Compendium (Newtown, Pa.). Supplement最新文献

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.

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.

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.

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.

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.

This study was conducted to test the effectiveness of the counter-rotational powered toothbrush in a nursing home environment. A group of 60 nursing home patients were selected; each was assigned to a specific trained toothbrusher. Participants were divided into two groups stratified by gingival inflammation in a crossover-design clinical trial. Each individual used the powered brush for one 4-week period, and a manual or conventional brush for another 4-week period. A suitable period of nonintervention separated the two 4-week periods of intervention to allow plaque and gingival scores to revert to baseline. The participants were evaluated for plaque and gingivitis before and after each brushing period. The experimental brush reduced both plaque and gingivitis more effectively than the conventional brush. The mean reduction in plaque scores was 1.44 for the conventional brush, 1.92 for the powered brush (Quigley-Hein Plaque Index). The mean reduction in gingival inflammation scores was 0.47 for the conventional brush, and 0.77 for the experimental brush (Löe and Silness Gingival Index). Participants perceived the counter-rotational powered brush to be more effective, and at the exit interview overwhelmingly preferred to keep it rather than the conventional brush.

Various studies have shown that noncoated, metallic screw-type implants have been highly successful in types 1, 2, and 3 bone. However, in type 4 bone, such as that found in the maxilla, these implants have not been as successful. In the maxilla, HA-coated implants have shown better results than noncoated implants, particularly with regard to bone-to-implant contact, shear strength, and fixation. The author therefore concludes that the HA-coated implant may have better long-term success when shorter implants are needed, and when treating patients with poor, low density, and cancellous bone.

Thirty clinical recall patients from the University of Missouri at Kansas City School of Dentistry participated in a 4-week study to determine the long-term effectiveness of the INTERPLAK Home Plaque-Removal Instrument compared to manual brushing and flossing. Patients were divided into two groups, with each group using the INTERPLAK device for 2 months and the manual brush for 2 months. Patients were assessed according to measured indices for plaque, bleeding, crevice depth, and calculus. The study found that both kinds of brushes significantly reduced plaque, bleeding, and crevice depth; however, only the INTERPLAK brush reduced calculus. Improvements on all indices were greater for the INTERPLAK device than they were for manual brushing and flossing. At the end of the 4 months, most patients indicated that they would continue to use the INTERPLAK device.

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.