Browsing by Author "Majeed, Abdul"

Now showing 1 - 9 of 9
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    A clinical study of the effectiveness of two different 10% carbamide peroxide bleaching products: a 6-month followup
    (Hindawi Publishing Corporation, 2011) Grobler, Sias Renier; Majeed, Abdul; Hayward, Roche; Rossouw, Roelof; Moola, Mohamad H.; van Wyk Kotze, Theuns
    The purpose of this study was to evaluate the efficacy of two different 10% carbamide peroxide bleaching products just after treatment and after a 6-month follow-up period. Methods. Two 10% carbamide peroxide products (Opalescence PF andNiteWhite ACP) were applied nightly for 14 days, according to the manufacturers’ instructions. The color of teeth 11 and 21 of thirty-four subjects having A2 or darker teeth were measured with a spectrophotometer (L∗; a∗; b∗) before treatment, just after treatment (14 days) and after 6 months. Results and Conclusions. Both products produced significant whitening of teeth with total color change (ΔE∗ ab) of approximately 5.20 units. There was a significant improvement in all 3 color coordinates (L∗, a∗, and b∗) for up to 6 months postbleaching (P < .05). Nite White showed a higher degree of relapse (27%) than Opalescence (18%) over the 6-month period. It is suggested that rebleaching after 6 months is not necessary
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    Effect of four different Opalescence tooth-whitening products on enamel microhardness
    (South African Dental Association, 2008) Majeed, Abdul; Grobler, Sias Renier; Moola, Mohamad H.; Rossouw, Roelof; van Wyk Kotze, Theuns
    OBJECTIVES: The purpose was to evaluate the effect of various Opalescence tooth-whitening products on enamel. METHODS AND MATERIALS: Enamel blocks were exposed to Opalescence PF 10% Carbamide Peroxide (n = 10), Opalescence PF 20% Carbamide Peroxide (n = 10), Opalescence Trèswhite Supreme 10% Hydrogen Peroxide (n = 10) and Opalescence Quick PF 45% Carbamide Peroxide (n = 10) according to the manufacturer's instructions. The control group was enamel blocks (n = 10) kept in artificial saliva. The values were obtained before exposure and after the 14-days treatment period. Enamel blocks were kept in saliva between treatments. Indent marks on enamel blocks were examined using the scanning electron microscope for treatment effects. RESULTS: All four different Opalescence products damaged enamel. The most damage was done when treated for a long period (112 hours). SEM images also showed damage to enamel by all 4 products. Opalescence with 10% and with 20% Carbamide Peroxide showed the highest damage, which also differed significantly (p < 0.05) from the saliva control group (p < 0.05; Tukey-Kramer Multiple comparison test). CONCLUSION: All 4 Opalescence products damaged enamel. Higher damage was done by the 10% carbamide peroxide and 20% carbamide peroxide products because of the much longer exposure period (112 hours in comparison to 7 hours).
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    Effect of four over-the-counter tooth-whitening products on enamel microhardness
    (South African Dental Association, 2011) Majeed, Abdul; Grobler, Sias Renier; Moola, Mohamad H.; Oberholzer, Theunis
    OBJECTIVES: This in vitro study evaluated the effect of four over-the-counter tooth-whitening products on enamel microhardness. METHODS: Fifty enamel blocks were prepared from extracted human molar teeth. The enamel surfaces were polished up to 1200 grit fineness and the specimens randomly divided into five groups. Enamel blocks were exposed to: Rapid White (n=10); Absolute White (n=10); Speed White (n=10) and White Glo (n=10) whitening products, according to the manufacturers' instructions. As control, ten enamel blocks were kept in artificial saliva at 37 degrees C without any treatment. Microhardness values were obtained before exposure (baseline) and after 1, 7 and 14-day treatment periods using a digital hardness tester with a Vickers diamond indenter. Data were analysed using Wilcoxon Signed Rank Sum Test, one-way ANOVA and Tukey-Kramer Multiple Comparison Test (p<0.05). RESULTS: Both Rapid White and Absolute White reduced enamel microhardness. Speed White increased the microhardness of enamel, while White Glo and artificial saliva had no effect on hardness. CONCLUSIONS: Over-the-counter tooth-whitening products might decrease enamel microhardness depending on the type of product.
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    Effect of various tooth-whitening products on enamel microhardness
    (South African Dental Association, 2009) Grobler, Sias Renier; Majeed, Abdul; Moola, Mohamad H.
    Objectives: The purpose was to evaluate the effect of various tooth-whitening products on the South African market, containing carbamide peroxide (CP) or hydrogen peroxide (HP), on enamel microhardness. Methods: Enamel blocks were exposed to: Nite White® ACP 10% CP (group 2, n=10); Yotuel® Patient 10% CP (group 3, n=10); Opalescence® PF 10% CP (group 4, n=10); Opalescence® PF 20% CP (group 5, n=10); Opalescence® Treswhite Supreme 10% HP (group 6, n=10); Yotuel® 10 Minutes 30% CP (group 7, n=10); Opalescence® Quick 45% CP (group 8, n=10), Yotuel® Special 35% HP (group 9, n=10), Opalescence® Boost 38% HP (group 10, n=10) according to the instructions of the manufacturers. The control group (1) was enamel blocks (n=10) kept in artificial saliva at 37˚C without any treatment. The microhardness values were obtained before exposure and after a 14-day treatment period. Specimens were kept in artificial saliva at 37˚C between treatments. Data were analysed using Kruskal-Wallis one-way ANOVA and Tukey-Kramer Multiple Comparison Test. Indent marks on the enamel blocks were also examined under the scanning electron microscope. Results: All whitening products decreased enamel microhardness except group 10. Only Groups 2,3,4,5 and 7 showed significant decrease in enamel microhardness as compared to the control group (p<0.05). Groups 2, 3 and 7 differed significantly from all the other groups (p<0.05). The highest damage was recorded for group 2 (Nite White® ACP 10% CP), which differed significantly from groups 3 and 7. SEM images also showed damage to enamel. Conclusions: All products damaged enamel except Opalescence® Boost 38% HP. In general, the products containing carbamide peroxide were more damaging while longer treatment periods influenced the microhardness values negatively. Nite White® ACP without fluoride showed relatively more damage than all the other products containing fluoride.
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    An in vitro study of microleakage and surface microhardness of nanocomposite restorative materials
    (University of the Western Cape, 2005) Majeed, Abdul; Osman, Yusuf I.; Dept. of Restorative Dentistry; Faculty of Dentistry
    The demand for posterior aesthetic restorations has dramatically increased in recent years. Several new materials have been developed with improved aesthetic, adhesive and mechanical properties. However, microleakage elimination, especially if the margins are on dentine or cementum, and attainment of optimum mechanical properties for posterior use, are still questionable. The aim of this study was to investigate microleakage and surface microhardness of a nanofilled, a nanohybrid and an ormocer based nano-ceramic composite restorative material.
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    In vivo spectrophotometric assessment of the tooth whitening effectiveness of Nite White 10% with amorphous calcium phosphate, potassium nitrate and fluoride, over a 6-month period
    (Bentham Science Publishers, 2011) Grobler, Sias Renier; Majeed, Abdul; Moola, Mohamad H.; Rossouw, Roelof; van Wyk Kotze, Theuns
    To clinically evaluate the effectiveness of Nite White 10% carbamide peroxide with amorphous calcium phosphate, potassium nitrate and fluoride over a 6-month follow-up period. Nite White was applied nightly for 14 days, according to the manufacturer’s instructions. The color of teeth 11 and 21 of twenty one subjects was measured with a spectrophotometer (L*; a*; b*). Subjects were instructed to take note of any tooth sensitivity and gingival irritation. For all three components (L*, a* and b*) statistical significant differences (p<0.05) in the values between base-line (prebleaching) and; after treatment, after 1-month, after 3-months as well as after 6-months were found (Wilcoxon Signed Rank Sum Test). Significant differences were also found amongst the 􀀁E*ab (0-14days) values and; 􀀁E*ab (0-1 month), 􀀁E*ab (0-3 months) and 􀀁E*ab (0-6 months). However, no significant differences were found between pairs of 􀀁E*ab (0-1 month), 􀀁E*ab (0-3 months) and 􀀁E*ab (0-6months). The decrease in 􀀁E*ab was the highest after 1 month (~30%). The highest decrease in L* was about 58% after 1 month. Over the 14-day treatment period tooth sensitivity was 24.5%. Conclusions: Nite White ACP demonstrated significant tooth-whitening (unit increase = 5.29) with a low tooth sensitivity (25%) probably due to the presence of amorphous calcium phosphate, potassium nitrate, and fluoride. The whitening effect decreased the most after one month and then maintained well even after a 6 month period (units 3.89).
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    An in-vitro analysis of the antimicrobial efficacy of herbal toothpastes on selected primary plaque colonizers
    (iMD Publishers, 2011) Peck, Mogammad T.; Africa, Charlene W.J.; Stephen, Lawrence X.G.S.; Marnewick, Johan; Majeed, Abdul
    Plaque associated oral disease affects a considerable portion of the population and is considered one of the major causes of tooth loss. In most cases toothbrushing only removes a limited amount of dental plaque and other chemical agents are required to reduce the bacterial load. Aims & objectives: The purpose of study was to determine whether there was any significant difference in the antimicrobial activity of 4 herbal toothpastes against cultures of 3 primary plaque colonizers. Methods: A total of 5 toothpastes were tested for their antimicrobial efficacy against Streptococcus mutans (NCTC 10920), Streptococcus sanguinis (NCTC 10904) and a non-specific α-heamolytic streptococcus by agar diffusion method. The data were collected and analysed using one way ANOVA and Tukey’s multiple comparison test significant at p<0.05. Results: Dentazyme® herbal toothpaste showed the greatest ability to inhibit bacterial growth for all the tested organisms (p<0.05). Nature Fresh had the lowest potential for antimicrobial activity. Conclusions: Dentazyme® Herbal toothpaste was the only herbal toothpaste to inhibit the growth of all the bacteria tested and had similar antimicrobial efficacy to a triclosan containing toothpaste (Colgate® Total®).
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    The pH of various tooth whitening products on the South African market
    (South African Dental Association, 2011) Majeed, Abdul; Grobler, Sias Renier; Moola, Mohamad H.
    OBJECTIVES: The purpose of this in vitro study was to investigate the pH of 21 commercially available tooth-whitening products. METHODS: Tooth-whitening products were divided into four categories: dentist supervised-home bleaching products (n = 5); in-office bleaching products (n = 5); over-the-counter bleaching products (n = 4) and whitening toothpastes and rinses (n = 7). The pH of three samples of each product was measured using an Orion Expandable Ion Analyzer EA940 with a Sure-Flow, Epoxy-body combination pH electrode. The group data were analysed using one way ANOVA (significant at p < 0.05). RESULTS: The five dentist supervised-home bleaching products had a mean pH of 6.21 +/- 0.76 and ranged from 4.88 to 6.81. The five in-office bleaching products had a mean pH of 6.26 +/- 1.19 and ranged from 5.30 to 7.85. The four over-the-counter whitening products had a mean pH of 5.07 +/- 1.74 and ranged from 3.76 to 8.03 and the seven whitening toothpastes had a mean pH of 7.66 +/- 1.19 and ranged from 6.61 to 9.68. The pH of the over-the-counter category was significantly lower (more acidic) than all other categories (p < 0.05). The whitening gel of Rapid-White had the lowest acidic pH of 3.76 and Colgate Advanced Whitening toothpaste showed the highest alkaline pH of 9.68. CONCLUSIONS: The pH of all tooth-whitening products showed a wide range from 3.76 (highly acidic) to 9.68 (highly alkaline). Over-the-counter whitening products showed the lowest pH levels and in general these can be expected to damage enamel more than the other products. Dentists should be vigilant with regards to products used outside their surgeries and should warn their patients accordingly. CLINICAL IMPLICATIONS: The acidic pH of many of the whitening products other than in-office bleaching products is of concern and the general public should be better informed by the dental professionals of the dangers of these products.
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    Platelet - Rich Fibrin (PRF) - The effect of storage time on platelet concentration
    (South African Dental Association, 2015) Peck, Mogammad T.; Hiss, Donavon; Stephen, L.; Satti, A.; Majeed, Abdul
    The aim of this study was to determine whether storage time had a significant effect on the platelet concentration of platelet-rich fibrin (PRF). Three blood samples were drawn from each participant into a sterile blood sampling tube. Two of the blood samples were centrifuged to form PRF. The third non-centrifuged sample was used to measure the baseline blood platelet concentration. After PRF had formed, it was removed from the respective test tubes at different time intervals i.e. immediately after centrifugation (Group A) and after 60 min of storage time in the blood collecting tube (Group B). The residual blood from each group was tested for platelet concentration and compared with the baseline reading (as an indirect measure of the platelet concentrate of PRF). The PRF produced in Group A (PRF A) had a mean platelet concentration of 274 + - 57.8 X 109/L, whereas the PRF of Group B (PRF B) was 278 + - 58.2 X 109/L. A statistically significant difference was seen between the groups (p < 0.001).