Faculty Bibliography

The purpose of this study was to identify and quantify the availability of orthodontic literature for evidence-based clinical decision-making (ie, sound clinical studies of etiology, diagnosis, treatment, or prognosis meeting basic methodologic criteria for direct clinical use). This is a first step toward developing online decision analysis systems. A search strategy based on Medical Subject Headings (MeSH) for orthodontics was developed to examine MEDLINE using the Ovid Web Gateway search engine. Sensitive and specific methodologic search filters were then employed to identify the 4 categories of information. The results were then subdivided by year to identify trends and sorted to identify source of publications. In the period 1990 to 1998, the MEDLINE searches identified 6938 English-language articles about orthodontics. The mean number of articles (+/-SD) per year ranged from 42+/-25 for specific searches to 314+/-214 for sensitive searches. The number of articles identified by the specific or sensitive searches increased 14% to 21% annually. When subdivided by clinical category, the mean numbers of articles per year for specific and sensitive searches were respectively: etiology 19+/-15 and 91+/-37, diagnosis 11+/-5 and 80+/-35, therapy 3+/-1 and 50+/-23, and prognosis 10+/-7 and 93+/-33. Five dental journals accounted for nearly half of these publications. These results provide several key findings: (1) there is a substantial literature of clinically relevant information in orthodontics upon which to base clinical decisions; (2) the information appears to be balanced between etiology, diagnosis, treatment, and prognosis; (3) approximately 45% of the articles reside in 5 journals, whereas the remainder reside in approximately 66 other journals, making it difficult to stay current; (4) the number of articles is increasing significantly each year; (5) to stay current, one would need to read between 1 and 6 articles per week, 52 weeks per year; (6) these trends suggest the need for computer-based clinical knowledge systems; and (7) the methods used here can be immediately employed to identify the best and most current clinical orthodontic evidence.

INTRODUCTION: Common clinical experience suggests that tooth whitening agents are 100% effective. This study uses meta-analysis of data from published randomized controlled clinical trials to determine the efficacy of tooth whitening agents. METHODS: A MEDLINE search strategy was developed and implemented to systematically identify clinical trials on dentist-prescribed, home-applied tooth whitening agents, using 10% carbamide peroxide, published between 1989-1999. Inclusion criteria (e.g., in English, human clinical trials) and exclusion criteria (e.g., not placebo controlled) were established and clinical trials that met these criteria were critically appraised for validity and clinical applicability. Meta-analysis was then used to quantitatively integrate the findings. RESULTS: Seven studies were identified that met the inclusion and validity criteria. These studies indicated that: Whitening results in a significant mean change of 6 4 shade guide units (p < 0.01), while the placebo control group exhibited little change (0.7 0.6, p > 0.05). 93% of the bleached patients exhibited 2 shade guide unit change, while 20% of the placebo control group exhibited this change. The brand of bleaching agent had a significant effect on tooth whitening, but the daily application time and duration of treatment did not. Whitening is maintained for 6 months for 1/2 of the people treated. Neither gingival indices nor plaque indices were adversely or favorably affected by bleaching. CLINICAL APPLICABILITY: The data from the reviewed studies indicate that rather than being 100% effective, on average: 73% (93% for bleached group minus 20% placebo group) of people who whiten their teeth will exhibit a whitening that is 2 shade guide units greater than the placebo. 20% of the people who use dentist-prescribed, home-applied bleaching will achieve a mean whitening effect of 5 shade guide units. Re-treatment for 50% of people may be necessary to maintain this effect longer than 6 months. The methods used here are Internet applicable for other clinical topics.

The purpose of this study was to estimate the quantity of dental implant literature available on MEDLINE for evidence-based clinical decision-making and to identify its location. A search strategy based on Medical Subject Headings for dental implants was developed to examine MEDLINE using the Ovid Web Gateway search engine. Sensitive and specific methodologic search filters identified 4 categories of information: etiology, diagnosis, therapy, and prognosis. The results were then subdivided by year to identify trends and sorted to identify the sources of publications. The searches identified 4,655 articles published in English between 1989 and 1999 on human dental implants on MEDLINE. The mean number of articles (+/- SD) per year ranged from 15 +/- 11 for specific searches to 107 +/- 50 for sensitive searches. The number of articles increased by 14% to 43% each year for the sensitive search. When subdivided by clinical category, the mean numbers of articles per year for sensitive and specific searches were, respectively: diagnosis 12 +/- 7.5 and 1.5 +/- 1.6, etiology 58 +/- 33 and 1.9 +/- 2.5, therapy 23 +/- 15 and 0.3 +/- 0.5, and prognosis 67 +/- 33 and 12 +/- 8.3. Four dental journals account for approximately half of these publications. These results provide 6 key central findings: (1) there appears to be a substantial literature of clinically relevant information on implants upon which to base clinical decisions; (2) the implant literature is significantly biased toward articles addressing prognosis; (3) to stay current, one would need to read between 1 and 2 articles per week 52 weeks per year, and this number increases significantly each year; (4) approximately 50% of the articles were published in 4 journals, whereas the remainder reside in approximately 97 other journals, making it difficult to stay current; (5) these trends reaffirm the need for lifelong learning; (6) these trends also suggest the need for computer-based clinical knowledge systems.