The effectiveness of using dye models for small tissue biopsies in the surgical pathology laboratory.

INTRODUCTION: Losing of small tissues during tissue preparatory steps may seriously affect pathological diagnostic performance. Using an appropriate tissue marking dye could be an alternative solution. Therefore, the aim of the study was to find a suitable tissue marking dye to enhance the observable ability of various types of small-size tissues during several steps of tissue preparation. MATERIAL AND METHODS: Various small-size samples of various organs and tissues (0.2 to 0.3 cm), including breast, endometrial, and cervical tissue, stomach, small and large intestine, lung, and kidney, were marked with different dyes such as merbromin, hematoxylin, eosin, crystal violet, and alcian blue prior to tissue processing step and their colored-observable ability was evaluated by pathology assistants. Moreover, the diagnostic interfering effect of each tissue marking dye was determined by pathologists. RESULTS: Merbromin, hematoxylin, and alcian blue increased the colored-observable ability of small tissue samples. We suggest using hematoxylin as a tissue marking dye over merbromin and alcian blue because of less toxicity and no interference effect in the step of routine pathological slide examination. CONCLUSIONS: Hematoxylin could be a suitable tissue marking dye for small-size samples and may improve the preanalytical process of tissue preparation in pathological laboratories.

Comparative Study between Acacia Nilotica versus Povidone Iodine in Topical Treatment of Omphalocele Major.

Well established and common practice in conservative management of omphalocele major is escharotics therapy with different topical agents. Among them mercurochrome, alcohol, silver salts, povidone iodine, acacia nilotca paste are commonly used. It is a comparative study between application of acacia nilotica paste and povidone iodine solution as a primary non surgical treatment of omphalocele major regarding efficacy and safety of these two topical agents. A double blind randomized controlled study was conducted at the department of Paediatric Surgery, Mymensingh Medical College Hospital, Mymensingh, Bangladesh from July 2016 to June 2019. In this study 20 cases of omphalocele major and randomly divided into two equal groups. Group A and Group B treated with acacia nilotica paste and povidone iodine solution respectively. Gastroschisis, ruptured-omphalocele major or omphalocele minor excluded in this study. The size of the fascial defect in cm, time required for full oral feeding tolerance and duration of hospital stay were evaluating parameters. Patients with Group A tolerated full oral feeding earlier, shorter total hospital stay duration and low mortality rate than those from Group B. Application of acacia nilotica is a safe and effective treatment of omphalocele major regarding rapid full oral feeding tolerance, shorter hospital stay and low mortality rate.

Approved spectrofluorimetric strategies for assurance of three modern antineoplastic drugs: tepotinib, sotorasib, and darolutamide in their dose forms and biological liquids utilizing mercurochrome.

An approved, straightforward, fast, and delicate spectrofluorimetric strategy was developed for the estimation of tepotinib (TEPO), sotorasib (SOTO), and darolutamide (DARO) as new antineoplastic drugs. The spectrofluorimetric strategy was based on quantitative fluorescence quenching of MER at 538 nm after being excited at 350 nm by the addition of the cited drugs in the presence of acetate buffer (pH 3.5). The degree of fluorescence quenching was directly proportional to the concentrations of the cited drugs within the concentration range of 0.5-10.0, 0.2-10, and 0.4-10.0 µg ml-1 for TEPO, SOTO, and DARO, respectively. Mean ± standard deviation (SD) were calculated for the studied drugs as follows; 99.9 ± 0.87, 99.72 ± 1.08, and 100.21 ± 1.44, for TEPO, SOTO, and DARO, respectively. Limit of detection (LOD) values were 0.16, 0.05, and 0.11 µg ml-1 , whereas limit of quantitation (LOQ) values were 0.5, 0.15, and 0.36 µg ml-1 for TEPO, SOTO, and DARO, respectively. Statistical comparison through detailed strategies produced greater understanding and found that there were no noteworthy contrasts in exactness and exactness between strategies. The proposed strategy was used effectively to analyze the measurement of different forms of the examined drugs. Moreover, the recommended fluorimetric strategy was used for examination of TEPO, SOTO, and DARO in human plasma and urine tests.

Merbromin is a mixed-type inhibitor of 3-chyomotrypsin like protease of SARS-CoV-2.

3-chyomotrypsin like protease (3CLpro) has been considered as a promising target for developing anti-SARS-CoV-2 drugs. Herein, about 6000 compounds were analyzed by high-throughput screening using enzyme activity model, and Merbromin, an antibacterial agent, was identified as a potent inhibitor of 3CLpro. Merbromin strongly inhibited the proteolytic activity of 3CLpro but not the other three proteases Proteinase K, Trypsin and Papain. Michaelis-Menten kinetic analysis showed that Merbromin was a mixed-type inhibitor of 3CLpro, due to its ability of increasing the KM and decreasing the Kcat of 3CLpro. The binding assays and molecular docking suggested that 3CLpro possessed two binding sites for Merbromin. Consistently, Merbromin showed a weak binding to the other three proteases. Together, these findings demonstrated that Merbromin is a selective inhibitor of 3CLpro and provided a scaffold to design effective inhibitors of SARS-CoV-2.

Applying different spectroscopic techniques for the selective determination of daclatasvir using merbromin as a probe: Applications on pharmaceutical analysis.

In this study, rapid resonance Rayleigh scattering (RRS), spectrophotometric, and spectrofluorimetric methods were performed for facile quantitation of daclatasvir dihydrochloride without interference from sofosbuvir (a co-formulated anti-hepatitis C virus drug). The proposed approaches were based on forming a binary complex between daclatasvir dihydrochloride and merbromin reagent at pH 4.1. The binary complex was measured spectrophotometrically at λmax = 544 nm. The spectrofluorimetric approach relied on the quenching effect of daclatasvir dihydrochloride on the fluorescence strength of merbromin at λEmission = 545 nm. The RRS approach depended on augmentation in the merbromin RRS spectrum at 363 nm upon addition of daclatasvir dihydrochloride. The presented methodologies were linear over the concentration ranges 2.5-15.0, 0.2-1.6 and 0.15-3.0 µg ml-1 with detection limits of 0.45, 0.046, and 0.036 µg ml-1 for the spectrophotometric approach, the spectrofluorometric approach, and RRS approach, respectively. Current approaches were validated in compliance with International Council for Harmonisation guidelines and utilized practically to estimate daclatasvir dihydrochloride either in binary mixtures with sofosbuvir or in its commercial tablet dosage form with good results. Moreover, the test for content uniformity was applied successfully on commercial tablets using the current spectroscopic approaches.

Exploring the Human Cytomegalovirus Core Nuclear Egress Complex as a Novel Antiviral Target: A New Type of Small Molecule Inhibitors.

Nuclear egress is an essential process in the replication of human cytomegalovirus (HCMV), as it enables the migration of newly formed viral capsids from the nucleus into the cytoplasm. Inhibition of the HCMV core nuclear egress complex (core NEC), composed of viral proteins pUL50 and pUL53, has been proposed as a potential new target for the treatment of HCMV infection and disease. Here, we present a new type of small molecule inhibitors of HCMV core NEC formation, which inhibit the pUL50-pUL53 interaction at nanomolar concentrations. These inhibitors, i.e., verteporfin and merbromin, were identified through the screening of the Prestwick Chemical Library® of approved drug compounds. The inhibitory effect of merbromin is both compound- and target-specific, as no inhibition was seen for other mercury-organic compounds. Furthermore, merbromin does not inhibit an unrelated protein-protein interaction either. More importantly, merbromin was found to inhibit HCMV infection of cells in three different assays, as well as to disrupt HCMV NEC nuclear rim formation. Thus, while not being an ideal drug candidate by itself, merbromin may serve as a blueprint for small molecules with high HCMV core NEC inhibitory potential, as candidates for novel anti-herpesviral drugs.

New spectroscopic methods for determination of dexlansoprazole using mercurochrome.

New spectroscopic methods were developed for dexlansoprazole estimation in capsule formulation based on the formation of a reaction between dexlansoprazole and Mercurochrome (MER) at pH 3.7. The formed complex was measured spectrophotometrically (Method I) at 557 nm and spectrofluorometrically (Method II) at 300 nm/538 nm, because the drug caused quantitative quenching of the native fluorescence of Mercurochrome. The spectrophotometric method was linear over the concentration 25-55 µg/ml with a limit of detection (LOD) of 1.15 µg/ml and a limit of quantification (LOQ) of 3.48 µg/ml. The spectrofluorometric method had a linear range 20-45 µg/ml with an LOD of 1.13 µg/ml and an LOQ of 3.45 µg/ml. The suggested methods were used to analyze capsules to test the interference from excipients and the data indicated good selectivity. Data obtained were statistically analyzed and were favourably good. The new methods are environmentally benign and depend on distilled water mainly as the diluting solvent. This property was confirmed by assessing their greenness.

The leading established metal-based drugs: a revisitation of their relevant physico-chemical data.

The study of metal-based drugs represents an important branch of modern bioinorganic chemistry. The growing importance of this field is linked to the large success in medicine of a few metal based drugs, either in clinical use or still experimental. Moreover, these metal-based drugs are frequently used as reference compounds to assess comparatively the behavior of newly synthesized metallodrugs. For the convenience of researchers working in this area we report here a compilation of the relevant analytical and spectroscopic data of ten representative metallodrugs based on Platinum, Ruthenium, Gold and Mercury. The selected compounds, namely Cisplatin, Oxaliplatin, Carboplatin, Auranofin, Sodium Aurothiomalate, NAMI-A, KP1019, Thimerosal, Merbromin and Phenylmercury Acetate, were chosen owing to their importance in the field. We believe that this compilation may turn very helpful to researchers as these data are difficult to find and generally scattered over a large number of (old) publications.

Auditory and Histopathological Effects of Topical Mercurochrome Treatment in Rats with Tympanic Membrane Perforation.

OBJECTIVES: Topical treatment is first choice in the treatment of uncomplicated chronic otitis media. It was intended to assess auditory and histopathological safety of ototopical use of mercurochrome solution in rats with induced tympanic membrane perforation. MATERIALS AND METHODS: The study was conducted on 21 female Wistar-Albino rats which were randomly assigned into 3 groups. In all rats, perforation was performed at right tympanic membrane. Distortion product otoacoustic emissions (DPOAEs) measurements were performed at frequencies of 2000, 3000 and 4000 Hz (with L1/L2: 70 /70 dB at 2f1-f2 frequency; f2/f1 ratio: 1:22) before recovery from anesthesia and signal-to-noise ratio (SNR) were recorded. Normal saline, 2% mercurochrome and gentamicin were given to group 1, 2 and 3 twice daily over a week, respectively. Rats were sacrificed after DPOAE measurements on day 14. Right temporal bone specimens were examined under light microscope after processing. RESULTS: Based on DPOAE results, there was no significant difference among groups before treatment. On day 14, significant differences were found in DPOAE measurements at 3000 and 4000 Hz, and in mean SNR values in 2% mercurochrome and gentamicin groups when compared to normal saline group while no significant difference was detected at 2000 Hz among groups. In addition, significant degeneration was detected in Corti organs, spiral ganglions and stria vascularis in groups 2 and 3. CONCLUSION: In this study, it was observed that mercurochrome use in external otitis and otitis media with tympanic membrane perforation could cause ototoxicity and concluded that the solution should be used cautiously.

Validated spectrophotometric and spectrofluorimetric methods for determination of dapoxetine hydrochloride and dosulepin hydrochloride in their dosage forms using mercurochrome.

Validated, simple, rapid and sensitive spectrophotometric and spectrofluorimetric methods were developed for the determination of dapoxetine HCl and dosulepin HCl. The spectrophotometric method (I) was based on a binary complex formation between each drug and mercurochrome (MER) in acetate buffer (pH 3.5) with maximum absorbance at 557 nm. Calibration graphs were linear over the range 2.0-20.0 and 2.0-24.0 µg/ml, detection limits were 0.23 and 0.41 µg/ml and quantitation limits were 0.71 and 1.26 µg/ml for dapoxetine HCl and dosulepin HCl, respectively. Spectrofluorimetric method (II) was based on the measurement of the quantitative quenching effect of each drug on the native fluorescence of MER at the same pH. Fluorescence quenching of MER was measured at 538 nm after excitation at 470 nm. Calibration graphs were linear over the range 0.5-10.0 and 0.4-10.0 µg/ml, detection limits were 0.17 and 0.12 µg/ml and quantitation limits were 0.5 and 0.36 µg/ml for dapoxetine HCl and dosulepin HCl, respectively. Statistical comparison of results with those obtained by reported methods provided good agreement and revealed that there were no significant differences in accuracy and precision between methods. The proposed methods were applied successfully to analyse commercial tablets and capsules containing the studied drugs.

Prospective Single-Center Observational Study of the Allergenic Potential of Mercromina Film and Other Common Antiseptics in Patients With Contact Dermatitis. / Estudio observacional de seguridad, prospectivo y unicéntrico para determinar la capacidad alergogénica de Mercromina Film® y otros antisépticos de uso común en pacientes con dermatitis de contacto.

INTRODUCTION: Although Mercromina Film and other topical antiseptics are widely used, they are not included in the standard series recommended by the Spanish Contact Dermatitis and Skin Allergy Research Group for testing suspected allergic contact dermatitis (ACD). Furthermore, no recent studies have investigated the allergenic potential of merbromin. OBJECTIVE: To determine the allergenic potential of merbromin and compare it with that of other topical antiseptics widely used in clinical practice, including povidone-iodine, chlorhexidine, and eosin. MATERIAL AND METHODS: Prospective single-center observational safety study of 105 patients with suspected ACD seen at the dermatology department of our hospital. RESULTS: Of the 105 patients studied, 1.9% had a positive patch test to merbromin and 12.4% were sensitized to povidone-iodine. The differences in the proportion of patients with ACD to Betadine Solución Dérmica (povidone-iodine) compared with the rest of the antiseptics was statistically significant (McNemar test, P<.05). No adverse reactions were observed in any of the patients. CONCLUSIONS: Based on the patch tests conducted, Mercromina Film has very low allergenic potential. The highest allergenic potential was observed for povidone-iodine.

Antiseptics for burns.

BACKGROUND: Burn wounds cause high levels of morbidity and mortality worldwide. People with burns are particularly vulnerable to infections; over 75% of all burn deaths (after initial resuscitation) result from infection. Antiseptics are topical agents that act to prevent growth of micro-organisms. A wide range are used with the intention of preventing infection and promoting healing of burn wounds. OBJECTIVES: To assess the effects and safety of antiseptics for the treatment of burns in any care setting. SEARCH METHODS: In September 2016 we searched the Cochrane Wounds Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), Ovid MEDLINE, Ovid MEDLINE (In-Process & Other Non-Indexed Citations), Ovid Embase, and EBSCO CINAHL. We also searched three clinical trials registries and references of included studies and relevant systematic reviews. There were no restrictions based on language, date of publication or study setting. SELECTION CRITERIA: We included randomised controlled trials (RCTs) that enrolled people with any burn wound and assessed the use of a topical treatment with antiseptic properties. DATA COLLECTION AND ANALYSIS: Two review authors independently performed study selection, risk of bias assessment and data extraction. MAIN RESULTS: We included 56 RCTs with 5807 randomised participants. Almost all trials had poorly reported methodology, meaning that it is unclear whether they were at high risk of bias. In many cases the primary review outcomes, wound healing and infection, were not reported, or were reported incompletely.Most trials enrolled people with recent burns, described as second-degree and less than 40% of total body surface area; most participants were adults. Antiseptic agents assessed were: silver-based, honey, Aloe Vera, iodine-based, chlorhexidine or polyhexanide (biguanides), sodium hypochlorite, merbromin, ethacridine lactate, cerium nitrate and Arnebia euchroma. Most studies compared antiseptic with a topical antibiotic, primarily silver sulfadiazine (SSD); others compared antiseptic with a non-antibacterial treatment or another antiseptic. Most evidence was assessed as low or very low certainty, often because of imprecision resulting from few participants, low event rates, or both, often in single studies. Antiseptics versus topical antibioticsCompared with the topical antibiotic, SSD, there is low certainty evidence that, on average, there is no clear difference in the hazard of healing (chance of healing over time), between silver-based antiseptics and SSD (HR 1.25, 95% CI 0.94 to 1.67; I2 = 0%; 3 studies; 259 participants); silver-based antiseptics may, on average, increase the number of healing events over 21 or 28 days' follow-up (RR 1.17 95% CI 1.00 to 1.37; I2 = 45%; 5 studies; 408 participants) and may, on average, reduce mean time to healing (difference in means -3.33 days; 95% CI -4.96 to -1.70; I2 = 87%; 10 studies; 979 participants).There is moderate certainty evidence that, on average, burns treated with honey are probably more likely to heal over time compared with topical antibiotics (HR 2.45, 95% CI 1.71 to 3.52; I2 = 66%; 5 studies; 140 participants).There is low certainty evidence from single trials that sodium hypochlorite may, on average, slightly reduce mean time to healing compared with SSD (difference in means -2.10 days, 95% CI -3.87 to -0.33, 10 participants (20 burns)) as may merbromin compared with zinc sulfadiazine (difference in means -3.48 days, 95% CI -6.85 to -0.11, 50 relevant participants). Other comparisons with low or very low certainty evidence did not find clear differences between groups.Most comparisons did not report data on infection. Based on the available data we cannot be certain if antiseptic treatments increase or reduce the risk of infection compared with topical antibiotics (very low certainty evidence). Antiseptics versus alternative antisepticsThere may be some reduction in mean time to healing for wounds treated with povidone iodine compared with chlorhexidine (MD -2.21 days, 95% CI 0.34 to 4.08). Other evidence showed no clear differences and is of low or very low certainty. Antiseptics versus non-antibacterial comparatorsWe found high certainty evidence that treating burns with honey, on average, reduced mean times to healing in comparison with non-antibacterial treatments (difference in means -5.3 days, 95% CI -6.30 to -4.34; I2 = 71%; 4 studies; 1156 participants) but this comparison included some unconventional treatments such as amniotic membrane and potato peel. There is moderate certainty evidence that honey probably also increases the likelihood of wounds healing over time compared to unconventional anti-bacterial treatments (HR 2.86, 95% C 1.60 to 5.11; I2 = 50%; 2 studies; 154 participants).There is moderate certainty evidence that, on average, burns treated with nanocrystalline silver dressings probably have a slightly shorter mean time to healing than those treated with Vaseline gauze (difference in means -3.49 days, 95% CI -4.46 to -2.52; I2 = 0%; 2 studies, 204 participants), but low certainty evidence that there may be little or no difference in numbers of healing events at 14 days between burns treated with silver xenograft or paraffin gauze (RR 1.13, 95% CI 0.59 to 2.16 1 study; 32 participants). Other comparisons represented low or very low certainty evidence.It is uncertain whether infection rates in burns treated with either silver-based antiseptics or honey differ compared with non-antimicrobial treatments (very low certainty evidence). There is probably no difference in infection rates between an iodine-based treatment compared with moist exposed burn ointment (moderate certainty evidence). It is also uncertain whether infection rates differ for SSD plus cerium nitrate, compared with SSD alone (low certainty evidence).Mortality was low where reported. Most comparisons provided low certainty evidence that there may be little or no difference between many treatments. There may be fewer deaths in groups treated with cerium nitrate plus SSD compared with SSD alone (RR 0.22, 95% CI 0.05 to 0.99; I2 = 0%, 2 studies, 214 participants) (low certainty evidence). AUTHORS' CONCLUSIONS: It was often uncertain whether antiseptics were associated with any difference in healing, infections, or other outcomes. Where there is moderate or high certainty evidence, decision makers need to consider the applicability of the evidence from the comparison to their patients. Reporting was poor, to the extent that we are not confident that most trials are free from risk of bias.

Special Treatment and Wound Care of the Driveline Exit Site after Left Ventricular Assist Device Implantation.

OBJECTIVE: Despite good results following implantation of left ventricular assist devices (LVADs), infections of the driveline and device pocket remain a major problem for patients on long-term support. We present the data from heart failure patients treated with a Thoratec HeartMate-II LVAD (Thoratec Corporation, Pleasanton, California, United States). METHODS: From January 2008 to April 2011, in our institution, 40 heart failure patients (NYHA IV) were supported with a HeartMate-II LVAD. The driveline maintenance of 17 patients consisted of the use of Octenidine for the wound dressing, whereas merbromin was additionally used for local irrigation in 31 patients. The data concerning driveline infections were analyzed retrospectively. RESULTS: In our study, 95% of the entire cohort was free from infections of the system. Two patients in the conventional group (11.8%) developed a driveline infection at a mean of 130.5 days during 3,416 patient-days (0.21 infection/patient-years). In the Merbromid group (Co. New FaDem SRL Farmaceutici & Chimici, Giugliano, Campania, Italy), all patients were free from any driveline infections during the observation period. In a log-rank comparison, the difference reached statistical significance (p = 0.043). CONCLUSION: During our observation period, fewer infections were noted with merbromin treatment. A multicenter setting in a larger cohort should be performed to confirm these findings, although a (double-) blinded setting might be difficult to achieve.

Small molecule screening in context: lipid-catalyzed amyloid formation.

Islet Amyloid Polypeptide (IAPP) is a 37-residue hormone cosecreted with insulin by the ß-cells of the pancreas. Amyloid fiber aggregation of IAPP has been correlated with the dysfunction and death of these cells in type II diabetics. The likely mechanisms by which IAPP gains toxic function include energy independent cell membrane penetration and induction of membrane depolarization. These processes have been correlated with solution biophysical observations of lipid bilayer catalyzed acceleration of amyloid formation. Although the relationship between amyloid formation and toxicity is poorly understood, the fact that conditions promoting one also favor the other suggests related membrane active structural states. Here, a novel high throughput screening protocol is described that capitalizes on this correlation to identify compounds that target membrane active species. Applied to a small library of 960 known bioactive compounds, we are able to report identification of 37 compounds of which 36 were not previously reported as active toward IAPP fiber formation. Several compounds tested in secondary cell viability assays also demonstrate cytoprotective effects. It is a general observation that peptide induced toxicity in several amyloid diseases (such as Alzhiemer's and Parkinson's) involves a membrane bound, preamyloid oligomeric species. Our data here suggest that a screening protocol based on lipid-catalyzed assembly will find mechanistically informative small molecule hits in this subclass of amyloid diseases.

FDA-approved drugs and other compounds tested as inhibitors of human glutathione transferase P1-1.

OBJECTIVE: Glutathione transferase P1-1 (GST P1-1) is often overexpressed in tumor cells and is regarded as a contributor to their drug resistance. Inhibitors of GST P1-1 are expected to counteract drug resistance and may therefore serve as adjuvants in the chemotherapy of cancer by increasing the efficacy of cytostatic drugs. Finding useful inhibitors among compounds used for other indications would be a shortcut to clinical applications and a search for GST P1-1 inhibitors among approved drugs and other compounds was therefore conducted. METHODS: We tested 1040 FDA-approved compounds as inhibitors of the catalytic activity of purified human GST P1-1 in vitro. RESULTS: We identified chlorophyllide, merbromine, hexachlorophene, and ethacrynic acid as the most effective GST P1-1 inhibitors with IC50 values in the low micromolar range. For comparison, these compounds were even more potent in the inhibition of human GST A3-3, an enzyme implicated in steroid hormone biosynthesis. In distinction from the other inhibitors, which showed conventional inhibition patterns, the competitive inhibitor ethacrynic acid elicited strong kinetic cooperativity in the glutathione saturation of GST P1-1. Apparently, ethacrynic acid serves as an allosteric inhibitor of the enzyme. CONCLUSION AND PRACTICAL IMPLICATIONS: In their own right, the compounds investigated are less potent than desired for adjuvants in cancer chemotherapy, but the structures of the most potent inhibitors could serve as leads for the synthesis of more efficient adjuvants.

Effect of three different motivational techniques on oral hygiene and gingival health of patients undergoing multibracketed orthodontics.

OBJECTIVE: To compare the effectiveness of three different motivational techniques for maintaining good oral hygiene during fixed appliance orthodontic treatment. MATERIALS AND METHODS: A total of 62 adolescents in the age range of 12-18 years, requiring fixed orthodontic treatment were evaluated for the efficacy of three different motivational techniques, ie, conventional plaque control measures (group I), chair side motivational tests with conventional plaque control measures (group II), and phase contrast microscopy with conventional plaque control measures (group III), in improving oral hygiene and gingival health over a period of 6 months. RESULTS: A gradual decline in mean plaque scores in group III was found, ie, from 1.13 ± 0.42 at baseline to 0.64 ± 0.39 at 6 months (P < .05). An intragroup analysis of mean gingivitis scores in group III showed statistically significant decline in the mean gingival scores from 1.49 ± 0.45 to 1.08 ± 0.61 over a period of 6 months(P < .05). CONCLUSIONS: Phase contrast microscopy along with the conventional method of plaque disclosure and demonstration of the horizontal scrubbing method of brushing have a long-lasting effect on the patient. This reduces the need of frequent reinforcement sessions of plaque control programs when compared to chair side motivational tests and conventional plaque control measures.