Orhan 2011.

Study characteristics
Methods	Study type: RCT (4 parallel groups) Duration of trial: not mentioned in the study Duration of follow‐up: 7 days
Participants	Setting: Department of Endodontics, Near East University, Turkey Inclusion criteria: patients were required to present a minimal of 4 teeth with dentinal hypersensitivity; the selected individuals had similar sociocultural characteristics; the patients had more than 1 month dentine hypersensitivity and did not use other hypersensitivity methods such as toothpastes and tubules sealers to decrease the amount of dentine hypersensitivity; the clinical examination of the teeth involved in the study revealed no difference in terms of presence of restorations between test and control teeth Exclusion criteria: participants that presented parafunctional habits, gastric and/or emotional diseases, or frequent ingestion of acidic food as probable etiological factors for dentine hypersensitivity, were ruled out; patients who had dental pathology causing pain similar to cervical dentinal hypersensitivity (such as teeth with caries, the presence of orthodontic appliances and restorations, and/or the presence of a history of periodontal surgery in the area of the tooth during the previous 3 months, postoperative sensitivity), patients who had taken any medication, patients who received professional treatment with desensitizers in the previous 6 months, patients who received any treatment in past 30 days, those patients who were pregnant or lactating and patients who had any systemic diseases and/or the presence of a vital bleaching history; subjects whose test teeth had evidence of pulpitis, carious lesions, cervical fillings, defective restorations, facets of attrition, premature contact, cracked enamel or any other factor that could be responsible for sensitivity complaints, were also excluded Total number: 16 patients with 64 teeth enrolled and completed Age range: 21 to 51 years (mean age: 34.31 years) Sex (M/F): 8/8
Interventions	Participants were randomly distributed into 4 groups (n = 4) Group 1: Gluma desensitizer Details: in the first group, 2 layers of desensitizer (Gluma Desensitizer, Heraeus Kulzer, Armonk, NY) containing 2‐hydroxyethylmethacrylate, glutardialdehyde, and purified water were applied to ensure adequate desensitization. Care was taken to ensure that the desensitizer only came into contact with the area to be treated and the smallest possible amount required for the treatment was applied using disposable brushes for avoiding cross‐contamination and left for 60 s. Then the surface was carefully dried applying a stream of compressed air until the fluid film disappeared and the surface was no longer shiny. The surface was then rinsed thoroughly with water Group 2: GaAlAs laser (output 25 mW, wavelength 655 nm) Details: in the second group, a GaAlAs red wavelength low‐intensity diode laser (RJ Lasers, Vienna, Austria) was chosen for LLLT. The system delivers a 25‐mW output that emits a wavelength of 655 nm. The operator and the patient wore laser‐protective eyewear specific to the diode laser's wavelength during the treatments. The laser was applied to the dentine surfaces in continuous mode with contact on the region of exposed dentinal area for 160 s in each session per tooth, in a uniform, sweeping, and scanning motion. The calculated deposited energy density was 4 J/cm2 per dental element. Laser treatments were carried out in 6 sessions, with no intervals between sessions, during a period of 6 consecutive days Group 3: distilled water Details: in the third group, distilled water was used as the placebo group for the desensitizer Group 4: placebo laser Details: in the fourth group, the laser device was positioned but yet not activated
Outcomes	Responses to air blast stimuli (VAS with the value range between 0 and 100) at baseline, and 24 hours, 7 days after intervention
Notes	Baseline characteristics: 1. prior to desensitizing treatment, dentine hypersensitivity was assessed by a thermal/evaporative stimuli and patients' response to the examination was considered to be a control. Each patient had 4 incisors, canines, or premolars with exposed cervical dentine on the facial surface that could be affected when air was applied. Sensitivity was assessed by means of evaporative stimuli, a 5‐s cold air blast (temperature range of 19‐20℃) at a distance of 0.5 cm from the site to be tested. All stimuli were given by 1 operator at the same dental chair with the same equipment yielding similar air pressure and temperature each time; 2. all the stimuli were applied on the cervical region of the experimental teeth after removing supragingival plaque with a low‐speed handpiece with pumice powder and without fluoride. The adjacent teeth were isolated with cotton rolls and a suction device. The air stream was not extended longer than necessary to generate a response. The patients were given a VAS upon which they were asked to place a pencil mark at a point on a linear scale marked from 0 to 100 to describe the pain experienced. After each stimulus to the suspected site, the degree of hypersensitivity was determined from 0 to 100 as the baseline VAS score for each individual painful tooth. In order to standardize the sample, the criterion for inclusion in the study was a sensitive dentinal response of a minimum of 40 in the 0 to 100 numeric scale for pain evaluation, characterizing moderate cervical dentine hypersensitivity; 3. after recording the first scores, the subjects were randomly assigned to 1 of the treatment or the placebo groups. The subjects were blinded to the agent being used. The randomization process was conducted before the clinical steps and carried out by using sequentially numbered opaque sealed envelopes prepared with unrestricted (simple) randomization. Each treatment agent and placebo was written and sealed in envelopes before beginning the study. The dental operator who carried out all the treatments opened an envelope for each case at the beginning of the treatment Sample size calculation: not mentioned in the study. Source of funding: not mentioned in the study. Ethics approval: not mentioned in the study. Informed consent: quote: "Informed consent was prepared and obtained according to the Helsinki Declaration Ⅱ. The purpose and design of the investigation were explained and a consent form was signed by all of the participating patients" Adverse events: none
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "The randomisation process was conducted before the clinical steps and carried out by using sequentially numbered opaque sealed envelopes prepared with unrestricted (simple) randomisation" Comment: probably done
Allocation concealment (selection bias)	Low risk	Quote: "The randomisation process was conducted before the clinical steps and carried out by using sequentially numbered opaque sealed envelopes prepared with unrestricted (simple) randomisation. Each treatment agent and placebo was written and sealed in envelopes before beginning the study. The dental operator who carried out all the treatments opened an envelope for each case at the beginning of the treatment" Comment: probably done
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Quote: "The subjects were blind to the agent being used"
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote: "Treatments were performed by the same experienced operator and the pain was assessed by another person to minimize errors and to avoid bias" Comment: adequate
Incomplete outcome data (attrition bias) All outcomes	Low risk	No loss to follow‐up
Selective reporting (reporting bias)	Low risk	All intended outcomes were reported in the study
Other bias	Low risk	No other sources of bias were identified Sample size calculation, source of funding, and ethics approval were not mentioned in the study