Enhancing the efficiency of desensitizing agents with shockwave treatment – a new paradigm in dentinal hypersensitivity management

Shockwave application enhances the effect of dentin desensitizer

OBJECTIVES

The purpose of this study was to develop a new device that can improve the effect of desensitizer using shockwaves and to verify its efficacy.

METHODS

A micro-shockwave generator was developed using a piezoelectric actuator (PIA-1000, piezosystem jena GmbH, Jena, Germany), an Arduino Uno microcontroller (Arduino, Torino, Italy), and a high voltage pulser (HVP-1000, piezosystem jena GmbH) at 700 V (400 A) and 100 μs. The occlusal surfaces of 20 extracted human upper and lower third molars without caries or restoration were reduced to expose the occlusal dentin, and the prepared occlusal surfaces were acid-etched with 32% phosphoric acid to remove the smear layer. The tooth specimens were connected to a fluid flow measurement instrument (nanoFlow, IB SYSTEMS, Seoul, Korea), permeability through dentin via dentinal fluid flow (DFF) was measured for 300 s, and the average DFF rate (Baseline DFF rate) was calculated. A desensitizer (SuperSeal, Phoenix Dental, Fenton, MI, USA) was applied to the acid-etched occlusal dentin surface of 10 randomly selected tooth specimens, left for 10 s, and rubbed with a microbrush for 30 s (Group 1). For the remaining teeth, the desensitizer was applied, and a shockwave (100 μm stroke, 10,000 G) was applied for 10 s (2 shots/s) and rubbed with a microbrush for 30 s (Group 2). After desensitizer application, subsequent DFF was measured for 600 s, and the average DFF rate was calculated (post-application DFF rate). DFF was continuously measured in real-time at 25 ± 0.5 ℃ under a hydrostatic pressure of 25 cm. The percentage reduction in DFF rate after desensitizer application (with or without shockwave) was calculated with respect to baseline DFF rate. Data were analyzed with independent t-test (α = 0.05).

RESULTS

For all tooth specimens, DFF rate decreased after desensitizer application irrespective of the presence of shockwaves. The percentage reduction in DFF rate of SuperSeal with shockwave (Group 2) was 42.8 ± 19.0%, which was significantly higher than the 26.2 ± 13.6% of the SuperSeal only group (Group 1) (p < 0.05).

SIGNIFICANCE

Measurement of DFF change in real-time shows that shockwaves can help reduce dentin permeability beyond that SuperSeal dentin desensitizer produced alone.

An in vitro analysis of the effect of adjunctive use of ozonated oil with a desensitizing agent on dentinal tubule occlusion

Introduction

Dentinal hypersensitivity (DH), is a commonly encountered clinical problem, the management of which is by two main approaches that involve blockage of nerve activity and tubular occlusion. Desensitizing agents containing arginine and calcium carbonate have emerged effective in occluding tubules. Ozone removes the smear layer and opens up the dentinal tubules for easy penetration of these desensitizing agents.

Objective

To comparatively evaluate the effect of ozonated oil on the patency and occlusion of dentinal tubules with and without adjunctive application of a desensitizing agent containing arginine.

Materials and methods

80 dentin specimens that were distributed into 4 groups as Group 1 (control), Group 2 (ozonated oil), Group 3 (desensitizing agent) and Group 4 (desensitizing agent following the application of ozonated oil), underwent an acid challenge. Scanning electron microscopic (SEM) images of the dentin specimens were obtained prior to any treatment, after the application of the therapeutic agents and after acid challenge and mean tubule occlusion scores were recorded in each case employing a suitable scoring system. The statistical analysis employed One-way ANOVA test followed by Tukey's Post hoc test and Student Paired t-test for intergroup and intragroup comparisons of the mean tubule occlusion scores respectively.

Results

Group 2, treated with ozonated oil alone showed a statistically significant increase in the number of open dentinal tubules. Group 4 showed more compact deposits of desensitizing agent and more densely occluded tubules as compared to Group 3 which was more retained in the former even after acid challenge.

Conclusion

Adjunctive application of the desensitizing agent containing arginine, with ozonated oil has a synergistic effect, where the latter causes opening of dentinal tubules allowing more compact penetration of the former and thus may be a potentially more effective treatment approach in the management of DH.

Tooth desensitizing calcium phosphate composite gelatin-based gel

Dentine sensitivity is a dental problem common in individuals aged between 20 and 50 years. The most effective treatment method involves occluding the exposed dental tubules. This study focused on the synthesis of calcium phosphate nanoparticles in the form of gel to use as a proof of concept for home-treatment of sensitive teeth. In this study, calcium phosphate nanoparticles were prepared using emulsion method, in which oleic fatty acid was employed as an external phase, and sodium dodecyl sulphate (SDS) was used as a surfactant to form water-in-oil nanodroplets. Finally, in order to facilitate gel formation, the gelatin solution was introduced at the final step. The amount of gelatin varied from 5 to 15 percent by weight, which was found to have an effect on the gels’ properties and the size of calcium phosphate nanoparticles embedded in gel. Based on the characterization, the calcium phosphate nanoparticles were spherical in shape, though the size decreased as the amount of gelatin increased. The gel embedding smallest nanoparticle, that is, gel-15%G, was successfully proven to be non-toxic and able to fully occlude the dentine tubules only after overnight application. According to acid challenge, the occluded materials can resist to acid solution via redissolvation and reprecipitaion process.

Shockwave Therapy Efficiently Cures Multispecies Chronic Periodontitis in a Humanized Rat Model

Biofilms are ubiquitous in nature and are invariably associated with health and diseases of all living beings. Periodontal diseases & dental caries are the most prevalent conditions in which biofilm has established as a primary causative factor. Managing poly-microbial biofilm is the mainstay of periodontal therapy. Plethora of antimicrobials have been used till date to combat biofilm, but the emergence of antibiotic tolerance and resistance in biofilms is a major cause of concern. Apart from use of antimicrobials, various anti-biofilm strategies have evolved which include the use of mechanical, and chemical means to disrupt biofilms. However, none of these approaches have led to desired or optimal biofilm control and hence search for novel approach continues. Shockwaves are used in medical practice for various therapeutic purposes and in local drug delivery, gene therapy, wound healing & regeneration. With this background, a study was designed with an attempt to explore the possibility of using the shockwave for their effect on multispecies oral biofilm development from subgingival plaque samples obtained from chronic periodontitis patients. Plaque samples from 25 patients were used to derive multispecies biofilm which were used to check the efficacy of shockwaves and antibacterial efficacy of four clinically relevant antimicrobials. Biofilms were analyzed by scanning electron microscope; atomic force microscope and their biomass was quantitated by crystal violet staining. Further, a humanized rat model of periodontitis was developed. Patient derived plaque was used to establish periodontitis in healthy rats. The model was validated by performing colony forming unit (CFU) analysis of the infected tissue. The animals were subjected to low intensity shockwaves using a hand-held shockwave generator at the site of infection. Shockwave treatment was done with or without antimicrobial application. The animals were monitored for clearance of infection and for mortality. The results show that shockwave treatment in combination with antimicrobials is significantly effective in clearing a multispecies biofilm. This also brings out the possibility of application of shockwaves in the management of oral biofilms either alone or in combination with established antimicrobial agents. With further research, safety profile validation and clinical trials, shockwaves can be an effective, novel approach in management of biofilm associated periodontal disease.

Potential Novel Strategies for the Treatment of Dental Pulp-Derived Pain: Pharmacological Approaches and Beyond

The diagnosis and management of pain is an everyday occurrence in dentistry, and its effective control is essential to ensure the wellbeing of patients. Most tooth-associated pain originates from the dental pulp, a highly vascularized and innervated tissue, which is encased within mineralized dentin. It plays a crucial role in the sensing of stimuli from the local environment, such as infections (i.e. dental caries) and traumatic injury, leading to a local inflammatory response and subsequently to an increase in intra-pulp pressure, activating nerve endings. However, thermal, chemical, and mechanical stimuli also have the ability to generate dental pulp pain, which presents mechanisms highly specific to this tissue and which have to be considered in pain management. Traditionally, the management of dental pulp pain has mostly been pharmacological, using non-steroidal anti-inflammatory drugs (NSAIDs) and opioids, or restorative (i.e. removal of dental caries), or a combination of both. Both research areas continuously present novel and creative approaches. This includes the modulation of thermo-sensitive transient receptor potential cation channels (TRP) by newly designed drugs in pharmacological research, as well as the use of novel biomaterials, stem cells, exosomes and physical stimulation to obtain pulp regeneration in regenerative medicine. Therefore, the aim of this review is to present an up-to-date account of causes underlying dental pain, novel treatments involving the control of pain and inflammation and the induction of pulp regeneration, as well as insights in pain in dentistry from the physiological, pharmacological, regenerative and clinical perspectives.