Background: Dentin hypersensitivity (DH) is defined as high sensitivity of the vital dentin when exposed to thermal, chemical or tactile stimuli. Two mechanisms are required for the occurrence of DH: 1) the dentin must be exposed and 2) the dentinal tubules must be open and connected to the pulp. Molar-incisor hypomineralization (MIH) is a qualitative abnormality of a genetic origin that affects tooth enamel and, in most cases, is accompanied by DH. The control of tooth sensitivity is fundamental to the successful treatment of MIH.

Objective: The aim of the proposed randomized, controlled, clinical trial is to evaluate the effectiveness of different protocols for the control of DH in patients with teeth affected by MIH.

Methods: One hundred forty patients who meet the inclusion criteria will be allocated to four groups. Group 1 will be the control group (placebo). In Group 2, sensitive teeth will be sealed with Permaseal (Ultradent). In Group 3, sensitive teeth will receive low-level laser (LLL) (AsGaAl) at a wavelength of 780 nm (Laser XT Therapy, DMC, São Carlos, SP, Brazil). In Group 4, sensitive teeth will be treated with both LLL and Permaseal (Ultradent). DH will be evaluated 15 min after the application of the treatments and the patients will be reevaluated one week, one month, three months and six months after the treatments.

Discussion: This study will enable the determination of differences in the effectiveness of the proposed treatments as well as differences among the evaluation times for each proposed treatment.

Inclusion Criteria:

• Age between 18 and 35 years;
• Good overall health;
• At least one tooth with MIH and DH reported in the cervical region with sensitivity equal to or greater than 4 on the VAS.

Exclusion Criteria:

• Active caries or defective restorations on the tooth to be analyzed;
• Sufficient dentin loss that requires restorative treatment or periodontal surgery;
• Having undergone any professional desensitizing treatment in the previous six months;
• Having used a desensitizing paste in the previous three months;
• Use of anti-inflammatory drugs or analgesics at the time of recruitment;
• Currently pregnant or nursing.

The datasets (Excel spreadsheets) generated from this protocol will be available with the corresponding author (Sandra Kalil Bussadori - sandra.skb@gmail.com) at a reasonable request. However, reuse of this data will not be allowed for people who are not authors of this paper.

All volunteers and the evaluator of the degree of sensitivity will be blinded to the allocation. The researcher in charge of applying the products will not be blinded due to the different forms of clinical manipulation of the products.