bluuebunny/crossref_metadata_2025 huggingface dataset:
Behaviorally Based Measures for Evaluating the Nonclinical Performance of Dentists in Team Settings
Authors: Wallace Marc J. , Berger Philip K. , Domer Larry , Cooper Thomas M.
Published: November 2010

Retranslations of expectations technique was used to develop behaviorally anchored scales for evaluating dentists' utilization of expanded duty dental auxiliaries. To enhance the reliability and validity of such instruments the project focused on specific acts and decisions of the dentist which are either effective or ineffective in accomplishing the health team's tasks.
Bacterial Conditions of Water in Dental Units
Authors: Thé S.D. , Van't Hof M.A.
Published: November 2010

Stagnant water in the boiler of a dental unit can cause a high bacterial density. A spiral unit is somewhat superior to a boiler in this respect, Normal unchlorinated tapwater is the main problem in achieving hygienic conditions in dental practice. The technical performance of the unit is only partly responsible for the water quality.
Reduction in Dentin Wear Resistance by Irradiation and Effects of Storage in Aqueous Media
Authors: Davis W.B.
Published: November 2010

Electromechanical dentin abrasion measurements showed that the irradiation treatment applied before radio tracer dentin abrasion measurements reduced the wear resistance of dentin. This caused changes in the measured relative abrasitivities of dentifrices. Effects of storage in aqueous media were also investigated.
Inhibitory Effect of Apernyl on Production of Bradykininlike Substance in Pulp
Authors: Kudo Teruo , Kawagoe Masataka , Hayashi Takeshi , Takezawa Jun , Inoki Reizo
Published: November 2010

In the Formalin-induced pulpitis of rats and the electrically stimulated pulps of dogs, a bradykinin like substance developed by the pulps and released into a saline pool on the exposed pulps disappeared after a local application of Apernyl solution. This suggests that the possible pain-reducing or anti-inflammatory effect of Apernyl is a result of its inhibiting bradykinin production.
Composition and Mechanical Properties of Gutta-Percha Endodontic Points
Authors: Friedman Charles M. , Sandrik James L. , Heuer Michael A. , Rapp Gustav W.
Published: November 2010

Gutta-percha endodontic filling points were found to contain approximately 20% gutta-percha (matrix), 66% zinc oxide (filler), 11% heavy metal sulfates (radiopacifier), and 3% waxes and/or resins (plasticizer). The mechanical properties were indicative of a partially crystalline viscoelastic polymerfc material. They were found to obey Hooke's law and displayed a prominent upper and lower yield point when stressed beyond the proportional limit. The essential differences in mechanical properties of individual brands were found to be a function of the gutta-percha and zinc oxide concentration.
Histology of Fissures in Human Unerupted Teeth
Authors: Galil K.A. , Gwinnett A.J.
Published: November 2010

An investigation into the contents of the fissures of unerupted teeth was made using light and scanning electron microscopy techniques. For the study, 193 unerupted teeth were used. The presence of ameloblasts in the fissures was substantiated, and their role in forming the fissure is discussed.
Natural Desensitization of Exposed Tooth Roots in Dogs
Authors: Karlsson Ulf L. , Penney Deborah A.
Published: November 2010

With scanning electron microscopy, electron microprobe elemental analysis, and an objective method for eliciting responses to electrical stimuli, exposed tooth root surfaces in dogs were found to become naturally desensitized with time, perhaps because of the formation of acquired pellicle.
Effect of Dietary Supplementation of Glycine on Caries Development and Lipids in Rat Molars
Authors: Das Salil K. , Harris Robert S.
Published: November 2010

The effect of dietary supplementation of glycine at a level of 4% on caries development and the lipid content of rat molar teeth was studied. The glycine supplementation caused a 65.7% reduction in caries development and a 15.1% reduction in lipid content. In a concurrent balance study, it was noted that the dietary glycine did not have any significant effect on the retention of either calcium or phosphorus by the rat's body. Changes in the fatty acid composition of the tooth and a reduction in growth rate were noted, however.
Biosynthesis of Collagen in Isolated Periodontal Ligament
Authors: Rossman Louis E. , Rosenbloom Joel , Robinson Peter
Published: November 2010

This study showed that the excised periodontal ligament from humans and hamsters actively synthesizes protein, as measured by 14C-proline incorporation, when incubated in vitro for periods of 30 minutes to six hours. However, only a small percentage of the protein synthesized was collagen.
Gelation of Polyacrylic Acid Aqueous Solutions and the Measurement of Viscosity
Authors: Crisp Stephen , Lewis Brian G. , Wilson Alan D.
Published: November 2010

A simple method is described for following changes in viscosity of concentrated aqueous solutions of polycarboxylic acids used in certain dental cements. The difference in behavior over several months between solutions of polyacrylic acid and related polyelectrolytes is discussed.
Production of a Nonwettable Enamel Surface
Authors: Reid J.S. , Macdonald D.G.
Published: November 2010

A water-repellent enamel surface was achieved using a new material that is a combination of fumed silicon dioxide and a silane. The effects of this coating on enamel were studied. In vitro studies suggest that the material produces good water and saliva repellency. However, no reduction in bacterial colonization between treated and control enamel occurred. Results of in vivo investigations of coated and control Styroflex strips showed a reduction in deposits on the former. Retention with or without previous acid etching of the enamel was poor.
Dynamic Mechanical Properties of Maxillofacial Materials
Authors: Koran A. , Craig R.G.
Published: November 2010

Six maxillofacial materials were evaluated by determining their dynamic properties with use of a Goodyear Vibrotester. The dynamic modulus, internal friction, and dynamic resilience were measured for all materials over a temperature range of -15 to 37 C. The dynamic modulus ranged from 11.1 to 124.8 kg/cm2 and the dynamic resilience varied from 1.1 to 63.5%.
Enamel Corrosion Produced by Zinc Phosphate Dental Cement
Authors: Abramovich Abraham , Macchi Ricardo L. , Ribas Lucía M.
Published: November 2010

The surface of tooth enamel that had been left in contact with a phosphoric acid solution or a zinc phosphate cement mix was studied by scanning electron microscopy. Both treatments modified enamel surface topography. The modifications were represented by cavities of varying extension and depth.
Quasimonochromatic Radiation for Dental Radiography
Authors: Huen A. , Sternglass E.J. , Mazzocco D.M. , Fischer W.G.
Published: November 2010

To obtain a high quality dental radiograph, it is advantageous to use 40 kiloelectron volt (kev) monochromatic radiation. The feasibility of obtaining this type of radiation by filtering rays of rare earth elements was studied by a computer program before experimentation. By use of 40 kev monochromatic radiation, skin exposure was reduced by a factor of two to three.
Fracture Properties of Human Enamel and Dentin
Authors: Rasmussen Stephen T. , Patchin Robert E. , Scott David B. , Heuer Arthur H.
Published: November 2010

Work of fracture measurements and scanning electron microscope fractographs show that both enamel and dentin can best be considered as brittle materials with anisotropic fracture properties. Enamel is highly anisotropic, with the weakest path of fracture parallel to the enamel rods. Dentin is less anisotropic, with easiest fracture perpendicular to the dentinal tubules. A model is proposed to explain the fracture behavior of enamel.
Load-Bearing Capacity of Functioning Alumina Dental Endosseous Implants
Authors: Wolfson S.H. , Svare G.W. , Weber D.
Published: November 2010

Ten, solid, 99.7% Al 2O3 implants were sur'gically placed bilaterally in the mandibles of Rhesus monkeys and were then placed in function after two to four weeks. After 95 to 179 days, bone blocks were surgically removed. Load-bearing capacity of the six successful implants was determined as the maximum load that did not produce plastic deformation. The average of this value was 57.5 kg. Histological examination showed excellent bone-implant compatibility.
Relationship Between Fluoride Concentration in Enamel, DMFT Index, and Degree of Fluorosis in a Community Residing in an Area with a High Level of Fluoride
Authors: Bischoff J.I. , Van Der Merwe E.H.M. , Retief D.H. , Barbakow F.H. , Cleaton-Jones P.E.
Published: November 2010

The DMFT index, degree of fluorosis (DEGF), fluoride concentration in enamel (F), and depth of etch (D) were determined in participants living in an area with a high fluoride level. A statistically significant difference was found between men and women for F and D. A significant correlation was established between F and DEGF and between F and age for men, but not for women.
Stress Concentrations at the Apex of Pinned, Implanted Teeth
Authors: Gambrell Samuel C. , Allen Joseph M.
Published: November 2010

Stress concentration factors are studied in the alveolus at the apex of a plane photoelastic model of a representative mandibular left second premolar retained in the alveolus by a metal pin. Stress concentration factors are given for three different pin positions and five different angles of coronal force.
Marginal Leakage of Two Composite Restorative Systems
Authors: Galan João , Mondelli José , Coradazzi João Lucio
Published: November 2010

The ability of sealants to seal margins of composite resins is demonstrated in this in vitro study which uses two composite resins and respective sealants under and over Class V restorations.
Relationship Between Tooth Size and Body Size in American Blacks
Authors: Henderson Avery M. , Corruccini Robert S.
Published: November 2010

The relationship between tooth size and body size of American Blacks, although often statistically significant, is low. This parallels earlier findings for white populations of western european origin. Thus, inferring body size of fossil hominoids from tooth size alone is unwarranted on the basis of these results.
Role of Sucrose in Colonization of Streptococcus mutans in Conventional Sprague-Dawley Rats
Authors: Van Houte J. , Upeslacis V.N. , Jordan H.V. , Skobe Z. , Green D.B.
Published: November 2010

Dietary sucrose, ranging in concentration from 1 to 56%, facilitated greater colonization of Streptococcus mutans on teeth than other carbohydrates. Satisfactory colonization in the absence of sucrose was also achieved, but required higher cell inoculums and appeared to be independent of coprophagy. The intake of a nonsucrose diet did not lead to the elimination of S mutans from the teeth. Other data suggest that S mutans cells have a certain affinity for the teeth in the absence of sucrose that may be of ecological significance, and that bacterial affinity is of importance even for colonization in fissures.
An Apparatus for Measuring the Rheological Properties of Dental Materials
Authors: Combe E.C. , Moser J.B.
Published: November 2010

An indirect extrusion viscometer has been developed and tested on fluids of standard viscosity. Results close to given standards have been obtained and errors in the procedure analyzed. Preliminary tests have shown that the developed apparatus will be suitable for following the viscosity changes during the setting of dental materials.
Cementum Regeneration in Replanted Teeth with Differing Pulp Treatment
Authors: Woehrle Richard R.
Published: November 2010

Mandibular incisors from dogs were replanted and differing pulpal treatments administered after a series of transverse notches were cut in the root surfaces. The pattern of cementum deposition was similar to that reported for nonreplanted teeth. However, the average quantity of new cementum appeared to be influenced by the type of pulpal treatment.
Plasmid DNA Satellite Bands Seen in Lysates of Streptococcus mutans that Form Insoluble Extracellular Polysaccharides
Authors: Higuchi Masako , Araya Shinpei , Higuchi Masataka
Published: November 2010

When two different strains of Streptococcus mutans, PK-1 and JC-2, were used to prepare cell lysates, a satellite band of plasmid deoxyribonucleic acid (DNA) was seen. The mutants of PK-1 and JC-2 were defective in their ability to synthesize insoluble extracellular polysaccharides and had no detectable satellite band of DNA. These mutants were induced by treatment with ethidium bromide, acridine orange, or sodium dodecyl sulfate.
Anticalculus and Antiplaque Activity of 8-Hydroxyquinoline Sulfate
Authors: Depalma P.D. , Loux J.J. , Hutchman J. , Dolan M.M. , Yankell S.L.
Published: November 2010

8-Hydroxyquinoline sulfate inhibited formation of artificial calculus in vitro and rat calculus in vivo. In rats, it prevented calculus formation when applied by swabbing or by intraoral instillation. In dogs, formation of dental plaque was inhibited by 33 to 98% in comparison to placebo. Also in dogs, 25 to 58% of established plaque accumulations were removed by 8-hydroxyquinoline sulfate whereas placebo removed 2 to 22%. No systemic or local toxic effects were observed.
A Model for the Study of Development Processes in Dental Research
Authors: Van't Hof Martin A. , Prahl-Andersen Birte , Kowalski Charles J.
Published: November 2010

In studying developmental processes in dental research, variables other than chronological age must often be taken into account if we are to characterize di$erences in the developmental patterns of the groups under consideration. In particular, in addition to age, appropriate developmental models may have to incorporate cohort, time-of-measurement, and learning effects. One such model is described in this article and applied to caries development and gingival condition in the Nymegen Growth Study.
Studies on Hypoxia: XI. Long-Term Effects on the Epiphyseal Plate—A Histomeric and Radioautographic Study
Authors: Han S.S. , Koo C.S. , Kim M.K.
Published: November 2010

Rats were exposed to hypoxia for one week. The mean thickness of epiphyseal plates from control rats was 430 micrometers (μm) which was reduced to 313 μm in hypoxic rats. Radioautographic incorporation of 3H-phenylalanine by connective tissue cells in hypoxic rats was reduced up to 38% in control rats.
New Method of Bone Preparation for Collagen Fiber Orientation Studies by Means of Scanning Electron Microscopy
Authors: Frasca Peter , Hari Rao C.V. , Harper Richard A. , Katz J. Lawrence
Published: November 2010

A sample preparation technique was developed for observing the orientation of collagen fibers in the lamellas of human osteonic bone by means of scanning electron microscopy. Scanning electron micrographs of these fiber orientations are given in the text.
Eruption Rates of Human Upper Third Molars
Authors: Berkovitz B.K.B. , Bass T.P.
Published: November 2010

Eruption rates of human maxillary third molars varied from 1 mm/2 mo to rates of less than 1 mml6 mo. More rapid rates were associated with spaced dentitions. Gingival recession was invariably associated with crown exposure.
Study of In Vivo Plaque Formation
Authors: Connor James N. , Schoenfeld Charles M. , Taylor Ross L.
Published: November 2010

A technique was developed by which plaque accumulations on intraoral artificial surfaces could be viewed with a scanning electron microscope (SEM). Micrographs of two plaque specimens from a given individual appeared similar; however, plaque specimens from different individuals encompassed a wide range of variation in terms of content and thickness.
Effect of NaF Pretreatments on the Resistance of Powdered Human Dentin to Acid Dissolution
Authors: Thiradilok Sukhum
Published: November 2010

The acid resistance of powdered human dentin increased linearly after pretreatments in 2.5, 25, 250, and 1,000 mM NaF in water. The acid resistance was not directly correlated to the F content of the dentin. The results indicated F uptake by the dentin to be a result of chemical reaction and of adsorption .
Optical Test for the Groove Adaptation of Dental Amalgams Using a He-Ne Laser
Authors: De Rijk Waldemar G.
Published: November 2010

An optical test was developed for amalgam alloys by condensing amalgams against stainless steel blocks with regularly spaced grooves forming diffraction gratings. The quality of the diffraction pattern obtained with a He-Ne laser from these amalgams is a measure of the adaptation to the grooves.
Patterns of Crowding of Permanent Mandibular Incisors Before Eruption
Authors: Kindaichi Kooji
Published: November 2010

Observation of the radiographs taken of 37 mandibles from children ten months to seven years of age showed that the unerupted, permanent mandibular central incisors were rotated in 45 of 74 jaw halves (60.8%). The type of rotation in which the mesial aspect is directed lingually was most commonly seen (44.6%). The next most common observation was of jaw halves without any rotation of the central incisor (39.2%). The type of rotation in which the central incisor's distal aspect is turned lingually was the least common observation (16.2%). The rotation seemed symmetric in 25 jaws (67.6%).
Characteristics of Permanent Teeth in Persons with Trisomy G
Authors: Prahl-Andersen B. , Oerlemans J.
Published: November 2010

Tooth size and morphology in 35 participants with trisomy G and in 33 controls have been studied. Special attention has been paid to the mean cusp pattern of the upper first and second molar. The classification matrix for the linear discriminant function analysis between participants with trisomy G and controls based on five selected variables showed three misclassifications.
Improved Fluoride Incorporation and New in Vitro Fluorine Elemental Determination
Authors: Rajan K.S. , Raisen Elliott , Mandler John W. , Riley Dennis L. , Semmler Richard A.
Published: November 2010

A new, nondestructive technique, charged particle activation, was used to determine the fluorine concentration as a function of depth at 0.1-micrometer (μm) increments in the enamel of human teeth treated in vitro with three different fluorides. Twenty-four-hour treatment with K2ZrF6 showed a 24% fluorine concentration in the first 0.1-μm depth and 14% at 2.5 μm compared, respectively, with 4 and 2.5% concentrations after NaF treatments.
Study of the Arrangement of Crystallites in y-Irradiated Human Enamel by Electron Paramagnetic Resonance
Authors: Cevc P. , Schara M. , Ravnik C. , Skalerič U.
Published: November 2010

The arrangement of tooth enamel microcrystals has been studied on CO33- bound electrons by electron paramagnetic resonance. It was found that noncarious human maxillary central incisors have a greater degree of alignment of tooth enamel microcrystals than the carious ones. The outermost surface layer of enamel showed a greater crystallite degree of alignment than other parts.
Sintering of Dental Porcelain Enamels
Authors: Meyer J.M. , O'Brien W.J. , Yu C.U.
Published: November 2010

This study showed the effects of sintering temperature and atmospheric pressure on the density, tensile strength, and microstructure of porcelain enamels. Although the densities of the opaque porcelains were higher, they were weaker than the gingival porcelains. Gingival porcelains also glazed and sintered at lower temperatures than the opaque porcelains.
Arrest and Control of Carious Lesions: A Study Based on Preliminary Experiments with Resorcinol-Formaldehyde Resin
Authors: Robinson C. , Hallsworth A.S. , Weatherell J.A. , Künzel W.
Published: November 2010

An experimental investigation has been made into the possibilities of retarding the progress of carious attack by infiltrating cariostatic material into enamel lesions. The problems associated with this kind of procedure are discussed against the background of experimental observations made using a formulation based on a resorcinol-formaldehyde resin.
Latex Spheres as Immunologic Markers to Demonstrate the Binding of Human Salivary Immunoglobulins to Streptococcus mutans
Authors: Riviere G.R. , Cotton W.R. , Derkowski J.L.
Published: November 2010

A scanning electron microscopy technique is described that uses latex beads as immunologic markers for detecting the interaction of salivary antibody with Streptococcus mutans. A Labeling Index (beads per bacterial cell) demonstrated that human salivary antibodies bound at a significantly greater degree to S mutans than to non oral bacteria.
Comparison of Dextranases for their Possible Use in Eliminating Dental Plaque
Authors: Goldstein-Lifschitz Batia , Bauer S.
Published: November 2010

Three dextranases produced by Penicillium were compared with respect to their activity and stability at different pH values, to their molecular weight, to their affinity to Sephadex G-25, and to their action on dextrans that contain varying proportions of different bonds. The enzyme produced by P funiculosum strain NRRL 1768 is considered a suitable enzyme for use in an enzymatic dental plaque elimination system.
Influence of Amalgam, Alloy, and Hg on the In Vitro Growth of Streptococcus mutans: III. Effect of Specimen Age and Composition
Authors: Nunez Loys J. , Schmalz Gottfried , Hembree John H.
Published: November 2010

In vitro growth inhibition of Streptococcus mutans is lost with sample age at different rates for amalgams Prepared from a spherical, fine cut, and dispersion alloy. Varying the Hg composition from 48 to 52% has little effect on growth inhibition.
Optical Method for Articulator Comparison and Study of Occlusal Determinants
Authors: Finger Israel M. , Foreman Dennis , Tanaka Hisatoshi
Published: November 2010

Optical and other instrumentation have been used to measure articulator movements; subsequently, specific angles were calculated, normalized, and compared for the Stuart and the Hanau XP-51 articulators in an attempt to assess the practical applicability of the latter.
Erythrocyte Velocity in Vascular Networks of Young Noninflamed Dog Gingiva
Authors: Hock J. , Nuki K.
Published: November 2010

Measurements of erythrocyte velocity in vascular networks of noninflamed gingiva of deciduous canines of four young dogs were obtained using vital microscopy and highspeed cinePhotomicrograPhy. Mean erythrocyte velocity in small gingival vessels was 1.59 ± 0.29 mm/sec. Differences in erythrocyte velocity of vessels comprising a gingival microcirculation and of vessels within different gingival samples were not significant.
Cariostatic Activity of Calcium Glycerophosphate in Hamsters: Topical Vs Dietary Administration
Authors: Pianotti R.S. , Ambrozaitis J.D. , Mc Namara T.F.
Published: November 2010

Hamsters were used to determine the effect of calcium glycerophosphate on dental caries. Within the 60-day experimental period, calcium glyceroPhosPhate significantly reduced caries when fed in the diet at levels of 1% and higher, and when applied topically at levels of 2% and higher.
Estimating Examiner Consistency with DMFS Measures
Authors: Slakter Malcolm J. , Juliano Daniel B. , Fischman Stuart L.
Published: November 2010

Within- and between-examiner reliability estimates were considered for standardization data. However, within-examiner stability was demonstrated to be the important measure of examiner consistency in the clinical trial because it directly affects the precision of the study. Finally, an argument is also made against the use of reversal rates in the assessment of examiner consistency.
Measurement in Vitro of Enamel Abrasion by Dentifrice
Authors: Davis W.B. , Winter P.J.
Published: November 2010

An in vitro method of measuring the abrasivities of dentifrices and abrasive powders on human dental enamel has been developed. The method, based on a proven dentin abrasivity method, records, in absolute terms, the abrasive effects of brushing flat, nonirradiated, enamel specimens beneath an aqueous slurry of the test material with the use of a surface profile meter.
Fluoride Deposition in Human Enamel In Vivo from Professionally Applied Fluoride Prophylaxis Paste
Authors: Mellberg J.R. , Nicholson C.R. , Ripa L.W. , Barenie J.
Published: November 2010

Deciduous teeth were collected from children who received professional prophylaxis with an acidulated phosphate-fluoride (APF) or placebo paste and were analyzed to determine fluoride uptake. Enamel fluoride level was increased by the APF paste approximately 300 ppm at a depth of 2.5 micrometers during the first month after the prophylaxis was administered, after which it returned to pretreatment levels.
Ceramic Hydroxylapatite as a Plaque Growth and Drug Screening Substrate
Authors: Jarcho M. , O'Connor J.R. , Paris D.A.
Published: November 2010

The preparation and use of a ceramic hydroxylapatite plaque growth and drug screening substrate is described. This material has been shown to closely mimic dental enamel in vitro in regard to the rate of plaque accumulation and the effectiveness of antiplaque drugs.
Isoproterenol and G2 Acinar Cells in the Developing Rat Parotid Gland
Authors: Klein Robert M. , Harrington Daniel B.
Published: November 2010

In the present study, premitotic period (G2)-delayed or blocked acinar cells were identified in the parotid gland of the neonatal rat. The noncycling G2 cells retain the potential to divide and respond to administration of the sympathomimetic amine, isoproterenol (IPR). The effects of IPR on suckling and weaned rats were compared. Both groups showed the presence of G2-acinar cells with a possible age-related change occurring after weaning.
Sources of Variability in Rat Caries Studies: Weaning Age and Diet Fed During Tooth Eruption
Authors: Navia J.M. , Lopez H.
Published: November 2010

A factorial design (2 × 2) was used to study the caries effect of two diets (starch based versus stock) fed to rat dams and their litters, and also of variations in the weaning age (19 versus 25 days). Higher and reproducible caries scores were obtained in rats which were fed a purified starch-based diet, weaned at 19 days of age, and subsequently given a cariogenic challenge.
The Instantaneous Transverse Changes in the Maxilla Due to Different Points of Force Application
Authors: Marcotte Michael Roger
Published: November 2010

The effects of different sites of an expansile force on the maxillae of three monkeys were studied. A lateral force of five pounds was delivered directly to four locations on each maxilla. Aluminum rods, rigidly attached to the teeth of each buccal segment, were photographed before and after each force application. The data indicated that the pattern of lateral maxillary displacement is related to the position of the lateral force in relation to the center of resistance of each maxilla.
Unusual Dissolution Behavior of Tooth Enamel and Synthetic HAP Crystals Under High Partial Saturation Conditions
Authors: Fawzi M.B. , Higuchi W.I. , Hefferren J.J.
Published: November 2010

The dissolution behavior of enamel and synthetic hydroxyapatite in acidic media possessing a high degree of partial saturation was found to be neither simple surface dissolution nor linear with time. Instead, a repetitive, stepwise dissolution pattern was observed. To explain this phenomenon, a model based upon a hypothesis that the crystals dissolve in a synchronized fashion was proposed.
Microbial Characterization of an Experimental Cariogenic Plaque in Man
Authors: Ostrom Carl A. , Koulourides Theodore , Hickman Frances , McGhee Jerry R.
Published: November 2010

Experimentally induced plaque seemed to originate by direct contact inoculation from the vestibular mucosa and saliva. During the next seven days, this plaque developed its own characteristics. Populations of Streptococcus mutans, usually less than 2% of total streptococci population in plaques that were less than three days old, increased between days 3 and 7. Proportions of S sanguis, high in early samples, decreased after day 3. Populations of S salivarius, which usually outnumbered other streptococci, fluctuated widely through day 3, and then increased in proportion in subjects who were more productive of experimental caries, but decreased in subjects who were less productive. Proportions of plaque flora comprising lactobacilli paralleled those of S salivarius.
Effects of Polyphosphates on the Solubility and Mineralization of HA: Relevance to a Rationale for Anticaries Activity
Authors: McGaughey Charles , Stowell Ellery C.
Published: November 2010

Preexposure of hydroxyapatite (HA) to polyphosphate reduced the near-equilibrium acid solubility of HA, the mineralization of HA, and the exchange of PO4 between medium and HA. Appreciably longer exposure times were required for maximal effects of trimetaphosphate (TMP) than of pyrophosphate (PP), tripolyphosphate (TPP), and hexametaphosphate (HMP). Calcifying solution solubilized small amounts of the HA-bound polyphosphates. This occurred to the smallest extent in the case of TMP, a fact which could have relevance for the superior anticaries effect of TMP.
Duration of the Electromyographic Silent Period Following the Jaw-Jerk Reflex in Human Subjects
Authors: McNamara David C. , Crane Patrick F. , Mccall Willard D. , Ash M.
Published: November 2010

During voluntary jaw clenching, a sharp tap to the menton of the mandible resulted in a transitory silent period (pause) in the electromyographic activity of the masseter and anterior temporalis muscles. Factors that could influence the duration of the silent period were studied, including direction and magnitude of the stimulus applied by the operator, the amount of muscular effort exerted by the subjects, and varying occlusal vertical dimensions. Decreased isometric muscle force resulted in statistically significant increases in silent period durations.
Effects of GK-101 (NMG) and Sodium Hypochlorite on Salivary Amylase Activity
Authors: Habib Charles M. , Kronman Joseph H. , Goldman Melvin , Cushner Stuart
Published: November 2010

A study was designed to assess the effects of the sodium salt of N-monochloroglycine (NMG) and sodium hypochlorite on the activity of salivary amylase. Concentrations of each agent were varied to determine the concentration at which the threshold and total inhibition of enzyme would be obtained. The data indicated that NMG at concentrations of 0.10% (w/v) does not affect amylase activity, whereas sodium hypochlorite at concentrations of 0.05% (w/v) totally inhibits salivary amylase activity.
Antiplaque Potential of Topical Stannous Fluoride
Authors: Hoffman S. , Tow H.D. , Cole John S.
Published: November 2010

Sterile enamel samples treated by topical application of 10% stannous fluoride were incubated with S mutans and S sanguis respectively and with a mixed culture to which L casei had been added. The results were compared with sterile nonfluoridated enamel samples subjected to the same procedures. The parameters compared were postincubation pH values, bacterial concentrations on the surfaces, and enamel surface alterations. Stannous fluoride treated samples consistently yielded higher pH readings than nonfluoridated samples; the concentration of microorganisms adhering to the surfaces was conspicuously reduced on the pretreated enamel when compared by scanning electron microscopy to untreated samples, as were enamel surface alterations. These findings lend support to other recent investigations which have shown that fluorides act in several ways to inhibit cariogenesis in addition to reducing hydroxyapatite solubility.
Apparent Cytotoxicity of Base Metal Casting Alloys
Authors: Woody Ronald D. , Huget Eugene F. , Horton John E.
Published: November 2010

The cytotoxic potential of four alloy materials was tested; three were Ni-Cr based alloys and one was a Fe-Cr based alloy. Adverse cellular changes were not found in tissue culture studies of castings of the alloys. Cultures containing Ni-Cr powders did show prominent zones of lysis and cell alteration. The cytologic potential of products obtained from surfaces of casting alloys may offer means for estimating long-term clinical toxicity.
Free Surface Energy Change for Water Adsorbed on Hydroxyapatite
Authors: Rootare Hillar M. , Craig Robert G.
Published: November 2010

The free energies of immersion for three hydroxyapatite samples of different origin and method of preparation were determined from water adsorption isotherms at 20 and 25 C. The free energies varied with the temperature of the isotherm, changing linearly with the outgassing temperature in the range of 20 and 300 C. The samples outgassed at 300 C yielded free energy of immersion values of 365, 432, and 476 ergs/ cm2 for the VIC-, NBS-, and TVA-HAP, respectively. Work of adhesion and work of spreading were calculated for water on these samples.
Color of Denture Resins
Authors: Powers John M. , Koran Andrew
Published: November 2010

The color of 24 commercially available denture resins was determined visually with Munsell color tabs and by reflection spectrophotometry. Correlation between Munsell and spectrophotometric data was found. The resins characterized for Black patients had a higher degree of specular reflectance and were more opaque than resins for Caucasians.
An Evaluation of Porous Alumina Ceramic Dental Implants
Authors: Klawitter Jerome J. , Weinstein Allan M. , Cooke Francis W. , Peterson Larry J. , Pennel Billy M. , Mckinney Ralph V.
Published: November 2010

The fabrication, characterization, and clinical results of porous rooted alumina dental implants in animals are presented. Failures of all implants occurred in less than six months and were attributed to the presence of microporosity on the crown and cervical portion of the implant which prevented the establishment of an effective bialogical seal between the oral cavity and the alveolus.
Blood and Urinary 18F Pharmaco kinetics Following Parenteral Administration in the Rat
Authors: Whitford Gary M. , Patten Jimmy R. , Reynolds Keith E. , Pashley David H.
Published: November 2010

Blood and urinary excretion time courses of 18F administered parenterally to rats were monitored for two hours. The intraperitoneal, subcutaneous, and intravenous routes gave kinetically indistinguishable results after ten minutes following the dose. The blood time course during the first hour following intramuscular dosing showed a relative constancy and suggested a delayed absorption time.
Animal Studies Concerning the Cariogenicity of Dry Breakfast Cereals
Authors: McDonald James L. , Stookey George K.
Published: November 2010

Four studies were performed in rats and hamsters concerning the cariogenicity of cereals and the role of sucrose in that process. The findings indicate that sucrose content per se does not necessarily reflect the cariogenic potential. Presweetened cereals were more conducive to the formation of smooth surface caries in the hamster than were non-presweetened cereals while no major differences between the cereals were observed in occlusal caries in rats.
Root Surface Caries in the Molar Teeth of Rice Rats. 1. A Method for Quantitative Scoring
Authors: Doff Richard S. , Rosen Samuel , App George
Published: November 2010

A new system was devised for scoring root surface caries. The roots were divided circumferentially and apically into areas. Each exposed area and any carious involvement was given a score of 1. Root surface caries was expressed, as total areas affected and as a percentage of the exposed root surface.
Study of the Noncollagenous Components of the Periodontium
Authors: Mickalites Carey , Orlowski Walter A.
Published: November 2010

Periodontal ligament and gingivae of bovine and porcine periodontium were analyzed for relative amounts of carbohydrates, collagen, and acid mucopolysaccharides. The sugar content was 3.6% and 3.4% of dry weight in bovine and porcine periodontal ligament, respectively. The values were lower in the gingivae being 2.34% and 2.30%, respectively. Approximately 50% of hexosamine in gingivae was present in acid mucopolysacchrides as compared to 36% in periodontal ligament. Relative to collagen there was a considerable amount of noncollagenous glycoproteins present in the periodontium as judged by carbohydrate content of the tissue.
Evaluation of Oral Submucosal Blood Flow at Dental Injection Sites by Radioactive Xenon Clearance in Beagle Dogs
Authors: Trapp Larry D. , Goodson J. Max , Price David C.
Published: November 2010

Oral submucosal blood flow was measured at dental injection sites in anesthetized dogs and compared with subcutaneous blood flow. Blood flow was calculated from the measured half-time for clearance of radioactive xenon dissolved in saline. By this method, oral submucosal blood flow was much greater than subcutaneous blood flow and was comparable in magnitude to values reported for cerebral blood flow. Injection of a solution containing 1:100,000 epinephrine at the mandibular canal produce a delayed clearance of isotope which was three times as long as the clearance time for solutions without epinephrine.
Basic Biological Sciences
Authors: Yen Peter K-J. , Shaw James H.
Published: November 2010

Remodeling of the osteons or Haversian canal system in compact bone was studied in young monkeys that received serial injections of lead acetate as an intravital strain. The successive stages of the formation of an osteon have been demonstrated. The rate of the filling of the lamellar bone decelerated as the lumen of the Haversian canal decreased. The total formation time of individual osteons was estimated.
Proteolipid and Bone Matrix Calcification In Vitro
Authors: Ennever John , Boyan-Salyers Barbara , Riggan Linda J.
Published: November 2010

Proteolipid was demonstrated to contain the nucleator of bone matrix calcification, in vitro. Crude Phospholipid extracted from bone matrix was fractionated by gel filtration. A single, protein-containing fraction induced apatite crystallization in a metastable calcium phosphate solution. The fraction was identified as proteolipid. The result supports the validity of a microbiologic analogue for vertebrate calcification.
Measurement and Synthesis of Insoluble and Soluble Dextran by Streptococcus mutans
Authors: Montville Thomas J. , Cooney Charles L. , Sinskey Anthony J.
Published: November 2010

Total and insoluble dextransucrase activities of 10 strains of oral streptococci were measured by a modified filter disk assay. Strains that were nonadherent to hard surfaces had only low levels of insoluble dextransucrase activity.

A physical rather than metabolic mechanism is suggested to explain the decreased insoluble and increased soluble activities observed when dextran T-10 is added to the media.
Adherence Controlling Elements in Ceramic-Metal Systems. II. Nonprecious Alloys
Authors: Anusavice Kenneth J. , Ringle Robert D. , Fairhurst Carl W.
Published: November 2010

Nickel-chromium alloy-ceramic couples used in this study exhibited Cr, Ni-Cr, and Ti-Cr interactions with bonding agent-ceramic complexes. Bonding agents may broaden or suppress the width of interaction zones. Metal oxides such as NiO, Cr2O 3, or more complex forms such as TiO · Cr2O3 and NiCr2O4 may play a prominent role in controlling ceramic-metal adherence.
Effects of Daily Rinses Using Sodium Fluoride and Organic Fluorides on Rat Caries
Authors: Shern Roald J. , Amsbaugh Suzanne M. , Ransom Reynolds G.
Published: November 2010

The organic fluorides, alexidine dihydrofluoride and amine fluoride, provided greater protection against caries than sodium fluoride when used as a daily mouthrinse in rats. Alexidine dihydrochloride also provided significant caries restriction.
Crown Component Variation in the Hominoid Lower Second Premolar
Authors: Corruccini Robert S.
Published: November 2010

An exploratory analysis of crown component measurements illustrates a great increase in retrieval of morphological information over the more conventional measurements of maximum dental length and breadth.
Levan Production by a Strain of Rothia: Activation of Complement Resulting in Cytotoxicity for Human Gingival Cells
Authors: Lesher R.J. , Gerencser V.F.
Published: November 2010

An extracellular polysaccharide identified as a levan has been isolated from Rothia dentocariosa, strain 477 serotype 2. The levan produced by strain 477 has been found to activate the complement cascade in the absence of specific antibodies. This activation was found to be cytotoxic for human gingival cells in tissue culture.
In Vitro Enamel Demineralization by Streptococcus mutans in the Presence of Salivary Pellicles
Authors: Zahradnik R.T. , Propas D. , Moreno E.C.
Published: November 2010

Salivary pellicles developed on extracted teeth favorably affected the degree and nature of enamel demineralization when the teeth were incubated in vitro with either of two pure strains of cariogenic Streptococcus mutans. The mechanism responsible for this protection may relate to the permselective properties of these salivary pellicles.
Dentin Permeation: Comparison of Diffusion with Filtration
Authors: Merchant V.A. , Livingston M.J. , Pashley D.H.
Published: November 2010

A comparison was made between the rate of iodide permeation of dentin by diffusion and by filtration. Before acid etching, filtration only doubled the rate of iodide permeation relative to that obtained by diffusion. After acid etching, filtration produced a 32-fold increase in permeation. Acid etching, by removing occluding debris, facilitates filtration more than diffusion.
The Effects of Fluoride on the Percentage Bacterial Composition of Dental Plaque, on Caries Incidence, and on the In Vitro Growth of Streptococcus mutans, Actinomyces viscosus, and Actinobacillus sp
Authors: Beichton David , Mcdougall W.A.
Published: November 2010

Administration of 250 μ g/ml NaF in drinking water to rats reduced both caries incidence (P < 0.001) and the percentage of S mutans (0.01 > P > 0.001) although the percentage of Actinobacillus sp. was increased (P < 0.001). An Actinobacillus sp. and S mutans FA1 both proliferated in NaF broth only if the NaF > 10 μ g/ml. which was associated with the inhibition of acid production.
Clinical Study of Dental Cements. VI. A Study of Zinc Phosphate, EBA-Reinforced Zinc Oxide Eugenol and Polyacrylic Acid Cements as Luting Agents in Fixed Prostheses
Authors: Silvey Ralph G. , Myers George E.
Published: November 2010

Three cements were used to cement single restorations and bridges. Patients were recalled and evaluated for satisfactory retention of the restorations. Results obtained for a zinc phosphate cement, a reinforced zinc oxide eugenol cement and a polyacrylic acid cement are presented.
Phagocytosis of Collagen by Human Gingival Fibroblasts in Vitro
Authors: Yajima Toshihiko , Rose George G.
Published: November 2010

Human gingival fibroblasts cultivated on collagen-coated cover slips had collagen fibrils in deep folds of the cell membranes after one hour and fully interiorized fibrils by 24 hours. In 5-day sections, fibrils were within dense bodies, some containing multiple dense granules (40 to 50 nm) aligned along the surface of the interiorized collagen fibrils.
A Method for the In Vitro Toxicity Testing of Dental Restorative Materials
Authors: Tyas Martin J.
Published: November 2010

An in vitro method of toxicity testing of dental restorative materials is described in which their clinical usage is closely simulated. The test material was separated from the cells by either a synthetic filter or dentine slice. Toxic effects were quantitated by determining changes in enzyme activity by scanning and integrating microdensitometry.
Graphic Digitizer Analysis of the Myelinated Axon Spectrum in the Inferior Alveolar Nerve of the Cat
Authors: Biedenbach M.A. , Brown A.C.
Published: November 2010

The diameter spectrum and other parameters indicating size and shape of myelinated axons were established in a cross-section of the inferior alveolar nerve obtained at the mandibular foramen. The spectrum is bimodal with approximately equal numbers of axons in the Aa and AS-range, in contrast to unimodal spectra of certain branches contributing to the inferior alveolar nerve.
The Effect of Topical Application with an Organic and Inorganic Fluoride Compound on the Inhibition of Dental Plaque in Humans
Authors: Weiss E. , Gedalia I. , Zilberman Y.
Published: November 2010

Accumulation of dental plaque for 3 and 7 days respectively was determined by calculating the difference between the postcollection and precollection weights of enamel slabs attached to orthodontic bands cemented to the upper first molars of 3 subjects. Pretreatment of the enamel slabs with amine-fluoride or -chloride respectively-at an equivalent amine concentration-prevented plaque deposition on the slabs, whereas pretreatment with sodium monofluorophosphate was less effective. The fluoride concentrations of all fluoride-pretreated enamel slabs were similar. No convincing demonstration of significant differences between the treatments could be predicted in view of the discrepancy in results at the 3- and 7-day test periods.
Effects of Alexidine·2HCl Mouthwash on Plaque and Gingivitis after six Months
Authors: Spolsky Vladimir W. , Forsythe Alan B.
Published: November 2010

Two-hundred and fourteen subjects ranging in age from 22 to 63 years used either a mouthwash that contained 0.035% w/v alexidine· 2HCl (2-ethylhexyl bisbiguanidine dihydrochloride) or a placebo twice daily on a double-blind basis for six months in conjunction with routine oral hygiene procedures. The results indicated that alexidine·2HCl was safe and was statistically more effective in producing a clinically significant reduction in gingivitis than was the placebo.
Chlorhexidine and Fluoride in Prevention of Plaque and Caries in Hamsters
Authors: Brayer L. , Gedalia I. , Gover A.
Published: November 2010

The effect of combined administration of chlorhexidine and fluoride in the drinking water of hamsters on plaque and caries prevention was studied. Plaque indices of the hamsters receiving chlorhexidine either alone or simultaneously with fluoride were significantly lower than those of the control and fluoride only treated hamsters. The type of plaque indices used in this investigation was area scores. The necessity of quantitatively assessing plaque by several parameters was emphasized. The degrees of caries of the experimental groups were significantly lower than of the control group during the cariogenic diet regime. The anti-cariogenic effect of chlorhexidine and fluoride at low concentrations each provided simultaneously with a cariogenic diet, was confirmed. The differences in caries rate between the experimental groups were not significant. No additive effect on the cariostatic action of chlorhexidine and fluoride was observed when both reagents were applied simultaneously due probably to the low F concentration in the drinking water. The results did not show a direct quantitative relationship between plaque and caries.
The Seeded Growth of Calcium Phosphates on Dentin and Predentin
Authors: Tomson M.B. , Tomazic B. , Nancollas G.H. , Miller W. , Everett M.
Published: November 2010

The in vitro mineralization of predentin (PD) and of the organic component of dentin (OD) has been studied in a supersaturated solution of calcium phosphate at 37 C and pH = 7.4 at total calcium and phosphate concentrations close to those in vivo. The mineralization of OD can be divided into at least three periods based upon the morphology and the specific surface area of the mineral phase formed. Dissolution of the newly precipitated mineral on OD revealed a stoichiometry close to that for octacalcium phosphate. In contrast, PD was ineffective as a crystal nucleator. The mineralization of the inorganic component of dentin (ID) and whole dentin (D) has also been examined.
Growth of the Fetal Rat Craniofacial Complex Secondary to the Postfusion Rupture of the Palate
Authors: Goss Alastair N.
Published: November 2010

Isolated cleft palate was created by in utero surgical rubture of the prev ously intact rat palate. Cephalometric analysis was performed on mandibular and maxillary growth and on nasal septal height. The findings showed that the surgical procedure has no effect, beside cleft palate production, on continuing fetal craniofacial growth.