Kathy Shafer DMD
Review conclusion: A review of selected systematic reviews(SR's) comparing dental lasers with other restorative dental treatment concluded the overall quality of the evidence was low due to incomplete methods of reporting in the studies within the included reviews.
Critical summary conclusion: Based on results from seven selected systematic reviews comparing dental lasers with other restorative procedures, this systematic review found most of the included reviews lacked information needed to make sound treatment decisions regarding the use of lasers in restorative dentistry.
Clinical question: For patients requiring restorative dentistry, are dental lasers more effective than other dental procedures?
Review methods: Two investigators independently searched four databases from 1966 to 2007. The search included systematic reviews about laser usage in restorative dentistry and excluded those that were nonspecific about restorative laser usage. The authors excluded publications in languages other than English, Spanish, Portuguese, Italian, and German. The authors used the overview quality assessment questionnaire (OQAQ) to evaluate the scientific or methodological quality of the reviews. The OQAQ is the only validated instrument available to grade the methodological quality of systematic reviews. The OQAQ evaluates the following nine parameters: Was the search method used to find evidence on the primary question stated? Was there a methodological search? Was inclusion criteria reported? Was selection bias avoided? Was the criteria used for assessing the validity of the reviews selected reported? Was the validity of all the studies referred to in the text assessed using appropriate criteria? Was the method of combining the findings reported? Was there appropriate combining of the results? Was the conclusion made by the authors supported by the data? Designations were given to each parameter as "yes," they clearly met the criteria; "no," they did not meet the criteria; and "partially," when it was unclear or partially met the nine criteria. The parameters were evaluated using a ratings scale of one to seven (1 = major flaws, 7 = no flaws), and then averaged for a final score. A score of four or fewer indicates the review had major flaws and five or more indicates minimal flaws.
Main results: The search yielded 145 references, of which the authors eliminated all but 12. They obtained full-text articles of the references and seven reviews met all the inclusion criteria. The articles were published in dental journals from 2001 to 2007, the number of studies included in each systematic review ranged from four to thirty-nine , and the number of laser studies ranged from two to twenty-five. Two of the systematic reviews evaluated in vivo studies. Almost 72 percent (71.4 percent) of the included reviews evaluated the use of lasers for dental caries diagnosis. The included systematic reviews had conducted comprehensive literature search and assessed the included studies for bias and validity. The review was weakened by a methodology that combined findings to reach a conclusion, possible appropriation of this methodology, and conclusions not supported by the data. Fifty-seven percent of the systematic reviews had OQAQ scores lower than or equal to four, which indicates major flaws. The average score was 4.4.
Conclusions: Each of the included reviews lacked a detailed description of its methodology; thus, the overall quality of this review was low. Laboratory studies indicated that laser systems have important and useful clinical indications in dentistry; however the lack of sound methodology in these studies makes it difficult to assess and compare treatment options. More studies that meet international standards should be conducted to enable the comparison of different treatments and their outcomes.
Source of Funding:
Supported by the Brazilain Council of Science and Technology
Importance and Context:
Importance and Context: The technology of lasers for use in restorative dentistry continues to evolve. As study reports generate data about this alternative treatment option, clinicians should critically appraise the evidence level and methodological quality of those reports before using this technology.
Strengths and Weaknesses of the Systematic Review:
Strengths and Weaknesses of the Systematic review: Two authors searched the literature and applied explicit inclusion and exclusion methodology when evaluating the systematic reviews. The authors used OQAQ, the only validated instrument available to grade the methodological quality of the systematic reviews. The nine interrogatory parameters of this assessment tool evaluate the scientific or methodological quality in adherence to scientific principles. The authors noted that the language limits of their search strategy and their failure to include a reference list of the identified articles may have affected their results. The authors stated their rationale for excluding 133 of the original 145 references.
Strengths and Weaknesses of the Evidence:
Strengths and Weaknesses of the Evidence: The studies included in the reviewed systematic reviews evaluated different parameters, and used different techniques and methods to assess the same treatment applications, all of which introduced heterogeneity. The studies were deficient in the complete description of important methodological characteristics. The overall quality of the evidence was low. Only five clinical studies were identified by the selected systematic reviews. The majority of studies used samples of extracted teeth in a laboratory setting. Also, most of the studies evaluated lasers in the diagnosis of dental caries.
Implications for Dental Practice:
Implications for Dental Practice: This systematic review identified seven systematic reviews that compared lasers to other dental restorative treatments. The studies included in the systematic reviews were of low quality, which hinders a comparative assessment with other restorative procedures. More research is needed on the use of lasers in restorative dentistry procedures