Contents lists available at ScienceDirect Journal of Dentistry journal homepage: www.elsevier.com/locate/jdent A long-term evaluation of experimental potassium oxalate concentrations on dentin hypersensitivity reduction: A triple-blind randomized clinical trial Alexia da Mata Galvão, Livia Fávaro Zeola, Guilherme Faria Moura, Daniela Navarro Ribeiro Teixeira, Ramon Corrêa de Queiroz Gonzaga, Gisele Rodrigues da Silva, Paulo Vinícius Soares ⁎ Department of Operative Dentistry and Dental Materials, School of Dentistry, Federal University of Uberlândia, Uberlândia, Minas Gerais, 38400-902, Brazil ARTICLE INFO Keywords: Dentin sensitivity Desensitizing agents Potassium oxalate Randomized clinical trial ABSTRACT Objective: The aim of this split-mouth, triple-blind, randomized clinical trial was to evaluate the long-term clinical efficacy of experimental potassium oxalate concentration (10%) in relieving dentin hypersensitivity (DH), after a four-session application protocol. Methods: Potassium oxalate gels with different concentrations (5 and 10%) were randomly assigned to half of the 31 patients from the sample in a split-mouth design. The desensitizers were applied following a four-session protocol, one session every 48 h. The primary outcome was the assessment of pain level with the visual analog scale (VAS, 0–10), at baseline, immediately after each desensitizing session, and also after the seventh day and along 1-,3-, 6-, 9- and 12-months follow-ups. Statistical analyses were performed using Friedman repeated measures and Wilcoxon signed rank tests (α = 0.05). Results: For both groups, the minimum of three sessions were required for the achievement of lower DH levels. Regardless of the concentration, the desensitizing effect was maintained all the way to the end of the 6-month follow-up. The 10%-potassium oxalate group was more effective for both 9 and 12-months follow-up periods (p < 0.001). No complications and adverse effects were observed. Conclusions: When a four-session protocol is applied, both concentrations of potassium oxalate (5 and 10%) proved to be effective on DH reduction for up to six months. However, the higher concentration promoted better long-term results. Clinical Significance: The DH is an increasing condition in clinical practice, which affects the patient’s life quality. This study provides primary clinical evidence, suggesting that multiple application sessions and higher concentrations of potassium oxalate may result in maintenance of the desensitizing effect for more extended periods. Trial registered under number: ClinicalTrials.gov NCT03083496. 1. Introduction Over the last decades, the public health strategies and technological developments have led to the improvement of individuals’ quality of life and to an increase in life expectancy [1,2]. This situation, associated with the awareness of the population concerning of oral hygiene, is promoting the maintenance of natural teeth in the oral cavity for a longer period [1,2]. In addition, the reduction in the incidence of caries (due to successful oral health prevention strategies), daily stressful routine and new eating habits (acidic and industrialized products) have led patients to seek treatment for diseases that are not related to mi- croorganisms, such as noncarious cervical lesions and dentin hy- persensitivity (DH) [3]. The DH is characterized as a brief and sharp pain caused by thermal, chemical, tactile, and evaporative stimuli. To date, several data sup- ports a theory (hydrodynamic) that these types of stimuli can induce the flow of fluids inside the dentinal tubules, which triggers receptors near the pulp (mainly A-delta fibers) and results in painful sensations for the patient [4,5]. The prevalence of DH is considerably wide in adult populations, ranging from 1.3% [6] to 92.1% [7,8] and its etiology is https://doi.org/10.1016/j.jdent.2019.103180 Received 1 April 2019; Received in revised form 8 July 2019; Accepted 9 August 2019 ⁎ Corresponding author. E-mail addresses: alexiamgalvao@gmail.com (A.d.M. Galvão), liviazeola@gmail.com (L.F. Zeola), guifamo@gmail.com (G.F. Moura), dnrteixeira@gmail.com (D.N.R. Teixeira), ramonfoufu@gmail.com (R.C.d.Q. Gonzaga), giselerosilva@yahoo.com.br (G.R. da Silva), paulovsoares@yahoo.com.br (P.V. Soares). Journal of Dentistry xxx (xxxx) xxxx 0300-5712/ © 2019 Elsevier Ltd. All rights reserved. Please cite this article as: Alexia da Mata Galvão, et al., Journal of Dentistry, https://doi.org/10.1016/j.jdent.2019.103180