frequency of dental changes in idiopathic hypoparathyroidism and pseudohypoparathyroidism
Authors: BÖRGLUM JENSEN STEEN , ILLUM FRANDS , DUPONT ERIK
Published: October 2007

Abstract— Elven patients with idiopathic hypoparathyroidism and pseudohypoparathyroidism were examined orally and medically. All patients had a history of tetanic and or epileptic manifestations. Correspondingly, disturbances in the metabolism of calcium and phosphorus had been present in all. Dental anomalies were demonstrated in all patients but one. Enamel hypoplasia wasw observed in six cases, distrubances in tooth eruption in eight, root defects in five and hypodontia in seven. Dental anomalies were more frequent than could be expected from the literature, probably because the dental aspects of hypoparathyroid discase often have been overlooked. In the present material, the above‐mentioned disturbances were most severe and frequent in the pseudohypoparathyroid group. Hypoparathyroid conditions are highly invalidating, easily accessible to treatment, but often undiagnosed for years. Therefore, the dental observation of severe disturbances in tooth formation and eruption pattern may be of crucial importance and shold lead to further medical investigation.
Cytotoxicity of some solutions used for root canal treatment assessed with unman fibroblasts and lymphoblasts
Authors: KOSKENEN KARI P. , RAHKAMO AULI , TUOMPO HELENA
Published: October 2007

Abstract— The cytotoxicity of seven solutions used in root canal therapy was tested in human fibroblast and lymphoblast cultures. The amount of cell damage was assessed by measuring the release of 51Cr form labeled cells into the medium. The solutions, When applied at therapeutic concentrations, displayed high toxicity in vitro and difference in cytotoxicity were seen between different solutions. Generally, lymphoblasts were found to be more sensitive than fibroblasts. The cytotoxic profiles of the two cell types resembled each other except when 5% sodium bypochlorite or 0.2% Hibitance was used. When the criterion of total cell lysis was 50%51Cr release, The toxic concentrations of the solutions tested ranged between 1:25 and 1:900 (v/v) for fibroblasts. For lymphoblasts the corresponding concentration range was between 1:40 and 1:750. Despite technical simplicity and good reproducibility the 51Cr release method proved unreliable for testing the cytotoxicity of endodontic solutions. Because the methodological errors cannot be foreseen the 51Cr release method requires supproting evidence form other methods.
Stoichiometric and X‐ray diffraction analysis on the γ2→η′ transformation in a dispresant phase silver amalgam
Authors: JENSEN STIG JORGO , JÖRGENSEN KUND DREYER
Published: October 2007

Abstract— Phase composition of an amalgam prepared from a two‐particle alloy was determined over a 2‐year period by X‐ray diffraction. The γ2content decreased from 3.6% to 0.3%, and η′ increased from 3.9% to 10/0%. These alterations in ph content agreed with stoichiometric calculations performed on the basis of the solid state reaction: γ2+Ag/Cu→η′+γ1
Histomorphmetric analysis of primary teeth during the process of resorption and shedding
Authors: RÖLLING INGE
Published: October 2007

Abstract – The state of pulp tissue and periodontal root surface of 90 non‐carious human primary teeth during the process of resorption and shedding was assessed by histomorphometric means. The teeth were classified into preshedding, shedding and delayed‐shedding groups according to age of the child at the time of extraction. The root surface length measured from the cementoenamel junction was related to stages of shedding. Inflammatory cells in the pulp tissue were observed in all three group (P 0.05). Odontoclasts in the pulp tissue could be demonstrated in the shedding and delayed‐shedding stages (P<0.05). Polymorphonuclear leukocytes and odontoclasts were not observed before resorption had occurred approximately 1 mm subjacent to te cementoenamel junction. Active rescrption of te periodontal root surface was observed in all stages. Deposition of cementum‐like tissue in resorption lacunae on the root surface was most pronounced in the delayed‐shedding stage showing repair 30% of resorbing root surface length. The findings idicate that the process of resorption occurs mainly during the shedding stage and repair tends to accelerate in the delayed‐shedding stage. The predentin appears to have more power of resistance than any other part of the tooth and there is no reason to believe that the pulp participates in the process of resorption of human primary teeth under physiologic conditions.
A 2‐year report on caries prevention by fluoride varnishes in a community with fluoridated water
Authors: SEPPÄ LISA , TUUTTI HEIKKI , LUOMA HEIKKI
Published: October 2007

Abstract – The benefit of semi‐annual applications of sodium fluoride varnish (Duraphat®) and silanc fluoride varnish (Fluor Protector®) was studied in 11‐13‐year‐old children with life‐long exposure to fluoridated drinking water (1–1.2 parts/ 106). Annual clinical and radiograpic examinations were made on 67 children in the Duraphat group and 71 children in the Fluor Protcctor group. Floride varnish was applied semi‐annually using the half‐mouth tecnique. At the end of 2 years, the mean overall DMFS‐ increments on te control side and test side of the Duraphat group were 5.0 and 3.8 (P 0.01), respectively, and of te Fluor Protector group 3.7 and 3.3 (NS). The caries redutions were 24%and 12%, respectively. Since there were no differences between initial mean DMFS scores of te groups, it was assumed that lower increments in the Fluor Protector group were due to fluoride ions crossing the midline and providing protectioon on the control side as well. When increments in the Duraphat control side and the Fluor Protector test side were compared, the caries reducation of Fluor Protector was 35% (P<0.01). Fluoride varnishes provide additional benefit even when fluoride intake from drinking water is optimal.
Periodontal status of 14–16‐year‐old Danish schoolchildren
Authors: HOOVER JEYARAJ NESAKUMAR , ELLEGAARD BIRGIT , ATTSTRÖM ROLF
Published: October 2007

Abstract – The purpose of this study was to determine the prevalence of periodontal disease in teenagers. The survey was conducted on 325 children aged 14,15 and 16 years, living in Aarhus, Denmark. Pocket depth and loss of attachment were measured in mm at the maxillary and mandibular first molars and incisors. Plaque, calculus and gingival bleeding on probing were recorded. A total of 221 children (68%) had 4–5 mm deep pockets and 19 children (5.8%) had pockets deeper than 5 mm on at least one tooth Approximately 11% of the subjects showed loss of attachment on at least on tooth. The frequency of surfaces with plaque and gingivitis was high in all three age groups. Plaque, gingivitis, deepened pockets and loss of attachment were most frequently observed on interproximal surfaces. No significant differences were observed between the sexes with regard to periodontal disease.
Uncoated specimen of human enamel obeerved in the scanning electron microscope
Authors: RISNES S. , STÖLEN S. Ö
Published: October 2007

Abstract – A1‐mm‐thick section of human premolar was acid etched and observed uncoated in the SEM at accelerating voltages of 3, 5, 10 and 15 kv. Prisms and interprismatic substance were easily distinguishable. Low‐voltage operation (3 and 5 kv) gave the best results. Specimen charging was detectable at 5 kv and caused reduced image quality at 10 and 15 kv. Application of silver paste did not reduce charging appreciably. Prolonged observation at high magnification (x 10 000) resulted in contamination of the specimen with consequent charging and reduced resolution. Dental enamel seems to be a material which is well suited when uncoated for obervation in the SEM. This may be due both to the high content of the relatively heavy atom calcium, giving good secondary electron emission, and possibly to a certain degree of conductivity caused by diffusible icons.
Short‐term investigation on the influence of cigarette smoking upon plaque accumulation
Authors: BERGSTRÖM JAN
Published: October 2007

Abstract – The influence of cigarette smoking on plaque accumulation ws studied in young adult males who endeavoured to stop smoking. Plaque accumultion was evaluated photogrammetrically during a 5‐d smoking period and, after in interval of at least 30d, during a non‐smoking period of the same length. It was found that the amount of plaque was comparatively larger and plaque accumulation rate consequently increased in smokers throughout the smoking period. The differeces were small, however, and not statistically significant. The result: substantiates the view that cigarette smoking has no antibacterial potency so as to reduce plaque formation on tooth surfaces.
Effect or aqueous solutions of sorbitol‐xylitol on plaque metabilism and on growth of Streptococcus mutans
Authors: RÖLLA G. , OPPERMANN R. V. , WAALER S. M. , ASSEV S.
Published: October 2007

Abstract – The present study showed that the growth of Streptococcus mutans GS5 was inhibited by xylitol, and this indicates together with previous reports that this is a common phenomenon in this species. Sorbitol was found to increase the growth of S. mutans strains OMZ 176 and GS5 slightly compared with cultures with no external carbon source. Additional of small amounts of xylitol to the sorbitol cultures give a growth below that of cultures with no extra carbon. Dental plaque chalenged with sorbitol gave a small pH drop whereas xylitol caused a negligible decrease in pH. Sorbitol‐xylitol challenges gave less acid production than sorbitol challenges alone.