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Biomedical subjects

A Gaffar

Publications and source records attributed to A Gaffar.

At least 55 records · Page 3Linked to original sources
PubMed1990

Comparative anticalculus effect of dentifrices containing 1.30% soluble pyrophosphate with and without a copolymer.

A six-month, double blind, clinical study was conducted to determine the effect on supragingival calculus formation of a dentifrice containing 1.30% soluble pyrophosphate (from 2.0% tetrasodium pyrophosphate) and 1.50% of a copolymer of methoxyethylene and maleic acid, as compared to a dentifrice containing the same amount of soluble pyrophosphate but without the copolymer. This pyrophosphate/copolymer dentifrice contained the optimal ratio of pyrophosphate anion to copolymer required for obtaining a comparable anticalculus effect to a clinically proven anticalculus dentifrice containing 3.3% soluble pyrophosphate and 1.0% of a copolymer. The optimal pyrophosphate/copolymer ratio was determined by a series of in vitro laboratory and in vivo animal studies. Male and female adult subjects were stratified into three balanced groups according to baseline calculus scores. They received an oral prophylaxis and were assigned to the use of either the dentifrice containing soluble pyrophosphate and the copolymer, or to the dentifrice containing soluble pyrophosphate but without the copolymer, or to a placebo dentifrice that did not contain an anticalculus ingredient. The results of the three-month calculus examination indicated that the dentifrice containing soluble pyrophosphate and the copolymer provided a 33.66% reduction in supragingival calculus formation after an oral prophylaxis as compared to the placebo dentifrice. This reduction was statistically significant at the 99 percent level of confidence. The results of the six-month calculus examination indicated that the dentifrice containing the soluble pyrophosphate and the copolymer provided a 36.10% reduction in supragingival calculus formation after an oral prophylaxis, as compared to the placebo dentifrice. This reduction was also statistically significant at the 99% level of confidence.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

In vitro antiplaque effects of a triclosan/copolymer mouthrinse.

The influence of a mouthrinse containing 0.03% triclosan (2,4,4'-trichloro-2'-hydroxydiphenyl ether) and 0.25% copolymer (polyvinylmethylether maleic acid copolymer), compared to a matching placebo rinse, on in vitro plaque formation was assessed in two dynamic plaque model systems. In the controlled saliva flow cell system, the triclosan-containing rinses significantly reduced total plaque compared to the placebo rinse, with no significant differences when copolymer was removed from the active rinse formula. In the continuous culture system (chemostat flow cell model), the mean plaque was significantly reduced when compared with placebo. The results of these studies indicate that a triclosan mouthrinse, in the presence or absence of copolymer, is effective in reducing plaque in vitro.

Bacteria↗
PubMed1990

Antiplaque effects of dentifrices containing triclosan/copolymer/NaF system versus triclosan dentifrices without the copolymer.

A dentifrice containing triclosan/PVM/MA, Colgate Gum Protection Formula Toothpaste (GPF), was found to be highly effective against oral bacteria with minimal inhibitory concentration ranging from 0.3 to 5.35 micrograms/ml. A variety of in vitro model systems simulating oral environment were used to compare dentifrices containing triclosan/PVM/MA versus the dentifrices containing triclosan without PVM/MA, such as Crest Gum Health Toothpaste (CGH) and Neo-Mentadent P Toothpaste (N-MP). The uptake of triclosan on saliva-coated hydroxyapatite (HA) disks and buccal epithelial cells was significantly higher from the GPF versus the other dentifrices. Uptake on HA disks was 132 micrograms/disk versus 11 micrograms/disk from CGH; on buccal epithelial cells the uptake was 59 micrograms/2 x 10(5) cells with GPF versus 30.0 micrograms with CGH per same number of cells. The retained triclosan on the surfaces provided a sustained and higher antibacterial effect up to 4 hours post-treatment with GPF, but not with N-MP and CGH. In dynamic plaque model systems such as the chemostat or the controlled saliva flow system, GPF was significantly (P = 0.05) more effective than N-MP or CGH in reducing plaque thickness, protein and carbohydrate contents of plaque films. Collectively, the results of these microbiological and biochemical investigations indicate that the GPF has the potential to provide superior clinical efficacy versus the dentifrices without the copolymer.

Dental Plaque↗
PubMed1989

Effect of subgingival irrigation with tetrapotassium peroxydiphosphate on scaled and untreated periodontal pockets.

A total of 20 test and 20 control subjects completed an 8-week double blind clinical trial aimed at testing the therapeutic efficacy of a 7% tetrapotassium peroxydiphosphate (PDP) solution administered as a subgingival irrigant to scaled and untreated periodontal pockets. Each patient provided similar contralateral pockets with probing depths at base line of 5 mm or more (mean 6.25 mm). One pocket was selected at random for a thorough scaling, immediately following the base line examination (examination 1). The examination of each experimental site consisted of Plaque Index (P1I) and Gingival Index (GI) scores, probing depth (PD) and attachment level (AL) measurements (in mm), and a differential microscopic proportional count of certain subgingival bacterial morphotypes, namely coccoid cells, motile bacteria (not including spirochetes), spirochetes and all residual bacterial morphotypes. Test patients received coded irrigators containing the active ingredient PDP, while control patients received irrigators containing a placebo rinse similar to the test solution, but without PDP. The participants were instructed to irrigate the test sites twice a day. They were re-examined after four weeks (examination 2) and eight weeks (examination 3) from the base line examination. The results indicated that scaling and irrigation produced a significant decrease from the initial P1I and GI scores, and the PD and AL measurements. The proportions of coccoid cells were significantly increased, while the proportions of motile bacteria and spirochetes were significantly decreased. Irrigation of unscaled pockets resulted in a modest, but significant decrease in the P1I and GI scores.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

In vitro and in vivo studies on triclosan/PVM/MA copolymer/NaF combination as an anti-plaque agent.

A combination of triclosan, copolymer of PVM/MA and NaF has been optimized in vitro and in vivo for plaque effect. Triclosan (2, 4, 4' trichloro-2'-hydroxydiphenyl ether), a non-cationic antibacterial, was compatible with anionic surfactant, NaF and PVM/MA copolymer as evaluated by in vitro antibacterial tests. The in vitro uptake of triclosan on the saliva-coated hydroxyapatite disks, extracted human teeth and oral buccal epithelial cells was enhanced two fold in the presence of PVM/MA copolymer when compared to the uptake in the absence of the copolymer. The combination consisting of 0.3% triclosan/2% PVM/MA copolymer/1100 ppm NaF was found to be highly effective on reducing smooth and fissure caries, and plaque extent compared to to 1100 ppm/NaF by itself in rats when applied topically. The combination also showed significantly more fluoride uptake and reduction in enamel solubility than 1100 ppm/NaF. The results of these studies indicated that this optimized combination was an effective antiplaque/anticaries agent in vitro and in vivo.

Animals↗
PubMed1989

Cariostatic effects of monofluorophosphate in solutions and dentifrices in rats.

The cariostatic effectiveness of dentifrices and solutions containing sodium monofluorophosphate (MFP) was evaluated in rats. In one study using 36 CARA rats, the caries inhibiting effects of sodium fluoride and MFP solutions, at equivalent soluble fluoride concentrations (750 ppm F), were compared. Both MFP and sodium fluoride significantly (p less than 0.01) reduced smooth surface caries by 78% to 81%, respectively. No significant differences between the two treatment groups were observed. In a second study, 5 dentifrices formulated with dicalcium phosphate dihydrate (DCPD) abrasive and different amounts of MFP (0, 250, 500, 750, and 1000 ppm F) were tested for cariostatic effects in CARA rats. Compared to the control groups, the MFP/DCPD dentifrices significantly (p less than 0.01) reduced smooth surface caries incidence by 66%, 81%, 76% and 85% at the 250, 500, 750, and 1000 ppm F concentrations, respectively. In each of the studies, both enamel fluoride content and molar surface solubility were measured. A third study assessed the compatibility of MFP with different abrasives and the effect of dentifrice composition on the release of MFP from a dentifrice slurry to a saliva phase. No differences in MFP release were observed for two different silica-based formulations which differed with respect to thickener, humectants and other ingredients.

Animals↗
PubMed1989

Salivary and plaque triclosan levels after brushing with a 0.3% triclosan/copolymer/NaF dentifrice.

The concentration and elimination rate of triclosan in saliva was assessed as part of a six week clinical study which evaluated the antiplaque efficacy of a 0.3% triclosan/PVM/MA copolymer/NaF dentifrice. On day one of the study the concentration of triclosan in whole saliva was determined at various times after dentifrice use for both the triclosan/PVM/MA copolymer/NaF and placebo dentifrice groups. The results indicated that the salivary triclosan levels ranged from 19.7 micrograms/ml at 5 minutes to 1 microgram/ml at 2 hours after use of the 0.3% triclosan dentifrice. The triclosan elimination curve for saliva exhibited a mono-exponential decline with a half-life of 26 minutes. The plaque content of triclosan, one hour after dentifrice use, which was determined at the end of the study, was found to be relatively high (25 micrograms/g) compared to that seen in saliva at the same time (6.2 micrograms/ml). It was concluded that the 0.3% triclosan/PVM/MA copolymer/NaF test dentifrice provided effective delivery and bioavailability of the antiplaque agent, triclosan. This was based on the relatively high salivary and plaque triclosan levels observed and the concomitant reduction in plaque formation seen at the end of the study.

Dental Plaque↗
PubMed1986

Calculus revisited. A review.

Although there is no doubt that gingivitis can develop in the absence of supragingival calculus, it is not clear to what extent the presence of mineralized deposit enhances gingival inflammation. Partial inhibition of plaque mineralization can be accomplished by chemical agents, but there has been no demonstration in humans of a reduction in gingivitis. It remains to be established what level of inhibition (if any) is required to have more than a cosmetic effect. Since the accepted scenario is that apical growth of supragingival plaque precedes the formation of subgingival calculus, there is no longer an issue of whether subgingival calculus is the cause or the result of periodontal disease. Subgingival mineralization results from the interaction of subgingival plaque with the influx of mineral salts that is part of the serum transudate and inflammatory exudate. This chronology, however, should not be the basis for relegating calculus to the ash heap. Morphologic and analytical studies point to the porosity of calculus and retention of bacterial antigens and the presence of readily available toxic stimulators of bone resorption. When coupled with the increased build up of plaque on the surface of the calculus, the combination has the potential for extending (beyond that of plaque alone) the radius of destruction and the rate of displacement of the adjacent junctional epithelium. The centrality of thorough scaling and root planing in the successful maintenance of periodontal health supports the view that subgingival calculus contributes significantly to the chronicity and progression of the disease, even if it can no longer be considered as responsible for initiation.

Bacteria↗
PubMed1985

Nonbactericidal approach to reduce colonization of plaque microflora on teeth in vitro and in vivo.

A non-antibacterial, surface-modifying, perfluorosulfonamidoalkyl ester of phosphorous acid (PSAEP, 1) was adsorbed to saliva-coated hydroxyapatite disks in vitro. Pretreatment of saliva-coated hydroxyapatite beads with different concentrations of 1 markedly reduced the adherence of radiolabeled Streptococcus mutans or Actinomyces viscosus when compared with the buffer-treated controls. Pretreatment of the cells with the compound also significantly impaired their subsequent attachment to saliva-coated hydroxyapatite. In a low surface-to-volume ratio adsorption model, i.e., saliva-coated hydroxapatite disks, pretreatment with 1 for 1 min markedly reduced the adsorption of A. viscosus to the disks. A 1% solution applied topically twice a day significantly (alpha = 0.05) reduced S. mutans-induced smooth and fissure caries in rats. The effect of 0.05% 1 in a rinse was also evaluated on experimental gingivitis in beagle dogs for 6 weeks. A topical application twice a day significantly (alpha = 0.05) reduced plaque-induced gingivitis when compared to that achieved with the placebo. Microbial analyses of the plaque adjacent to gingiva indicated reduction in filamentous medium and large spirochetes as compared with that seen in the pretreatment phase. Collectively, the results show that it is possible to reduce dental caries and gingivitis via an interference with the specific adsorption of organisms to teeth.

Actinomyces↗
PubMed1985

Fluoride retention in clean and plaque-covered demineralized enamel in vivo after application of monofluorophosphate.

The retention of fluoride in clean and plaque-covered demineralized enamel in vivo was measured 1 wk after a single application of a MFP solution with low or high content of free fluoride. Demineralization of the enamel was induced in vivo during a 4-wk period prior to application of fluoride by applying orthodontic bands on a pair of premolars scheduled for extraction of orthodontic reasons. The band from one tooth of each pair was then removed and the tooth cleaned (clean enamel lesion). The band on the contralateral tooth (plaque-covered enamel lesion) was left in place. The MFP solutions were applied and the teeth extracted after one more week. The chemical form of fluorine in the lesions was analyzed by conventional acid etching of the enamel combined with KOH dissolution and by a nondestructive surface analysis using ESCA to detect intact monofluorophosphate ions. The ESCA measurements showed that MFP was only present in the clean enamel lesions, indicating complete hydrolysis by dental plaque. Alkali soluble fluoride could be extracted from both plaque-covered and clean enamel lesions. Conflicting results regarding the amount of fluoride uptake in the lesions were obtained with the acid etching and the ESCA technique. It was thus not clearly established whether plaque enhanced fluoride uptake in carious lesions after MFP application.

Acid Etching, Dental↗
PubMed1985

Evaluation of 2-phosphono-butane 1,2,4 tricarboxylate as a crystal growth inhibitor in vitro and in vivo.

The inhibitory activity of 2-phosphono-butane 1,2,4 tricarboxylic acid (PBTA) in the formation of hydroxyapatite (HA) was studied in vitro and in vivo. PBTA, at 4 ppm, inhibited the spontaneous formation of HA in vitro from a supersaturated solution. PBTA, at 2 ppm, completely inhibited the crystal growth of HA; at lower concentrations, a direct relationship was found between the reduction of the initial precipitation rates and PBTA concentrations in the solution. The effects of PBTA on human dental enamel in vitro were also evaluated at pH 5.0 and 7.5. Equimolar levels of EDTA served as the controls. In comparison with EDTA, the dissolution of enamel induced by PBTA was negligible. One percent solution of PBTA was evaluated in a rat calculus assay. In comparison with a placebo solution, it significantly (p = 0.05) reduced calculus formation when applied topically. It was also tested against calculus formation in beagle dogs. A topical application once a day of a 1% solution at pH 7.0 reduced calculus formation by 84% for 16 weeks. Analysis of these data suggests that the agent effectively reduces calculus formation in vivo.

Animals↗
PubMed1984

Studies on the formation of electrostatic complexes between benzethonium chloride and anionic polymers.

The chemistry of a mixture of benzethonium chloride and a copolymer of methoxyethylene-maleic anhydride was investigated. This mixture was of interest because it was effective in reducing dental plaque, calculus, and gingival inflammation in vivo. Evidence from dialysis, pH measurements, and stoichiometry demonstrated that the benzethonium cation and the anion of the hydrolyzed copolymer formed an electrostatic complex. An emulsion was produced when a stoichiometric excess of either component was present, but this mixture coacervated at stoichiometric quantities. The stability of the complex was pH dependent, and it did not form in 50% acetone. The complex was decomposed by simulated saliva, mainly due to calcium and magnesium ions, but was unaffected by salivary proteins. Other anionic polymers also formed this type of complex.

Acetone↗
PubMed1983

Effects of EDITEMPA on dental calculus and caries formation in vivo.

N,N,N',N'-ethylene diamine tetra (methylene phosphonic acid)--EDITEMPA--was highly effective in reducing dental calculus formation in beagle dogs when applied topically as a 1% solution or in a mouth rinse. A dose-response study in 40 beagles for 12 weeks with dentifrices containing 1, 2, 2.75, and 2.75% EDITEMPA + 0.1% NaF gave a significant (alpha = 0.05) reduction in calculus formation. Based on these results, it was also concluded that 0.1% NaF did not affect the anticalculus activity of 2.75% EDITEMPA. The effect of EDITEMPA dentifrice on dental caries in rats was also studied. A dentifrice containing 1.69% EDITEMPA significantly (alpha less than 0.01) reduced smooth and fissure caries in rats when applied topically. Collectively, the data suggested that EDITEMPA was an effective anticalculus agent and that it did not damage developing enamel in vivo.

Animals↗
PubMed1982

Colonization of the oropharynx with Gram-negative bacilli in children with severe protein-calorie malnutrition.

Oral pharyngeal isolation of Gram-negative bacteria was compared in four groups of Bengali children; acutely ill, severely malnourished outpatients swabbed on hospital admission; ill but less severely malnourished outpatients from the same area as the malnourished children; orphans also less severely malnourished but not acutely ill; and well controls drawn from a priviledged socioeconomic group. The expected weight for height percentage (National Center Health Statistics/Center for Disease Control median) of the four groups was respectively 67, 91, 97, and 97%. Isolation of Gram-negative bacteria from 74 of 87 (85%) severely malnourished children was significantly greater (p less than 0.01) compared to 43 of 113 (38%) outpatients, to 20 of 93 (22%) orphans, and to five of 51 (10%) controls. A total of 71 malnourished children under 5 yr of age (90%) had higher rates of Gram-negative throat colonization than did 16 older children (63%) (p less than 0.01). Thus there was an increased rate of Gram-negative colonization in severely malnourished children especially among the younger age group. In the subset of ill children, Gram-negative pharyngeal colonization was significantly associated inversely with nutritional indices and age. The high rate of such carriage may be partly responsible for the increased susceptibility of Gram-negative infection demonstrated in these children.

Body Height↗