
The purpose of this study was to evaluate the effect of Colgate Platinum Professional Toothwhitening System on the microhardness of enamel, dentin, and two composite resins. This in vitro study replicated conditions in the oral cavity and followed the prescribed procedure for whitening teeth. The results of this study showed no significant differences in the microhardness of the control and treated teeth or the composite restorations tested. This indicates that the use of Colgate Platinum will not soften teeth or the composite restoratives studied.
A 2-week study was conducted to evaluate the tooth-whitening efficacy of Colgate Platinum Professional Toothwhitening System vs Rembrandt Lighten Bleaching Gel. Thirty-eight subjects completed this single-blind, randomized, parallel clinical study. The subjects were balanced into two groups based on a minimal shade of A3 on the Vita shade guide. The duration of product use was 30 minutes, twice daily for 2 weeks. Change in toodth color was measured by reflectance spectroscopy using a colorimeter. The readings were taken in the L*, a*, and b* color space at the initiation of the study, at 1 week, and at 2 weeks. Calculation of color change (deltaE) was performed using the color difference equation established by the Commission International de L'Eclairage. Results demonstated that Colgate Platinum was 46% more effective at tooth whitening after 1 week, and 96% more effective after 2 weeks of treatment. The results demonstrated that the Colgate product was significantly superior vs Rembrandt at increasing tooth whiteness (increase in deltaE), and tooth lightness (increase in deltaL*). No adverse reations were noted on clinical examination.
A 2-week, three-cell study was conducted to evaluate the tooth-whitening efficacy of the Colgate Platinum Professional Toothwhitening System vs Rembrandt Gel Plus (a regimen of products consisting of a 10% carbamide peroxide gel, a whitening toothpaste, and a mouthrinse), and a placebo paste. Seventy subjects completed this parallel, single-blind, three-compartment, randomized clinical study. The subjects were balanced into two groups based on a minimal shade of A3 on the Vita shade guide and assigned a product. The duration of product usage was 1 hour twice daily for 2 weeks. Change in tooth color was measured by reflectance spectroscopy using a colorimeter. The readings were taken in the L*, a*, b* color space at the initiation, at 1 week, and at 2 weeks of the study. Calculation of color change (delta E) was performed using the color difference equation established by the Commission Internationale de L'Eclairage. Visual evaluation of shade changes was performed using the Vita shade guide. Results from this clinical study showed that Colgate Platinum was 77.7% more effective at tooth whitening after 1 week and 41.8% more effective after 2 weeks of treatment vs the Rembrandt regimen. Results showed that the Colgate product is significantly superior vs Rembrandt at increasing tooth whiteness (increase in delta E). Shade guide changes showed an overall improvement of 7.08 Vita tabs for the Colgate product and 5.12 Vita tabs for the Rembrandt regimen.
A 2-week study was conducted to compare the tooth-whitening efficacy of two 10% carbamide peroxide products: Colgate Platinum Professional Toothwhitening System and Rembrandt Lighten Bleaching Gel. Fifty subjects were divided into two groups and assigned a product to use for 2 weeks. Change in tooth color was measured by reflectance spectroscopy at the initiation of study, at 1 week, and at 2 weeks into the study. Color change was calculated using the color-difference equation established by the Commission International de L'Eclairage. Results showed that Colgate Platinum was 62% more effective at tooth whitening after 1 week and 83% more effective after 2 weeks of treatment vs Rembrandt. At the termination of the study, the mean color difference (deltaE) for Colgate Platinum was 4.29 and 2.34 for Rembrandt. Statistical analysis demonstrated that the Colgate product is significantly superior at increasing tooth whiteness, increasing tooth lightness, reducing redness, and reducing yellowness. In this study, no adverse reactions were noted on clinical examination and none were reported by panelists with normal healthy dentition.
A new approach to assess color change in teeth involves application of the Minolta CR-221 Chroma Meter. The process has been assessed in vitro by Dr. Stephen Rosenstiel of Ohio University and by Dr. Robert Seghi of the University of California School of Dentistry. The purpose of this study was to develop a technique to assess the tooth-whitening effects of peroxides on teeth in vivo, using a small-area colorimeter. Twenty male and female subjects participated. Study casts were made from alginate impressions. Two maxillary, white, polyvinyl siloxane, custom-postioning splints were fabricated for each subject. Each splint was modified to accept exactly the head of the colorimeter to a window exposing the middle one third of the facial surface of one central incisor. The coloimeter converts all colors within the range of human perception into a common numerical code. The use of the positioning splint allowed the researchers to reposition the colorimeter precisely for multiple reading each time measuremehts were taken. The color parameters were recorded in the L*a*b* color space. This method shows that multiple measurements on the same subject are consistent and statistically accurate. The standard deviation for L* (lightness) values was 0.22. This technique showed quantitatively the whitening effect on teeth to be increase in L* and a decrease in a* (red) and b* (yellow). The mean color difference (deltaE) for the 3-week study was 5.07.
Colgate Platinum, a professional tooth-whitening paste containing 10% urea peroxide as the active ingredient, was evaluated for potential acute oral toxicity, genotoxicity, and irritation to oral mucosa. Oral administration to rats of a single dose of 5 g/kg of Colgate Platinum did not induce any adverse effects. Colgate Platinum was not mutagenic in Ames/Salmonella Plate Incorporation assay and did not induce primary DNA damage in the bone marrow hematopoietic cells of rats that were given oral doses of up to 1 g/kg for 5 consecutive days. Results of the oral mucosa irritation study in rats indicated that Colgate Platinum did not induce damage to soft and hard tissues of oral cavity after repeated applications for 28 days. Collectively, the data from these studies document the safety of the product for the intended use.
Tooth-bleaching procedures became widely available with the 1989 introduction of a dentist-home technique. Over-the-counter home systems were put on the market shortly thereafter, but safety concerns led to a sales ban by the Food and Drug Administration (FDA) in 1991. That ban has been lifted while companies continue to supply information to the FDA. Information on bleaching safety has often been skewed because the high 35% hydrogen peroxide concentration used in the dentist-office procedures has sometimes been compared out of context with dentist-home formulas with 10% to 15% carbamide peroxide or 1% to 10% hydrogen peroxide. Earlier studies have also failed to put the risk level of tooth bleaching into perspective with other routine dental procedures. More recent studies show that 10% carbamide peroxide is safe when appropriately administered. Haywood does state that there is a risk level in any type of bleaching, and that the dentist-home system provides the best way to minimize the risk because the dentist can: (1) diagnose any problems or special needs; (2) plan appropriate treatment; and (3) fabricate, fit, and adjust the prosthesis used to apply the formula. A success rate of 96% (excluding tetracycline stain) has been achieved. Currently, most marketed systems use a carbamide peroxide in a thickened glycerin base. A new product is being introduced with 10% carbamide peroxide, a peroxide stabilizer, a thickener, and tooth-cleansing technology ingredients.
The Periodontal Disease Research Center at the State University of New York at Buffalo has studied two sets of subjects--those with a high prevalence of diabetes (the Pima Indians) and an urban population in Erie County, New York--to determine factors that put a patient at risk for periodontal disease. These and other studies have established that smoking and diabetes are important risk indicators for periodontal disease. Local etiologic factors associated with periodontal disease in adults include the presence of the putative periodontal pathogens Porphyromonas gingivalis and Bacteroides forsythus. Longitudinal studies and intervention studies are needed to fully establish the role of risk indicators. However, information already available from present studies suggests that modulation of risk factors, such as smoking and diabetes mellitus, as well as suppression of the pathogenic flora, will be effective in the management of periodontal disease.
Studies have indicated the heterogeneity of periodontal diseases and have suggested several pathogens that may play important etiologic roles. The risk associated with individual pathogens or combinations of pathogens has been assessed, and diagnostic tests have been developed for their detection in clinical practice. Strategies are being devised to improve treatment by using appropriate agents to control different periodontal infections.
Periodontal tissue repair and regeneration are regulated by the local production of growth factors. However, naturally produced growth factors may not be sufficient to optimally stimulate periodontal regeneration. Exogenous growth factors can be used to supplement natural growth factors in wound healing. The authors focus on describing the mechanisms of five growth factors in periodontal regeneration: platelet-derived growth factor; fibroblast growth factor; transforming growth factor-beta; insulinlike growth factor; and bone morphogenetic protein. The objective is to encourage strategies to exploit growth factors in the stimulation of cells in periodontal regeneration, which should result from continued in vivo animal studies.
As the scope of the acquired immunodeficiency syndrome (AIDS) epidemic grows to include increasingly larger proportions of heterosexual adults and children, there has also been a change in the severity of human immunodeficiency virus (HIV)-related periodontal conditions at one San Francisco clinic. The cases of HIV-associated gingivitis, now called linear gingival erythema, HIV-associated periodontitis (or necrotizing ulcerative periodontitis), and necrotizing stomatitis have been less severe, despite an increase in overall HIV caseload. No clear basis for this trend has been established, but possible explanations include: biased population samples, increased immunosuppression as the disease matures, use of antimicrobial therapy, or a change in patient demographics. Several studies have failed to identify a single causative organism. This article presents a review of HIV-related periodontal complications and points out that the condition can be treated with local and systemic antibiotics and that dental professionals throughout the world can expect a tremendous increase over the next several years in HIV-infected patients with special clinical complications.
Patients' desire for more esthetic smiles has prompted the development of periodontal regenerative techniques. Case reports of periodontal therapy in the form of subepithelial connective-tissue grafts and socket retention for problems such as deformed ridges, exposed root surfaces and uneven smile lines will be presented in this article.
Research indicates that human periodontitis is caused by bacteria. Although the roles of host factors are not clear, these factors are important in the development of this disease. The immune response that occurs in patients with infectious diseases, and that eventually arrests the process of the infection, does not appear to happen in patients with periodontitis. This article presents the results of studies that attempted to determine if periodontitis patients mount a humoral response during the course of their infection, if the antibodies produced are protective, and, if not, why these reactions fail to occur or why they are ineffective in halting the disease.
Alveolar ridge defects from bone loss hinder esthetics during conventional restoration and preclude optimal positioning of implant fixtures for implant-supported restorations. Various methods of ridge augmentation to replace lost bone can remedy these complications. Recent advances in periodontology have enabled clinicians to address the problems of ridge augmentation in various ways. This article describes these methods, which include soft-tissue rearrangement, soft-tissue grafting, hard-tissue implantation, and alveolar bone regeneration.
Dr. Henry M. Goldman's contributions to periodontics are many, but none may be as significant as the work he did in the study of antimicrobial agents used to fight periodontal disease. This article presents a review of the literature on antimicrobial effectiveness of chlorhexidine gluconate and describes its role as a chemotherapeutic, antibacterial, antiplaque agent.
Periodontal disease is one of the most common dental health problems in the United States. The treatment and prevention of periodontal diseases are now important aspects of dentistry. An increasing awareness has opened the marketplace for the development of new periodontal products. This article examines two general approaches to periodontal disease treatment, as well as advances in research and therapy.
Despite anecdotal reports that challenge hydroxyapatite (HA)-coated implant survivability, the experience in the placement of these implants over 9 years at Loma Linda University School of Dentistry has been favorable. The results of these implant placements are presented and analyzed in this article. After 7 years, the survival rate of HA-coated custom and stock blade-form implants is 97%. At 5 years, the survival rate for all upper HA-coated root form implants is 98%, and for all HA-coated implants placed in the lower jaw it is 99%. For implants placed in maxillary type 4 bone, there was a 32.6% failure rate among uncoated implants, but a rate of 14.9% in HA-coated implants. The causes of implant failure are often related to factors other than the type of implant, such as iatrogenic factors and poor oral hygiene.
Numerous studies have found hydroxyapatite (HA) to be a favorable material for dental implant coatings. Quality HA-coated implants have been shown to heal faster, attach more completely to the bone, and resist flaking and dissolution. However, as with natural teeth, good oral hygiene and proper professional maintenance are essential. To ensure the success of the implant, clinicians must understand that HA coatings vary according to thickness, porosity, attachment strength, and crystallinity, and must recognize the essential features of a quality coating.
An oral and maxillofacial surgery practice placed and evaluated 690 hydroxyapatite-coated dental implants from 1985 to 1993. Many implants were placed in patients with compromised conditions, such as lack of bone height or width. Advanced surgical procedures were used. Factors that were considered in assessing the success of the implants included anatomic position, sex of the patient, and length of the implant. The study showed that although shorter implants were more likely to fail than longer implants, the cumulative survival rate up to 88 months was 96.5%.
Controversy exists concerning the integrity of hydroxyapatite-coated implants over time. The Louisiana State University Oral and Maxillofacial Surgery Department studied data of 1,374 HA-coated implants that were placed from 1985 to 1991. Data were examined according to life-table survival, interval success rate, reasons for failure, and long-term effects. The rate of integration for HA-coated implants was found to be superior to that of noncoated, titanium implants. The HA-coated implants also showed excellent survival and function rates.