Gentile 2004.

Study characteristics
Methods	Study type: RCT (2 parallel groups) Duration of trial: 8 to 11 weeks Duration of follow‐up: 6 to 8 weeks
Participants	Setting: Bauru Dental School, Brazil Inclusion criteria: complaint of sensitivity at the cervical part of the anterior and/or posterior teeth to current stimulus such as air, touch, sweet foods or brushing, with or without non‐carious cervical lesions and with gingival recession, independent of their length or wideness; good levels of oral hygiene, with an oral health condition that would allow precise diagnosis of dentine hypersensitivity; absence of serious systemic and psychological diseases; those using any analgesic or anti‐inflammatory medicines were oriented to not make use of it 6 hours before hypersensitivity treatment Exclusion criteria: exclusion of teeth presenting decays, cracks or fissures, large and unsatisfactory restorations, class V restorations, prosthetic elements and abutments of partial prosthesis under abnormal occlusion forces; without periodontal cysts and increased mobility; in cases submitted to periodontal surgery, a minimum period of at least 3 months was respected before treatment of dentine hypersensitivity; teeth should not have been submitted to dentine hypersensitivity treatment in the last 6 months Total number: 32 participants with 68 teeth Age range: 20 to 52 years Sex (M/F): 10/22
Interventions	Group 1: (16 patients, n = 35 teeth): AsGaAl diode (15 mW, 0‐15 J/cm2, 670 nm, tip: 4 mm2). The laser dosage applied to each tooth was 4 J/cm2 for a pre‐determined time of 2 minutes, according to calibration of the laser device. Laser was irradiated at 3 points on each tooth Group 2: (16 patients, n = 33 teeth): the control group were exposed to light cure (as placebo) for 30 seconds in an identical procedure. Treatments in both groups were rendered in 6 sessions with intervals from 48 to 72 hours
Outcomes	Sensitivity to tactile and thermal (air) stimuli was recorded before and 6 to 8 weeks after the final session of the treatment (VAS score)
Notes	Baseline characteristics: 1. all patients were submitted to an accurate anamnesis, in order to detect any systemic alteration, use of any medication, or psychological disturbances that could have been omitted at the initial report and that could be relevant for maintenance of the patient in the study. A second approach comprised questioning the patients about their current food habits, oral hygiene and about any periodontal treatments that could act as coadjutant factors triggering dentine hypersensitivity. However, no alteration regarding food habits was introduced, only concerning hygiene methods when the technique was considered traumatic; 2. determination of dentine hypersensitivity patterns: each selected tooth of each patient received 2 stimuli, namely a tactile with a #5 dental probe and an air jet, considered as a thermal‐evaporative stimulus. The first stimulus consisted in investigating all lesion extensions with the probe tip, which can lead to compression of the dentine, thus favouring motion of the dentine fluid, which activates the mechanoreceptors causing the painful sensation. The second stimulus, the air‐jet, was applied to the exposed dentine with an air syringe for 1 second, at room temperature and at a distance of 1 cm from the dentine surface. This stimulus can be considered a combination of thermal and evaporative stimuli, and this way 2 mechanisms operate to cause pain, namely the decrease in temperature at the dentine surface and fluid evaporation from some opened dentinal tubules, activating the hydrodynamic forces at the dentinal tubules and stimulating the painful sensation. An interval was allowed between the stimuli application, which was enough to avoid interferences between them. Measurement of sensitivity was performed after each stimulus by VAS Sample size calculation: not mentioned in the study Source of funding: not mentioned in the study Ethics approval: quote: "All patients participating in the study signed an Informed Consent Term, based on the Guidelines of the Ethics Committee of Bauru Dental School, 1998" Informed consent: quote: "All patients participating in the study signed an Informed Consent Term, based on the Guidelines of the Ethics Committee of Bauru Dental School, 1998" Adverse events: not mentioned in the study
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Insufficient information provided
Allocation concealment (selection bias)	Unclear risk	Insufficient information provided
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Due to the use of placebo laser, the study might be free of performance bias
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Insufficient information provided
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	No descriptions on 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 and source of funding were not mentioned in the study