Clinical Effectiveness of Powder Jet Deposition for Dentin Hypersensitivity

Objectives: Powder Jet Deposition (PJD) is a technique that forms a new layer of enamel on the tooth surface by colliding fine particle hydroxyapatite (HAP), the main component of teeth, onto the tooth at high speed using a dental hand-piece under room temperature and atmospheric pressure. It is expected to become a new method of treating caries and dentin hypersensitivity, sealing pits and fissures, and improving color tone, by coating tooth surfaces. In this study, we investigated the clinical effectiveness of HAP layer formation by PJD for relief of dentin hypersensitivity.
Methods: The study was conducted on 20 subjects diagnosed as having dentin hypersensitivity. A HAP layer was formed on the area confirmed to be hypersensitive by applying HAP powder for approximately 30 seconds by PJD. The degree of pain felt in response to air stimulation (15±3L/min) and cold-water stimulation (15°C) before and after treatment and after 2 weeks of treatment was recorded by each subject using a Numerical Rating Scale (NRS). The data obtained were statistically analyzed using the Wilcoxon signed-rank test with Bonferroni correction (P<0.05).
Results: NRS showed a variety of trends ranging from little change to complete disappearance of pain, but overall scores decreased significantly after treatment compared with their level before treatment.
Conclusions: HAP layer formation by PJD was shown to be clinically effective and a potential treatment for dentin hypersensitivity. The various trends shown in this study may be influenced by the angle of application according to tooth morphology and target area. We plan to investigate methods of treatment, including the angle of application for areas where layer formation is difficult, such as subgingival and proximal surfaces.