bluuebunny/crossref_metadata_2025 huggingface dataset:
Combined Effects of Sucrose and Fluoride on Experimental Caries and on the Associated Microbial Plaque
Authors: Ostrom Carl A. , Koulourides Theodore , Hickman Frances , Phantumvanit Prathip
Published: November 2010

In an experimental model, slabs of sound and presoftened bovine enamel were worn in the human mouth for seven days except for periodic removal for in vitro exposure to experimental variables. Supplementation with 3% sucrose for 10 minutes, four times daily for seven days yielded predicted levels of experimental caries. Parallel exposure to 3% sucrose containing 100 ppm fluoride sharply reduced or negated the resultant caries in originally sound enamel, and reversed the simulated pre-experimental caries in most samples of presoftened enamel. Serial layers of test enamel surfaces showed high levels of fluoride accumulated in the originally sound enamel, and even higher levels in the presoftened enamel that had been supplemented with sucrose-fluoride solution. Quantitation of the plaque microbial flora showed that the fluoride ion exerted no detectable influence. Consistent with the findings in previous studies, some correlation appeared to exist between the degree of experimental caries and that proportion of total plaque that was comprised of S salivarius, S mutans, or lactobacilli.
Electromyographic Silent Periods and Jaw Motion Parameters: Quantitative Measures of Temporomandibular Joint Dysfunction
Authors: Bailey J.O. , McCall W.D. , Ash M.M.
Published: November 2010

The purpose of this research was to compare, in the subjects, the duration of the EMG silent period with jaw motion error. The results indicate that both jaw motion error and silent period duration are large in patients with TMJ-muscle-pain dysfunction, both are small in normal subjects, and both are small in successfully treated patients. There is a statistically significant correlation (r = 0.91; P < 0.01) between the two diagnostic parameters of TMJ-muscle-pain dysfunction.
Age and Race as Factors in Craniofacial Growth and Development
Authors: Harris James E. , Kowalski Charles J. , Levasseur Frances A. , Nasjlfti Carlos E. , Walker Geoffrey F.
Published: November 2010

Large samples of adult American black and white males are being studied to determine the extent to which age and race are important factors in craniofacial mophology and growth. It is shown that a number of dentofacial dimensions continue to change throughout adulthood and that the amount and direction of these changes may be race-specific. Applications in orthodontics and prosthetic dentistry are indicated.
Relationship of Streptococcus mutans Biotypes to Dental Caries Prevalence in Saudi Arabian Naval Men
Authors: Keene Harris J. , Shklair Irving L. , Anderson Dale M. , Mickel Gerald J.
Published: November 2010

A group of 217 Saudi Arabian naval recruits were examined clinically, radiographically, and microbiologically for the prevalence of Streptococcus mutans. Caries experience was considerably lower than in US recruits of comparable age and showed a significant positive correlation with the prevalence of S mutans in dental plaque samples. The distribution of S mutans biotypes and their relationship to dental caries in the Saudi Arabians were studied.
Stress in Dental Patients Undergoing Routine Procedures
Authors: Messer James G.
Published: November 2010

A method was devised to record graphically the stress that patients experience during routine dental procedures. Heart rate was used as the indicator and the variations in it showed which parts of the treatment provoked the maximum stress reactions. This pilot study indicated that by using this method it is possible to study specific dental problems and methods for treating them.
Investigation of Adhesive Properties of Dental Composite Materials Using an Improved Tensile Test Procedure and Scanning Electron Microscopy
Authors: Rider Marion , Tanker A.N. , Kenny B.
Published: November 2010

A standardized tension test was used to evaluate the adhesive properties of several composite materials when used on both dentin and enamel specimens. The nature of the test surfaces was examined by roughness tests using a Talysurf machine and also in more detail by means of a scanning electron microscope. Poor results were obtained for the adhesion of composite materials to dentin whereas good retention to enamel was obtained.
Microprobe Analysis of a High Cu Amalgam Alloy
Authors: Mahler David B. , Adey Jerome D.
Published: November 2010

Microprobe and X-ray diffraction analysis of a high Cu spherical alloy showed a minute dispersion of Cu 3Sn, γ(Ag3Sn), and β(Ag-Sn). The Sn-Hg (γ 2) phase was not detected in amalgams made from this alloy. The reaction phases were found to be γ1(Ag-Hg) and η(Cu6Sn 5).
Cyclic AMP in Dental and Periodontal Tissues During Tooth Eruption in Kittens
Authors: Gustafson Gunnar T. , Eckerdal Olof , Leever David L. , Shanfeld Joseph L. , Montgomery Paul , Davidovitch Zeev
Published: November 2010

Cyclic adenosine 3',5'-monophosphate (cAMY) concentrations and cellular distribution were studied in dental and periodontal tissues during tooth eruption in kittens. Although the mean levels of cAMP around developing teeth were similar in all the tissue samples, there were marked differences in cAMP stainability of tissues apical and occlusal to the erupting teeth.
Children's Response to Sequential Dental Visits
Authors: Venham L. , Bengston D. , Cipes M.
Published: November 2010

Behavioral, self-report, and physiological measures were used to study the response of young children to their initial series of dental visits. Their negative response increased from the examination visit through the third treatment visit, then decreased during the fourth treatment visit and the polish visit. Initially, dental experience appeared to sensitize the child to dental procedures. Experience may also allow the child to accurately distinguish between stressful and nonstressful procedures.
Fabrication and Characterization of Porous-Rooted Cobalt-Chromium-Molybdenum (Co-Cr-Mo) Alloy Dental Implants
Authors: Klawitter Jerome J. , Weinstein Allan M. , Peterson Larry J.
Published: November 2010

A gravity sintering fabrication technique has been developed for producing Co-Cr-Mo alloy dental implants having a porous coating on the root portion. This process allows for control of pore structure enabling ingrowth of either bone or fibrous tissue. The microstructure and mechanical properties of these materials have been determined.
Effect of Packing Pressure on the Abrasion Resistance of Dental Amalgams
Authors: Harrison Alan
Published: November 2010

Three dental amalgams were investigated to determine if their abrasion resistance was significantly affected by different packing pressures. Abrasive wear tests were performed on a machine designed to test materials under conditions similar to masticatory function. The results show that the abrasion resistance of the amalgams is unaffected by the packing pressure.
Surface Chemical Modification of Hard Tissues : I. Bone
Authors: Brauer G.M. , Termini D.J. , Levy S.M.
Published: November 2010

Surfaces of bone were modified in a controlled manner by grafting or by adding interpenetruting polymeric side chains to the bone substrate. The properties of the hard tissue surface attained varied widely. The surface alteration may improve the ability of hard tissues such as bone or dentin to adhere to restorative materials.
Immune Neutrality of Calf Skin Collagen Gel Used to Stimulate Revitalization in Pulpless Open Apex Teeth of Rhesus Monkeys
Authors: Donlon William C.
Published: November 2010

A collagen mineral gel has recently been shown to stimulate revitalization of pulpless open apex teeth when syringed into debrided root canals. Experiments were conducted to examine possible stimulation of the immune system by the experimental procedure. Ring tests (interface precipitation analysis), Ouchterlony plates and hemagglutination tests on plasma samples taken from experimental rhesus monkeys throughout the healing process indicate a complete lack of humoral immune responsiveness to the injected collagen.
Activity of Arginine Aminopeptidases and Phosphatases in Inflamed Palatal Mucosa in Denture Stomatitis: A Histochemical and Biochemical Study
Authors: Virtanen Kauko K. , Mäkinen Kauko K. , Oksala Erkki
Published: November 2010

Aminopeptidase and phosphatase activity of denture stomatitis mucosa was studied histochemically and biochemically. Stomatitis clearly increased the activity of these enzymes. An enzyme resembling the chloride-activated aminopeptidase B, usually involved in inflammatory processes, was recognized in the inflamed tissue in higher concentrations than in the control tissue.
Enamel Fluoride Uptake and Retention from Intensive APF Gel Applications In Vivo
Authors: Mellberg J.R. , Nicholson C.R. , Franchi G.J. , Englander H.R. , Mosley G.W.
Published: November 2010

Children in a fluor dated water area self-applied acidulated phosphate fluoride (APF) gel (pH3.2) on 5, 10, or 25 consecutive school days. Analysis of exfoliated deciduous teeth showed that F concentrations in enamel increased to high levels during the treatment periods. Following the treatments, F levels decreased significantly for 2-10 months, after which the remaining F appeared permanently bound.
The Measurement of the Effect of Toothbrushes on Soft Tissue Abrasion
Authors: Alexander J.F. , Saffir A.J. , Gold W.
Published: November 2010

The effect of toothbrushes on soft tissue abrasion was measured using hamster cheek pouch tissue brushed mechanically for various intervals. The detection of protein removed during brushing was used as an index of tissue abrasion. The method was found to be sensitive in detecting the effects of brush load, number of strokes applied, and the texture of the brush. The results further showed that the mechanical removal of sharp edges from bristle tips substantially reduced the level of soft tissue abrasion while a dentifrice polishing agent applied to the tissue with a brush did not increase the abrasive effect of the brush.
Fracture Toughness of Composite and Unfilled Restorative Resins
Authors: Roberts J.C. , Powers J.M. , Craig R.G.
Published: November 2010

Fracture toughness, critical strain energy release rate, and critical stress intensity factor were determined for experimental and commercial restorative resins. A composite resin had lower resistance to arack initiation than an unfilled acrylic resin. The data were consistent with surface failure observed in single-pass wear studies of these resins.
Electromyographic Analysis of the "Buccinator Mechanism" in Human Beings
Authors: Perkins Ronald E. , Blanton Patricia L. , Biggs Norman L.
Published: November 2010

Electromyography of the muscles of the "buccinator mechanism" was undertaken, utilizing indwelling fine-wire electrodes. Electromyograms were made of 14 subjects with normal occlusion during various oral activities. Several activities elicited simultaneous contraction of all muscles. Simultaneous activity represents a potential restraining force of this muscular band on the dentition.
Morphological Changes to Lymphatic Vessels in Pulpal Inflammation
Authors: Bernick Sol
Published: November 2010

Noncarious, carious, and restored human teeth obtained from individuals 20 to 65 years of age were used to study the differences in lymphatic drainage between healthy and inflamed pulps. In carious teeth, the lymphatic vessels located within and/or surrounding the inflammatory lesion were distended, a situation not demonstrable in pulps of noncarious and restored teeth.
Collaborative Evaluation of a Rat Caries Model in Six Laboratories
Authors: Larson R.H. , Amsbaugh S.M. , Navia J.M. , Rosen S. , Schuster G.S. , Shaw J.H.
Published: November 2010

When highly controlled parallel rat caries studies were run simultaneously in six laboratories, a similar pattern of caries developed in every laboratory with a range in mean values such that the results of no investigator were significantly different from those of at least two others. These results indicate that the major factors influencing development of rat caries have been recognized and can be controlled within reasonable limits.
A Chromatographic Study of the Relative Affinities of Rat Bone and Skin Collagen 1 Chains for Hydroxyapatite
Authors: Nawrot C.F. , Campbell D.J.
Published: November 2010

The affinity of a bone collagen α1 chain for hydroxyapatite has been compared to a similarly isolated skin component from the same animals. The chain from bone exhibits a higher affinity for the mineral. This enhanced affinity appears to be related to its primary structure, specifically its hydroxylysine moieties.
The Effect of Procion Blue on Certain Metabolic Activities of Streptococcus mutans
Authors: Vicher E.E. , Iqbal M. , Waterhouse J.P.
Published: November 2010

Metabolic activities of S mutans were selectively affected by Procion Blue, known to cause covalent bonds and stable cross links in relation to carbohydrate and protein. In this study, despite the reduction in extra polysaccharide, the level of activity of glucosyltransferase was not significantly changed from the control level and colonial morphology was not transformed from smooth to rough. The results of the investigation imply at least interference with formation of extracellular polysaccharide, possibly in the bacterial cell wall.
The Electron Microscopy of Bacteriophage-like Particles in Dental Plaque
Authors: Brady John M. , Gray Walter A. , Caldwell Margaret A.
Published: November 2010

The morphology of bacteriophage-like particles contained in samples of dental plaque is described. The phage-like particles were observed within fusiform-shaped bacteria and in clumps between bacteria. The particles were hexagonal in cross section, approximately 1,100 nm in diameter and contained an electron-dense core. In areas of cell lysis, tail forms were observed both free and in association with the particles. Occasional particles were attached to bacterial cell walls by means of shortened tailpieces.
Root Surface Caries in the Molar Teeth of Rice Rats. II. Quantitation of Lesions Induced by High Sucrose Diet
Authors: Doff Richard S. , Rosen Samuel , App George
Published: November 2010

Weanling rice rats were fed either standard laboratory chow or Diet 2000. The animals were sacrificed at 4, 8, 12, and 15 weeks. There was an increasing amount of exposed root surface and root surface caries with age in the animals fed Diet 2000. There was exposed root surface but no caries in the animals fed laboratory chow.
Polyacrylamide Gel Electrophoresis of Human Salivary Histidine-Rich-Polypeptides
Authors: Baum Bruce J. , Bird Janice L. , Longton Robert W.
Published: November 2010

A method of polyacrylamide gel electrophoresis for examining histidine-rich-polypeptides in human saliva is described. Comparison is made to several commonly used electrophorretic techniques. The described method allows for the resolution of seven histidine-rich-polypeptide fractions and is convenient and quite reproducible.
Phagocytosis of Latex Beads by a Human Gingival Epithelial-Like Cell Line in Tissue Culture
Authors: Pinero G.J. , White R.R.
Published: November 2010

Phagocytosis by a human gingival epithelial-like cell line in tissue culture was studied using latex beads as a marker. Electron microscopic and chemical analyses revealed that the cells ingested the beads in a quantitative and reproducible manner. This phagocytosis system is potentially useful for studying the effects of dental plaque on cell metabolism.
Lead in Enamel and Saliva, Dental Caries and the Use of Enamel Biopsies for Measuring Past Exposure to Lead
Authors: Brudevold F. , Aasenden R. , Srinivasian B.N. , Bakhos Y.
Published: November 2010

Enamel biopsies taken from schoolchildren in a community where exposure to lead was a health hazard were analyzed for lead and fluoride. The children with high enamel lead had significantly higher caries scores than the children with low enamel lead, in spite of the fact that the high lead group also was higher in enamel fluoride. There was no increase in enamel lead with age. The lead in saliva was only a fraction of that in blood. Infants with lead poisoning showed higher saliva lead than a normal infant. The use of the lead in enamel biopsies and in saliva for measuring exposure to lead is discussed.
Quantification of Pulpal Blood Flow in Developing Teeth of Dogs
Authors: Path Michael G. , Meyer Maurice W.
Published: November 2010

Pulpal blood flow in developing teeth was determined by the isotope fractionation method incorporating diffusible and nondiffusible tracers. While the calculated blood flow to some cephalic tissues did vary according to tracer, blood flow to the total pulp remained essentially the same throughout tooth development.
Effects of Repeated Ingestion of Large Quantities of Acetylsalicylic Acid on Membranous Bone Growth and Dentin Apposition in Young Monkeys
Authors: Yen Peter K-J. , Shaw James H.
Published: November 2010

Four oral doses of acetylsalicylic acid at 325 mg/kg body weight were given to young monkeys that received a series of injections of lead acetate as an intravital stain. Bone growth, including remodeling of the Haversian canal system, was greatly inhibited, whereas dentin apposition was unaffected.
An Analysis of Three Mixed Dentition Analyses
Authors: Kaplan Ross G. , Smith Charles C. , Kanarek Paula H.
Published: November 2010

The accuracy of prediction of three mixed dentition analyses was compared. Hixon and Oldfather's method was found to be the most accurate. A simplified version of the analysis obviates referral to a table, allowing assessment of the size of the unerupted teeth prior to eruption of the lateral incisor.
Radiation-Induced Epithelial-Submucosal Separation: An Electron and Light Microscopical Investigation
Authors: Sandstrom Nils F. , Goepp Robert A.
Published: November 2010

Irradiation injury of the mouse tongue was studied by electron and light microscopy. A specific lesion was found to be the result of edema. Epithelial compensation was seen in the form of proliferation of desmosomes and hemidesmosomes, elongation of rete ridges, and hypertrophy of cytoplasmic projections from basal cells.
Degenerative Changes in Masseter Muscle Following Injection of Lidocaine : A Histoehemical Study
Authors: Dolwick M.F. , Bush F.M. , Seibel H.R. , Burke G.W.
Published: November 2010

Changes in suceinic dehydrogenase, adenosine triphosphatase, and phosphorylase activities occurred in masseter muscle by 15 minutes following injeetion of 2% lidocaine. Abolishment of phosphorylase activity suggested an effect on the sarcoplasmic retieulum. Increased staining for succinic dehydrogenase and adenosine triphosphatase activities suggested damage to mitochondria and myofibrils, respectively. Leucine aminopeptidase and glucose-6-phosphate dehydrogenase activities appeared in macrophages.
A Study of Oxidation of Dental Amalgams with Age
Authors: Garner Claudia K. , Miller George E. , Volborth Alexis
Published: November 2010

A quantitative test for corrosion due to oxidation has been accomplished. The oxygen concentration of dental amalgams was measured by fast neutron activation which provides a means of detecting oxygen in as small a quantity as 10 to 20 micrograms. An increase in oxygen content with age of spherical blend amalgam implants was observed, confirming the importance of oxidation processes in in vivo corrosion.
The Antibacterial Action of the Various Components of the Lactoperoxidase System on a Cariogenic Strain of Streptococcus mutans
Authors: Tenovuo Jorma , Knuuttila Matti L.E.
Published: November 2010

Physiological activity of lactoperoxidase and in vivo concentration of thiocyanate ions were shown to be inhibitory against a cariogenic strain of Streptococcus mutans. However, the amount of H2O2 in vivo may be too low for optimum inhibition by lactoperoxidase system. H2O2 alone also inhibited the growth of S mutans to some degree.
Relationship Between the Populations of Streptococcus mutans in the Mouth and Feces of Conventional Sprague-Dawley Rats
Authors: Huber G. , Van Houte J. , Edelstein S.
Published: November 2010

The relationship between oral and fecal S mutans populations has been studied in rats fed high sucrose or glucose diet. All molar teeth were extracted either prior to or following oral challenge with strain 6715. In certain instances this procedure was supplemented with amputation of the incisors and disinfection of the remaining incisor surface area with iodine solution. The results suggest that in rats the colonization of S mutans on the teeth is required for its presence in the intestinal canal as well as the mouth. The significance of the observations has been discussed.
The Bilateral Response of the Temporal Muscle in the Rhesus Monkey (Macaca mulatta) to Short-Term Detachment of the Muscle and Increased Loading of the Mandible
Authors: Miller Arthur J. , Chierici George
Published: November 2010

The electromyographic background activity of the temporal muscle was observed after short-term detachment of the muscle and with increased loads on the mandible. Detachment of the muscle increased its mean spike discharge within the first 24 days but without significant changes in the spectral components. Loading the mandible decreased both the spike discharge and spectral components.
The Effects of Human Saliva on the Hemolytic Activity of Complement
Authors: Boackle Robert J. , Pruitt Kenneth M. , Silverman M.S. , Glymph John L.
Published: November 2010

Human saliva was tested for the presence of factors that affect the complement system. Parotid saliva and salivary fractions were incubated at 37 C with human serum as a source of complement. Samples removed from the mixtures within the first 15 minutes had higher levels of whole hemolytic complement activity than did appropriate controls. The final ionic strength of the saliva-serum mixtures was critical to the hemolytic activity of complement. After 60 minutes all serum-saliva mixtures had lower levels of hemolytic activity than did serum-buffer controls. With regard to whole saliva, the salivary sediment was found to be strongly complement-reactive.
Selective Habitation of Bacteria on "Intermediate Soft" Keratin Surfaces of the Rat Tongue
Authors: Kaster A.G. , Cameron I.L.
Published: November 2010

Scanning and light microscopy reveals a selective and restrictive pattern of indigenous bacterial colonization on the tongue of rats which is accounted for by the preferred attachment of bacteria to an "intermediate soft" keratin substrate. Total intravenous feeding of rats for 10 days did not alter this colonization pattern indicating that oral intake of food is not responsible for maintenance of this pattern.
A Contribution to the Histological Study of Hypercementosis Using Metal Staining
Authors: Comellilia Raphael Carlos , Lauand Fauze , Marcantonio Elcio , Benatti Neto Carlos
Published: November 2010

The authors made a detailed study of hypercementosis using metallic procedures.
Changes in Consistency of Occlusal Contact in Myofascial Pain-Dysfunction (MPD) Syndrome
Authors: Edmiston G. Frederick , Laskin Daniel M.
Published: November 2010

The sound patterns produced by tooth contact were recorded in 24 subjects with myofascial pain-dysfunction (MPD) syndrome prior to and following treatment using an Occlusograph. Recordings also were obtained on 12 control subjects. Evaluation of the sound patterns showed a close correlation between the improvement in symptoms of MPD syndrome following treatment and the consistency of repeated occlusal contacts. The consistency following successful treatment of the subjects with MPD syndrome was equivalent to that of the control subjects.
Alterations in Lactoferrin in Salivary Gland Disease
Authors: Tabak Lawrence , Mandel Irwin D. , Karlan Daniel , Baurmash Harold
Published: November 2010

During the active phase of chronic recurrent parotitis there is a marked elevation in the parotid concentration of lactoferrin (Lf), an iron-binding glycoprotein with antibacterial properties. The Lf concentration decreases during the recovery period, but still remains above normal levels. The changes of Lf in parotitis parallel recent findings in mastitis and pancreatitis. Elevations in Lf were also noted in five of six subjects with Sjögren's disease, but not in subjects with sarcoidosis, diabetes or "dry mouth" without sialographic changes. The source of the Lf has not been determined; it could arise in part from disrupting polymorphonuclear leucocytes and in part from epithelial cells that synthesize Lf in the salivary glands. Inflammatory stimulation of Lf synthesis would suggest a basic protective mechanism in exocrine glands and should be fully explored.
Relationship of Strontium in Drinking Water and Surface Enamel
Authors: Spector P.C. , Curzon M.E.J.
Published: November 2010

The Sr content of surface enamel of 233 teeth from nine communities was related to drinking water Sr concentrations. These water concentrations ranged from 0.02 μg/ml to 33.9 μg/ml. The relationship between enamel concentrations and water concentrations was linear for water concentrations less than 10μg/ml Sr, but leveled off at approximately 300 μg/gm Sr in the enamel for communities with greater than 10 μg/ml Sr in drinking water. Binding of Sr to components in the oral environment is proposed as an explanation of this effect.
Reduction in Enamel Dissolution by Liquorice and Glycyrrhizinic Acid
Authors: Edgar W.M.
Published: November 2010

Liquorice extracts and confections reduced enamel dissolution in acidic buffers and saliva/ glucose incubations by a direct effect on solubility, and by inhibiting the fall in pH on incubation. These actions may be attributed to the solubility-reducing, glycolysis-inhibiting, and buffering properties of glycyrrhizinic acid, a constituent of liquorice.
Effects of Indomethacin Upon I Uptake by Thyroid and Submaxillary Glands in Mice
Authors: Houssay A.B. , Gamper C.H. , Arias N.H. , Curbelo H.M.
Published: November 2010

The administration of indomethacin to male A2G mice induced a marked decrease in the 131 I uptake by the thyroid, but it did not influence the 131I uptake by the submaxillary glands.
An Ultrastructural Study of the Formation of "Dark" and "Light" Cytoplasmic Inclusions by Murine Cytomegalovirus in Mouse Submandibular Gland
Authors: Joseph Charles E. , Grand Nicholas G. , Pumper Robert W.
Published: November 2010

Electron micrographs of acinar cells of the submandibular glands of CFW mice infected with murine cytomegalovirus, Smith strain, were studied. The resulting viral intracytoplasmic inclusion bodies were classified into two groups termed "light" (relatively electron-lucent) and "dark" (relatively electron-dense). It appeared that the "dark" type was the late stage of inclusion body maturation.
Metal-Filled Resin Composites. II
Authors: Bowen R.L. , Chandler H.H. , Wyckoff H.O. , Misra D.N.
Published: November 2010

Various particulate materials were combined with a BIS-GMA resin, and the resulting composites were evaluated. The fillers prevented, altered, had no apparent effect, or accelerated polymerization. Coupling agents also influenced polymerization. Physical properties varied widely with different fillers.
The Rheological Properties of Fluid Denture-Base Resins
Authors: Vermilyea S.G. , Powers J.M. , Koran A.
Published: November 2010

The rheological properties of six commercial fluid denture resins were determined by rotational viscometry. Initial viscosity ranged from 67 to 575 centipoise at a rotational speed of 10 revolutions per minute. All resins showed initial non-Newtonian flow behavior and increased viscosity with time.
Effect of Surface Preparation on Phase Distribution of Amalgam Surfaces
Authors: Boyer Daniel B. , Edie John W. , Kai Chiu Chan
Published: November 2010

Several types of amalgams were prepared with carved, burnished, or polished surfaces. Elemental analyses were made of these surfaces with the electron microprobe and the phase fractions were calculated from these data. The phase distributions were found to vary with the technique of finishing.
Basic Biological Sciences Pre-apatitic Mineral Deposition in Bacterionema matruchotii
Authors: Boyan-Salyers Barbara D. , Vogel James J. , Ennever John
Published: November 2010

A preliminary examination of calcification of Bacterionema matruchotii was undertaken to provide a base-line for future kinetic and mechanistic studies. Specific ion ratios were correlated with crystallography and ultrastructure. Observations include: three consistent X-ray diffraction patterns; no resolution of cellular EMP by electron microscopy; increasing Ca/Mg, Ca/P during calification.
An Electrochemical Study on the Human Dental Enamel with Special Reference to Isoelectric Point
Authors: Kambara Masaki , Asai Teruyoshi , Kumasaki Mamoru , Konishi Koji
Published: November 2010

In an attempt to make a dynamic study of the isoelectric point and the chargeability of human dental enamel, an electrochemical approach was utilized. Zeta potential of three kinds of the enamel was measured by a streaming potential method. As a result, these isoelectric points could be decided.
Evidence for the Presence of Carbamino Compounds in Human Saliva
Authors: Izutsu Kenneth T. , Madden Phillip R.
Published: November 2010

The bicarbonate concentrations of whole saliva and of protein-free filtrates of saliva were measured to test for the presence of carbamino compounds. If no acid-evolved CO2 were derived from the salivary proteins, then the two measured bicarbonate concentrations should be identical. Instead, the bicarbonate concentrations of the whole saliva samples were on the average 30% higher than that of their filtrates. The results are consistent with the conclusion that carbamino compounds account for the differences. Similar findings were obtained with samples of resting whole saliva and parotid saliva.
Metabolism of Gingival Collagen in a Rat
Authors: Orlowski Walter A.
Published: November 2010

The remodeling of gingival tissue was measured by determining the incorporation of tritiated proline and the disappearance of tritium activity from proline and hydroxyproline for 18 days after administration of label. There was a rapid decrease in the tritium activity from gingiva which was paralleled by a decrease in the total activity of proline. The activity in collagen decreased sharply between the second and the fourth day but thereafter there was no change. The relative amount of activity increased from 24% at day 2 to 82% at 18 days postinjection, and as a result the specific activities of hydroxyproline and proline were similar after 12 days. Thus collagen appeared to be the more stable component in the gingivae than previously reported. However, the rapid loss of label in the first four days suggested that there may be very marked regional variation in the metabolism of collagen and that more than one metabolic pool of collagen was present.
Semiconductor Probe Measurements in Beagle Dogs with Periodontal Disease
Authors: Kaplan M.L. , Jeffcoat M.K. , Goldhaber P.
Published: November 2010

A miniaturized semiconductor probe was used to measure alveolar bone uptake of a bone-seeking radzopharmaceutical in dogs with destructive periodontal disease. Radiopharmaceutical uptake in localized, advanced disease was greater than in incipient disease and was generalized, with increased uptake occurring in radiographically normal areas and in areas with bone loss.
Influence of Hexetidine Upon Plaque and Gingivitis in the Beagle Dog
Authors: Mcdonald James L. , Schemehorn Bruce R. , Stookey George K.
Published: November 2010

Two studies were performed in beagle dogs to determine the effect of 0.2% hexetidine upon plaque and gingivitis. In both instances, hexetidine exerted no significant effect while 0.2% chlorhexidine resulted in reductions in both plaque and gingivitis of about 45 and 50%, respectively.
Antimicrobial Agents and Dental Caries in the Rat
Authors: Mcdonald James L. , Stookey George K.
Published: November 2010

Two rat plaque-caries studies indicated that a 0.2% chlorhexidine solution topically applied to rat teeth was effective in reducing dental plaque. This reduction in plaque was accompanied by marked reductions in smooth surface caries, but not in sulcal lesions.
The Effects of Cadmium on the Growth of Some Oral Microorganisms and Their Ability to Bind Cadmium
Authors: Beighton D. , Mcdougall W.A.
Published: November 2010

All seven oral Actinomycetaceae tested grew in broth containing 10 μg/ml Cd. After 24 hours' growth A viscosus WVU 626 bound nearly 20 μg Cd/mg dry wt. The amount of Cd bound varied during the growth cycle, being maximal (90 to 100 μg/mg dry wt.) after 5 hours' growth. Addition of 50 μg/ml chloramphenicol to actively growing cells inhibited further Cd binding. In contrast S mutans FA1 was greatly inhibited by 2.5 μg/ml Cd and bound only 1.3 μg Cd/mg after 24 hours' growth in broth containing 2.5 μg/ml Cd.
Remodeling of Cancellous Bone in Young Monkeys
Authors: Yen Peter K-J. , Moin Kambiz , Shaw James H.
Published: November 2010

Remodeling of the trabeculae in cancellous bone was studied in young monkeys that received multiple weekly injections of lead acetate as a marker. Resorption of old bone and deposition of new bone were demonstrated. The rate of deposition of new bone varied at different sites of the same trabeculae and also at different time intervals of the same site. The total formation time of new bone to fill the trabecular space was estimated.
Plaque Minerals and Caries Experience: Associations and Interrelationships
Authors: Schamschula R.G. , Bunzel M. , Agus Helen M. , Adkins B.L. , Barmes D.E. , Charlton G.
Published: November 2010

Inverse associations were demonstrated between DMFT and total calcium, phosphorus, magnesium, strontium, potassium, and fluoride concentrations in individual plaques. Lithium, strontium, fluoride, and zinc contents were inversely related to plaque mass. Consistent interdependence patterns between elements indicate the operation of a mineral level regulating mechanism, effective under diverse environmental conditions.
Dental Caries and Socioeconomic Status in Mexican Children
Authors: De La Rosa R. Manuel
Published: November 2010

A dental caries survey of 2,445 Mexican children, 6 to 15 years of age, was conducted in an industrial city. The children were divided into three socioeconomic groups. The pattern of the caries attack rate conformed to all caries surveys. However, the DMFT and DMFS scores increased as the socioeconomic levels increased. The higher socioeconomic groups presented evidence of more dental care than the low group.
Measurements of Cervical Undercuts of Human Tooth Crowns
Authors: Hisamitsu Hisashi , Iwaku Masaaki , Fusayama Takao
Published: November 2010

The dimensional factors of the cervical undercut of the human teeth were measured. The faciat and lingual undercuts showed considerable deviations in depth, width, and inclination to the crown axis and the food stream. The proximal undercuts showed a uniform depth of 1 ± 0.3 mm with some deviations in width and inclination.
Aldehyde Methacrylates Derived from Hydroxybenzaldehydes
Authors: Antonucci Joseph M.
Published: November 2010

Aldehyde methacrylates were synthesized from the 3 isomeric hydroxybenzaldehydes by facile condensation reactions. The 3 monomers are relatively low-melting crystalline solids which can be liquified by simple admixture of the isomers.
Effect of Progestins on Androgen Δ4-3-Ketosteroid-5α-A-Ring Reductase System in Rat Oral Mucosa
Authors: Vittek J. , Altman K. , Rappaport S.C. , Gordon G.G. , Hagedorn J. , Southren A.L.
Published: November 2010

Rat oral mucosa microsomal Δ 4-3-ketosteroid-5α-A-ring reductase enzyme system, reducing testosterone and 4-androstenedione, was found to be inducible by systemic administration of medroxyprogesterone acetate (MPA). MPA, when used in a mixture with testosterone and/ or 4-androstenedione in vitro, acted as a competitive inhibitor of the reduction of these substrates.
Enhanced Collagenase Activity in Diabetic Rat Gingiva: In Vitro and In Vivo Evidence
Authors: Golub Lorne M. , Schneir Michael , Ramamurthy N.S.
Published: November 2010

Gingiva from alloxan and streptozotocin-diabetic rats exhibited markedly enhanced collagenolytic activity in tissue culture. This effect was eliminated by puromycin or by repeated freeze-thawing of the tissue prior to incubation. Soluble extracts of the diabetic gingiva in situ were found to contain breakdown products of collagen similar in size to the reaction products generated by tissue collagenase. These fragments were not detected in the control tissue. This study indicates that experimental diabetes stimulates the synthesis of gingival collagenase in culture and that a similar effect occurs in vivo.
Fluoride Uptake and Caries Rate in Hamster Molars after Topical Fluoride Application Followed by Acidulation
Authors: Nathaniel A. , Gedalia I. , Anaise J. , Daphni L.
Published: November 2010

Daily topical application of 2% NaF on hamster molars for 4 days in vivo, followed by acidulation (grapefruit beverage, pH 3.3) resulted in a lower caries rate than NaF followed by water application. Fluoride uptake was somewhat higher, but not significantly so in the acidulated group.
Thermal Stress in Teeth
Authors: Lloyd B.A. , McGinley M.B. , Brown W.S.
Published: November 2010

Observations of crack damage in the tooth structure from in vivo studies and in vitro experimental thermal cycling studies were combined with numerical analysis techniques to identify and isolate the influence of thermal stresses an the creation and propagation of cracks in teeth. The factors considered in this study included: (a) variations in tooth type or geometry (molar, bicuspid, etc.), (b) tooth age, (c) material properties of the tooth, (d) the magnitude of the change in the temperature of the environment surrounding the tooth, and (e) the thermal resistance between the tooth and the medium surrounding the tooth.
Bending Deformation Studies of Orthodontic Wires
Authors: Brantley William A. , Augat William S. , Myers C. Louis , Winders Robert V.
Published: November 2010

Bending deformation has been measured for orthodontic wires ranging in diameter from .010 to .051 inch. Results establish a revised expression for Young's modulus and show that either the stiffness tester or the torque meter will yield essentially the same measured values of bending properties. The dependence of test span length in determining Young's modulus and flexural yield strength is discussed.
Effect of Isoprenaline on Salivary Gland Lipids of Rats Fed a Choline-Deficient Diet
Authors: Alam Syed Q. , Alam Bassima S.
Published: November 2010

Male adult rats were fed choline deficient and a choline-supplemented diet for 3 weeks. Half the rats from each group were injected with isoprenaline (16 mg/kg body wt.) and the remainder with saline. After 2 and 8 hours, rats were sacrificed, their submandibular salivary glands (SMSG) were disected out, and extracted for lipids. The fatty acid composition of total lipids and some neutral and phospholipid fractions were determined. Isoprenaline administration resulted in a slightly higher level of oleic acid in SMSG of rats fed choline-deficient but not the control diet. There was an increase in the free fatty acid (FFA) concentrations of the gland after 2 hours of isoprenaline treatment in rats fed the control diet; no such increase was observed in the choline-deficient group. The fatty acid composition of the FFA fraction was also slightly changed as a result of isoprenaline treatment, but only in the choline-deficient group. The fatty acid composition of triglyceride (TG), phosphatidyl choline (PC), and phosphatidyl ethanolamine (PE) fractions was not changed.
TMJ Symptom Severity and EMG Silent Periods
Authors: Mccall W.D. , Uthman A.A. , Mohl N.D.
Published: November 2010

The hypotheses that latency or duration of the EMG silent period evoked by a tap to the chin during a maximal clench would be more prolonged in more severe TMJ patients were tested. The mean latency did not, and the mean duration did, increase significantly with increased severity of TMJ dysfunction.
New Information on High Copper Amalgam Corrosion
Authors: Fairhurst C.W. , Marek M. , Butts M.B. , Okabe T.
Published: November 2010

Anodic polarization of "pure" Cu6 Sn5 was investigated. Cu 6 Sn5 is found to be passive in nearly neutral synthetic saliva. Anodic corrosion activity (characteristic for tin) previously reported for a high copper amalgam must result from the presence of the γ 2 phase or tin in the matrix phase.
Acetylcholine and Cholinesterase in Submandibular Glands of Rats Given Armin and Obidoxime
Authors: Vasic Bogoslav V. , Milosevic Milenko P. , Terzic Milorad R.
Published: November 2010

The effects of obidoxime, a pyridinium oxime, on the cholinesterase activity and acetylcholine content of the submandibular glands of rats poisoned with armin, an organophosphorus anticholinesterase agent, were studied. The results indicate that obidoxime-induced reactivation of phosphorylated cholinesterase can suppress completely the increase in the concentration of acetylcholine that develops within the submandibular gland after administration of armin alone.
Alteration of Lidocaine-Induced Convulsions by Meperidine and Nitrous Oxide
Authors: Gangarosa Louis P. , Ciarlone Alfred E. , Hung Ching
Published: November 2010

When mice were pretreated with meperidine, the incidence of lidocaine-induced convulsions was increased. Nitrous oxide-oxygen (N2O-O2) offered no protection against convulsions caused by lidocaine alone but lowered the incidence of lidocaine-induced convulsions of mice pretreated with meperidine.
Lymphatic Vessels of Healthy and Inflamed Gingiva
Authors: Bernick Sol , Grant Daniel A.
Published: November 2010

Lymphatic vessels were traced in healthy and early inflamed gingivae of various nonhuman primates. Lymphatic capillaries and primary collecting vessels originated in the connective tissue papillae and stroma near or adjacent to the attachment epithelium. They emptied into thin-walled irregular-shaped collecting vessels that drained into the periodontal ligament. In early inflammation, all the lymphatic vessels of luminal caliber were distended within and/or surrounding the inflammatory infiltrate.
Micropuncture Study of Postnatal Functional Maturation of the Rat Parotid
Authors: Mangos John A.
Published: November 2010

The postnatal function maturation of the rat parotid was investigated using micropuncture and microanalytical techniques. The cationic composition of the luminal fluid at different levels of the duct system, the net transductal fluxes of Na, K, and H2O and the salivary excretion of protein and amylase in immature and mature rats were determined.
Interrelations of Oral Microorganisms, Immunoglobulins, and Dental Caries Following Radiotherapy
Authors: Brown Lee R. , Dreizen Samuel , Daly Thomas E. , Drane Joe B. , Handler Sandra , Riggan Linda J. , Johnston Dennis A.
Published: November 2010

Of 42 head and neck cancer patients with radiotherapy-induced xerostomia, 36 survived to permit a postirradiation caries evaluation. Twenty-three developed an average of 17.6 caries lesions and 13 had no new lesions within 30 months postirradiation. All caries-inactive patients had been initially assigned to daily self-application of a 1% sodium fluoride gel. The preirradiation caries experience and the oral microbial profile were comparable in both groups. After tumoricidal irradiation, the mean plaque increase of Streptococcus mutans was 25 times greater in the caries-active than in the caries-inactive group. Postirradiation caries was also associated with increased plaque Lactobacillus sp, Candida sp, and Streptococcus sp, and serum IgD and IgG concentrations. Conversely, plaque Staphylococcus sp, Streptococcus salivarius, and Veillonella sp and saliva IgA concentrations were significantly higher in the caries-inactive than in the caries-active group. Both groups demonstrated decreases in plaque Streptococcus sanguis, Neisseria sp, Fusobacterium sp, and Bacteroides sp.
Influence of Fluoride upon Plaque and Gingivitis in the Beagle Dog
Authors: McDonald James L. , Scheniehorn Bruce R. , Stookey George K.
Published: November 2010

Two studies were conducted to explore the effects of twice daily topical applications of NaF, SnF 2, and an amine fluoride at equivalent fluoride concentrations (0.1%) upon plaque and gingivitis in the dog. Although some trends toward modest benefits were noted in certain instances, none of the agents exerted a significant effect upon either parameter.
In Vivo Analysis of Bone Strain about the Sagittal Suture in Macaca mulatta during Masticatory Movements
Authors: Behrents Rolf G. , Carlson David S. , Abdelnour Thomas
Published: November 2010

In vivo strain gauge analysis demonstrated that tensile bone strain is transmitted along the cranial vault to the parasagittal region during isotonic temporalis contraction. This strain is sufficient to cause measurable separation of the sagittal suture, and thus could influence growth at the sutural margins.
Adsorption of Streptococcus mutans on Chemically Treated Hydroxyapatite
Authors: O'Brien W.J. , Fan P.L. , Loesche W.J. , Walker M.C. , Apostolids A.
Published: November 2010

Adsorption of Streptococcus mutans on hydroxyapatite and chemically treated hydroxyapatite was studied. Zeta potentials of the surfaces were measured. Chemically treated hydroxyapatite gave higher ζ potentials and lower S mutans adsorption.
The Effect of NaF on the Bacterial Production of Polysaccharide and Subsequent Adsorption on Hydroxyapatite
Authors: Shimura Norio , Onisi Masao
Published: November 2010

The affinity of some bacterial polysaccharides for hydroxyapatite was investigated. Water insoluble polysaccharide production by bacteria was inhibited by the presence of NaF in the growth medium, while the water soluble fraction was unaffected. The adsorption of the bacterial polysaccharide on hydroxyapatite decreased with decreasing levels of the water insoluble fraction. It is suggested that NaF can inhibit bacterial attachment and caries by interfering with bacterial attachment through reducing the production of water insoluble polysaccharide.
Modification of Human Parotid Saliva Proteins by Oral Streptococcus sanguis
Authors: Choih Sun-Jin , Smith Quenton T. , Schachtele Charles F.
Published: November 2010

Polyacrylamide gel electrophoresis was used to analyze the effect of Streptococcus sanguis on the anionic proteins in human parotid gland saliva. Cell-free culture supernatants and washed-cell preparations from 23 strains of S. sanguis caused marked modification of various salivary proteins. Control studies showed that the alterations in protein profiles by the bacteria were not due to attachment of protein to the cells. Protease inhibitors were used to confirm that proteolysis by distinct enzymatic activities was responsible for most of the modifications. There was no discernible relationship between the degradation patterns and the various immunologic or genetic groups of S. sanguis. Proteins which contained high concentrations of proline were extensively degraded by S. sanguis. This effect could be blocked with the protease inhibitor phenylmethylsulphonyl fluoride.
The Chloride Corrosion of Low-Gold Casting Alloys
Authors: Sarkar N.K. , Fuys R.A. , Stanford J.W.
Published: November 2010

Potentiodynamic polarization measurements have indicated that the so-called 'low-gold' casting alloys are characterized by decreased chloride corrosion resistance, when compared with ADA Type III and Type IV gold alloys. This decrease in chloride corrosion resistance results apparently from the presence of Ag-rich microsegregations with a possible minor contribution from Curich segregations or precipitates.
Proteolytic Activity in Developing Bovine Enamel
Authors: Moe D. , Birkedal-Hansen H.
Published: November 2010

Partially mineralized enamel matrix removed from bovine incisor tooth germs contains proteolytic activity capable of completely degrading enamel matrix proteins at neutral and slightly alkaline pH. The protease activity also degrades common protease substrates such as casein and azocoll with optimal activity at pH 8-9. Inhibitor studies revealed that the enzyme involved is a serine protease of the chymotrypsin family.