Journal of Dental Research

Calhoon, D.A.; Mayberry, W.R.; Slots, J.

doi: 10.1177/00220345830620120101pmid: 6581193

We compared the cellular fatty acid and protein content of 43 strains of oral fusobacteria isolated from patients with chronic gingivitis, acute necrotizing ulcerative gingivitis, and juvenile and adult periodontitis, as well as from the stump-tailed macaque, to that of eight reference strains of oral and non-oral Fusobacterium species. A gas-liquid chromatographic examination of trimethylsilyl derivatives of the fatty acid methyl esters revealed n14:0, 3-OH-14:0, n16:0, 16 :1, 3-OH-16:0, n18:0, and 18:1 in each of the 51 study strains, and a variable occurrence of 14 other fatty acids. The n16:0 to 3-OH-16:0 ratio distinguished between Fusobacterium nucleatum and the non-oral species Fusobacterium varium, Fuso bacterium necrophorum, Fusobacterium russii, Fusobacterium necrogenes, Fusobacterium mortiferum, and Fusobacterium naviforme. The soluble protein content, as determined by polyacrylamide gel electrophoresis, varied considerably among the oral fusobacterial strains studied, and underscored the heterogenous nature of these organisms. "Fingerprinting" of oral fusobacteria may be readily accomplished by polypeptide analysis.

Bolton, R.W.; Dyer, J.K.; Reinhardt, R.A.; Okano, D.K.

doi: 10.1177/00220345830620120201pmid: 6581194

An exopolysaccharide (EP), purified from spent culture fluid previously inoculated with Capnocytophaga ochracea strain 25, suppressed in vitro human peripheral blood lymphocyte responses to the mitogen concanavalin A. EP was suppressive when added to cultures before the mitogen, but enhanced responses when added 24 or 48 hr after the mitogen.

Biltz, R.M.; Pellegrino, E.D.

doi: 10.1177/00220345830620120301pmid: 6581195

Bone mineral and synthetic calcium-deficient carbonate apatite (CDCA), when defined in terms of their respective thermal stabilities and ignition products, are homologous. When heated to 550°, they may have a structure similar to that of the mineral dahllite. When heated to temperatures >550°, CDCA (like bone mineral) loses its structural CO3 and is recrystallized to whitlockite and/or OH-apatite, depending on its stoichiometry.

Ericsson, Y.; Angmar-Mansson, B.

doi: 10.1177/00220345830620120401pmid: 6581196

Alkaline and acid phosphatases (p-ases), fluoride (F), and calcium (Ca) were analyzed in the pulps of rat incisors and young human pre-molars. P-ase activities were about ten times higher in the rat than in the human pulps; in the latter, high p-ase activity appeared to be connected with rapid mineralization. Average total F was 3-4 ng/mg in both rat and human pulp, while Ca showed values several times higher, although greatly varying, in human than in rat pulps. Ionized F was two to three times higher in ultrafiltrates from rat and human pulps than in the blood plasma of the species; in the rat, the F content of the ultrafiltrates increased only three to four times when plasma F was experimentally elevated over 100 times. In vitro, rat pulp alk. p-ase activity was slightly inhibited only in the range above 100 mM NaF, while acid p-ase showed weak inhibition in the region from 0.15-0.25 mM and 40-60% inhibition in the range from 10-100 mM NaF. In vivo, no effect on pulp p-ases was found, even from sublethal NaF doses.

Nelson, D.G.A.; Jongebloed, W.L.; Arends, J.

doi: 10.1177/00220345830620120501pmid: 6581197

Three topical fluoride agents deposited surface coatings of different morphology and thickness on intact human enamel surfaces. The agents studied were an acidic silane fluoride lacquer, a neutral NaF lacquer, and an APF gel. Each agent reacted with the enamel surface differently, producing its own distinctive etching pattern. The smallest particles observed in the surface coatings were from 20 to 30 nm in diameter and appeared to have indistinct morphologies. They often agglomerated into spherical globules ranging from 1-3 μm in diameter.

Mattingly, J.A.; Sauer, G.J.; Yancey, J.M.; Arnold, R.R.

doi: 10.1177/00220345830620120601pmid: 6361082

Patients undergoing orthodontic therapy were evaluated for longitudinal changes in relative S. mutans numbers in plaque at discrete sites on the tooth surface associated with direct bond appliances. There was a significant linear increase in the percentage of S. mutans in the total streptococci isolated from the last pre-bracket sample through the last bracket sample.

Steflik, D.E.; McKinney, R.V.; Koth, D.L.

doi: 10.1177/00220345830620120701pmid: 6361083

A statistical analysis was carried out an the clinical evaluatory data gathered from a two-year longitudinal study of the single-crystal sapphire endosteal dental implant in dog jaws. Statistically, the implants behaved either better than control molars (clinically), or in a manner similar to control molars. These data suggest an excellent prognosis for the single-crystal sapphire dental implant.

Tehrani, A.; Brudevold, F.; Attarzadeh, F.; Van Houte, J.; Russo, J.

doi: 10.1177/00220345830620120801pmid: 6581198

Intra-oral enamel demineralization tests, involving rinsing with sucrose solutions (5, 1, 0.5, or 0.3%) at varying frequencies during a 1.5-hour period, showed that demineralization was a function of the total sugar dose (frequency of rinsing times concentration). Two rinses with a 5% solution caused demineralization, nine rinses were needed in the case of a 0.5% solution, and none occurred after nine rinses with a 0.3% solution. Remineralization was also observed and apparently occurred after exhaustion of the sucrose supply.

Brudevold, F.; Tehrani, A.; Attarzadeh, F.; Van Houte, J.; Russo, J.

doi: 10.1177/00220345830620120901pmid: 6581199

Mouthrinses with 5% solutions of different sugars were tested for their demineralizing effect on blocks of bovine enamel covered with a layer of S. mutans cells and carried in a palatal prosthesis. The extent of demineralization, as measured by the permeability of the enamel to iodide, was similar for fructose, glucose, and sucrose, less for maltose and lactose, and least for galactose.

Johnson, D.L.; Rinne, V.W.; Bleich, L.L.

doi: 10.1177/00220345830620121001pmid: 6361084

Based on polarization measurements, high Au alloys are highly corrosion-resistant and exhibit the lowest corrosion rates; intermediate Au, Ag, and Pd alloys with Cu are passive but exhibit higher corrosion rates. Twenty weight percent (w/o) In-Ag alloys exhibit active corrosion behavior at potentials only 100 m V noble to the corrosion potential.