bluuebunny/crossref_metadata_2025 huggingface dataset:
Vapor Phase Adsorption of Water on Hydroxyapatite
Authors: Rootare Hillar M. , Craig Robert G.
Published: November 2010

Water vapor adsorption isotherms were determined gravimetrically on three hydroxyapatite samples differing in preparation and with surface areas of 70.4, 22.5, and 3.0 M 2/gm, respectively. Heats of adsorption for the first layer of water were found to be 13.3, 13.2, and 13.9 kcallmole on these hydroxyapatites. From repeated thermal desorption and adsorption cycles of water, stepwise adsorption was observed which diminished with each outgassing cycle until it disappeared after the fourth cycle. Cross-sectional area of adsorbed water molecule on hydroxyapatite surface was estimated at 11.5 Å2. Standard free energies, isosteric heats, changes in enthalpy, and entropy of adsorption of water on HAP samples outgassed at 300 C were determined.
The Principal Stress Distribution in a Root with a Loaded Post in Model Experiments
Authors: Dérand Tore
Published: November 2010

The princapal stress distribution in a root with a loaded post was analyzed in model experiments, in which emphasis was directed to the cervical boundary of the root where the stresses are greatest. Maximum stresses were found in the inner proximal sides, and were stronger when the prepared root canal walls were parallel. When contact between post and root was reduced, stresses decreased. These findings point to the importance of sparing tooth substance in the proximal parts of the canal in order to reduce the risk of breaking the cement layer and loosening the post.
Amalgam Containing Nickel or Tungsten Dispersions. I
Authors: Reisbick M.H. , Bunshah R.F. , Agarwal N.
Published: November 2010

Wetting tests were conducted to determine compatability between select dispersion powders and Ag3 Sn. Subsequently, a method was perfected for incorporating nickel or tungsten powder into the Ag3Sn ingot. Initial studies reveal good distributions of the dispersed phase in the ingots and the comminuted alloys, after amalgamation, appear to retain their normal working characteristics.
Amalgam Containing Nickel or Tungsten Dispersions. II
Authors: Reisbick M.H. , Bunshah R.F. , Agarwal N.
Published: November 2010

The technique of injecting dispersed phase particles into an Ag-Sn melt followed by rapid quenching was utilized. Results of this investigation show that a marked improvement of the brittle amalgam alloy occurs.
A Flexural Method for Evaluation of Metal-Ceramic Bond Strengths
Authors: Caputo A.A. , Dunn B. , Reisbick M.H.
Published: November 2010

A test technique is presented for evaluating metal-ceramic bond strengths. The test piece consists of a four-point loaded metal beam with porcelain bonded to the central tension side of the beam. The test produced failures at predictable locations and was able to differentiate between metal surface treatments.
Dimensional Changes of Periodontal Dressings
Authors: Gjerdet N.R. , Haugen E.
Published: November 2010

The linear dimensional changes of three commercial periodontal dressings were measured during 24 hours. The dressings revealed different degrees of dimensional changes, which may indicate that they exhibit variations in adaptation to wound surfaces.
Increased Fibrinolytic Activity in the Inflamed Gingiva of Beagle Dogs
Authors: Lucas Oscar N.
Published: November 2010

The fibrinolytic activity originated by activation of plasminogen was found to be greater in the inflamed gingiva than in the normal gingiva. The activator of plasminogen present in the normal and inflamed gingiva of the beagle dog was demonstrated histochemically. Plasminogen activator was found adjacent to the crevicular epithelium and blood vessels.
Electron Microscopic Evaluation of Altered Collagen Structure Induced by N-Monochloroglycine (GK-101)
Authors: Kronman J.H. , Goldman M. , Habib C.M. , Mengel L.
Published: November 2010

The effects of N-monochloroglycine (NMG) solutions on the structure of collagen were studied by transmission electron microscopy. In addition to finding that collagen structure was altered by NMG solutions, the results offer evidence that buffer and water also exert some effect on collagen fiber structure.
Studies on Calcium-Stimulated Adenosine Triphosphatase in the Albino Rabbit Dental Pulp. Its Subcellular Distribution and Properties
Authors: Abiko Yoshimitsu
Published: November 2010

The subcellular distribution of calcium-stimulated adenosine triphosphatase in the albino rabbit dental pulp was studied. The purity of the microsomal fraction was examined by measuring the marker enzymes and by electron microscopic observation. Some properties of calcium-stimulated adenosine triphosphatase were investigated.
Osteodentin Formation in Continuously Erupting Teeth of Guinea Pigs
Authors: Holmstedt Jan O.V. , Mcclugage Sam G. , Clark John S. , Guevara Michael J.
Published: November 2010

Osteodentin formation in guinea pig teeth was studied using in vivo microscopic and histologic techniques. The coronal half of both incisors and molars contained varying amounts of osteodentin. Within the osteodentin, narrow canals that contained pulp tissue were observed. Serial histologic sections demonstrated that these canals opened to the occlusal surface thereby exposing the pulp to the oral cavity.
The Effect of a Magnesium Deficient Diet and Cortisone on the Growth of the Rat Incisor
Authors: Kiely Michael L. , Domm L.V.
Published: November 2010

Incisors of Mg-deficient rats showed a marked inhibition of eruption and a decrease in mitoses of apical tissues. Cortisone administration resulted in some increase in eruption rate and cell division though these remained below the values of Mg-supplemented controls. An improvement in gross condition and a less severe histopathology of incisor tissues were also observed in cortisone-treated rats.
Immunization with Dextransucrases, Levansucrases, and Glycosidic Hydrolases from Oral Streptococci. II. Immunization with Glucosyltransferases, Fructosyltransferases, and Glycosidic Hydrolases from Oral Streptococci in Monkeys
Authors: Bahn Arthur N. , Shklair Irving L. , Hayashi James A.
Published: November 2010

The feasibility of immunizing monkeys with enzymes from oral streptococci in an attempt to reduce dental caries was investigated. Forty rhesus monkeys, Macaca mulatta, were used. Cariogenic streptococci, S mutans, were implanted into all the monkeys' mouths. There was no pathological effect resulting from immunization. Of the 40 animals, 30 retained the implanted flora throughout the experiment; the remaining 10 were reimplanted until the streptococci remained. In six months, gross carious lesions were evident with plaque. Inhibitors present in the monkey sera after immunization inhibited glucosyltransferase, fructosyltransferase, and neuraminidase activzties. It was presumed the inhibitors were antibodies. There was a reduction of 68.6% in the total carious lesions in the animals immunized intraorally with glucosyltransferase, 62.4% reduction in those injected with fructosyltransferase, and 57.4% reduction in total lesions in those immunized with glycosidic hydro lases after 19 months, as compared to the control group. There were no gross lesions apparent in the group immunized with glycosidic hydrolases. It appears that immunization with enzymes significantly reduces caries and is feasible in a primate model.
Laser Evaluation of Handpiece Contamination
Authors: Pelzner Roger B. , Kempler Daniel , Stark Marvin M. , Barkin Paul R. , Graham David A.
Published: November 2010

Six different models of ultra-high speed handpieces were evaluated in regard to debris accumulation following cutting through tooth structure. A weight-load machine and a laser particle detector were utilized to evaluate the amount of the debris retained. Amounts of debris accumulated after dry and wet cutting were also evaluated. The effect of simple wiping of the handpieces with alcohol gauze was assessed. The results obtained show that the longer the cutting time, the larger the amounts of debris retained on the handpieces. Dry cutting resulted in smaller amounts of debris entrapped than following wet cutting. The cleaning by wiping with alcohol gauze reduced the amounts of the debris, but is insufficient and cannot be utilized as a single procedure for decontaminating handpieces. The external head design is a cardinal factor in retention of debris: larger but smoother surfaces will retain less debris than smaller but more complicated surfaces. External tubings are debris retention foci.
Identification of N-Methylated Basic Amino Acids from Human Adult Teeth
Authors: Kalasz Huba , Kovacs Georgina H. , Nagy Janos , Tyihak Ernö , Barnes William T.
Published: November 2010

NE-monomethyl-lysine, NG-NG-dimethyl-arginine, and NG-NG' -dimethyl-arginine from tooth protein fractions were identified utilizing thin-layer chromatography, amino acid analysis, and gas chromatography. It is suggested that a relationship exists between the presence of these N-methylated basic amino acids and the resting stage of tooth tissue.
8-Hydroxyquinolines with the Potential for Long-Term Anticaries Activity: Design, Synthesis, and In Vitro Evaluation
Authors: Mirth Dale B. , Chite Anthony F. , Schuster George S.
Published: November 2010

8-Hydroxyquinolyl benzoate and 8-hydroxyquinolyl para-(fluorosulfonyl)benzoate have been synthesized and evaluated in vitro as antimicrobial and antiplaque agents. Both compounds inhibited the growth of cultures of the following genera: Streptococcus, Staphylococcus, Actinomyces, Lactobacillus, Veillonella, and Candida. Minimum inhibitory concentrations ranged from 0.98 to 62 μg/ml. Extracted human teeth pretreated with 1% solutions of either compound and rinsed with distilled water exhibited reduced in vitro plaque formation for 48 hours. These results indicate that the in vitro antiplaque activity of 8-hydroxyquinolines can be enhanced by attaching the appropriate side chain in the 8-position.
Effect of Perceived Control on Stress Reduction in Adult Dental Patients
Authors: Corah Norman L. , Bissell G. Donald , Illig Stephen J.
Published: November 2010

A signaling device was given to adult patients to reduce stress in the dental chair. Galvanic skin response during the dental procedures indicated that patients with the signaling device showed more arousal during high stress conditions when compared with a control group. A personality variable was also investigated.
Regulation of the Secretory Process of Granular Components from the Convoluted Tubular Cells of the Mouse Submandibular Gland
Authors: Hosoi Kazuo , Aoyama Kazushi , Ueha Takao
Published: November 2010

Autonomic regulation of the secretion of granule components in the convoluted tubular cells of male mouse submandibular glands was investigated with the use of an agar gel diffusion test using an antisera for male specific components. Whereas the injection of neither a parasympathomimetic agent (pilocarpine) nor a β-adrenergic agent (isoproterenol) decreased the amount of the components in the glands, the injection of α-adrenergic agents (norepinephrine or phenylephrine) significantly decreased the amount of male specific components. Phenoxybenzamine, an a-blocker, completely inhibited these actions of norepinephrine and phenylephrine. These facts suggest that the a-adrenergic receptor participates in the secretion of male specific components present in the granules in the convoluted tubular cells of mouse submandibular glands.
Studies on Hemolytic Activity of Bisphenol A Diglycidyl Methacrylate (BIS-GMA)
Authors: Fujisawa S. , Imai Y. , Fujisawa  , Kojima K. , Fujisawa  , Masuhara E.
Published: November 2010

To clarify the high hemolytic activity of BIS-GMA, the molar concentration producing 50% hemolysis (H 50) and the partition coefficient in-octanol-water were determined using BIS-GMA and various types of methacrylates. It is suggested that the strong hemolytic potency of BIS-GMA is due to the high hydrophobic nature of the compound.
Effect of Toothbrushing with Different Concentrations of Chlorhexidine on the Development of Dental Plaque and Gingivitis
Authors: Bay Lena M.
Published: November 2010

This study showed that 0.15, 0.10, and 0.05% chlorhexidine gluconate solutions used on the toothbrush subsequent to scaling were for at least 45 days able to maintain plaque and gingivitis scores lower than those obtained 14 days after scaling and oral hygiene instruction. Discolorations of teeth and fillings were the only side effects observed.
Early Detection of Occlusal Caries by Measuring the Electrical Resistance of the Tooth
Authors: White George E. , Tsamtsouris Anthi , Williams David L.
Published: November 2010

The tooth resistance measuring instrument was compared to the traditional method of the explorer examination for the detection of occlusal carious lesions. The findings of the instrument were more sensitive as compared to the traditional method when verified by a histological examination.
Infrared Spectroscopic Studies on the Development of Crystallinity in Dental Zinc Phosphate Cements
Authors: Crisp Stephen , O'Neill Ian K. , Prosser Havard J. , Stuart Brian , Wilson Alan D.
Published: November 2010

An infrared spectroscopic study has been made of the development of crystallinity (hopeite) in dental zinc phosphate cements. Crystallization in the bulk of a cement is prevented only by the incorporation, in the liquid, of aluminum which forms complexes with phosphoric acid. The development of surface crystallinity is related to the chemical composition of the cement and the speed of the reaction. No acid phosphates are to be found in the matrix which consists solely of neutral orthophosphates.
Pressure Distribution in Centrifugal Dental Casting
Authors: Nielsen John P.
Published: November 2010

Equations are developed for liquid metal pressure in centrifugal dental casting, given the instantaneous rotational velocity, density, and certain dimensions of the casting machine and casting pattern. A "reference parabola" is introduced making the fluid pressure concept more understandable. A specially designed specimen demonstrates experimentally the reference parabola at freezing.
Estimation of the Phase Distribution in Dental Amalgam with the Electron Microprobe
Authors: Edie John W. , Boyer Daniel B. , Kai Chiu Chan
Published: November 2010

The phase distributions of several dental amalgams have been determined by two methods: calculation from elemental analysis data obtained with the microprobe, and measurement of phase areas on backscattered electron photographs with the image analyzer. The results of these methods agree, in general, with the distributions predicted by the stoichiometric equations.
Fluorine and Tin Uptake by Enamel Studied by X-Ray Photoelectron Spectroscopy (ESCA)
Authors: Hercules David M. , Craig Norman L.
Published: November 2010

ESCA has been combined with argon-ion etching to obtain depth profiles for SnF2treated enamel. Three zones of products from the topical treatment are detected: a layer of tin oxide on the surface; fluoroapatite + hydroxyapatite at depths below about 0.2 micron; an intermediate layer CaF2, Sn(OH)2, Sn2 PO4 OH, and fluoroapatite between the two. Sn3F3PO4 was not detected.
Collagen Metabolism in Skin and Periodontal Ligament of Rats: Effect of Aging and Irradiation
Authors: Skougaard M.R. , Carsten A.L.
Published: November 2010

Sixty rats were sacrificed 2, 7, and 21 days after 3H-proline injection; 30 were irradiated with fast neutrons. Half of the rats were sacrificed 30 to 49 days after time of irradiation, the remaining 30 one year later. The3 H-activity per mg dry weight as well as the3 H-hydroxyproline activity in the skin was assayed. Furthermore, the autoradiographic grain count per unit area periodontal ligament was estimated. The irradiated rats lost weight during the first days but started to gain weight 14 days after irradiation. In the young irradiated rats, the3 H-HP activity in skin was depressed at 2 and 7 days after injection but reached the same level as the controls after 21 days, indicating a delay in the hydroxylation of Proline. The old controls had a lower3 H-HP level than the young controls, whereas no activity was found in the skin of the old irradiated rats. In periodontal ligament, grain counts revealed a decrease in the uptake of labeled amino acid in the young irradiated animals; the rats had, however, recovered their ability to incorporate labeled proline in the perzodontal ligament one year after irradiation. The fact that the level of activity was the same in the old irradiated rats as in the controls suggested that the rats had regained the ability to anabolize collagen in the periodontal ligament.
The Aymara of Western Bolivia: III. Occlusion, Pathology, and Characteristics of the Dentition
Authors: Palomino Hernan
Published: November 2010

With the objective of contributing to the understanding of factors influencing the characteristics of dentition, dental observations from 429 children and adult highland people of western Bolivia are described. Various age, sex, ethnic, and village differences are observed in malocclusion, dental caries, periodontal disease, dental morphology, and anomalies. The findings revealed a population with relatively good occlusion, low frequency of dental pathology, and dental characteristics in part consistent with those of other similar Amerindian populations.
Wet Weights of Dental Plaques
Authors: Gilmour M.N. , Zahn L.B. , Turner G.
Published: November 2010

A method for weighing samples of plaque using a weighing assembly comprising a sample-bearing boat, held in a closed capsule to avoid moisture loss to room or balance environment is described. The system described is an objective device for measuring, by wet weight the amounts of plaque accumulating under various conditions of oral hygiene.
Psychological Characteristics of Long-Term Female Temporomandibular Joint Pain Patients
Authors: Gale Elliot N.
Published: November 2010

Analysis from the Taylor Manifest Anxiety Scale (TMAS) scores of 44 long-term temporomandibular joint (TMJ) pain patients and 10 facial pain patients of a non-TMJ variety shows no significant differences. Both groups were significantly higher than a normative group. After treatment TMJ patients are not significantly different on the TMAS than the normative group. Etiological implications are discussed.
Polyurethane Elastomers as Maxillofacial Prosthetic Materials
Authors: Goldberg A. Jon , Craig Robert G. , Filisko Frank E.
Published: November 2010

A series of polyurethane elastomers based on an aliphatic diisocyanate and a polyether macroglycol was polymerized with various crosslink densities and OH/NCO ratios. Stoichiometries yielding between 8,600 and 12,900 gm/ mole/crosslink and an OH/NCO ratio of 1.1 resulted in polymers with the low modulus, yet high strength and elongation necessary for maxillofacial applications.
Relaxation of Orthodontic Elastomeric Chains and Modules In Vitro and In Vivo
Authors: Ash J.L. , Nikolai R.J.
Published: November 2010

Relaxation patterns for two orthodontic polyurethane-based elastics have been quantified in dry air and water bath environments and in vivo. Water bath simulation of in vivo behavior is apparently valid for up to a week following initial activation, but it becomes somewhat erroneous thereafter.
An In Vitro Investigation of the Penetrating Efficacy of BIS-GMA Resin Pit and Fissure Coatings
Authors: Powell Keith R. , Craig Graham G.
Published: November 2010

The frequency of complete penetration of two commercial BIS-GMA resin pit and fissure coating materials into wide and constricted fissures was assessed from photomicrographs. It was found that 334 of the 390 wide fissures examined were completely filled by the coating materials. However, in contrast, only 28 of the 650 constricted fissures examined were completely filled by these resins.
Clinical Study of Dental Cements. VII. A Study of Bridge Retainers Luted with Three Different Dental Cements
Authors: Silvey Ralph G. , Myers George E.
Published: November 2010

In a clinical study of three luting cements, 547 bridges and 162 crowns were permanently cemented. Patients were recalled at 6-month intervals and the restorations were examined for looseness. A pattern of retainer type, cement type and retainer success was demonstrable.
Phospholipids of a Bone Matrix Calcification Nucleator
Authors: Ennever J. , Vogel James J. , Riggan Linda J.
Published: November 2010

Phospholipids of a bone matrix calcification nucleator wre identified as mono-and diphosphoinositides and phosphatidyl serine. The nucleator, a protein-phospholipid complex, was dissociated by acidified-solvent porous-glass column chromatography. Analysis was by gas-liquid chromatography.
Semiconductor Probe Measurements in Beagle Pups during Deciduous Tooth Development
Authors: Jeffcoat M.K. , Kaplan M.L. , Weinstein M. , Goldhaber P.
Published: November 2010

Bone-seeking radio pharmaceuticals were used together with clinical and radiographic procedures to study tooth development in dogs. Similarities in the pattern and time course of radiopharmaceutical uptake in jaw areas studied suggest that changes in alveolar bone metabolism are not closely related to eruption times of individual teeth.
A Study of High Copper Amalgams. I. A Comparison of Amalgamation on High Copper Alloy Tablets
Authors: Okabe T. , Mitchell R. , Butts M.B. , Wright A.H. , Fairhurst C.W.
Published: November 2010

Two types of high copper alloy powder have been amalgamated by plating tablets of compacted powder with Hg. γ1 Ag-Hg crystals form on both types of tablet. On one type, η Cu-Sn crystals are also formed. An amalgamation mechanism for this latter type of high copper amalgam is discussed.
Activation of Latent Collagenase of Human Leukocytes and Gingival Fluid by Bacterial Plaque
Authors: Uitto Veli-Jukka , Raeste Anna-Maija
Published: November 2010

Collagenase activity was studied in human leukocytes, gingival crevicular fluid and bacterial plaque, with soluble radioactive collagen as substrate. Inflamed gingiva liberated vertebrate type collagenase into the crevicular fluid in active form. Healthy gingiva, in contrast, released collagenase in a latent form that could be activated by trypsin or plaque. Plaque also stimulated leukocytes to release collagenase, and activated the latent enzyme.
Color Stability of Elastomers for Maxillofacial Appliances
Authors: Craig R.G. , Koran A. , Yu R. , Spencer J.
Published: November 2010

The color stability of polyvinyl chloride, polyurethane, and silicone polymers for maxillofacial applications was determined after accelerated aging using reflectance spectrophotometry. On the basis of color stability after accelerated aging, and ease of processing, several silicone materials were the most promising.
Optimizing Creep and Corrosion Properties in a Dispersant Amalgam Using Manganese
Authors: Waterstrat R.M.
Published: November 2010

It is shown that the creep behavior of a commercial dispersant-amalgam containing copper is improved by the addition of a manganese-containing alloy. This improvement is apparently obtained without any serious changes in corrosion resistance, provided that no more than 20% of the Mn alloy is added.
Parameters that Affect the Color of Direct Restorative Resins
Authors: Powers John M. , Dennison Joseph B. , Lepeak Patrick J.
Published: November 2010

The effects of thickness, background color, specular reflection, and surface roughness on the color of five commercial restorative resins were studied by reflection spectrophotometry. As thickness increased, values of luminous reflectance and excitation purity increased for a black background but decreased for a white background. Opacity increased dramatically as thickness increased from 1.3 to 3.9 mm.
A Technique for the Removal of Junctional Epithelium from the Epithelial Attachment
Authors: Buchanan William , Bernard George W.
Published: November 2010

A technique utilizing sodium deoxycholate to remove junctional epithelial cells from the epithelial attachment zone is described. Light and electron micragrayhs show a simalarity in size and appearance between the extracetlutar attachment substance in controls and the extracellular substance which remains on cementurn previously in contact with junctional epithelium.
Fluoride Uptake and Dissolution Behavior of a Synthetic Dental Enamel - like Substrate
Authors: Jarcho M. , Dombrowski L.J. , Salsbury R.L. , Bondley B.A.
Published: November 2010

A new ceramic form of hydroxylapatite and enamel were found to behave similarly in regard to their acid dissolution behavior in the presence and absence of topically applied fluoride. Discrepancies between the two materials can be explained by morphological differences between the rough enamel and smooth ceramic particles.
Microscopic Assay for the Phagocytotic-Collagenolytic Performance (PCP Index) of Human Gingival Fibroblasts in vitro
Authors: Rose George G. , Yajima Toshihiko , Mahan Charles J.
Published: November 2010

Using 16 human gingival fibroblast cell lines from patients with periodontitis, Dilantin hyperplasia, and nonpathological gingiva, a microscopic assay was developed to quantitate the cells' ability to lyse collagen substrates. The method employs tissue culture chambers with one cover slip partially coated with a thin layer of undenatured fibrillar bovine codlagen. The assay measures the relative numbers and sizes of holes in the collagen within defined regions of the cover slips effected by the phagocytotic and collagenolytic performance (PCP) of the population of fibroblasts growing on the cover slip for 5 days. The effect on the PCP index by serum, heparin, prostaglandins, and endotoxin was evaluated.
Non-Specific Induction of Mineralization of Incisor Pulp in the Rat
Authors: Matena V. , Plačková A.
Published: November 2010

Mineralized intrapulpal lesions were readily formed in the rat incisor after a single intrapulpal injection of the calcergen potassium permanganate, as well as after saline. Besides that there occurred irregular secondary dentin apposition and hard tissue over-bridging at the injection site. The mechanism of topical calcinosis in relation to pulp tissue was discussed.
The Effect of Eugenol on Oral Mucous Membranes
Authors: Kozam George , Mantell Gary M.
Published: November 2010

Eugenol, in the 100 percent concentration in commercial use, was applied to a circumscribed area, 3 mm in diameter, of rat labial mucosa for 1 minute. Reaction periods of 15 minutes, 1, 2, 4 and 6 hours were then permitted. Using routine histological procedures for processing the experimental tissues, it was observed that eugenol caused denaturation of cytoplasmic proteins and loss of staining capacity of epithelium, loss of cell boundaries, swelling and cell necrosis. In addition, vesicle formation, edema in the corium, and striated muscle dissolution were observed.
Color Stability of Restorative Resins Under Accelerated Aging
Authors: Powers John M. , Dennison Joseph B. , Koran Andrew
Published: November 2010

The color stability of seven commercial composite resins, an unfilled resin, and three glazes was studied under conditions of accelerated aging by reflection spectrophotometry and visually with Munsell color tabs. After aging for 900 hours, most of the resins had lower values of luminous reflectance and excitation purity and higher values of dominant wavelength and contrast ratio compared to values at baseline.
Role of cGMP in Isolated Rat Parotid Acinar Cells
Authors: Mangos J.A.
Published: November 2010

The role of cGMP as the intracellular mediator of the activation of cholinergic receptors in the secretory cells of the rat parotid gland was investigated in vitro using isolated rat parotid acinar cells. It was demonstrated that this cyclic nucleotide is involved in the intracellular translation of activation of muscarinic cholinergic receptors in these cells.
The Colorimetric Analysis of Sialic Acid in Human Saliva and Bovine Salivary Mucin
Authors: Pearce E.I.F. , Major G.N.
Published: November 2010

Three colorimetric methods were compared for their suitability for the analysis of sialic acid in human mixed saliva and bovine submaxillary gland mucin. The thiobarbituric acid method was most precise with human saliva, appeared to be subject to the least interference and is therefore the method of choice for these samples. However, it is not possible to use this method for the analysis of bovine mucins. With these samples the resorcinol method was most suitable, being subject to the least interference and relatively precise. The direct Ehrlich method was least precise overall and gave high values with human whole saliva.
A Preliminary Scanning Electron Microscope Examination of Wear Striation Direction on Primate Teeth
Authors: Ryan Alan S.
Published: November 2010

Wear striations experimentally produced on initially unworn teeth were examined at high magnification using a scanning electron microscope. Certain characteristics of individual wear striations on these teeth indicate the direction of motion that produced them. Other striations on worn teeth of American Indians and the Paleocene primate Phenocolemur show similar characteristics and correspond to mandibular movement during mastication.
Orogranulocyte Peroxidase Activity as a Measure of Inflammatory Periodontal Disease
Authors: Klinkhamer James M. , Mitchell Marcella D.
Published: November 2010

Benzidine dihydrochloride in the presence of dimethylsulfoxide reacts with myeloperoxidase contained within the granules of polymorphonuclear leukocytes obtained from the oral cavity. A blue meriquinoid oxidation product is formed in the presence of hydrogen peroxide, which can be extracted from the granules with a combination of methyl alcohol and dimethylsulfoxide. A stable yellow-brown pigment is formed which can be measured spectrophotometrically. The values are expressed in optical density units and correlate with the Orogranulocytic Migratory Rate units obtained by other means. Consequently, the spectrophotometric method is an additional non-subjective technique available for the evaluation, monitoring, and indexing of inflammatory periodontal disease.
Ultrastructural Study of the Protein-Polysaccharides Distribution in Enamel from Rat Incisors
Authors: Goldberg M. , Genotelle-Septier D. , Weill R.
Published: November 2010

The distribution pattern of the protein-polysaccharides in the rat incisor enamel was similar whether stained for glycoproteins (phosphotungstic acid) or for proteoglycans (alcian blue, bismith nitrate). Except for the holes at the dentino-enamel junction, where these components seem to exist as amorphous gel, protein-polysaccharides are closely associated to the proteinic fibrous matrix in rods and interrods structures as in prism sheaths where they are particularly abundant.
An Antisera for the Fluorescent Labeling of Mouse Amelogenesis
Authors: Hyatt-Fischer H. , Chrispens J. , O'Keefe D. , Slavkin H.C.
Published: November 2010

Embryonic mammalian enamel extracellular matrix is immunogenic. Antisera has been produced in New Zealand white rabbits using 5-day-old (postnatal) C57B1/6J mandibular and maxillary incisor and molar tooth organs as immunogens. The expression of secretory amelogenesis in mouse molar tooth organs was studied from the "cap stage" (circa 17-day fetus) to the fifth day of postnatal odontogenesis using indirect immunofluorescent microscopy. The specificity of the antisera for enamel matrix secretion was unequivocal. Secretory amelogenesis was observed in molar tooth organs as early as day-2 postnatal age. These reagents and methods provide a significant strategy in studies of epithelial-mesenchymal interactions during tooth development.
Titanium and Fluoride Concentrations in Titanium Tetrafluoride and APF Treated Enamel
Authors: Clarkson Brian , Wefel James
Published: November 2010

Greater fluoride concentrations were obtained in enamel treated with phosphate/fluoride solutions than in that treated with TiF4 at similar pH's (1.0) and F concentrations (0.6M F and 1.6M F). However, fluoride solution without added phosphate at pH 1.0 and 1.6M F concentration produced lower fluoride concentrations in enamel than in TiF4 treated enamel. It is proposed that in TiF4 treated enamel the fluoride uptake may be dependent upon the amount of Ti introduced into the enamel.
Inter-examiner Reliability in Caries Trials
Authors: Fleiss Joseph L. , Slakter Malcolm J. , Fischman Stuart L. , Park Molly H. , Chilton Neal W.
Published: November 2010

A statistical model is given for representing the several components of variability present in measurements (e.g., DMFS scores) given by examiners to patients. Methods for making inferences about the intraclass correlation coefficient of reliability are presented and illustrated on a real set of data. The proper analysis of data from a reliability study is shown to depend on the planned design and analysis of the clinical or field trial to be conducted following the reliability trial.
Effects of Sequential Calcium Phosphate- Fluoride Rinses on Fluoride Uptake in Rats
Authors: Shern R.J. , Couet K.M. , Chow L.C. , Brown W.E.
Published: November 2010

This study measured the effects of a calcium phosphate rinse followed by various fluoride rinses on fluoride uptake by enamel in rats. Calcium phosphate rinses promoted fluoride uptake by the enamel.
Comparative Histology of Progressive Mineralization Pattern of Developing Incisor Enamel of Rodents
Authors: Suga S.
Published: November 2010

The progressive mineralization pattern of developing incisor enamel of rodents, (rats, bankvoles, mastomises and hamsters) was studied from the viewpoint of comparative histology.
A Non-Destructive Optical Method to Study De- and Remineralization of Enamel
Authors: Ten Bosch J.J. , Borsboom P.C.F. , Ten Cate J.M.
Published: November 2010

The absorption and scattering of light in dental enamel or in a carious lesion have been studied quantitatively by using thin slabsl. The method thus required destructive preparation techniques. In this paper we describe how the scattering by a bulk sample can be used to obtain semi-quantitative information.
A Simple Ultrasound Method to Characterize in vitro Plaque Inhibition Activity
Authors: Lim J.K. , Yong C.L. , Gerencser V.F.
Published: November 2010

A method employing ultrasound vibration for evaluating in vitro plaque derived from streptococcus mutans was developed. It successfully detected small changes in the cohesive/adhesive characteristics of deposits briefly exposed to several antibacterials and "antiadherents". Increased structural fragility and diminished plaque growth were generally associated with the antibacterials.
Human Dentition and Experimental Animals
Authors: Fejerskov O.
Published: November 2010

A review of the recent literature concerning enamel maturation patterns following cessation of protein matrix secretion confirms that developing rodent enamel exhibits an overall mineral distribution different from that of developing enamel in man, monkey, dog, and swine. This seems to be a result of structural differences of the enamel as the pattern of crystal growth appears similar in these species. Whether the differences in enamel structure are reflected in significant differences in cellular events leading to enamel formation and mineralization remain unknown, as detailed radio-autographic and ultrastructural studies almost always have dealt with rodent teeth. It is therefore concluded that such studies should be initiated in experimental animals having an enamel formation and mineralization pattern strictly comparable to that of man. Some requirements for such an experimental animal are suggested.
Enamel Proteins: Biosynthesis and Chemistry
Authors: Sasaki S. , Shimokawa H.
Published: November 2010

Bovine ameloblast cell layer was incubated in 3H-proline containing medium and the incorporation of radioactivity into protein fractions of the cell and the medium was investigated by SDSpolyacrylamide gel electrophoresis.

The results suggest that the ameloblasts synthesize and secrete a protein having a molecular weight of 25,000 daltons which is supposed to be the prototype of enamel proteins. This protein was degraded into dialyzable sizes by the cell extract. After a longer period of incubation another low molecular weight protein fraction appeared in the medium.

Purification procedure with SDS gel filtration of the enamel protein is reported.
Phosphopeptides of Enamel Matrix
Authors: Glimcher M.J.
Published: November 2010

Although the tripeptides Glu-O-Phosphoserine-Tyr and Glu-O-Phosphoserine-Leu have been identified in embryonic bovine enamel proteins,1,2 the issue of whether both sequences occur in each of the phosphopeptides, or whether certain sequences occur in specific peptides only, has recently been resolved by isolating homogeneous samples of E33 and E44. All three of the Ser residues of both peptides are phosphorylated. All three in E3 are in the sequence Glu-O-Phosphoserine-Leu, and all three in E4 are in the sequence Glu-O-Phosphoserine-Tyr. It was not possible to sequence either of the polypeptide chains directly by automatic peptide sequencing. However, a partial sequence of E4 was constructed from data derived from peptides isolated after cyanogen bromide, trypsin and chymotrypsin digestions. The presence of Glu, Tyr and Leu adjacent to and near the O-Phosphoserine [Ser(L)] residues and the 2°, 3° and higher ordered structures of the enamel phosphopeptides may be important in calcium binding and mineralization.
Dentin Proteins: Chemistry, Structure and Biosynthesis
Authors: Butler W.T. , Munksgaard E.C. , Richardson W.S.
Published: November 2010

One of the most abundant noncollagenous proteins of dentin is a phosphoprotein rich in aspartic acid and phosphoserine. This protein occurs in soluble and inextractable forms, the latter being associated with the insoluble collagenous matrix. This protein is capable of tightly binding a relatively high level of calcium. Biosynthetic and radioautographic data suggest that shortly after its biosynthesis, the phosphoprotein is transported and bound to the collagen at the predentin-dentin junction. This event is probably central to the mineralization process, though other glycoproteins may be involved.
Ultrastructural Studies of Enamel Crystallites
Authors: Kerebel B. , Daculsi G. , Kerebel L.M.
Published: November 2010

High resolution electron microscopy has provided precise measurements of human enamel crystallites from the first stages of enamel development to the last stage of maturation, through counting of lattice planes and statistical analysis. Thickness and width measurements of human enamel crystallites in their mature stage are 263 Å (21.9 standard error) and 683 Å (134 standard error), respectively. The growth curve of enamel crystallites was drawn, the increase in the number of lattice planes in the course of enamel development was demonstrated. Fusions and dislocations related to the maturation process were visualized and discussed. Difficulties linked to the use of ultrastructural techniques were mentioned. The question of the organic stroma of the crystals remained unsettled.
Enamel Apatite Nucleation and Crystal Growth
Authors: Nancollas G.H.
Published: November 2010

The course of enamel remineralization in aqueous solution is markedly dependent upon factors such as ionic medium supersaturation, pH, ionic strength, and the relative concentration of mineralizing surface. Although numerous attempts have been made to determine the mechanism of both the spontaneous and seeded precipitation reactions, it is only recently, through the use of a constant solution composition technique, that quantitative information can be obtained concerning the intermediate calcium phosphate phases which are formed during mineralization. Studies of surface phases in the presence of potential anti-calculus and anti-caries agents are facilitated using this approach.
Demineralization and Remineralization of Dental Enamel _____
Authors: Moreno E.C. , Zahradnik R.T.
Published: November 2010

Experimentation in vitro using organic acid buffers as demineralizing media shows that caries-like lesions can be obtained which are very similar in morphology and developmental stages to early lesions formed naturally under oral conditions. The use of these chemical systems and of mechanistic models advanced to explain the unique histological features of incipient caries have yielded a good understanding of the processes involved in caries formation. The study of natural and induced factors influencing the demineralization process has been greatly facilitated by the use of bacteriological systems in which demineralization is produced by direct colonization of cariogenic microorganisms on the surfaces of extracted teeth. Comparison of results obtained with these latter systems and with chemical systems has allowed us, for example, to elucidate the mechanism by which acquired salivary pellicles and fluoride topical solutions decrease the rate of enamel demineralization. The pellicle retards transport of matter across the enamel surface, whereas the fluoride topical solutions decrease the cariogenicity of the colonizing bacteria.
Dental Enamel Matrix — Isolation and Partial Sequence of a Peptide Component
Authors: Fincham A.G.
Published: November 2010

Chromatography of demineralized bovine fetal enamel matrix proteins on 'Biogel P6' was shown to yield a trailing peak which contained a single electrophoretic component. This polypeptide, further purified by chromatography on Biogel P4', was found to be homogeneous by disc electrophoresis and gel isoelectric focussing. Amino acid analyses indicated this component (designated: 'E5') to be similar to some of the phosphopeptides previously described. Cyanogen bromide cleavage of E5 yielded three principal products whose amino acid compositions and N-terminal residues were investigated. A partial sequence for component E5 was proposed and comparison with previous bovine matrix isolates was made.
The Effect of Protein-Energy Malnutrition on the Growth of Tooth Germs in Newborn Rats
Authors: Nakamoto Tetsuo , Mallak Henry M. , Miller Sanford A.
Published: November 2010

The effect of protein-energy malnutrition on the growth of molar and incisor tooth germs was studied. Significant differences were found between control and malnourished groups in the weights and calcium contents of both tooth germs. The data point to the importance of the effect of nutrient deficiency on the critical growth period of an oral structure.
Influence of Lithium Upon Dental Caries in the Rat
Authors: Olson Byron L. , McDonald James L. , Stookey George K.
Published: November 2010

Two studies were performed on rats to determine the post-eruptive cariostatic effects of lithium alone and in combination with fluoride. The results failed to demonstrate any cariostatic effects of lithium when evaluated in this manner, nor any enhancement by lithium of the cariostatic activity of fluoride.
The Fate of Amalgam Implanted in Soft Tissues- An Experimental Study
Authors: Eley Barry M.
Published: November 2010

The soft tissue reaction to amalgam depended on whether it was finely ground or a solid mass. Finely ground amalgam was actively digested within macrophages and giant-cells with loss of mercury and the formation of fine particles of silver and sulphur. Larger masses became surrounded by a fibrous capsule.
Electrophoretic Patterns of Proteins from the Dentary, Vertebra and Scale in the Ayu Fish, Plecoglossus altivelis, Temminck et Schlegel
Authors: Komada Noritomo , Katsukawa Hideo
Published: November 2010

The electrophoretic patterns of the proteins extracted from dentary, vertebra and scale with the phosphate buffer, 0.1 NHcl and SDS solution were studied to investigate their molecular aspects. The banding patterns and relative amounts of the proteins from dentary, vertebra and scale showed a basic similarity.
Suppression of Streptococcus mutans in the Mouths of Humans by a Dental Prophylaxis and Topically-applied Iodine
Authors: Caufield P.W. , Gibbons R.J.
Published: November 2010

A prophylaxis followed by three topical applications of an iodine-potassium iodide solution significantly reduced the levels of Streptococcus mutans in fissure and approximal plaques and in saliva. Reductions persisted 20-24 weeks after treatment in salivary and approximal samples. A prophylaxis alone exerted a small and temporary reduction of S. mutans in occlusal fissure plaque, but did not reduce the levels of this organism in approximal plaque or in saliva. A significant relationship existed between the levels of S. mutans in saliva and the proportions of this organism in plaque. The dorsum of the tongue does not appear to constitute a significant reservoir for S. mutans following disinfecting procedures.
Evaluating Dimensional Accuracy of Stone Models
Authors: Hosoda Hiroy Asu , Ohsawa Masahiro
Published: November 2010

An optical feeler measuring technique was introduced for evaluating the dimensional accuracy of indirect stone models. It presents the following advantages: being able to measure the diameter of specimens in detail at various heights, indicating good reproducibility of the data; and hardly in juring the surface of the stone casts.
Modifying the Setting Rate of an Addition-Type Silicone Impression Material
Authors: Stannard J.G. , Craig R.G.
Published: November 2010

Two methods for controlling the working time of an addition-type silicone impression material are presented. The progress of the polymerization reaction of this modified system was studied using viscosity and a new "compression set" technique. The physical properties are presented and compared to those typical of condensation silicones, and a method of clinical use is suggested.
The Role of Diffusible Ionic Species in the Bonding of Polycarboxylate Cements to Dentine: An in vitro Study
Authors: Causton B.E. , Johnson N.W.
Published: November 2010

Treatment of freshly-cut dentine with fluoride ions or high concentrations of metal ions produced changes ranging from mineralization of tubule contents to precipitation of adherent surface layers. Combinations of these treatments with application of fluoridated and non-fluoridated polycarboxylate cements and glass ionomer cements produced both increases and reductions in bond strength which are explained by ionic diffusion at the interface prior to setting.
Relation Between Integrated Electromyographic Activity and Biting Force During Voluntary Isometric Contraction in Human Masticatory Muscles
Authors: Kawazoe Yasuyuki , Kotani Hiroo , Hamada Taizo
Published: November 2010

The relation between integrated electromyographic activity and computed biting force during voluntary isometric contraction was evaluated in the masticatory muscles of healthy subjects. The slopes of the curves relating integrated electromyographic activity to computed biting force in masseter muscles were steeper on the non-preferred chewing side than on the preferred chewing side, and they progressively became steeper during the course of continuous isometric contraction of a given biting force.
Color Stability of a Pigmented Elastomer for Maxillofacial Appliances
Authors: Koran Andrew , Yu Robert , Powers John M. , Craig Robert G.
Published: November 2010

The color stability of a series of eleven maxillofacial pigments was determined after accelerated aging using reflection spectrophotometry. The results indicate that seven of the pigments demonstrated good to excellent color stability, while four of the pigments were less promising for clinical use.
A Method for Detection of Complement Cleavage in Gingival Fluid
Authors: Patters Mark R. , Schenkein Harvey A. , Weinstein Arthur
Published: November 2010

A sensitive method is described for detection of C3 cleavage in gingival fluid taken from sites of both normal and inflamed gingiva. Preliminary data suggest a direct relationship between C3 conversion and the presence of periodontal disease.