Background:
Among adults, dentine sensitivity (DS) prevalence remains between 4% to 69%, caused due to an array of aetiological factors resulting in exposure to dentine. The most widely accepted cause of pain associated with DS is the hydrodynamic theory of hypersensitivity whereby a stimulus being applied to dentin causes movement of tubular fluid leading to the activation of mechanoreceptors hence eliciting pain and discomfort. A recently introduced technique; the guided formation of enamel-like fluorapatite layers on a mineral substrate (BIMIN) has shown to have the potential to remineralise superficial enamel and/or exposed dentine.
Aims:
The aim of this study was to evaluate BIMIN in patients with moderate to severe DS.
Methods:
An examiner-blind, two-arm, randomised controlled 12-month study was conducted in 40 patients with DS. The participants were recruited from patients of the Department of Conservative Dentistry, Jena University Hospital (Germany).
Inclusion criteria: Presence of at least one sensitive tooth that resulted in a Visual Analog Scale (VAS) score >50mm, and exposed dentine in the cervical region (with or without wedge edge defects)
Exclusion criteria: <18 years, known allergies to materials used in the study, systemic diseases, pulpitis, and moderate or more severe gingival inflammation. Pregnant or lactating women were excluded from participation
Patients were randomised in blocks of 6 to either the test group or the control group and a total of 111 teeth (test group n=58; control group n=53) were treated. All treated teeth did not have cavities and/or dental fillings at smooth surface sites
For the test group; the BIMIN consisted of an alkaline pretreatment solution (of pH 9) and gelatine film/gel which was used to increase the attractiveness of the tooth surface for mineralisation leading to greater thickness of the mineralised layer. An individualised splint was constructed to prevent saliva flowing under the splint and dissolving the gels. Patients were advised not to eat or drink anything other than water and instructed to wear the splint overnight for a minimum of 8 h. The splint was removed the next morning. The application procedure was defined as successful when the gel was still visible inside the splint
DS was then provoked via a sensitivity assessment using an air stimulation test which was recorded on a VAS with air temperature and pressure between 19 and 24 °C and 40 p.s.i., respectively. Following stimulation, patients were asked to place a vertical mark on a 100mm line to indicate how intense their sensitivity or discomfort felt during the sensitivity test. The anchors of the VAS were labeled “no pain at all” (0 mm) and “unbearable pain” (100 mm). Sensitivity of the treated teeth was assessed before treatment (baseline), and 2 days, 4, 8 and 12 weeks, and 12 months after the single product application
A 2-sided t-test was used alongside Fisher’s Exact Test to statistically analyse the data obtained. VAS value (in mm) was the primary outcome variable of the study
Results:
Scanning electron photomicrographs of untreated and treated teeth illustrated the effect of a single BIMIN application (test group) and control group on exposed dentin
After a single overnight application of BIMIN, the dentin tubules were completely covered with a mineral-like layer (B). This layer was also present after 3 months (C) or 12 months (D). Signs of abrasion, most likely due to oral hygiene procedures, are observed. See figure 1 below.
Conclusion:
The present study demonstrates that biomimetic mineralisation, which mimics natural enamel and dentin formation through controlled ion crystallization, can successfully produce an enamel-like fluorapatite layer on tooth surfaces under in vivo conditions. This process not only supports functional remineralisation but also effectively reduces DS, achieving results comparable to those of established desensitising agent such as those used in the control group. While agents used in the control group offer effective short-term tubule occlusion, its effects diminish over time, whereas the biomimetic system shows potential for longer-lasting structural benefits. The findings suggest that biomimetic mineralisation could provide a promising, biologically inspired approach for managing tooth sensitivity and promoting enamel repair. However, current limitations such as the need for overnight application and use of oral splints should be addressed, and further studies with multiple applications are required to optimise its clinical efficacy and explore its role in preventive and restorative dentistry
Research Summary Written By: Zahra Rushnaiwala, University of Manchester – BDS 2