Two independent reviewers screened the databases MEDLINE, EMBASE, the Cochrane Central Register of ControlledTrials, the National Research Register, and the Cochrane Oral HealthGroup'sTrials Register for articles written in English between 1977 and January1, 2010. The inclusion criteria comprised randomized controlled trials (RCTs) involving the application of laser desensitizing procedures and topical desensitizing agents in patients with at least 2 or more hypersensitive teeth confirmed by evaporative stimulus or tactile hypersensitivity assessment. Trial groups needed to receive laser therapy, whereas the control groups received topical desensitizing agents, such as fluoride varnish, dentin bonding agents, or others. Outcomes had to be measured by clinical performance (decrease of hypersensitivity) and/or patients' self-assessment. Studies with loss in follow-up greater than 20% or with confusing data/probable errors were excluded. A total of 176 potential relevant titles, abstracts, and articles were found, 28 of which were screened for further evaluation. Out of these, 8 trials met all inclusion criteria, involving a total of 234 patients. The quality of these trials was assessed according to the Cochrane Handbook for Systematic Reviews of Interventions. Accordingly, only 1 study was classified as A level, 5 as B level, and 2 as C level. A meta-analysis was not performed because of the heterogeneity of the studies.Studies that assess the application of laser desensitizing procedures in reducing dentinal hypersensitivity.The primary outcome was reduction of tooth sensitivity following treatment with either a laser or a topical desensitizing agent. Evaluations were made at varying intervals up to 6 months after treatment.Eight trials reporting on a total of 234 patients were included based on the specified criteria and 20 articles were excluded. Sample size in each of the included studies varied from 20 to 70 patients with differing follow-up intervals of up to 6 months. Most studies used Visual Analog Scale scores or other subjective tools to assess sensitivity. All 8 studies compared one kind of laser versus one kind of topical desensitizingagent. However, types of lasers as well as types of desensitizing agents differed among the reviewed studies. Half of the studies compared gallium-aluminum-arsenide (GaAlAs) lasers with various topical desensitizing agents; however, findings were conflicting. Two moderate-quality trials indicated that GaAlAs laser and the control desensitizing agents preformed similarly. Another moderate-quality trial demonstrated that the application of a bonding agent was significantly better than a GaAlAs laser in the reduction of hypersensitivity. The only reviewed study that was classified as an A-level study revealed a significantly greater immediate and long-term desensitizing effect than the control. The remaining studies involved Nd:YAG, Er:YAG, and CO(2) lasers, all of them reporting a slightly greater decrease in sensitivity as compared with topical desensitizing agents. Five of 8s tudies reported on the safety of laser application and did not find any detrimental pulpal effects, allergic reactions, or clinically detectable complications during follow-up.The authors concluded that the results obtained from the 8 studies included in this systematic review were conflicting but indicated a slight clinical advantage of laser therapy over topical medicaments in the treatment of dentin hypersensitivity. It was further concluded that application of lasers under controlled parameters for this indication may not lead to adverse effects.