Polyvinyl Methyl Ether Maleic Acid Research Articles

Effects of desensitizing dentifrices on dentin tubule occlusion and resistance to erosive challenges

BackgroundMany studies have demonstrated efficacy of casein phosphopeptide (CPP) containing products for dentin tubule occlusion for treatment of dentin sensitivity, but their effectiveness under dynamic erosive challenges remains to be elucidated. The purpose of the present study was to investigate the effectiveness of a desensitizing dentifrice containing CPP in occluding dentin tubules and resisting erosive challenges in comparison to that containing polyvinyl methyl ether/maleic acid (PVM/MA) copolymers.Methods A total of 33 dentin discs were prepared from coronal sections of human third molars and divided into 3 groups: a toothpaste containing CPP; a toothpaste containing PVM/MA and submicron silica; and a regular toothpaste (Controls). A soft-bristle toothbrush was used to brush the dentin discs with the dentifrices for 45 strokes in 30 s at a force of approximately 200 g. The brushing cycle was repeated after immersion of the dentin discs in artificial saliva overnight. The dentin discs were then challenged in orange juice for 10 min in an incubator rocking at 120 rpm. Three fields were randomly selected on each dentin disk surface to assess dentin tubule occlusions after each brushing cycle and after orange juice challenge with a 3D laser scanning microscope. Specimen cross sections were examined with a scanning electron microscope equipped with energy dispersive spectroscopy (SEM/EDS).ResultsAfter the first and second cycles of brushing, dentin tubules were occluded on average by 56.3% and 85.7% in CPP group, 66.2% and 88.1% in PVM/MA group, and 0.0 and 13.0% in the controls, respectively. There were no statistically significant differences in dentin tubule occlusions between the CPP and PVM/MA groups after two cycles of brushing (p>0.05). After dynamic erosive challenges with orange juice, 20.3% of the dentin tubules in the CPP group, 79.1% in the PVM/MA group and none in the control remained occluded (P<0.05). SEM/EDS imaging showed that dentin tubules were blocked with plugs containing dentifrice substances in CPP and PVM/MA groups after treatments, but none in the controls.ConclusionsDesensitizing dentifrices containing CPP or PVM/MA could effectively occlude dentin tubules after two cycles of brushing. PVM/MA in combination with submicron silicon dioxide exhibited stronger resistance to dynamic erosive challenges by acidic beverages. Inorganic fillers that can enter dentin tubules and resist erosive challenges may be key for desensitizing dentifrices.

Dentin tubule occlusion and erosion protection effects of dentifrice containing bioadhesive PVM/MA copolymers

To study the effectiveness of a dentifrice containing polyvinylmethyl ether-maleic acid (PVM/MA) copolymer in occluding dentin tubules and investigate the interaction between PVM/MA and type I collagen using surface plasmon resonance (SPR). Fifteen volunteers brushed dentin discs in situ using dentifrices with and without PVM/MA copolymer in a cross-over design. Dentin tubule occlusion was evaluated after brushing, after overnight saliva challenge in vivo for 12 h and after drinking 250 ml of orange juice. Dentin tubule occlusion and tubule size were compared between the two groups using repeated ANOVA and before and after erosive challenges using paired t tests. SPR using type I collagen as ligand and PVM/MA as analyte was performed to evaluate the binding of the two macromolecules. A median of 91% of dentin tubules were occluded after a single brushing in the PVM/MA group, as compared to 9% in the controls. After overnight saliva challenge and 10 min of erosion by orange juice, a median of 73% of the dentin tubules remained fully occluded in the PVM/MA group as compared to zero in the controls. Dentin tubule size increased after orange juice erosion in the controls but not in the PVM/MA group. SPR study showed that PVM/MA bound readily to collagen molecules in a 4 to 1 ratio. Dentifrice containing PVM/MA could effectively occlude dentin tubules and prevent dentin erosion. PVM/MA may improve adhesive retention of intra-tubular dentifrice plugs through binding to dentin surface collagen. Brushing with dentifrice containing adhesive polymers has preventive effect against dentin erosion and dentin sensitivity.

Final Report of the Amended Safety Assessment of PVM/MA Copolymer and Its Related Salts and Esters as Used in Cosmetics

Polyvinyl methyl ether/maleic acid (PVM/MA) copolymer, and its related salts and esters, are used in cosmetics, mainly as binders, film formers, and hair fixatives. Animal and human data relevant to the use of these ingredients in cosmetic products were reviewed by the CIR Expert Panel. The Panel concluded that these ingredients are safe for use in cosmetic products.

Effectiveness of Three Different Toothpaste Formulations in Reduction of Plaque and Gingivitis: A Comparative Clinical Study

ABSTRACT The role of dental plaque in gingivitis and periodontitis is well established. It is commonly observed that daily brushing often fails to achieve and maintain optimum gingival health. In order to improve the efficacy of the self-performed mechanical tooth cleaning procedure, antimicrobial substances like chlorhexidine, metallic ions, fluorides and various phenolic compounds have been evaluated, as such adjuvants in clinical trials that have been added to dentifrice used during tooth brushing. Triclosan (2, 4, 4' trichloro-2'hydroxyphenylether) is a nonionic antibacterial agent with broad spectrum activity against both gram-positive and gram-negative organisms. Recently, triclosan was introduced in toothpaste and mouth rinses for control of plaque and gingivitis. However, maximum antiplaque activity is shown when triclosan is used in combination with agents like copolymer polyvinyl methyl ether maleic acid (PVM/MA). The PVM/MA copolymer retains the triclosan on the soft and hard surfaces of the oral cavity for several hours. This study aims in proving efficacy of triclosan copolymer toothpaste over the triclosan alone and non-triclosan toothpaste in reduction of plaque and gingivitis.

Effect of triclosan/copolymer‐containing toothpaste on the association between plaque and gingival bleeding: a randomized controlled clinical trial

To study longitudinal associations between plaque and gingival bleeding and multilevel variance/covariance structures after introducing triclosan-containing toothpaste. A 10-week, randomized, two-arm, double-masked, controlled clinical trial was conducted in 34 healthy, non-smoking females with plaque-induced gingivitis. Clinical periodontal examinations were repeated every other week. At week 4, test toothpaste containing 0.24% sodium monofluorophosphate, 0.3% triclosan, and 2% polyvinyl-methyl ether maleic acid; or control toothpaste containing 0.76% sodium monofluorophosphate and 0.1% sodium fluoride, were randomly distributed. Multivariate multilevel models indicated that, after introducing experimental toothpastes, subject random error was reduced from 0.6 to below 0.2. The odds ratio (OR) of bleeding on probing (BOP) was about 30% less in the test than in the control group (p<0.01). At the end of the experiment, ORs for BOP and plaque index scores 1-3 (reference 0) were 2.1-2.4 in the control group, but 1.1-1.9 in the test group (p<0.05). No effects on plaque levels and calculus were observed. Multivariate multilevel modelling allows the study of fixed and random effects of experimental toothpastes on gingival inflammation in small sample. Triclosan appears to attenuate the causal association between supragingival plaque and gingival bleeding in gingivitis.

The effect of a polyhexamethylene biguanide mouthrinse compared with a triclosan rinse and a chlorhexidine rinse on bacterial counts and 4‐day plaque re‐growth

For various clinical applications, polyhexamethylene biguanide hydrochloride (PHMB) has been used for many years as an antiseptic in medicine. Recently, a 0.04% and a 0.12% PHMB mouthwash were shown to inhibit plaque re-growth and to reduce oral bacterial counts. In this study, a 0.2% PHMB mouthrinse (A) was compared with a positive control 0.12% aqueous chlorhexidine solution (B), a commercially available 0.3% triclosan/2.0% polyvinyl methyl ether maleic acid copolymer mouthrinse (Colgate Total Plax) (C), and a negative control placebo rinse (10% ethanol, flavour) (D). The controlled clinical study was a double blind, randomized, four replicate cross - over design. Plaque re-growth was assessed with the Turesky et al. (1970) modification of the Quigley & Hein (1962) plaque index. The antibacterial effect was assessed by taking bacterial counts on the tooth surface (smears from the buccal surface of 16/26) and mucosa (smears from the buccal mucosa in opposite of area 16/26) after the professional prophylaxis and after the first rinse with the preparations on day 1 and prior to the clinical examination on day 5. Sixteen volunteers participated and, on day 1 of each study period were rendered plaque-free, ceased toothcleaning, and rinsed twice daily with the allocated mouthrinse. On day 5, plaque was scored and smears were collected according to the protocol. A 10-day wash-out period was carried out between each rinse evaluation. Data were analysed using ancova with Bonferroni HSD adjustment for multiple comparisons (colony forming units per sample) with a significance level alpha=0.05. The 0.2% PHMB mouthrinse (A) was significantly better at inhibiting plaque than the placebo (D), but significant less effective than the 0.12% aqueous chlorhexidine solution (B). There is no significant difference between A and the 0.3% triclosan/2.0% copolymer mouthrinse (C). Bacterial count reductions (tooth surface and mucosa) with PHMB (A) were significantly greater compared with the placebo (D) and triclosan (C), but significantly lower compared with chlorhexidine (B) (tooth surface) and equally effective compared with chlorhexidine (B) (mucosa). Consistent with previous studies, a PHMB mouthrinse was shown to inhibit plaque re-growth and to reduce oral bacterial counts, indicating that PHMB could be an alternative to established mouthrinses in preventive applications.

O10 The technology behind Colgate® TotalTM toothpaste

In the early 1990s, a break‐through toothpaste, known as Colgate® Total™, was launched with documented long‐lasting activity against plaque, gingivitis, calculus, tooth decay and bad breath. The technology behind this toothpaste is the combination of triclosan, a polyvinyl methyl ether maleic acid (PVM/MA) copolymer and sodium fluoride (TCF). The function of the copolymer is to ensure optimal oral retention and prolonged release of the antibacterial triclosan. Effective levels of triclosan have been measured in the oral cavity 12 h after brushing the teeth. This allows prolonged control of oral bacteria that can lead to the formation of dental plaque and gingivitis and bad breath. Similarly, the retention of triclosan to oral surfaces during 2 years regular use of the product has led to a significant reduction in incremental coronal caries compared to an ADA‐approved anti‐cavity fluoride toothpaste. Furthermore, significantly less calcium phosphate has been shown to be present in dental plaque after brushing the teeth with the triclosan/copolymer toothpaste, and this has resulted in the reduced formation of tartar. A new variant of the triclosan/copolymer/fluoride toothpaste, having the numerous therapeutic and aesthetic benefits of the original formula, has been made available to consumers. The new dentifrice, which contains an impactful breath freshening flavor, has been documented to be significantly better (P &lt; 0.05) than a control toothpaste in providing sustained control of bad breath over 12 h. After 12 h, breath odor was reduced from 51% compared to the control. The long term retention and subsequent release of triclosan by the copolymer in the TCF formula provide consumers protection against plaque, gingivitis, tartar, caries and bad breath.

Clinical effectiveness of a triclosan/copolymer/sodium fluoride dentifrice in controlling oral malodor: a 3‐week clinical trial

Objective: The purpose of the study was to compare the effectiveness of a dentifrice containing 0.3% triclosan, 2% polyvinylmethylether/maleic acid (PVM/MA) copolymer, 0.243% sodium fluoride (TCF) to a commercially‐available dentifrice containing 0.243% sodium fluoride (control) for the management of oral malodor in a 3‐week, randomized double‐blind, longitudinal clinical trial.Methods: A panel of four expert judges used a nine‐point hedonic scale to evaluate breath odor using a protocol designed in accordance with the ADA Draft Acceptance Program Guideline for Products Used in the Management of Oral Malodor. Following a baseline evaluation, prospective subjects with hedonic scores above the threshold value for unpleasant breath were stratified by score and randomized into two treatment groups. Subjects brushed their teeth for 1 min with their assigned dentifrice after which they were scored for oral malodor at 1.5, 4 and 12 h. They then used their assigned dentifrice, twice a day, for 3 weeks. Before oral malodor evaluations, the subjects refrained from eating odorigenic foods, using mouthrinses and breath mints and from performing dental hygiene procedures.Results: Eighty‐one adult male and female subjects completed the study. The baseline hedonic scores for the TCF and control dentifrices were 7.80 and 7.84, respectively, corresponding to unpleasant breath. The final mean oral malodor scores for the TCF dentifrice differed significantly from the baseline and control values (P &lt; 0.05) for every time point examined (1.5‐, 4‐, 12‐h and 1‐, 2‐ and 3‐week intervals). The mean final breath scores for the TCF dentifrice group were 3.06, 3.48, 3.42, 3.66, 3.41 and 3.36, respectively, for each time point. These scores correspond to pleasant breath. Conversely, the control dentifrice group scored at levels either above 5.0 (before 12 h) or above 7.0 (after 12 h) which corresponded to neutral or unpleasant breath.Conclusion: In conclusion, the results of this double‐blind clinical study clearly indicate that a dentifrice containing triclosan/copolymer/NaF provides effective control of oral malodor for up to 12 h.

P18 Clinical effectiveness of a triclosan/copolymer/ sodium fluoride dentifrice in controlling oral malodor: a three‐week clinical trial

Objective The purpose of the study was to compare the effectiveness of a dentifrice containing 0.3% triclosan/2% polyvinylmethylether/maleic acid (PVM/MA) copolymer/0.243% sodium fluoride (TCF) to a commercially‐available dentifrice containing 0.243% sodium fluoride (control) for the management of oral malodor in a 3‐week, randomized double‐blind, longitudinal clinical trial.Methods A panel of four expert judges used a nine‐point hedonic scale to evaluate breath odor using a protocol designed in accordance with the ADA Draft Acceptance Program Guideline for Products Used in the Management of Oral Malodor. Following a baseline evaluation, prospective subjects with hedonic scores above the threshold value for unpleasant breath were stratified by score and randomized into two treatment groups. Subjects brushed their teeth for 1 min with their assigned dentifrice, twice a day, for 3 weeks. Before oral malodor evaluations, the subjects refrained from eating odorigenic foods, from using mouthrinses and breath mints and from performing dental hygiene procedures.Results Eighty‐one adult male and female subjects completed the study. The baseline hedonic scores for the TCF and control dentifrices were 7.80 and 7.84, respectively, corresponding to unpleasant breath. The final mean oral malodor scores for the TCF dentifrice differed significantly from the baseline and control values (P &lt; 0.05) for every time point examined (1.5‐, 4.0‐, 12.0‐h and 1‐, 2‐ and 3‐week intervals). The mean final breath scores for the TCF dentifrice group were 3.06, 3.48, 3.42, 3.66, 3.42 and 3.36, respectively, for each time point. These scores correspond to pleasant breath. Conversely, the control dentifrice group scored at levels either above 5.0 (before 12 h) or above 7.0 (after 12 h) which corresponded to neutral or unpleasant breath.Conclusion In conclusion, the results of this double‐blind clinical study clearly indicate that a dentifrice containing triclosan/copolymer/NaF provides effective control of oral malodor for up to 12 h.

Interaction of triclosan with eukaryotic membrane lipids.

The possibility that triclosan and PVM/MA (polyvinylmethyl ether/maleic acid) copolymer, additives to dentrifrices, could interact with eukaryotic membrane lipids was studied by two methods: first, by determining the pressure/molecular area isotherms at 37 degrees C of glycerophospholipid monolayers, using the Langmuir technique; and second, by phase-transition parameters in liposomes of the same lipids, using differential scanning calorimetry (DSC). Triclosan interacted, in a concentration-independent manner, with monolayers of saturated phosphatidylcholines (PC; i.e. markers of the outer membrane leaflet of eukaryotic cells). Triclosan and PVM/MA copolymer mixtures were shown to clearly interact in a concentration-dependent manner with PC. Triclosan was found to interact with liposomes of saturated and unsaturated phosphatidylcholines and phosphatidylserines (PS; i.e. markers of the inner membrane leaflet of eukaryotic cells), and saturated ethanolamines (PE; i.e. markers of the inner membrane leaflet of eukaryotic cells), resulting in a decrease of the lipid melting temperature (Tm). PVM/MA copolymer changed the Tm of PS, PC, and PE in different manners. By adding PVM/MA or triclosan-PVM/MA copolymer mixtures to 1-stearoyl-2-oleoyl-sn-glycero-3-phosphoserine (SOPS) no lipid transitions were detected. A biphasic change of the PC transition temperature resulted when triclosan or triclosan PVM/MA copolymer mixtures were added, indicating domain formation and change of the lipid polymorphism.