Evaluate Efficacy of Desensitizing Toothpaste Containing Zinc-carbonate Hydroxyapatite Nanocrystals: Non-comparative Eight-week Clinical Study

Enhancement of stability and activity of zinc carbonate nanoparticles using chitosan, hydroxyethyl cellulose, methyl cellulose and hyaluronic acid for multifaceted applications in medicine

Currently, biopolymer-based Zn-containing nanoforms are of great interest for medical applications. However, there is lack information on optimal synthesis parameters, reagents and stabilizing agent for production of zinc carbonate nanoparticles (ZnC-NPs). In this work, synthesis of ZnC-NPs was carried out by chemical precipitation with the use of chitosan, hydroxyethyl cellulose, methyl cellulose and hyaluronic acid as stabilizing agents. The optimal precursor (Zn(CH3COO)2) and the optimal precipitator ((NH₄)₂CO₃) were detected. ZnC-NPs had one phase (Zn5(OH)6(CO3)2) with diameter from 35 to 120 nm. Thus, the optimal synthesis parameters were set as stoichiometric ratio of precursor and precipitator and the maximum concentration of biopolymer. It was found that polymers are sorbed on different crystallographic planes of crystallites, which affects the morphology of Zn5(OH)6(CO3). Quantum chemical modelling revealed that all models of interaction are energetically advantageous (∆E > 9788.910 kcal/mol) and preferably occurs through OH group, which was confirmed by FTIR spectroscopy of synthesized samples. Notably, CAM assay and histological evaluation showed that ZnC-NPs stabilized with chitosan (as represent of considered biopolymers) have no toxic effect and are compatible with CAM biological environment, which open a great potential for further studies of ZnC-NPs stabilized with biopolymers for multifaceted applications in medicine.

Dental Applications of Ion-Substituted Hydroxyapatite: A Review of the Literature

Hydroxyapatite (HA) forms an essential constituent of human teeth and bone. Its distinctive characteristic features, such as bioactivity and osteoconductivity, make it an ideal candidate to be used as an implant coating in restorative dentistry and maxillofacial surgery for bone regeneration. However, low fracture toughness and brittleness are a few of the inherent features of HA, which limit its application in load-bearing areas. The potential of HA to engage its lattice structure with either partial or complete substitution with external ions has become an increasing area of research as this phenomenon has the potential to enhance the biological and functional properties of the material. Consequently, this review aimed to highlight the role of various substituted ions in dental applications. Data indicate that the newly formed HA-substituted biomaterials demonstrate enhanced remineralization and antimicrobial activity along with improved hardness. Ion-substituted HA offers a promising strategy for future clinical research as these materials may be incorporated into various dental products for therapeutic treatments.

The Effect of Oral Care Foams and a Spray on Salivary pH Changes after Exposure to Acidic Beverages in Young Adults

Soft drinks may have a deleterious effect on dental health due to a high titratable acidity and a low pH that could be sufficient to induce tooth demineralization. The use of oral care products immediately after acidic challenge may diminish the erosive potential of soft drinks. We assessed the effect of oral care foams and a spray on salivary pH changes after exposure to Coca-Cola® in young adults. Thirty-three consenting eligible patients were recruited in this double-blind, randomized, crossover study performed in six visits. Baseline examination included unstimulated salivary flow rate, stimulated salivary buffer capacity, and the simplified oral hygiene index (OHI-S) assessment. Salivary pH and time for pH recovery were registered after exposure to Coca-Cola® alone or that followed by the application of each of the studied products (an oral foam containing hydroxyapatite and probiotics, an oral foam containing amino fluoride, an alkaline oral spray, and tap water). Thirty-two patients completed the entire study protocol and were included in the final analysis. The mean minimum salivary pH and the mean oral clearance rate after rinsing with Coca-Cola® were 6.3 and 27 min, respectively. Further rinsing with any one of the tested solutions, including tap water, resulted in a significant improvement in these parameters. When the pH curves were plotted, the oral care products demonstrated a lower area under the curve that differed significantly from the area under the curve for Coca-Cola®; tap water did not differ significantly from Coca-Cola® and oral care products. Minimum salivary pH correlated positively with salivary buffer capacity and salivation rate, while salivary clearance correlated with OHI-S plaque scores. In conclusion, the effect of oral care foams and a spray on minimum salivary pH and salivary clearance after exposure to Coca-Cola® did not differ significantly among the tested products and tap water. Trial registration NCT06148662. Funding: none.

Evaluation of remineralizing effect of zinc-carbonate hydroxyapatite on the reduction of postrestorative sensitivity: A randomized controlled clinical trial

Background

The adhesive bonding ability of composite resins makes it unnecessary to remove tooth structure for retention, prevention, and convenience. However, postoperative sensitivity after placing composite restoration has been a significant problem experienced by clinicians.

Aim

The present randomized controlled trial was conducted to assess the role of dentin remineralization in the reduction of postoperative sensitivity after composite placement.

Materials and Methods

Eighty participants with occlusal carious teeth were randomly allocated to one of the four study groups, each having 20 participants, and are as follows: Group A with test group, Group A with control group, Group B with test group, and Group B with control group. Postoperative sensitivity was assessed using the Visual Analog Scale (VAS) and the United States Public Health Service (USPHS) criteria at different time intervals such as baseline, 1 week, 1 month, and 3 months. Data were analyzed using the Kruskal-Wallis ANOVA test, Mann-Whitney U-test, and Wilcoxon matched-pair test.

Results

All 80 participants were analyzed at the baseline, 1 week, 1 month, and the end of 3 months for the postoperative sensitivity using the VAS score and USPHS criteria. One restoration in Group A with control group reported mild sensitivity at the end of 1 week and one restoration in Group B with control group reported severe sensitivity at the end of 3 months, necessitating its replacement followed by root canal treatment. No relationship was reported between postoperative sensitivity and tooth type. There was no statistically significant difference in postoperative sensitivity in any of the treatment modalities.

Conclusion

Class I restoration using self-etch or selective-etch as well as with or without zinc-carbonate hydroxyapatite is a viable and predictable solution for the reduction of postoperative sensitivity if all the aspects of restorative techniques are considered precisely.

The Decision Tree for Clinical Management of Dentin Hypersensitivity. A Consensus Report

PURPOSE

To reach a consensus on a consistent strategy to adopt when screening patients for the clinical management of dentin hypersensitivity.

MATERIALS AND METHODS

A panel consisting of members of the Advanced Technology in Oral Hygiene Sciences Academy (ATASIO) was formed to start a review process on dentin hypersensitivity (DH) and subsequently elaborate a decision tree to manage DH, from diagnosis to prognosis. The panel employed the RAND in their deliberations. After an initial systematic literature review, it became evident that a consensually validated protocol for the management of patients affected by dentin hypersensitivity has to be considered mandatory by all dental professionals. However, the outcome of the systematic review made it evident that the treatment options to be provided, as well as their prognosis and timing, had never been defined. The panel produced documents that addressed the topic and were subsequently used to generate a questionnaire. A workshop of expert dental professionals was organised to reach consensus on the main steps of the decision tree. Each member completed the questionnaire independently, and then a panel discussion was held to reach a consensus.

RESULTS

A high level of agreement was reached regarding all the items on the questionnaire, and each of the clinical questions formulated was answered. A clinical decision threshold was created.

CONCLUSIONS

The dissemination of the information to a wide dental audience should commence upon publication of this consensus document. The authors hope that this consensus will become a model for the development of a dedicated protocol to manage DH.

Hydroxyapatite in Oral Care Products-A Review

Calcium phosphate compounds form the inorganic phases of our mineralised tissues such as bone and teeth, playing an important role in hard tissue engineering and regenerative medicine. In dentistry and oral care products, hydroxyapatite (HA) is a stable and biocompatible calcium phosphate with low solubility being used for various applications such as tooth remineralisation, reduction of tooth sensitivity, oral biofilm control, and tooth whitening. Clinical data on these products is limited with varied results; additionally, the effectiveness of these apatite compounds versus fluoride, which has conventionally been used in toothpaste, has not been established. Therefore, this review critically evaluates current research on HA oral care, and discusses the role and mechanism of HA in remineralisation of both enamel and dentine and for suppressing dentine sensitivity. Furthermore, we position HA’s role in biofilm management and highlight the role of HA in dental applications by summarising the recent achievement and providing an overview of commercialised HA dental products. The review also indicates the existing limitations and provides direction for future research and commercialisation of apatite-based oral care products.

Qualitative and Quantitative Assessment of Remineralizing Effect of Prophylactic Toothpaste Promoting Brushite Formation: A Randomized Clinical Trial

BACKGROUND

Currently various studies are conducted to improve the effect of existing and developing new remineralizing agents. One of the trends in remineralizing therapy is the development of toothpaste allowing brushite crystals formation in the demineralized lesions of hard tooth tissues.

AIM

The aim of this study was to assess the effect of toothpaste, forming a brushite, on the functional acid resistance of enamel and the speed of its remineralization.

MATERIALS AND METHODS

This was a randomized controlled double-blind clinical study. Sixty consent patients aged 20-25 years were enrolled in the three groups: test group (n = 20), positive control group (n = 20), and negative control group (n = 20), which used brushite-forming toothpaste, toothpaste with hydroxyapatite (HAP), and toothpaste without remineralizing agents, respectively. The hygiene indices, the rate of enamel remineralization, the dynamics of acid resistance of enamel, and the level of enamel sensitivity were determined at baseline, after 2 and 4 weeks to assess the effectiveness of toothpastes. Friedman rank sum test (for related variables) and the Kruskal-Wallis rank sum test (for independent variables) with Nemenyi post hoc test were used for statistical comparisons.

RESULTS

The study test and positive control groups showed significantly greater acid resistance of enamel (P > 0.05) and rate of its remineralization at the study endpoints as compared with negative control group.In the test and positive control groups, Schiff index values significantly decreased after 4 weeks, whereas in the negative control group no significant differences were observed at the study time points. The oral hygiene level improved significantly after 2 and 4 weeks in all groups.

CONCLUSION

The 30-day use of paste that promotes brushite formation and paste with hydroxyapatite resulted in faster enamel remineralization and higher enamel resistance. Brushite-containing toothpaste may be used as an alternative to HAP containing for remineralizing and desensitizing treatment.