Exploring the impact of type II diabetes mellitus on voice quality.

PURPOSE: This cross-sectional study aimed to investigate the potential of voice analysis as a prescreening tool for type II diabetes mellitus (T2DM) by examining the differences in voice recordings between non-diabetic and T2DM participants. METHODS: 60 participants diagnosed as non-diabetic (n = 30) or T2DM (n = 30) were recruited on the basis of specific inclusion and exclusion criteria in Iran between February 2020 and September 2023. Participants were matched according to their year of birth and then placed into six age categories. Using the WhatsApp application, participants recorded the translated versions of speech elicitation tasks. Seven acoustic features [fundamental frequency, jitter, shimmer, harmonic-to-noise ratio (HNR), cepstral peak prominence (CPP), voice onset time (VOT), and formant (F1-F2)] were extracted from each recording and analyzed using Praat software. Data was analyzed with Kolmogorov-Smirnov, two-way ANOVA, post hoc Tukey, binary logistic regression, and student t tests. RESULTS: The comparison between groups showed significant differences in fundamental frequency, jitter, shimmer, CPP, and HNR (p < 0.05), while there were no significant differences in formant and VOT (p > 0.05). Binary logistic regression showed that shimmer was the most significant predictor of the disease group. There was also a significant difference between diabetes status and age, in the case of CPP. CONCLUSIONS: Participants with type II diabetes exhibited significant vocal variations compared to non-diabetic controls.

Mechanical properties of simulated dentin caries treated with metal cations and L-ascorbic acid 2-phosphate.

This pH cycling study aimed to investigate the effects of L-Ascorbic acid 2-phosphate (AA2P) salts of Mg, Zn, Mn, Sr, and Ba on the surface microhardness, compressive strength, diametral tensile strength (DTS), and solubility of root canal dentin. 186 cylindrical dentin specimens from 93 teeth were fortified with optimal concentrations of AA2P salts of Mg (0.18 mM), Zn (5.3 µM), Mn (2.2 × 10-8 M), Sr (1.8 µM), and Ba (1.9 µM). Saline was used as the control group. These dentin specimens underwent a 3-day cycling process simulating dentin caries formation through repeated sequences of demineralization and remineralization. Surface microhardness at 100 and 500 µm depths (n = 10/subgroup), scanning electron microscopy (n = 3/group), compressive strength (n = 10/group), DTS (n = 6/group), and solubility (n = 5/group) tests were performed to analyze the dentin specimens. Data were analyzed using Kolmogorov-Smirnov, one-way ANOVA, and Post Hoc Tukey tests (p < 0.05). The control group had significantly lower microhardness at both depths (p < 0.001), reduced DTS (p = 0.001), decreased compressive strength (p < 0.001), and higher weight loss (p < 0.001) than all other groups. The Sr group had the highest compressive strength and microhardness among all the groups. The microhardness was significantly higher for the 500 µm depth than the 100 µm depth (p < 0.001), but the difference in microhardness between depths across groups was not significant (p = 0.211). All fortifying solutions provided some protection against artificial caries lesions. Therefore, these elements might have penetrated and reinforced the demineralized dentin against acid dissolution.

Effects of Diabetes on Elemental Levels and Nanostructure of Root Canal Dentin.

INTRODUCTION: This study evaluated the effects of diabetes mellitus (DM) on the nanostructure of root canal dentin using high-resolution transmission electron microscopy (HRTEM) and inductively coupled plasma mass spectrometry (ICP-MS). METHODS: Twenty extracted human premolars from diabetic and nondiabetic patients (n = 10 in each group) were decoronated and sectioned horizontally into 40 2-mm-thick dentin discs, with each disc designated for a specific test. ICP-MS was used to determine the different elemental levels of copper, lithium, zinc, selenium, strontium, manganese, and magnesium in diabetic and nondiabetic specimens. HRTEM was used to analyze the shape and quantity of the apatite crystals in diabetic and nondiabetic dentin at the nanostructural level. Statistical analysis was performed using Kolmogorov-Smirnov and Student t test (P < .05). RESULTS: ICP-MS revealed significant differences in trace element concentrations between the diabetic and nondiabetic specimens (P < .05), with lower levels of magnesium, zinc, strontium, lithium, manganese, and selenium (P < .05), and higher levels of copper in diabetic specimens (P < .05). HRTEM revealed that diabetic dentin exhibited a less compact structure with smaller crystallites and significantly more crystals in the 2500 nm2 area (P < .05). CONCLUSION: Diabetic dentin exhibited smaller crystallites and altered elemental levels more than nondiabetic dentin, which could explain the higher root canal treatment failure rate in diabetic patients.

Volume and Power of Expansion of Novel Polyurethane-based Sealers.

INTRODUCTION: Shrinkage and lack of interfacial adaptation between endodontic sealers and root canal walls may jeopardize the root canal treatment outcome. This study aimed to evaluate the volume and power of expansion (and the relationship between the two) of three novel root canal sealers (polyurethane expandable sealer [PES], zeolite + PES [ZPES], and elastomeric polyurethane sealer [EPS]) in comparison with an epoxy-resin based sealer (AH Plus) and a calcium silicate-based sealer (EndoSequence BC). METHODS: This study utilized 36 cylinders (30 plastic graduated cylinders for volume of expansion and 6 steel cylinders for power of expansion) (4 × 10 mm) filled with PES, ZPES, EPS, AH Plus, EndoSequence BC, or water (n = 5/group). The plastic graduated cylinders were inserted inside a customized Linear Swell Meter apparatus to measure the percentage of volumetric expansion. The steel cylinders were placed inside a Linear Swell Meter apparatus mounted onto a universal testing machine to measure the maximum pressure in psi. Specimens were tested for 72 hours for both volume and power of expansion tests. Data were analyzed using Kolmogorov-Smirnov, one-way ANOVA, Post Hoc Tukey, and Pearson correlation tests (P < .05). RESULTS: The volume of expansion of PES, ZPES, and EPS was significantly higher than in AH Plus and EndoSequence BC (P < .05). For the power of expansion, no significant differences were found between the root-filling materials (P > .05). No correlation was seen between the volume and power of expansion (P > .05). CONCLUSION: Although polyurethane-based sealers showed a significantly higher volume of expansion compared to AH Plus and EndoSequence BC, their power of expansion did not increase significantly.

Effects of brushing duration on the efficacy of dental plaque removal: An in vitro study.

INTRODUCTION: This study was performed to evaluate the effects of varying brushing times on the dental plaque-removal efficacy of a power toothbrush to determine the optimal length of time required to brush the teeth. METHODS: A typodont with 32 teeth was divided into four quadrants and further divided into four zones each (two teeth per zone). Using a robotic arm, toothbrushing was performed over eight different brushing times (0, 60, 120, 180, 240, 300, 360, and 420 s) to remove the artificial plaque applied on the labial surface of the teeth in occlusion. Photographs were taken every 60 s from each zone of the typodont. The images obtained were processed using ImageJ software to measure the percentage of remaining plaque. Data were analysed with factorial ANOVA, least squares regression analysis, and post hoc Tukey tests. RESULTS: Plaque removal significantly increased with brushing time across the brushing intervals studied (p < 0.05). Efficient plaque removal was achieved after 240 s of brushing. There was no significant difference in plaque accumulations between the maxillary and mandibular arch (p = 0.19) and the right and left areas after each time interval (p = 0.49). CONCLUSION: Brushing duration is negatively correlated with the remaining plaque for a given toothbrush. Two minutes of brushing is not sufficient for significant plaque removal. Considering the limitations of this in vitro study, clinical studies are needed in order to change brushing recommendations to 240 s.

Scoping review of the relationship between xerostomia and voice quality.

PURPOSE: This scoping review aims to synthesize all of the currently available information on how xerostomia correlates with vocal function and the mechanisms that underpin it. METHODS: Our scoping review used PubMed, Scopus, Embase, and Web of Science databases to review articles published between January 1999 and July 2022 in accordance with the PRISMA-ScR guidelines. In addition to the academic databases, we also conducted a manual search of Google Scholar. Further investigation was conducted on studies that examined the relationship between xerostomia and vocal function. RESULTS: Of the 682 initially identified articles, 21 met our inclusion criteria. Among the included studies, two articles (n = 2) revealed the mechanistic relationship between xerostomia and vocal function. Most studies (n = 12) focused on xerostomia secondary to other underlying conditions or treatments, among which radiotherapy and Sjögren's syndrome were commonly investigated. Seven studies (n = 7) provided details about common vocal parameters measured in studies of xerostomia and the voice. CONCLUSION: The literature currently lacks publications regarding the relationship between xerostomia and vocal function. Most of the studies included in this review were about xerostomia secondary to other conditions or medical treatments. Therefore, the impacts on the voice that were observed were very multifaceted and the role of xerostomia alone in phonation could not be ascertained. Nevertheless, it is clear that dryness in the mouth plays some role in vocal function and further research should focus on clarifying and finding the underlying mechanism behind this relationship by incorporating high-speed imaging and cepstral peak prominence analyses.

Neural network approach to evaluate the physical properties of dentin.

This study intended to evaluate the effects of inorganic trace elements such as magnesium (Mg), strontium (Sr), and zinc (Zn) on root canal dentin using an Artificial Neural Network (ANN). The authors obtained three hundred extracted human premolars from type II diabetic individuals and divided them into three groups according to the solutions used (Mg, Sr, or Zn). The authors subdivided the specimens for each experimental group into five subgroups according to the duration for which the authors soaked the teeth in the solution: 0 (control group), 1, 2, 5, and 10 min (n = 20). The authors then tested the specimens for root fracture resistance (RFR), surface microhardness (SµH), and tubular density (TD). The authors used the data obtained from half of the specimens in each subgroup (10 specimens) for the training of ANN. The authors then used the trained ANN to evaluate the remaining data. The authors analyzed the data by Kolmogorov-Smirnov, one-way ANOVA, post hoc Tukey, and linear regression analysis (P < 0.05). Treatment with Mg, Sr, and Zn significantly increased the values of RFR and SµH (P < 0.05), and decreased the values of TD in dentin specimens (P < 0.05). The authors did not notice any significant differences between evaluations by manual or ANN methods (P > 0.05). The authors concluded that Mg, Sr, and Zn may improve the RFR and SµH, and decrease the TD of root canal dentin in diabetic individuals. ANN may be used as a reliable method to evaluate the physical properties of dentin.

Functional role of inorganic trace elements in dentin apatite tissue-part III: Se, F, Ag, and B.

Dentin hydroxyapatite possesses a unique versatile structure which allows it to undergo ionic substitutions. Trace elements play pivotal roles within the oral cavity, especially in dentin apatite tissue. Therefore, it is critical to explore the role of these elements in dentin apatite structure. The roles of other inorganic elements in dentin apatite were discussed in part I (Mg, Sr, Zn, and Fe) and part II (Cu, Mn, Si, and Li) of these series. In the last part of the review series, the role of selenium, fluorine, silver, and boron in the regulation of dentin apatite structure and function was discussed. We evaluated how these elements affect the overall size, morphology, and crystallinity of dentin apatite crystals. Moreover, we investigated the importance of these elements in regulating the solubility of dentin apatite. An electronic search was performed on the role of these trace elements in dentin apatite from January 2010 to January 2022. The concentration of selenium in teeth has been explored only recently, particularly its incorporation into dentin apatite. Silver nanomaterials inhibit the growth of cariogenic microorganisms as well as arrest the degradation of collagen. Fluorine was found to have important roles in dentin remineralization and dentinal tubule occlusion, making it widely used for hydroxyapatite doping. Boron is critical for mineralized tissues like bone, dentin, and enamel, but its exact role in dentin apatite is unknown. Therefore, understanding the impact of these elements on dentin apatite is potentially transformative, as it may help to fill a significant knowledge gap in teeth mechanics.

Diabetes negatively affects tooth enamel and dentine microhardness: An in-vivo study.

OBJECTIVE: This study was performed to evaluate the effect of type 1 diabetes mellitus (T1DM) on the microhardness of tooth enamel and dentine in mice. DESIGN: Seventy male C57BL/6 J mice were used in this study. Thirty-five mice were rendered diabetic by administration of streptozotocin (STZ), and the remaining animals received citrate buffer (normal/non-diabetic). In each group, specimens were divided into 7 subgroups of 5 mice based on the time points 0, 1, 4, 8, 12, 20, and 28 weeks. The microhardness value (MHV) of the second molars' enamel and root dentine were tested with a Vickers microhardness tester. Five specimens from each subgroup were evaluated for dentinal tubular density by scanning electron microscope (SEM) and color dot map analysis to determine the color intensity of strontium (Sr) and magnesium (Mg) by using ImageJ software. RESULTS: The MHV of enamel was significantly reduced in STZ specimens in time points of 12 weeks (STZ: 274.39 ± 15.42, normal: 291.22 ± 15.28), 20 weeks (STZ: 247.28 ± 19.65, normal: 290.68 ± 11.52), and 28 weeks (STZ: 232.87 ± 15.07, normal: 282.76 ± 10.36) (P < 0.05). When comparing the MHV of dentine in subgroups of the normal group, after 20 weeks (169.1 ± 7.5) and 28 weeks (168.6 ± 7.81), the MHV increased significantly (P < 0.05). However, in the STZ group, a significant reduction of MHV was noticed between 28 weeks (131.69 ± 6.2) specimens with other subgroups (P < 0.05). CONCLUSIONS: T1DM negatively affected enamel and dentine microhardness, and enamel was influenced much more negatively and rapidly compared with dentine in diabetic groups.

Functional role of inorganic trace elements in dentin apatite-Part II: Copper, manganese, silicon, and lithium.

Trace elements are recognized as being essential in dentin and bone apatite. The effects of zinc, strontium, magnesium, and iron were discussed in part I. In part II, we evaluated the functional role of copper, manganese, silicon, and lithium on dentin apatite, with critical effects on morphology, crystallinity, and solubility. An electronic search was performed on the role of these trace elements in dentin apatite from January 2000 to January 2022. The recent aspects of the relationship between four different trace elements and their critical role in the structure and mechanics of dentin were assessed. These findings show that elements play a vital role in the human body, especially in the crystalline structure of dentin apatite. Copper presents immense benefits in dental restorative biomaterials because of its importance in enhancing odontogenesis. The biological role of manganese in dentin apatite is still largely unknown, but it has gained attention for many of its broad physiological functions such as modulating osteoblast proliferation, differentiation, and metabolism in bones. The functional role of silicon in dentin apatite is similarly lacking, but findings reveal its importance in mineralization and collagen formation, making it useful for the field of restorative dentistry. Likewise, lithium was found to have important roles in dentin mineralization as well as in the formation of dentin bridges and tissues. Therefore, there is growing importance in studying the aforementioned elements in the context of dentin apatite.

Functional role of inorganic trace elements in dentin apatite tissue-Part 1: Mg, Sr, Zn, and Fe.

Many essential elements exist in nature with significant influence on dentin and bone apatite tissue. Hydroxyapatite (HAp) is the major inorganic crystalline structure of dentin that provides a site for various physiological functions such as surface layer ion exchange. Decades of apatite research have shown that enamel is a high-substituted crystalline apatite, but recent findings suggest that dentin apatite may play a more important role in regulating ion exchange as well as mineral crystallinity. This article is the first part of a review series on the functional role of inorganic trace elements including magnesium, strontium, zinc, and iron in dentin hydroxyapatite. The morphology, physiology, crystallinity, and solubility of these elements as they get substituted into the HAp lattice are extensively discussed. An electronic search was performed on the role of these elements in dentin apatite from January 2007 to September 2021. The relationship between different elements and their role in the mineral upkeep of dentin apatite was evaluated. Several studies recognized the role of these elements in dentinal apatite composition and its subsequent effects on morphology, crystallinity, and solubility. These elements are of great importance in physiological processes and an essential part of living organisms. Magnesium and strontium stimulate osteoblast activity, while zinc can improve overall bone quality with its antibacterial properties. Iron nanoparticles are also vital in promoting bone tissue growth as they donate or accept electrons in redox reactions. Thus, understanding how these elements impact dentin apatite structure is of great clinical significance.

Scoping review of the relationship between diabetes and voice quality.

AIMS: The objective of this scoping review is to synthesize all of the known information about the relationship between diabetes mellitus and voice quality and to explore its potential applications for new technology. METHODS: We conducted a scoping literature review of articles published between March 2000 and September 2021 using the following databases: PubMed, Web of Science, Scopus, and Embase. Additionally, we did a manual search of Google Scholar. The search strategy abides by the PRISMA-ScR guidelines. Studies pertaining to the relationship between diabetes and the voice were categorized separately for further evaluation. RESULTS: Out of the 2732 originally identified articles, nine were ultimately included in this scoping review. The chosen articles address both diabetes and its impact on a variety of vocal parameters. CONCLUSIONS: There is currently very little research investigating the relationship between diabetes, neuropathy, and phonatory symptoms. Additionally, existing publications contain some contradictory findings. Further research that incorporates imaging technology is needed to clarify the physiological explanations for the differences observed between healthy individuals and those with diabetes mellitus. Such information can be used to develop noninvasive technology for diabetes diagnosis and monitoring.

Scoping review of artificial intelligence and immersive digital tools in dental education.

PURPOSE: The aim of this scoping review is to examine artificial intelligence (AI) and virtual teaching models within the context of dental education, establish methods to address the resources being investigated, and ultimately augment this approach for future scientific research. METHODS: To evaluate the applications of AI and immersive technology, a scoping literature review was conducted using the Embase, PubMed, Web of Science, and Cochrane Library database from the years 2018 to May 19, 2021. Additionally, a manual search was completed. The search strategy was formulated according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) guidelines. Studies that addressed the current uses of virtual devices and their revolutionary potential in dental education were categorized separately for further evaluation. RESULTS:  Of the 2500 articles found in our initial search results, 31 articles met the inclusion criteria set for this review. The selected studies were directly related to AI and immersive tools in dental education. CONCLUSION: To our knowledge, there are very few comprehensive literature reviews identifying the applications and efficacy of virtual and AI-driven tools in dental education. With limited verifiable evidence, an improved understanding of virtual and AI domains is needed to enable dental students to adapt to changes within and beyond their dental training education. To increase the scientific value of digital-related research, the scientific community must quickly define guidelines to enhance methodological approaches in order to effectively digitalize dentistry.