Teeth talk: time to drill down into dental developments
Finding better ways to keep them
It has been two years since my last dental newsletter — time for more advances to the practice to be known.
To get all up to speed, here is my post from April 2021:
Flouride Free Toothpaste
Exposure to flouride ion is of more and more concern these days, especially for kids. There is a strong push to remove it from oral care products. But what can we use instead to prevent caries and remineralize dentin?
Acid can dissolve hydroxyapatite, leaching it from the tooth structure. Toothpastes containing micro- or nanocrystalline hydroxyapatite particles can restore demineralized enamel surfaces. They are currently being tested as fluoride-free anti-caries agents.
A recent report from Poland describes a clinical trial of one such product:
Background: Dental caries is a worldwide challenge for public health. The aim of this 18-month double-blinded, randomized, clinical trial was to compare the caries-preventing effect of a fluoride-free, hydroxyapatite toothpaste (test) and a toothpaste with sodium fluoride (1450 ppm fluoride; positive control) in adults.
Methods: The primary endpoint was the percentage of subjects showing no increase in overall Decayed Missing Filled Surfaces (DMFS) index. The study was designed as non-inferiority trial. Non-inferiority was claimed if the upper limit of the exact one-sided 95% confidence interval for the difference of the primary endpoint DMFS between test and control toothpaste was less than the predefined margin of non-inferiority (Δ ≤ 20%).
Results: In total, 189 adults were included in the intention-to-treat (ITT) analysis; 171 subjects finished the study per protocol (PP). According to the PP analysis, no increase in DMFS index was observed in 89.3% of subjects of the hydroxyapatite group and 87.4% of the subjects of the fluoride group. The hydroxyapatite toothpaste was not statistically inferior to a fluoride toothpaste with regard to the primary endpoint.
Conclusion: Hydroxyapatite was proven to be a safe and efficient anticaries agent in oral care. - E Paszynska, et al.
This type of fluoride-free toothpaste is on the market shelves. Look for it.
Lozenges to treat dentin hypersensitivity
Exposure of tubular dentin due to the loss of protective mineralized tissues, e.g., enamel at the crown and cementum on the root of the tooth, is a leading cause of tooth hypersensitivity. Fluid movement within the exposed dentin tubules caused by external stimuli, produces pressure fluctuations across dentin, stretching or compressing the nerves located at the pulp, resulting in pain.
The painful sensation emerges when acids wear down tooth enamel. Frequent use of peroxide-based dental whitening products exacerbates this problem. That demineralization exposes the pathways connecting the tooth's hard exterior with its softer interior - dentin and pulp. Pain ensues.
The body can not repair or regrow worn out enamel. To reverse that loss, researchers designed a solution using molecularly biomimetic amelogenin-derived 15−25 amino acid long peptides (ADPs), that facilitate the control of mineralization on human enamel and root dentin.
ABSTRACT. Exposure of dentin tubules due to loss of protective enamel (crown) and cementum (root) tissues as a result of erosion, mechanical wear, gingival recession, etc. has been the leading causes of dentin hypersensitivity. Despite being a widespread ailment, no permanent solution exists to address this oral condition. Current treatments are designed to alleviate the pain by either using desensitizers or blocking dentin tubules by deposition of minerals or solid precipitates, which often have short-lived effects. Reproducing an integrated mineral layer that occludes exposed dentin with concomitant peritubular mineralization is essential to reestablish the structural and mechanical integrity of the tooth with long-term durability. Here, we describe a biomimetic treatment that promotes dentin repair using a mineralization-directing peptide, sADP5, derived from amelogenin. The occlusion was achieved through a layer-by-layer peptide-guided remineralization process that forms an infiltrating mineral layer on dentin. The structure, composition, and nanomechanical properties of the remineralized dentin were analyzed by cross-sectional scanning electron microscopy imaging, energy dispersive X-ray spectroscopy, and nanomechanical testing. The elemental analysis provided calcium and phosphate compositions that are similar to those in hydroxyapatite. The measured average hardness and reduced elastic modulus values for the mineral layer were significantly higher than those of the demineralized and sound human dentin. The structural integration of the new mineral and underlying dentin was confirmed by thermal aging demonstrating no physical separation. These results suggest that a structurally robust and mechanically durable interface is formed between the interpenetrating mineral layer and underlying dentin that can withstand long-term mechanical and thermal stresses naturally experienced in the oral environment. The peptide-guided remineralization procedure described herein could provide a foundation for the development of highly effective oral care products leading to novel biomimetic treatments for a wide range of demineralization-related ailments and, in particular, offers a potent long-term solution for dentin hypersensitivity. - DT Yucesoy, et al.
Further studies utilized clinically applicable peptide delivery systems, e.g., mineralizing gel or paste. The peptide can be integrated into nearly any type of oral health product. In one proof-concept-trial, participants received a dental lozenge the size of a cough drop, with a core of calcium and phosphate coated in a layer of peptide-infused flavoring. Other peptide-based formulations include mouthwash, dental gels, tooth whiteners, and toothpaste. To assess effect, assays (e.g. pH cycling, dye penetration) to the mineralized layer can characterize its molecular adherence, sealing efficacy, and the chemical durability of the mineral–tooth interface.
Soon… we’ll all be flashing those pearly whites!
REFERENCES
K O'Hagan-Wong, et al. The use of hydroxyapatite toothpaste to prevent dental caries, Odontology (2021). DOI: 10.1007/s10266-021-00675-4
E Paszynska, et al. Caries-preventing effect of a hydroxyapatite- toothpaste in adults: A 18 months double-blinded randomized clinical trial, Frontiers in Public Health (2023). DOI: 10.3389/fpubh.2023.1199728. www.frontiersin.org/articles/1 ... bh.2023.1199728/full
DT Yucesoy, et al. Biomimetic Dentin Repair: Amelogenin-Derived Peptide Guides Occlusion and Peritubular Mineralization of Human Teeth, ACS Biomaterials Science & Engineering (2023). DOI: 10.1021/acsbiomaterials.2c01039
O Redha, et al. Compromised dental cells viability following teeth-whitening exposure, Scientific Reports (2021). DOI: 10.1038/s41598-021-94745-w