bluuebunny/crossref_metadata_2025 huggingface dataset:
Utilization of Cation-Selective Membranes in the Study of Caries Formation
Authors: Harrison Craig A.
Published: November 2010

A caries mechanism was tested in a model experiment in which cation-permselective membranes were used to simulate the outer enamel-plaque layer. According to this theory, preferential diffusion of Ca2+ and H+ accelerates caries formation. The results support the theory and confirm that activity of Ca(OH)2 is of fundamental importance.
Elastic Properties of Dental Resin Restorative Materials
Authors: Nakayama Wayne T. , Hall David R. , Grenoble Dale E. , Katz J. Lawrence
Published: November 2010

The elastic constants of several commercially available filled and unfilled dental resin restorative materials were determined in the 0 to 50 kilobar range of pressure. Measurements of the velocities of propagation of longitudinal and shear ultrasonic waves were used to obtain the Young's, bulk, and shear moduli and Poisson's ratio as a function of pressure; atmospheric pressure values were obtained by back extrapolation from the high pressure data.
Lead Content of Human Blood, Hair, and Deciduous Teeth: Correlation with Environmental Factors and Growth
Authors: Habercam Julian W. , Keil Julian E. , Routt Reigart J. , Croft Harriet W.
Published: November 2010

Determination of lead content of deciduous teeth may provide a useful index to previous lead exposure.
Effects of Testosterone Propionate on Sialic Acid Content of Submaxillary and Retrolingual Glands in the Rat
Authors: Curbelo Halina M. , Gamper Carlos H. , Kofoed Jorge A. , Tocci Antonio A.
Published: November 2010

Castration in male rats decreased and the administration of testosterone propionate to castrated male rats increased the sialic acid concentration in the submaxillary glands but did not change that of the retrolingual glands. Plasmatic sialic acid concentration was increased in the animals receiving testosterone propionate.
Morphology, Composition, and Wetting of Dentinal Cavity Walls
Authors: Hoppenbrouwers P.M.M. , Driessens F.C.M. , Stadhouders A.M.
Published: November 2010

The morphology of dentinal cavity walls, wetting by poly (methyl methacrylate), and resistance to tensile forces was studied with a scanning electron microscope, before and after etching or fixation, or both, with glutaraldehyde. Results indicated that the surface layer of dentinal cavity walls after etching is of an aqueous-organic nature, that glutaraldehyde fixation improves the mechanical properties of the surface layer of the cavity wall, and that wetting by poly (methyl methacrylate) is effective.
Dielectric Properties of Zinc Oxide-Eugenol Type Cements
Authors: Braden M. , Clarke R.L.
Published: November 2010

Relative permittivity and resistivity of zinc oxide-eugenol cements was measured during setting. During setting the relative permittivity goes through a very pronounced maximum; simultaneously, resistivity suddenly increases by a few orders of magnitude. Such behavior is explicable in the initial function of water, which subsequently becomes bound.
Total Viable Count of Microorganisms in the Infected Dental Pulp
Authors: Akpata E.S.
Published: November 2010

A technique for estimating the total viable count of microorganisms in the infected dental pulp is described. The count obtainable using blood agar, tomato juice agar, or Sabouraud's agar solid media is about 106 per tooth. Anaerobes are more numerous than aerobes counted on the blood agar plates. It may be possible to apply this technique for evaluating the efficacy of root canal dressings.
Chemical Prevention of Calculus Formation in the Rat
Authors: Stookey George K. , McDonald James L.
Published: November 2010

The influence of an amidopolyphosphate on calculus formation in the rat was investigated. Topical applications of the agent administered twice daily at concentrations of 2.5 and 5% resulted in a significant decrease in calculus accumulation, whereas 1% solution was ineffective.
In Vivo Plaque Measurement in the Rat
Authors: Park K.C. , Katz Simon
Published: November 2010

A method fox the in vivo measurements of plaque in the albino rat is described, in which plaque is stained with basic fuchsin and observed through an otoscope fitted with a magnifying glass. The method permits successive assessments in the same rat, and it is simple, reliable, accurate, and reproducible.
Short-Term Bond Strengths Between Adhesive Cements and Dental Alloys
Authors: Moser J.B. , Brown D.B. , Greener E.H.
Published: November 2010

The tensile bond strength between three polycarboxylate cements and Types I and III gold, 304 stainless steel, and cobalt-chrome alloy was compared to that obtained with a silico-phosphate and a zinc phosphate cement. The polycarboxylate cements showed higher strengths with almost all alloys than did the other two.
Comparison of the Retentive Property and Dentinal Crazing Ability of Retention Pins and Machinist's Taps
Authors: Kai Chiu Chan  , Svare Carl W. , Williams R.H. , Khowassah Mohamed A.
Published: November 2010

A comparison was made of the dentinal crazing formation and pull-out strength of conventional retention pins and modified machinist's taps. Modified machinist's taps produced less dentinal crazing in wet, fresh, and dried dentin than the conventional retention pins. Modified taps have sufficient pull-out strength to retain restorations on teeth with fresh dentin, in clinical situations.
A Method for the Intraoral Determination of the Cariogenicity of Foodstuffs : A Preliminary Report
Authors: Lambrou D.B.
Published: November 2010

A technique is described for testing the cariogenicity of various foodstuffs. With this method carious attack can be observed in its early and clinically undetectable stages.
Mixtures of Elastomer Impression Materials of the Same Group: II. Permanent Deformation
Authors: Kaloyannides Thanos M.
Published: November 2010

The permanent deformation of certain mixtures of elastomer impression materials of the same group was investigated. By use of these mixtures impression pastes of a consistency appropriate for every case can be produced.
Effect of Topical Applications of Neutral Sodium Fluoride on Dental Caries in the Rat
Authors: Poulsen S. , Larson R.H.
Published: November 2010

A study on various regimens by which the same total amount of neutral sodium fluoride is applied to the teeth of rats showed that greater effects were observed after frequent application of 0.2% solutions than after less frequent application of more concentrated solutions.
Arteriosclerotic Changes within the Diabetic Oral Vasculature
Authors: Keene Joseph J.
Published: November 2010

Microscopic sections of diabetic, arteriosclerotic nondiabetic, and nondiabetic nonarteriosclerotic human palate were qualitatively evaluated for small artery colloidal-iron-positive, acid mucopolysaccharide content. The association of abnormal colloidal-iron-positive material with structural detail in the arterial wall was clarified by comparison with specimens of amputated diabetic human legs.
Postdevelopmental Effects of Boron, Fluoride, and Their Combination on Dental Caries Activity in the Rat
Authors: Liu F.T.Y.
Published: November 2010

Drinking water of rats aged 21 days was supplemented with 1, 10, 30, 50, 100, or 283 ppm of boron or 10 or 25 ppm of fluoride individually or in combination. All rats were fed a cariogenic diet. Boron did not reduce dental caries activity in erupted molars after eight weeks. When given in combination, it partially antagonized the cariostatic effect of fluoride.
Effect of Conditioning with Fluoride and Phosphoric Acid on Enamel Surfaces as Evaluated by Scanning Electron Microscopy and Fluoride Incorporation
Authors: Kochavi David , Gedalia Itzhak , Anaise Joseph
Published: November 2010

The etching effect of 50% H3PO4 applied together with 2% NaF or SnF2 was compared with the effect of H3PO4 on pre- and postfluoridated enamel by scanning electron microscopy. Substantial etching of enamel resulted with use of 50% H3PO4 with 2% NaF. High fluoride incorporation in the surface provided additional protection of the conditioned enamel.
Effect of Sugar Analogues on Growth, Sugar Utilization, and Acid Production by Streptococcus mutans
Authors: Schachtele Charles F. , Leung Woon-Lam S.
Published: November 2010

Studies on the effect of various structural analogues of glucose of phosphoenolpyruvate (PEP)-dependent sugar transport in Streptococcus mutans showed that sugars with alterations at carbon 2 were markedly inhibitory. Low concentrations of the non-fermentable analogue D -2-deoxyglucose (2-deoxyG) blocked the growth of S mutans in broth media containing various fermentable sugars. Acid production by S mutans from. both exogenous glucose and intracellular storage polysaccharide was inhibited by 2-deoxyG. The analogue is bacteriostatic, and large quantities of intracellular 2-deoxyG-6-PO4 accumulate during exposure of S mutans to the sugar.
Herpes Simplex Virus Type 1 Replication in a Gingival Cell Line
Authors: Fletcher R.D. , Guggenheimer J. , Sumney D. , Platt D.
Published: November 2010

Propagation of herpes simplex virus type 1 (HSV-1) in gingival cells is advantageous since these cells are more definitive than HeLa cells in demonstrating viral-induced cytopathic effects and are easily and economically maintained in the laboratory. They also provide a potential medium for studying oral tissue reactions to HSV-1 infection. HSV-1-induced cytopathic effects are clearly characterized following inoculation with virus from standard laboratory cultures and human infections.
Surgical Method for Exteriorizing the Orifice of Stensen's Duct for Long-Term Collection of Parotid Saliva
Authors: Tamarin Arnold , Smith Orville A.
Published: November 2010

A surgical method is described for exteriorizing the orifice of Stensen's duct in non-human primates. This operation is useful in experiments entailing the collection of parotid saliva on a continuous long-term basis. Histological evidence demonstrates a complete competent union between mucosa and skin at the site of surgery.
Radioactive Labeling of Proteins with an Iodinated Amidination Reagent
Authors: Wood Frederick T.
Published: November 2010

An iodinated phenolic imidoester has been synthesized for the labeling of proteins to high specific activities with radioactive iodine. The main advantage of this two-step labeling method is that it obviates direct contact of the protein with deleterious oxidizing agents, such as chloramine-T, pressent in direct methods of iodinating proteins.
Staining Reaction of Dental Plaque After Various Extraction Procedures
Authors: Christie T.M. , Lacy R. , Newbrun E.
Published: November 2010

After water and dilute alkali extraction, a sample of dental plaque that was stained by the PA-CrA-silver technique showed staining intracellularly on the cell wall and extracellularly. When more prolonged and stronger alkali extraction was used, reacting material was retained on the cell wall and intracellularly. There was a noticeable loss of extracellular reacting material.
Multiple Regression of Predictors and Criteria of Dental School Performance
Authors: Houston John B. , Mensh Ivan N.
Published: November 2010

This study reports normative data for 370 students admitted to the UCLA School of Dentistry, data on commonly used performance predictors, and the regression equation best fitted for forecasting performance in this school. Most variance was associated with dental school grade point average, National Board Dental Examination averages, and clinical performance. Best predictors were achievement level and trend in preadmission academic performance. The selection interview and high school performance were also evaluated as predictor criteria.
Origin of Cyclic Adenosine Monophosphate in Saliva
Authors: Kanamori Takao , Nagatsu Toshiharu , Matsumoto Shosei
Published: November 2010

The level of cyclic adenosine monophosphate (AMP) in duct saliva from the dog submandibular gland was increased after cyclic AMP was administered intravenously in vivo. Isoproterenol increased the level of cyclic AMP in plasma and saliva in vivo and in salivary gland slices in vitro, but increased the level only slightly in saliva in a perfused dog submaxillary gland.
Enhancement of the Antiplaque Value of Antibacterial Agents by Enamel-Conditioning Methods: I. Rationale, Mechanism, and Initial Findings
Authors: Katz Simon , Park Kichuel
Published: November 2010

A method is proposed to induce chemically the incorporation of bacterial agents into enamel and thus render this tissue resistant to bacterial colonization. It consists of promoting a slight initial dissolution of enamel, followed immediately by its reprecipitation. During this latter phase, antibacterial agents included in the test formulations would become trapped in the reprecipitating enamel. That this happens is proved by the chemical detection of antibacterial agents in treated enamel, as well as by the development of a remarkable resistance of treated specimens to grow in vitro plaque.
Model Practice as a Valid Research Tool for Studying Actual Private Practice
Authors: Chadwick D.G.
Published: November 2010

Data from the actual private practices of two dentists were compared with respective data from the participation of the same two dentists in a laboratory model of private practice conducted in the University of North Carolina Dental Research Center. The findings show that a laboratory model can be established which accurately reflects the major parameters of an actual private practice.
Histological Response to Ivory Implanted in Rabbit Mandibles
Authors: Ceravolo F.J. , Molinari J.A. , Baumhammers A.
Published: November 2010

Ivory rod implants were found to be biologically unacceptable in rabbit mandibles. Fibrous connective-tissue capsules containing numerous multinucleated giant cells formed around the implants. Resorption of the ivory was also apparent. In addition, osteoid deposition and ankylosis at the experimental sites were not evident.
Acidogenic Potential of Cariogenic and Noncariogenic Diets in the Rat
Authors: Steinman Ralph R. , Leonora John
Published: November 2010

No significant difference in lactic acid content was observed in food residues removed from the occlusal grooves of rats receiving Purina lab chow or the 62% sucrose cariogenic diet. The incubation of rat saliva with Purina chow, with 62% sucrose diet, or with the 62% sucrose diet supplemented with carbamyl phosphate, egg shell meal, and the trace elements zinc, molybdenum, and chromium produced in 24 hours essentially the same pH curve. The terminal titratable acidity observed in saliva incubated with the 62% unsupplemented diet, however, was significantly less than that produced in salivary mixtures containing either Purina chow or supplemented sucrose diets.
Effect of Radiation-Induced Xerostomia on Human Oral Microflora
Authors: Brown Lee R. , Dreizen Samuel , Handler Sandra , Johnston Dennis A.
Published: November 2010

A longitudinal study was performed to assess the effects of radiation-induced xerostomia on the human oral microflora. Pronounced microbial population shifts were found in each of five intraoral sites tested. Cariogenic microorganisms gained prominence at the expense of noncariogenic microorganisms in concert with the saliva shutdown. These changes occurred before the onset of clinical caries irrespective of whether or not a topical fluoride gel was used as a caries preventive.
Effect of Humidity and Temperature Changes on Orthodontic Direct-Bonding Adhesive Systems
Authors: Bishara Samir E. , Khowassah Mohamed A. , Oesterle Larry J.
Published: November 2010

Plastic brackets were bonded to 560 extracted human teeth with use of two orthodontic adhesive systems: (1) methyl methacrylate resin bonded to a sealant that was polymerized using ultraviolet light, and (2) self-polymerizing methyl methacrylate resin bonded directly to the etched enamel. Tensile and shearlike tests were performed. Prolonged exposure to heat, moisture, and severe temperature changes decreased the shearlike strength of both adhesives. Both systems were adequately strong to withstand routine orthodontic and estimated masticatory forces.
SNA and SNB Angles in a Population of Nubian Schoolchildren
Authors: Walker Susan J. , Harris James E. , Kowalski Charles J.
Published: November 2010

The descriptive statistics for the sella-nasion-A Point (SNA) and sella-nasion-B point (SNB) angles computed from a sample of Nubian schoolchildren are presented, by age and sex, and compared with the analogous statistics for American Caucasian schoolchildren .
Polymerizable Amines as Promoters of Cold-Curing Resins and Composites
Authors: Dneboský J. , Hynková V. , Hrabák F.
Published: November 2010

The accelerating activity of N,N-substituted aminoethyl methacrylates on the curing of methyl methacrylate and composite resins with benzoyl peroxide is somewhat smaller than that of dimethyl-p -toluidine. Resins cured with aminoethyl methacrylates containing a p-tolyl and 3,5-xylyl substituent on the nitrogen atom turned approximately the same color in ultraviolet light as resins cured with dimethyl-p-toluidine. The incorporation of the predominant part of an unsaturated tertiary amine into polymer chains reduces to a minimum the possibility of its diffusion from the resin into the surrounding tissue.
Effect of α, α'-Dipyridyl on the Basement Membrane of Tooth Germs In Vitro
Authors: Hetem Sebastiao , Kollar Edward J. , Cutler Leslie S. , Yaeger James A.
Published: November 2010

Dipyridyl inhibits the morphogenesis of tooth germs, but the germs recover when transferred to control medium. In this study, the effect of dipyridyl on basement membrane was investigated in vitro. The basal lamina was always present, but the subjacent collagen fibrils disappeared in the presence of dipyridyl and reappeared during recovery in control medium.
Reproducibility of the Electromyogram
Authors: Garnick Jerry J.
Published: November 2010

Electromyographic recordings of masseter muscles were taken during mastication without the introduction of an experimental variable. The amplitude, duration, and sequence of the onset of muscle bursts were used to evaluate the recordings. Amplitude showed the most variation during the same session, at different sessions, and between three different areas of the masseter muscle. Onset showed the least variation during the same session and at different sessions; duration showed the least variation between areas.
Role of Attrition and Occlusal Contact in the Physiology of the Rat Incisor: IX. Impeded and Unimpeded Eruption in Lathyritic Rats
Authors: Michaeli Y. , Pitaru S. , Zajicek G. , Weinreb M.M.
Published: November 2010

In the rat, the administration of a lathyrogenic agent reduced both impeded and unimpeded eruption rates of incisors. Unimpeded eruption rates were greater than impeded eruption rates. The general eruption pattern in the experimental rats was, however, similar to that in the control rats. Thus, eruption was possible even in rats with a lathyrogenically impaired periodontal ligament.
Effects of Single Exposure to Sugar on Calcium and Phosphorus Concentrations of Dental Plaque
Authors: Ashley F.P.
Published: November 2010

The results from three studies on the plaque of children and adults indicated that the response of the plaque to a single five-minute exposure to sugar cubes or boiled sweets (candies) depended on the initial condition of the plaque. Thus, significant decreases in the levels of calcium and phosphorus in plague were observed in previously starved plaques but not in Plaque from participants without previous dietary sugar restriction.
Glycoprotein Biosynthesis at the Time of Palate Fusion by Rabbit Palate and Maxilla Cultured In Vitro
Authors: DePaola Dominick P. , Drummond James F. , Lorente Carol , Zarbo Richard , Miller Sanford A.
Published: November 2010

The dynamics of glycoprotein biosynthesis in rabbit maxillary and palatal explants at the time of palatal fusion was studied using3H -fucose and 14C-leucine as precursors. The results show that there is an increase in glycoprotein biosynthesis in the rabbit palate in vitro at a time commensurate with the onset of contact and adherence of the palatal shelves.
Effects of Short-Term and Long-Term Administration of Procaine Hydrochloride and Mepivacaine Hydrochloride on Hexobarbital-Induced Sleeping Times in Mice
Authors: Rinchuse Daniel J. , Smudski James W.
Published: November 2010

Investigations were performed to determine the effects of short-and long-term pretreatment with procaine and mepivacaine on hexobarbital-induced sleeping times in mice. It was found that short-term preadministration with procaine (40 mg/kg) and mepivacine (40 and 60 mg/kg) significantly increased hexobarbital-induced sleeping time, but long-term pretreatment had no effect.
Biochemical and Morphological Studies of Rat Submandibular Gland: I. Centrifugal Fractionation of Granule-Rich Fraction
Authors: Hanks C.T. , Chakrabarti S.G.
Published: November 2010

Submandibular glands from male rats were homogenized in 0.34 M sucrose and 0.5 mM ethylenediaminetetraacetic acid in 10 mM HEPES buffer at a pH of 7.4. The extract was centrifuged and filtered through nuclepore filters to prepare a granule-rich fraction. Electron dense zymogen granules constituted approximately 85% of the particles in this fraction which also contained about a third of the total alkaline esterase activity in the gland.
Biochemical and Morphological Studies of Rat Submandibular Gland: II. Partial Purification of Proteins from Granule-Rich Fraction
Authors: Chakrabarti S.G. , Hanks C.T. , Johnson S.P.
Published: November 2010

Soluble proteins derived from a centrifuged and filtered granule-rich fraction of homogenized rat submandibular gland were analyzed by gel filtration, ion-exchange chromatography, and polyacrylamide gel electrophoresis. Both the granule-rich fraction and final supernatant fraction contained alkaline esterase activity. The major protein component, derived from granules of the convoluted tubules, was further resolved into a series of peptides ranging in molecular weight from 9,000 to 55,000 daltons.
Effect of Toothbrush Variables on Wear of Dentin Produced by Four Abrasives
Authors: Harte D.B. , Manly R.S.
Published: November 2010

A study was conducted to explore the effect of brush brand, brush hardness, and the concentration of abrasive on the wear of human dentin by four dentifrice abrasives. The two hard brushes produced similar and high levels of abrasion, whereas the two medium brushes of the same brands gave dissimilar and lower levels of abrasion. Dilution changed the ranking of two of the four abrasives.
Adhesive Penetration in Human Artificial and Natural White Spots
Authors: Dayila Jorge M. , Buonocore Michael G. , Greeley Constance B. , Provenza D. Vincent
Published: November 2010

Penetration of a liquid adhesive into human artificial and natural white spots, both acid-conditioned and nonconditioned, was studied. All artificial white spots showed penetration of the adhesive. Acid-conditioned natural lesions exhibited penetration to a lesser amount than in vitro lesions. Penetration in nonconditioned natural lesions was not apparent.
In Vitro Wear Response of Composite Resin, Amalgam, and Enamel
Authors: Powell Joseph M. , Phillips Ralph W. , Norman Richard D.
Published: November 2010

A two-body, wear-testing method was developed and the test results were used for comparing and ranking the rate of wear for an amalgam, an experimental composite resin, and a commercial composite resin. The ranking of wear found by this method was the same as that shown by clinical research for the rate of wear of amalgam and commercial composite resin.
Compressive Viscoelastic Properties of Human Dentin : I. Stress-Relaxation Behavior
Authors: Duncanson Manville G. , Korostoff Edward
Published: November 2010

Stress-relaxation measurements were performed on specimens of radicular human dentin. The relaxation modulus showed a linear dependence on the logarithm of time and the approximation to the logarithmic distribution function of relaxation times was used to predict the behavior of other viscoelastic properties. This experimental technique provides significant criteria for the design of polymeric restorative and prosthetic materials.
Quantitative Stereological Investigations of Porous Alumina Implant Biomaterials
Authors: Lemons J.E. , Richardson W.C.
Published: November 2010

Quantitative stereological measurements of porous alumina dental implant materials included intercepts in length, points occupied, number in area, mean lineal intercept, volume fraction, and surface area in volume. A pore-solid network analysis from 81 serial sections showed variable pore dimensions and geometry and a completely interconnected major pore network.
Effects of Cement Bases on the Stresses and Deflections in Composite Restorations
Authors: Farah J.W. , Powers J.M. , Dennison J.B. , Craig R.G. , Spencer J.
Published: November 2010

A model was used to show that tensile and shear stresses can occur in sufficient magnitude to cause failure in a cement base supporting a composite material in a posterior Class I restoration. Highest values of stress were observed when lining materials with a low modulus were used.
Development of Scales to Measure Provider Attitudes Toward Expanded Duty Dental Auxiliaries
Authors: Berger Phillip K. , Domer Larry R. , Cooper Thomas M.
Published: November 2010

Factor analysis was used to define four independent dimensions of the larger construct ; attitudes toward the utilization of expanded duty dental auxiliaries and scales were developed to measure each dimension. Examination of differences in attitudes between and within dental provider groups showed that with one exception there was no discernible pattern of differences between these groups.
A Physicochemical Approach to the Study of Amines as Antiplaque Agents
Authors: Warner Victor D. , Warner Ann M. , Mirth Dale B. , Sane Jayant N. , Turesky Samuel S. , Soloway Barbara
Published: November 2010

Alkyl and aromatic amines and their salts were evaluated for inhibitory activity against Streptococcus mutans 6715. Antiplaque activity was correlated with the physicochemical properties, lipophilicity and basicity. The results indicate that the basicity of the amine is the primary requirement for activity. The lipophilic character then exerts a modulating effect on amines with the proper pKa values.
In Vitro Interactions Between the Surfaces of Enamel White Spots and Calcifying Solutions
Authors: Wei Stephen H.Y. , Wefel James S.
Published: November 2010

The morphological appearance of white spot enamel after treatment with various calcium phosphate and sodium fluoride solutions was examined using the scanning electron microscope. The reaction products formed after the sequential application of the calcifying solutions and a high concentration of fluoride appeared to fill in the porosity created in the enamel surface by white spot formation.
Production of Plaques and Initiation of Caries in Vitro
Authors: Yaari A. , Bibby B.G.
Published: November 2010

An in vitro method that uses thawing frozen saliva offers an improved way for studying the interactions of food and other factors in the initiation of caries.
Dentin Formation in Periodontally Diseased Teeth
Authors: Lantelme Rudolph L. , Handelman Stanley L. , Herbison Richard J.
Published: November 2010

Pulp canals of periodontally healthy and periodontally diseased upper anterior teeth were measured at the "apex," "middle," and "crown end." Teeth were further categorized by age. When mean differences were compared, there was a narrowing of the pulp canal diameters at every morphological level for periodontally diseased teeth. As anticipated, there was also a narrowing of the pulp canal with age.
Characteristics of an In Vitro Dental Pellicle
Authors: Stiefel Doris J.
Published: November 2010

Dental pellicle was formed in vitro after two-hour incubation of extracted human molars in parotid saliva. Control teeth were incubated in distilled water. Electropherograms of proteins subsequently eluted from the teeth indicated selective salivary adsorption and desorption. In addition, extra-salivary pellicle constituents, comprising albumin and alkaline phosphatase, were identified.
Acrylamide Gel Electrophoretic Studies of Extracellular Sucrose-Metabolizing Enzymes of Streptococcus mutans
Authors: Osborne R.M. , Lamberts B.L. , Meyer T.S. , Roush A.H.
Published: November 2010

Acrylamide gel electrophoretic methods were used to assess the numbers and types of sucrose-metabolizing enzymes elaborated by Streptococcus mutans strains HS-6, SL-1, FA-1, and NCTC 10449. Two types of polysaccharide-synthesizing enzymes and one invertaselike enzyme were distinguished. The patterns of extracellular proteins and enzymes were distinctive for each strain.
Evaluation of Instructional Materials for Teaching Psychomotor Skills
Authors: Gale Marc A. , Koran Mary Lou , Grainger David A. , Watson Ronald E.
Published: November 2010

An investigation was conducted to determine the effectiveness of self-instructional materials for a cavity preparation procedure using two types of dental auxiliaries under assisted and unassisted instructional conditions. Results showed significant pretest to posttest performance gains, with the instruction proving equally effective across both types of auxiliaries and instructional conditions.
Studies of the Mechanism of Sucrose-Associated Colonization of Streptococcus mutans on Teeth of Conventional Rats
Authors: Van Houte J. , Upeslacis V.N.
Published: November 2010

Firm attachment of S mutans cells to teeth by means of extracellular glucans synthesized from sucrose that lead to colonization in vivo may proceed via two mechanisms: (1) directly, via preformed glucans associated with the cell or the teeth or both, or (2) via new glucan synthesis by cells that are initially weakly attached, irrespective of the presence of cell- or tooth-surface-associated glucans. Data from experiments with conventional rats suggest that new glucan synthesis is the principal attachment mechanism.
Experimental Carcinogenesis in Duct-Artery Ligated Rat Submandibular Gland
Authors: Englander Abraham , Cataldo Edmund
Published: November 2010

This study compared tumor induction time and the type of tumor formed in rat submandibular glands implanted with 9,10-dimethyl-1,2-benzanthracene (DMBA) to glands ligated before implantation of DMBA. Results showed no difference in tumor induction time or the type of tumor formed.
Influence of Amalgam, Alloy, and Mercury on the in Vitro Growth of Streptococcus mutans: I. Biological Test System
Authors: Nunez Loys J. , Schmalz Gottfried , Hembree John
Published: November 2010

A procedure is presented for the in vitro growth of Streptococcus mutans in a dextrose-beef extract medium. Growth was estimated spectrophotometrically. The amount of amalgam, alloy, or mercury that was added to the sealed test tube influenced the rate and extent of growth.
Potential Use of One-Phase Poly(methyl methacrylate) in Dental Implants
Authors: Zaki Hussein S. , Kamel Ihab L.
Published: November 2010

Through compounding and molding techniques, variation of porosity and the resulting effect on the mechanical properties of one-phase poly(methyl methacrylate) (PMMA) were studied. Characterization of the composites developed was pursued by correlating the microstructure with the physical and mechanical behavior of the material. From the three compounding techniques studied, NaCl-filled PMMA proved to have the best overall mechanical properties and control of porosity compared to a wide range of filler content.
Electron Microscope Comparison of Freeze-Substitution and Conventional Chemical Fixation of Undecalificied Human Dentin
Authors: Hicks Morris Lamar , Brilliant J. David , Foreman D.W.
Published: November 2010

Undecalcified human dentin was prepared for electron microscopy by conventional chemical fixation with alcoholic dehydration and by freeze-substitution with cryodehydration. Comparisons are reported concerning effects of different preparation methods. Morphology remained unaltered in the pre-dentin and mineralized matrices. The technique comparison permitted inferences regarding hydration states and relative amounts of protein in different areas of the odontoblast cell.
Adhesion of Orthodontic Cements to Human Enamel
Authors: Moser J.B. , Dowling D.B. , Greener E.H. , Marshall G.W.
Published: November 2010

Tensile bond strengths between five orthodontic cements and acid-etched enamel were studied. The influence of a saline primer and storage in artificial saliva at 37 C for up to 30 days was evaluated. Statistically significant differences were found for different cements, time of storage, and the effect of silane pretreatment on etched enamel.
Selection of an Experimental Unit in Rat Caries Studies
Authors: Briner William W.
Published: November 2010

Fourteen subunits including quadrants and molars were compared in two rat caries studies with the individual rat as the standard unit. None of the subunits consistently ranked treatments similarly to the standard unit. Arbitrarily dividing the rat into subunits may lead to false conclusions since the rankings using subunits vary.
Reactions in Glass-Ionomer Cements: IV. Effect of Chelating Comonomers on Setting Behavior
Authors: Wilson A.D. , Crisp S. , Ferner A.J.
Published: November 2010

The effect of the addition of chelating comonomers, to the polyacid liquids, on the setting characteristics of the glass-ionomer cement system is described. Certain acid chelating agents significantly improve the setting behavior of the system.
Kinetics and Mechanism of Hydroxyapatite Crystal Dissolution in Weak Acid Buffers Using the Rotating Disk Method
Authors: Wu Maw-Sheng , Higuchi William I. , Fox Jeffrey L. , Friedman Michael
Published: November 2010

The dissolution rates of synthetic hydroxyapatite pellets under sink conditions were measured using the rotating disk method. The experimental data were analyzed by means of a physical model that yielded an ionic activity product of KHAP = a10 Ca2+ a6 PO4 3- a2OH- = 1 × 10-124.5±1.0 that was found to govern the dissolution reaction. Also, a surface resistance factor of k' equal to about 174 sec/cm was deduced from the data.
Susceptibility of Some Plaque Microorganisms to Chemotherapeutic Agents
Authors: Newbrun Ernest , Felton Richard A. , Bulkacz Jaime
Published: November 2010

Several drugs were evaluated for their optimal effective concentrations against specific odontopathic organisms. The minimal inhibitory concentrations for niddamycin, vancomycin, and bacitracin ranged from 0.2 to 10 units/ml. Kanamycin was inhibitory at much higher concentrations (130 to 500 units/ml).
Epithelial Cells Associated with the Development of Dental Plaque
Authors: Tinanoff Norman , Gross Arthur
Published: November 2010

Electron microscopy was used to study desquamated epithelial cells in developing and mature dental plaques. Epithelial cells were commonly found in early plaque, and they may affect the adherence of bacteria onto teeth. The cells adsorbed to the enamel seem to undergo morphologic alterations.
Effect of Premature Loss of Deciduous Canines and Molars on Malocclusion of the Permanent Dentition
Authors: Miyamoto W. , Chung C.S. , Yee P.K.
Published: November 2010

There was a significantly increased frequency of orthodontic treatment among those with the premature loss of one or more deciduous teeth. Of those with no history of orthodontic treatment, there was a significant effect of the premature loss of molars but not canines on malalignment. Anterior crowding was related only to the premature extraction of canines.
Surface and Lamina Propria Lipids of Bovine Gingiva
Authors: Das S.K. , Adhikary P.K. , Bhattacharyya D.K.
Published: November 2010

Lipids of the surface and lamina propria of bovine gingiva are characterized and compared. Most of the lipids are contained in the lamina propria. The most prominent surface lipids are cholesterol, cholesterol esters, and phospholipids as compared with the typical storage triglycerides of the deeper layers.
Characterization and Modification of Permselective Properties of Apatite Membranes
Authors: Tung M. S.
Published: November 2010

Compressed apatite disks were used as models for tooth enamel. Their permselective properties were studied as functions of the pH of the gradient solutions, the composition of the apatites, and the pretreatments with anionic phosphate compounds and cationic proteins. The results are discussed in relation to the caries mechanisms.
Seeded Growth of Calcium Phosphates: Effect of Different Calcium Phosphate Seed Material
Authors: Nancollas G.H. , Wefel J.S.
Published: November 2010

The growth of calcium phosphates on seed materials, dicalcium PhosPhate dihydrate (DCPD), tricalcium phosphate (TCP), octacalcium phosphate (OCP), and hydroxyapatite (HAP) in stable supersaturated solutions has been studied under conditions of pH and concentration for which the predominant phases are 1, DCPD, and II, HAP. All seed crystals are good nucleators for DCPD in system I, but, aside from HAP itself, only OCP will readily induce growth under condition II.
Xylitol-Induced Increase of Lactoperoxidase Activity
Authors: Mäkinen K.K. , Tenovuo J. , Scheinin A.
Published: November 2010

Persons who were fed a strict diet with regard to the type of sweeteners used (sucrose, fructose, and xylitol) displayed differences in salivary peroxidase activity. Xylitol consumption considerably increased the salivary lactoperoxidase activity. Persons habitually consuming a xylitol-containing diet may avoid certain oral inflammatory processes because of the antibacterial properties of the enzyme.
Effect of Salivary Pellicle on Enamel Subsurface Demineralization In Vitro
Authors: Zahradnik R.T. , Moreno E.C. , Burke E.J.
Published: November 2010

Diffusion fluxes of two anionic species through hydroxyapatite membranes were found to be reduced up to 50% by the presence of adsorbed salivary pellicles developed on the membrane surfaces. By contrast, water fluxes were only marginally affected, indicating that salivary pellicles display ionic permselectivity. This property is used to explain a remarkable protection of the enamel observed when salivary pellicles were developed on extracted teeth before exposure to acid lactate buffers.
Removal of Dentin by Fuchsin Staining
Authors: Sato Yuichiro , Fusayama Takao
Published: November 2010

When tested in vitro and in vivo, the removal of all dentin stainable by the 0.5% basic fuchsin-propylene glycol solution method assured complete removal of infected carious dentin. The image on the radiograph was always somewhat narrower than the extent of the fuchsin-stainable dentin to be removed.
Semiporous Reinforcing Fillers for Composite Resins: I. Preparation of Provisional Glass Formulations
Authors: Bowen R.L. , Reed L.E.
Published: November 2010

A conceptual means of obtaining improved bonding between filler particles and the polymeric binders of composites is presented. It involves preparing glass particles that separate into two interconnected vitreous phases when heated to an appropriate temperature, and then etching these to produce a porous surface layer. Candidate glass compositions were prepared and subjected to heat treatment in a gradient furnace. Compositions susceptible to phase separations were delineated.
Stress Analysis of Porous Rooted Dental Implants
Authors: Weinstein Allan M. , Klawitter Jerome J. , Anand Subhash C. , Schuessler Richard
Published: November 2010

A two-dimensional plane stress finite element analysis of porous rooted dental implants was performed. The results of this analysis were compared to results obtained from mechanical tests performed on actual implanted specimens. The appropriate selection of interface material properties was shown to be highly significant.
Periodontal Disease Among Children with Down's Syndrome and Their Siblings
Authors: Orner G.
Published: November 2010

The prevalence and severity of periodontal disease were determined by the Periodontal Index of Russell in 212 individuals with Down's syndrome and 124 of their unaffected siblings. Both prevalence and severity of the disease were greatest in the individuals with Down's syndrome whereas the siblings demonstrated an experience not unlike that of the US population of children.
Composition of Fluoridated Dental Enamel Studied by X-ray Photoelectron Spectroscopy (ESCA)
Authors: Hercules David M. , Craig Norman L.
Published: November 2010

Enamel surfaces that had been treated with an acid phosphate-fluoride gel were analyzed for phosphorus, calcium, fluorine, and carbon using X-ray photoelectron spectroscopy. This technique revealed a heavy carbon coating on the enamel that overlays a surface composed of a 1:2 ratio of calcium to fluorine. Evidence is presented for a noncaL cium phosphorus species in the surface layer. Removal of successive layers of enamel by argon-ion etching showed a steady decrease in fluorine and a corresponding increase in phosphorus concentrations.
Kinetics of Calcium Metabolism in Rat Dentin and Enamel
Authors: Tumilasci Omar R. , Alonso Guillermo L.
Published: November 2010

The time course of the specific activity of 45Ca in the dentin and enamel of rat incisors and molars was followed after an intravenous injection of the radiotracer. It was then correlated with the specific activity of 45Ca in plasma to obtain the accretion rates on the dentin of molars and incisors. The exchangeable calcium pool sizes in the dentin and the enamel of the molar were also calculated.
Mandibular Condylectomy in the Guinea Pig: Quantitative Triple Fluorochrome Study
Authors: Soni Narendar N. , Malloy Randolph B.
Published: November 2010

Different-colored fluorochromes were administered sequentially to guinea pigs and the rate of bone formation measured in their condylectomized and control contralateral hemimandibles. The differences in values of condylectomized and control contralateral sides for demethylchlortetracycline- and total surface area-labeled bone were statistically signifrcant but were not significant for 2,5-bis [N-N1 -di-(Carbomethyl) aminomethyl]- and hematoporphyrin-labeled bone.
Mitotic Activity in the Oral Epithelium of the Albino Rat
Authors: Cleaton-Jones P.
Published: November 2010

In groups of Wistar rats 3 and 12 months of age, colchicine and radioautography were used to assess mitotic activity in oral epitheliums. Apparent mitotic activity in the epitheliums of the cheek, hard palate, and central, intermediate, and lateral zones of the soft palate depended on the method used and the age of the rat.
Developmental Changes of Calcium-Stimulated Adenosine Triphosphatase in Rat Submandibular Gland
Authors: Furuyama Shunsuke , Son Yoshimitsu , Ogawa Hitoshi , Matsubayashi Hiroo , Takiguchi Hisashi
Published: November 2010

Developmental changes of Ca2+-stimulated adenosine triphosphatase (ATPase) in rat submandibular glands were determined in the fetus and up to 300-day-old rats, and were discussed in relation to the development of salivary gland functions.
Glucose Taste Thresholds in Cariesfree Naval Recruits
Authors: Mickel G.J. , Catalanotto F.A. , Keene H.J.
Published: November 2010

Glucose taste detection thresholds were determined in 41 cariesfree recruits and 53 recruits with caries experience. Cariesfree detection thresholds ranged from 5 to 45 mM/ liter, with a mean of 13.4 ± 1.7 whereas that of the control group ranged from 5 to 50 mM/ liter with a mean of 22.3 ± 1.7 (P < 0.01). A Kilmogorov-Smirnov two-sample test demonstrated a significant difference in the distribution of thresholds between the two groups (P < 0.01). These observations are in accordance with previous studies demonstrating that cariesfree recruits display lower sucrose taste detection thresholds than recruits with caries experience.
Sequential Quantitative Radionuclide Evaluation of Mandibular Bone Graft Repair
Authors: Kelly James F. , Cagle John D. , Adler Gary J. , Donovan Richard L.
Published: November 2010

This article describes a noninvasive method to derive quantitative radionuclide data from images of grafted dog mandibles including localizaton of the graft in sequential radionuclide images. The method permits comparison of bone repair activity between experimental subjects and also between selected zones within individual bones, thus objectively defining the pattern of repair.
Examiner Standardization for Caries Studies
Authors: Fischman Stuart , Picozzi Anthony , Juliano Daniel , Slakter Malcolm , English James
Published: November 2010

Examiners in clinical control programs customarily undergo an intensive period of training to standardize their interpretation of diagnostic criteria. Data are presented summarizing examiner error rates in calibration examinations and reversal rates in a field study.
Ion Probe Study of Fluorine Gradients in Outermost Layers of Human Enamel
Authors: Petersson L.G. , Odelius H. , Lodding A. , Larsson S.J. , Frostell G.
Published: November 2010

F concentrations in the outermost layers of human tooth enamel were studied with the aid of a secondary ion microanalyzer. Concentration profiles were recorded in continuous sputtering analysis from the surface down to a depth of about 0.3 micrometer. Samples previously subjected to topical fluoride treatment were compared with reference specimens. In some samples, the results were compared with those obtained at greater depths by macrascopic etching analysis.
Dental Plaque and Dietary Intakes in Schoolchildren in Hawaii
Authors: Chung C.S. , Hankin J.H. , Miyamoto W. , Kau M.C.
Published: November 2010

The level of dental plaque as measured by surface area increased with the higher consumption of sucrose-containing sticky food such as sweet rolls, sweet breads, manapua, mochi, or poi. Consumption of fruit drinks was associated with less plaque formation. The plaque score had little relationship to the DMF index, whereas it showed a significant association with periodontal disease.
Influence of the Topical Application of Fluoride on the in Vitro Adhesion of Fissure Sealants
Authors: Low T. , Von Fraunhofer J.A. , Winter G.B.
Published: November 2010

The adhesion of four polymeric sealant materials to enamel treated with a topical application of fluoride has been assessed by tensile bond strength tests. The ultraviolet light-activated resin, Nuva Seal, was found to bond adequately to stannous fluoride-treated teeth. The tensile bond strength of Espe 71730, Alpha Seal, and Epoxylite 9075 to enamel was reduced by treatment of the enamel with stannous fluoride. Treatment of the etched enamel with acidulated phosphate fluoride reduced the bond strength of all four fissure sealants.
Comparison of Gingival Health and Gingival Crevicular Fluid Flow in Children With and Without Diabetes
Authors: Ringelberg M.L. , Dixon D.O. , Francis A.O. , Plummer R.W.
Published: November 2010

A gingival crevicular fluid (GCF) flow meter was used to measure the GCF flow rate in 56 children with diabetes and 41 children without diabetes. The GCF readings were compared with clinical scores of gingival disease for the same teeth. The children with diabetes had significantly more gingival inflammation than the children without diabetes.
Color of Gingival Tissues of Blacks and Whites
Authors: Powers John M. , Capp Jacqueline A. , Koran Andrew
Published: November 2010

Value, chroma, and hue of attached gingiva of blacks and whites were measured clinically with Munsell color tabs. The color of nonmottled gingiva of blacks and whites was similar. The color of gingiva pigmented by melanin in blacks was similar in hue, but lower in value and chroma than nonmottled gingiva.
Competitive Binding Among Oral Streptococci to Hydroxyapatite
Authors: Liljemark W.F. , Schauer S.V.
Published: November 2010

The relative affinity of various oral streptococci for hydroxyapatite (HA) differed widely. Streptococcus mutans affinity for dextran-coated HA was the highest of all the streptococci to any HA coating. S salivarius had the lowest affinity, and S sanguis affinity was higher than S miteor for saliva-coated HA. Competition for binding sites on saliva-coated, dextran-coated, and saliva-dextran-coated HA among these streptococci was not observed in any pair of these bacteria on any HA coating except for that of S miteor and S sanguis to saliva-coated HA. However, competition between this pair was not for the same binding site but for closely associated sites.