Dentin Hypersensitivity

Desensitizing efficacy of a universal dentin adhesive containing mesoporous bioactive glass on dentin hypersensitivity: a randomized clinical trial with a split-mouth model

This split-mouth blinded randomized controlled study compared the efficacy of a desensitizing agent with oxalate/resin polymer and a universal adhesive containing mesoporous bioactive glass (MBG) for dentin hypersensitivity (DH) relief, using Schiff sensitivity score (SSS) and visual analog scale (VAS). Split quadrants containing teeth with DH were treated with either MS Coat ONE or Hi-Bond Universal with MBG as the functional additive. Assessments at baseline, immediately post-application, and at 1- and 2-week follow-ups used standardized stimulus protocols (air, cold, and acid). The SSS difference was the primary outcome, while the VAS difference was the secondary outcome. A mixed linear effect model performed statistical analysis. Immediate DH reduction occurred in response to air stimuli, with a significant decrease in Group HB than in Group MS (p = 0.0178). Cold stimulus reduction exhibited a gradual cumulative effect, with consistently greater reductions in Group HB than in Group MS (p ≤ 0.0377). Both groups effectively managed acidic stimuli, with no significant differences (p > 0.05). The VAS scores decreased gradually over the follow-up period (p < 0.0001). This study highlights the differential efficacy of treatments for various DH triggers and recommends specific approaches based on different stimulus types. The universal adhesive containing MBG demonstrated DH relief potential, promising efficacy identical to or superior to that of a dedicated desensitizing agent. Further research exploring the long-term efficacy and underlying mechanisms is warranted. The universal adhesive containing MBG can be adopted as an in-office desensitizing agent for DH relief. The desensitizing efficacy of universal adhesive matches or surpasses dedicated agents for air and cold stimuli.

Efficiency of cavitary varnishes containing experimental bioglass particles in the occlusion of dentinal tubules

This research aims to evaluate the efficiency of cavitary varnishes containing experimental bioglasses in the occlusion of dentinal tubules. One hundred and sixty-eight cervical buccal dentin samples were obtained from bovine teeth. Samples were randomized into the following groups: I. Distilled Water (DW); II. Cavity Varnish (CV); III. Colgate® Sensitive Pro-Relief™ (CS); IV. 45S5 Bioglass (45S5); V. KSr Bioglass strontium potassium (KSr); VI. P Bioglass phosphorus (P); and VII. PSi Bioglass phosphorus silica (PSi). The treatments were applied to the surfaces of the samples, which were then subjected to simulated brushing. The samples were analyzed for a) characterization of bioactive glasses; b) surface roughness; c) descriptive analysis of the dentin surface; d) total versus occluded number of dentinal tubules; e) diameter of the dentinal tubules; f) chemical composition of the dentin surfaces, and g) dentin permeability. All groups treated with biomaterials without the brushing challenge showed an increase in roughness and (total or partial) occlusion of the dentinal tubules. The PSi group had the best values for occlusion, while the KSr group had the highest calcium and phosphorus concentrations. After the brushing challenge the roughness was controlled by the presence of biomaterials; 45S5, KSr, and PSi showed occlusion of the dentin tubules. All bioactive glasses showed reduced tooth permeability compared to distilled water. The PSi group had the smallest tubule diameter and highest phosphorus concentration. KSr and PSi bioglasses are promising materials for dentin occlusion and remineralization and are promising new biomaterials for the treatment of dentin hypersensitivity.

Investigation of the constituents of commercially available toothpastes

OBJECTIVES

Toothpaste plays a pivotal role in oral and dental hygiene. This cross-sectional study not only investigates the constituents of toothpastes available in the market and their frequency across different brands but also delves into the potential side effects, irritations, or unfavourable outcomes of these constituents, emphasizing the broader health and environmental implications.

METHODS

The largest of the five major chain markets in each district of Istanbul was visited, and adult toothpastes were included in this study. All the constituents that make up the toothpaste were individually recorded in an Excel database. Subsequently, literature regarding the purposes, toxic and potential side effects of each ingredient was gathered using databases such as Google Scholar, PubMed and ScienceDirect. The percentages of these ingredients' occurrence among all the toothpastes were calculated, and the ingredients were categorized into 15 distinct groups based on their usage purposes.

RESULTS

There were 160 different varieties of toothpaste belonging to 19 different brands on the market shelves. Although a total of 244 different ingredients were identified, only 78 of them were included in the study. Among the analysed toothpaste types, 105 of them were found to contain 1450 ppm fluoride, whilst 26 toothpaste variants were discovered to have fluoride levels below this value. Among the various ingredients analysed, particular attention was drawn to commonly debated compounds in oral care products. Specifically, titanium dioxide was found in 68% (n = 111) of the varieties, sodium lauryl sulphate in 67% (n = 108) and paraben in 2% (n = 4), respectively.

CONCLUSION

Whilst certain ingredients may raise concerns for potential side effects and health considerations within the human body, the toothpaste has long been regarded as an indispensable tool for maintaining optimal oral and dental health. However, gaining a deeper understanding and conducting research on each constituent that comprises the toothpaste, as well as raising awareness in this regard, holds significant importance for human health.

Dentists' education, knowledge, and professional behavior concerning the diagnosis and treatment of dentin hypersensitivity: An exploration

OBJECTIVES

Dentin hypersensitivity (DH) affects patients' oral health-related quality of life, but is not always optimally treated in dental offices. The objectives were to assess dentists' DH-related education, knowledge, and professional behavior and explore relationships between education, knowledge, and behavior.

METHODS

Survey data were collected from 220 ADA members in the United States. Descriptive and correlational analyses were performed.

RESULTS

About half of the respondents agreed/strongly agreed that their dental school had educated them well about diagnosing DH in classroom-based (53.6%) and clinical settings (48.9%). Lower percentages agreed being well educated about treating DH (40.9%/37.3%). The majority self-educated themselves about DH after dental school by attending continuing education courses in person or online (60.6%/36.8%), reading articles (64.1%), or consulting with colleagues (59.6%). The majority knew that patients with DH describe their pain as stimulated (91.4%) and that recessed gingiva (89.6%), abrasion lesions (72.3%), tooth whitening (63.1%), erosion lesions (58.6%), and abfraction lesions (51.4%) are risk factors for DH. The majority diagnosed DH with patient self-reporting, confirmed by exams (81.8%), applying air blasts (53.7%), or cold-water (52.3%). They treated patients with DH often/very often with over-the-counter desensitizing agents (90%), and prescribing fluoride formulations toothpaste (82.8%) and/or potassium nitrate toothpastes (60.9%). In their offices, the majority (73.2%) educated their patients often/very often about DH and used fluoride dental varnish for treating DH (71.8%). The more recently respondents had graduated from dental school, the more positively they described their dental school education (r = 0.14; p < 0.05), the more ways to diagnose DH they used (r = 0.16; p < 0.05) and the more often they used fluoride dental varnish in their offices (r = 0.23; p < 0.001). The more dentists had educated themselves, the more methods for diagnosing DH they used (r = 0.23; p < 0.001) and the more often they used potassium oxalate products (r = 0.19; p < 0.01), Arginine/calcium products (r = 0.19; p < 0.01) and dentin bonding (r = 0.22; p < 0.001).

CONCLUSIONS

More recently graduating from dental school correlates with more positive evaluations of DH-related dental school education. The finding that most dentists engage in self-education about DH after dental school should motivate dental educators to increase education about this topic not only in dental school, but also in continuing education courses.

Efficacy of Different Fluoride Therapies on Hypersensitive Carious Lesions in Primary Teeth

Background and Objectives: This prospective, comparative, double-cohort study aimed to compare the efficacy of silver diamine fluoride and potassium iodide (38% SDF+KI; Riva Star®) with sodium fluoride varnish (5% NaF; Duraphat®) in hypersensitive carious lesions in primary teeth to evaluate caries arrest and hypersensitivity relief. Materials and Methods: This study included thirty 2-5-year-olds (mean age = 3.67 ± 1.06 years; 16 males and 14 females) who required a desensitizing treatment for hypersensitive carious defects with visible dentin. A total of 15 of the participants were consecutively allocated to treatment with 5% NaF, and they were further compared to an equal number of participants treated with 38% SDF+KI solutions (n = 15). The treatments were performed following clinical evaluation of caries activity using the International Caries Classification and Management System (ICCMSTM) and the Bjørndal criteria (score of 0-9). Parental-reported hypersensitivity was evaluated using a visual analogue scale (0-10 = no to severe pain). Results: Clinical variables were evaluated at baseline and three months after treatment. Thereafter, a significant decline in hypersensitivity/pain led to lower final scores in the Riva Star® group (0.40 ± 1.12, p = 0.002) than in the Duraphat® group (1.40 ± 2.20, p = 0.004). The caries arrest effect was significantly higher in the Riva Star® group (86.7%) compared to the Duraphat® group three months after treatment (13.3%, p < 0.001). In both groups, there were no statistically significant differences in the children's behavior before, during, and after treatment. Conclusions: Ultimately, with both fluoride therapies reducing hypersensitivity/pain significantly, treatment with 38% SDF+KI was clearly more effective in caries arrest than 5% NaF varnish after a 3-month period.

Dentinomimetics and cementomimetics of Moringa oleifera leaves extract

To evaluate the biomimetic remineralization capabilities of Moringa oleifera leaves (MOL) extract on coronal dentin and acellular cementum, two different concentrations (50 and 200 mg/ml) of MOL extract loaded in plain varnish (M1 and M2 groups respectively) were compared to fluoride varnish (FL group) and native surface (C group). Eighty sound premolar teeth were collected. Forty teeth (10 teeth in each group) were used for coronal dentin testing while the other forty (10 teeth in each group) were used for acellular cementum testing. Teeth in M1, M2, and FL groups were etched for 30 s and then received the specific varnish treatment. All samples were immersed in artificial saliva for 14 days and then collected, dried, and examined by scanning electron microscopy and energy dispersive X-ray spectroscopy (EDX). Histologically, FL group showed mineral deposition as discrete vesicular granules of various sizes on the surface of both coronal dentin and acellular cementum. Mineral deposition only occurred on some DTs openings while opened tubules remained. The surface of the acellular cementum revealed regular grooves, micro-fissures, and cracks. In the M1 and M2 groups, mineral deposition appeared as a homogenous continuous layer on coronal dentin and acellular cementum. Only a few DTs and cementum fissures were not filled completely. In L.S. sections of the coronal one-third, the DTs appeared almost sealed with varying lengths of mineral deposition. EDX results statistical analysis showed that the M2 group had the highest phosphate ions (P-) and calcium ions (Ca+2) at%. MOL has an extraordinary effect on the remineralization of coronal dentin and acellular cementum. It would have a promising ability to control dentinal hypersensitivity and formation of biomimetic cementum tissue.

The Effects of a Novel Nanohydroxyapatite Gel and Er: YAG Laser Treatment on Dentin Hypersensitivity

PURPOSE

This study evaluates the effects of a novel nanohydroxyapatite gel and Er: YAG laser on the surface roughness, surface morphology, and elemental content after dentin hypersensitivity treatments.

METHODS

Dentin discs (2 × 3 × 3 mm3) were prepared from 75 human molars. Out of 75 human molars, 50 were used to evaluate surface roughness and randomly divided into five groups: Group ID (intact dentin), Group DD (demineralized dentin), Group BF (fluoride varnish/Bifluorid 10), Group Lsr (Er: YAG laser-50 mJ, 0.50 W, 10 Hz), and Group NHA (nanohydroxyapatite-containing gel). Dentin hypersensitivity was stimulated by 35% phosphoric acid for 1 min (except Group ID). The surface roughness (Ra, μm) was measured via contact profilometry (n = 10). Out of the 75 sound human molars, 25 were used to evaluate the surface morphology and elemental content using scanning electron microscopy and energy-dispersive X-ray spectroscopy (n = 5). The data were statistically analyzed using Welsch ANOVA, Games-Howell, Kruskal-Wallis, and Dunn tests (p < 0.05).

RESULTS

Group Lsr showed significantly lower surface roughness than Group NHA and Group BF (p < 0.05). The SEM analysis indicated that most of the dentinal tubules were obliterated for Group NHA. Precipitant plugs with partially occluded dentinal tubules were observed for Group BF, while partially or completely occluded tubules with a melting appearance were detected for Group Lsr. The EDS analysis revealed that Group NHA and Group Lsr presented similar calcium and phosphorus amounts to Group ID. All dentin hypersensitivity treatment methods could provide promising results in terms of tubular occlusion efficiency. However, laser treatment resulted in smoother surfaces, which could help prevent dental plaque accumulation.

Evaluation of Bioactive Glass Treatment for Dentin Hypersensitivity: A Systematic Review

The aim of this systematic review is to compare home and office desensitizers containing bioactive glass with control groups in randomized controlled trials (RCT) conducted between 2018 and 2022. According to PRISMA guidelines, three electronic databases (Scopus, PubMed, and Cochrane Library) were searched for published scientific articles in October 2022. RCT with adult participants with dentin hypersensitivity (DH) diagnosed by evaporative, mechanical, or thermal stimulation, with a follow-up period and quantified pain assessment were included in the study. Studies that reported DH due to tooth restoration, crown preparation, bleaching, or periodontal surgery or used bioactive glass-ceramics were excluded. The quality of the studies was assessed using version 2 of the Cochrane Risk-of-Bias Tool for randomized studies (RoB 2 tool). Articles that were duplicative or unrelated to this study were excluded. Nine articles were selected for full-text evaluation, whereas two articles were rejected. The remaining seven reports were included in this review. The calcium sodium phosphosilicate group (CSPS) was not significantly different from the positive control groups. Compared with the control groups, fluoro calcium phosphosilicate (FCPS) may be the most effective long-term treatment option. In terms of DH symptom reduction, the FCPS group performed better than the CSPS group. CSPS at a concentration of 5-15% and FCPS at a concentration of 5% are effective in treating DH in adult participants.

The Effectiveness of Calcium Phosphates in the Treatment of Dentinal Hypersensitivity: A Systematic Review

Dentin hypersensitivity (DH) pain is a persistent clinical problem, which is a common condition known to affect patients' quality of life (QoL), but no treatment has ever been agreed upon. Calcium phosphates, available in different forms, have properties that allow sealing the dentinal tubules, which may relieve dentin hypersensitivity. The aim of this systematic review is to evaluate the ability of different formulations of calcium phosphate to reduce dentin hypersensitivity pain level in clinical studies. The inclusion criterion was as follows: clinical randomized controlled studies using calcium phosphates in treating dentin hypersensitivity. In December 2022, three electronic databases (Pubmed, Cochrane and Embase) were searched. The search strategy was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The bias assessment risks results were carried out using the Cochrane Collaboration tool. A total of 20 articles were included and analyzed in this systematic review. The results show that calcium phosphates have properties that reduce DH-associated pain. Data compilation showed a statistically significant difference in DH pain level between T0 and 4 weeks. This VAS level reduction is estimated at about -2.5 compared to the initial level. The biomimetic and non-toxic characteristics of these materials make them a major asset in treating dentin hypersensitivity.

Clinical Efficacy of Mouthwashes with Potassium Salts in the Treatment of Dentinal Hypersensitivity: A Systematic Review and Meta-analysis

AIM

This systematic review and meta-analysis evaluated whether the home use of mouthwashes containing potassium salts is effective in reducing and controlling dentin hypersensitivity (DH).

METHODS AND MATERIALS

This study is reported according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) checklist and was registered in PROSPERO (CRD42021228410). Randomized clinical trials evaluating the use of mouthwashes containing potassium salt for daily household mouthwash for at least four weeks to reduce DH compared with a control mouthwash were selected, with no limitation on year of publication. Electronic research was carried out in PubMed/MEDLINE, Scopus, Web of Science, and Cochrane Library by two independent researchers. One hundred thirty-three articles were obtained, and nine were selected according to the inclusion criteria.

RESULTS

The selected studies evaluated DH through tests of sensitivity to tactile and evaporative stimuli and showed that, for the tactile stimulus, there were no baseline differences between groups (p=0.12; mean difference: -0.33; confidence intervals [CI]: -0.73 to 0.08). However, there were significant differences after two weeks of use (p=0.00001; mean difference: 4.67; CI: 4.53 to 4.81), after four weeks (p=0.00001; mean difference: 13.29; CI: 13.03 to 13.55), and after eight weeks (p=0.00001; mean difference: 8.88; CI: 5.73 to 12.02) favoring the experimental group. The results of the evaporative test showed no differences in the baseline assessment between the two groups (p=0.50; mean difference: -0.02; CI: -0.09 to 0.04), but after four weeks (p=0.00001; mean difference: -0.32; CI: -0.44 to -0.20), and eight weeks of use (p=0.00001; mean difference: -0.42; CI: -0.57 to -0.27) there were differences favoring the experimental group. The incidence of side effects showed no differences between the two groups (p=0.89; mean difference: 1.03; CI: 0.67 to 1.58).

CONCLUSION

The daily use of mouthwashes containing potassium salt is effective in the treatment of dentinal hypersensitivity, as a complementary step to brushing at least twice a day for two weeks, four weeks, and up to eight weeks, without presenting side effects.

Biomineralization-inspired sandwich dentin desensitization strategy based on multifunctional nanocomposite with yolk-shell structure

Dentin hypersensitivity (DH) treatment is far from being unequivocal in providing a superior strategy that combines immediate and long-term efficiency of dentinal tubule (DT) occlusion and clinical applicability. In order to achieve this aim, a type of multifunctional yolk-shell nanocomposite with acid resistance, mechanical resistance and biomineralization properties was developed in this study, which consists of a silica/mesoporous titanium-zirconium nanocarrier (STZ) and poly(allylamine hydrochloride) (PAH)-stabilized amorphous calcium phosphate (ACP) liquid precursor. First, the nanocomposite, named as PSTZ, immediately occluded DTs and demonstrated outstanding acid and mechanical resistance. Second, the PSTZ nanocomposite induced intrafibrillar mineralization of single-layer collagen fibrils and remineralization of demineralized dentin matrix. Finally, PSTZ promoted the odontogenic differentiation of dental pulp stem cells by releasing ACP and silicon ions. The reconstruction of the dentin-mimicking hierarchical structure and the introduction of newly formed minerals in the upper, middle and lower segments of DTs, defined as sandwich-like structures, markedly reduced the permeability and achieved superior long-term sealing effects. The nanocomposite material based on mesoporous yolk-shell carriers and liquid-phase mineralized precursors developed in this study represents a versatile biomimetic sandwich desensitization strategy and offers fresh insight into the clinical management of DH.

Twelve-Month Follow-Up of Different Dentinal Hypersensitivity Treatments by Photobiomodulation Therapy, Nd:YAG and Nd:YAP Lasers

In this retrospective study, data for three different laser-assisted approaches for the management of dentinal hypersensitivity (DH) was collected (n = 920 teeth). In total, 387 teeth were treated with photobiomodulation (PBM) therapy with 660 nm red light laser (PBM group), 327 were treated with the Nd:YAG laser (1064 nm) and 206 were treated with the Nd:YAP laser (1340 nm). To assess the effectiveness of each treatment, a visual analogue scale (VAS) was used, where zero represented no pain at all and ten represented the greatest pain. VAS was used before (T0), immediately after (T1), one week after (T2), four weeks after (T3), six months after (T4) and one year after treatment (T5). Means and standard deviations of VAS at different follow-up times were calculated. Values were compared within and between groups. Statistical significance was considered to be achieved when p-value was less than 0.05. Confidence level was proposed to be 99% with a P value lower than 0.001. Within groups, a statistically significant reduction was obtained when the mean value of VAS at T0 was compared with T5. At T5, the PBM group had the highest reduction of VAS (with mean value of 0), while the Nd:YAG and Nd:YAP groups had scores of 1.065 ± 0.674 and 4.665 ± 0.674, respectively. Conclusion: this retrospective study showed that PBM therapy and irradiation with Nd:YAG and Nd:YAP lasers are effective in managing DH pain. However, PBM therapy was the only procedure that showed complete pain relief at six and twelve months after treatment.

Zwitterionic/phosphonate copolymer coatings endow excellent antifouling properties and robust re-mineralization ability of dentine substrates

Inhibition of biofilm formation and induction of the re-mineralization of damaged dental tissues are two major strategies to combat dental hypersensitivity (DH). However, single component synthetic materials normally cannot fulfil these two functions during the repairing of damaged dental tissues. Here, we report zwitterionic phosphorylcholine based polymers to be a new type of dual functional coating for the repairing of DH. Zwitterionic/phosphonate copolymers, p(DEMMP-co-MPC), bearing varied zwitterionic contents (95 and 75 mol%) were prepared through conventional radical copolymerization. ¹H NMR spectroscopy clearly indicated the precise preparation of the copolymers. The copolymers can be easily coated on dentine substrates based on the high affinity between the phosphonate group and the calcium phosphate minerals of the dentine substrates, as evidenced by XPS and water contact angle measurements. Antifouling evaluations indicated that zwitterionic coating can efficiently inhibit protein adsorption (BSA, egg white, and milk, by 85%) and bacterial adhesion (by 97.1%) on dentine substrates. Furthermore, in vitro and in vivo experiments consistently indicated that the zwitterionic coating could not only induce the robust re-mineralization of dentine surfaces, but also template the extensive re-mineralization of dentine tubules to a similar level of pristine dentine. Both the antifouling properties and the re-mineralization potency are positively correlated with the content of zwitterionic pMPC in the coating copolymer. These findings may provide the zwitterionic phosphorylcholine based materials to be a promising candidate to treat dental hypersensitivity and other related dental diseases.

Is whitening toothpaste safe for dental health?: RDA-PE method

The relative dentin abrasivity-profilometry equivalent values were compared using non-contact profilometry with three subtypes of regular toothpaste and two subtypes of whitening toothpaste containing sodium bicarbonate and 35% hydrogen peroxide. Bovine dentin specimens were assigned to six groups: regular toothpaste (R): R1 (BAMBOO SALT GUM OINTMENT); R2 (MEDIAN TARTAR ORIGINAL); R3 (PERIOE Alpha), Reference slurry: RS (calcium pyrophosphate), whitening toothpaste (W): W1 (NET. WT); W2 (Vussen 28 WHITENING). Relative dentin abrasion-profilometry equivalent (RDA-PE) was determined by brushing 10,000 times (n=8). The pH of the toothpaste was measured (n=5) and the abrasive constituents of the toothpaste was analyzed by FE-SEM and EDS. The RDA-PE values ranged from 26 to166, and the pH level ranges were 4.928-9.153. The RDA-PE value of the whitening toothpaste containing hydrogen peroxide was not high compared with that of the regular toothpaste. The RDA-PE values of whitening toothpaste could vary depending on the mechanism and ingredients of the whitening agents.

Effectiveness of surgical root coverage on dentin hypersensitivity: A systematic review and meta-analysis

AIM

To assess the effect of surgical root coverage (RC) on dentin hypersensitivity (DH) associated with gingival recession.

MATERIALS AND METHODS

Two independent reviewers conducted electronic literature searches in MEDLINE (PubMed), EMBASE, Cochrane Library, Web Of Science, Dentistry & Oral Sciences Source, ScienceDirect, and ClinicalTrials.gov databases as well as a manual search to identify eligible clinical studies from January 2000 to March 2022. Randomized controlled trials (RCTs) comparing two surgical RC techniques or a surgical RC technique with or without adjuvant were included. Meta-analyses were performed on data provided by RCTs.

RESULTS

Thirteen RCTs with a total of 701 patients (1086 recessions) were included. The percentage of DH suppression was 70.8% (95% confidence interval [CI] [64.4-76.6]; I²  = 39.2% [3.5-61.8], Q-test = 0.02) after surgical RC. Recession reduction and percentage of RC were both statistically significantly associated with DH suppression (estimate = 0.66 [0.10-1.23], p = .022, R²  = 14.45% and estimate = 0.04 [0.01-0.08], p = .012, R²  = 29.54%, respectively). Coronally advanced flap (CAF) + connective tissue graft showed results statistically more effective than CAF + xenogeneic collagen matrix in DH suppression (73.3% [65.6-79.8] and 61.4% [51.7-70.3], respectively; p = .048).

CONCLUSIONS

Success of surgical RC is associated with DH suppression.

Formulations of desensitizing toothpastes for dentin hypersensitivity: a scoping review

Objective:

This study aimed to review evidence from randomized controlled trials (RCTs) to describe: 1) the active ingredients and desensitizing toothpaste brands; 2) the evaluation of these active ingredients over time, and 3) the fluoride and abrasive content in the formulations designed to treat dentin hypersensitivity (DH).

Methodology:

In total, 138 RCTs and their tested toothpastes were included. Searches were updated up to August 19, 2021. Formulations, reported brands, active ingredients over time, and type of fluoride (ionizable or ionic fluoride) and abrasive (calcium or silica-based) were analyzed (PROSPERO #CRD42018086815).

Results:

Our trials assessed 368 toothpaste formulations, including 34 placebo (9%), 98 control toothpastes with fluoride (27%), and 236 (64%) with active ingredients to treat DH. We tested the following active ingredients: potassium compounds (n=68, 19%), calcium sodium phosphosilicate (CSP) (n=37, 10%), strontium compounds (n=28, 8%), arginine (n=29, 8%), stannous fluoride (SnF2) (n=21, 6%), hydroxyapatite (n=9, 2%), potassium combined with another active ingredient (n=19, 5%), inorganic salt compounds (n=11, 3%), citrate (n=5, 1%), formaldehyde (n=3, 1%), herbal (n=4, 1%), copolymer (n=1, 0.5%), and trichlorophosphate (TCP) (n=1, 0.5%). The number of toothpaste formulations increased since 1968, with the greatest increment after 2010. Most toothpastes described their type of fluoride as sodium monofluorphosphate (MFP) (n=105, 29%) and NaF (n=82, 22%), with silica-based (n=84, 23%) and calcium-based (n=64, 17%) abrasives.

Conclusion:

Patients and dentists enjoy an increasing number of brands and active ingredients to decide what desensitizing toothpaste to use. The most common types of fluoride are MFP and NaF.

Effectiveness of Two Different Fluoride-Based Agents in the Treatment of Dentin Hypersensitivity: A Prospective Clinical Trial

Hyperesthesia is related to increased sensitivity of dental tissues to mechanical, chemical and thermal stimuli. The aim of this prospective clinical trial was to compare the effectiveness of a calcium-fluoride-forming agent (Tiefenfluorid^®, Humanchemie GmbH, Alfeld, Germany) with that of a fluoride varnish (Enamelast^TM, Ultradent Inc., Cologne, Germany) in the treatment of dental hyperesthesia in adult patients. In total, 176 individuals (106 females and 70 males, aged 18-59 years old) diagnosed with dental hyperesthesia (DH) were enrolled. The main clinical symptoms were hyperesthesia from coldness and sweetness during chewing; the types of clinical lesions were also determined and recorded. The patients were selected randomly and divided into two groups: (i) the first group of 96 patients was treated with Tiefenfluorid^® applied in three appointments at 7-day intervals; (ii) the second group of 80 patients was treated with Enamelast^TM, applied seven times at 7-day intervals. All the patients were recalled 7 days, 14 days, 1 month, 3 months, and 6 months from the last application. At the baseline and during every follow-up visit, the DH was measured with a pulp tester. A random intercept/random slope model was used to evaluate the effect of the treatment, at various times with respect to the initial diagnosis. Within the limits of the present study, Tiefenfluorid^® was more effective than Enamelast^TM against DH in that it provided long-lasting results, with a significant improvement still detected at the latest 6-month follow-up.

Anti-Acid Biomimetic Dentine Remineralization Using Inorganic Silica Stabilized Nanoparticles Distributed Electronspun Nanofibrous Mats

Background

To manage the sharp pain of dentine hypersensitivity, various materials are utilized to conduct dentine remineralization. However, many prior materials are limited with their single function and complicated operations. In this study, silica and calcium (strontium) carbonates mineralized nano cellulose fibrous (Si/Ca(Sr)-NCF) mat with the ability to release acid resistant and biomimetic mineralizational silica/calcium (strontium) carbonate co-precipitation nanoparticles (Si/Ca(Sr) NPs) were fabricated. The dentine occluding effects, antibacterial activity and cytocompatibility of the Si/Ca(Sr)-NCF mats were evaluated.

Methods

The Si/Ca(Sr)-NCF mats were fabricated by dipping the electrospun nano cellulose fiber (NCF) into silica and calcium (strontium) carbonate liquid. Physicochemical characterizations and ion release were confirmed by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), ion release assays and transmission electron microscopy (TEM). Sixty dentine discs were randomly divided into five groups: 1, blank NCF; 2, Si/Ca(Sr 0)-NCF; 3, Si/Ca(Sr 0.01)-NCF; 4, Si/Ca(Sr 0.05)-NCF; 5, Si/Ca(Sr 0.1)-NCF. Dentine discs were mineralized by the mats and observed with SEM immediately, after acid challenge and remineralized in artificial saliva. The releasing liquid was investigated by TEM and type I collagen model. Then, antibacterial property and cytocompatibility were evaluated.

Results

SEM and TEM results confirmed that the experiment mats continuously released amorphous Si/Ca(Sr) NPs and consequently realized anti-acid dentine biomimetic remineralization. Homogeneous surface coverage and collagen intrafibrillar mineralization in strontium adding groups illustrated the mineralization effect was not only by in site precipitation, but also collagen heterogeneous nucleation. Additionally, acceptable antibacterial and cytocompatibility properties were illustrated in low and middle Sr²⁺ containing mats.

Conclusion

In vitro studies on human dentine discs and type I collagen demonstrated that Si/Ca(Sr)–NCF system was a multifunction system inducing anti-acid, biomimetic, antibacterial and cytocompatible dentine remineralization. This multifunction mat would be a promising DH treatment candidate for complicated exposed dentine surfaces.

[An integrated approach to reducing hyperesthesia of teeth in patients with underlying somatic pathology]

THE AIM OF THE STUDY

Was to analyze the effectiveness of therapeutic and preventive measures aimed at reducing hyperesthesia of hard dental tissues in patients with background somatic diseases.

MATERIALS AND METHODS

The study involved 113 patients with increased tooth sensitivity and treated in the gastroenterological and endocrinological departments of the S.M. Kirov City Clinical Hospital No.3» in Astrakhan in the period from 2018 to 2021 at the age of 26-43 years. The main group included 52 patients with confirmed diagnoses of gastric and duodenal ulcer, pancreatitis and type II diabetes mellitus who were treated for dental hyperesthesia with an integrated approach. The control group included 61 patients with periodontal disease without background somatic pathologies in whom hyperesthesia was treated by remineralizing therapy. The effectiveness of the treatment was determined in dynamics on the 10th and 40th days of treatment using OHI-S, PMA indices, dental hypersensitivity prevalence (DHP), dental hypersensitivity intensity (DHI), Dental Sensitivity Index (DSI), Efficacy of Dental Sensitivity Index (EDSI). In addition, the pH of saliva, the activity of lysozyme and S-IgA, and the levels of cytokines IL-1β, IL-4, IL-6, and IL-8 were determined.

RESULTS

The average value of OHI-S in the main group on the 10th day of treatment decreased from 2.25±0.12 (poor level of hygiene) to 1.47±0.09 (satisfactory level). The PMA index in the main group also tended to decrease from 32.1±1.44% (moderate degree of gingivitis) to 20.5±2.08% (mild degree) on the 10th day of treatment. The average values of DPH, DPI, EDSI and DSI in the main group had a noticeable decrease already on the 10th day from the start of treatment (from 12.3±1.66% to 2.1±1.22%; from 2.5±0.48 to 1.2±0.16; from 48.3±1.14% to 40.8±1.71%; from 42.1±2.07% to 20.8±1, 65% respectively). In the main group on the 10th and 40th day of treatment the pH values of non-stimulated and stimulated saliva stabilized (from 4.61±0.12 to 6.94±0.07 and from 5.47±0.21 to 7.42±0.24, respectively), the activity of lysozyme increased (from 45.97±1.46% to 55.19±0.96%) alongside with secretory IgA (from 0.17±0.02 to 0.33±0.21 mg/ml). Also, indicators of cytokines IL-1β, IL-4, IL-6, IL-8 tended to improve. The analysis of the control group revealed persistent mean values that did not yield to significant changes either in the course of treatment.

CONCLUSION

Thus, in patients of the main group, the results obtained indicate an improvement in the dental status and activation of cytokine regulation, providing a combination of active components of the mineral complex. In controls the method of remineralizing therapy for tooth hyperesthesia alleviated dental hypersensitivity, but without significant improvement of the laboratory results.

Comparative efficacy of BioMin-F, Colgate Sensitive Pro-relief and Sensodyne Rapid Action in relieving dentin hypersensitivity: a randomized controlled trial

Background

Dentin hypersensitivity (DH) is a sharp toothache that influences a patients' oral health-related quality of life. Oral dentifrices have been marketed for pain relief within a minute for DH. The permanent management of DH is being investigated with the remineralisation potential of bioactive agents in dentinal tubules. This study investigated the relief from pain in DH in one minute after applying over the counter (OTC) dentifrices with Pro-Argin™ and strontium acetate and directly compared them with fluoro-calcium phospho-silicate (FCPS)-based dentifrices for immediate and sustained inhibition of painful stimulus provoking DH.

Methods

A randomised, controlled, triple-blinded clinical trial was conducted with 140 participants clinically diagnosed with DH and equally randomized into four groups with parallel treatment assignment of FCPS, Pro-Argin™, 8% strontium acetate, and sodium fluoride-based OTC dentifrices, and tested for DH with air blast, mechanical, and water jet stimuli on SCHIFF cold air sensitivity scale (SCASS) and visual analogue scale (VAS) at interim efficacy intervals of one minute, three days, two, four, and six weeks, subsequently.

Results

A total of 128 participants completed the trial. All the treatment groups showed statistically significant improvement in DH with p < 0.001 relative to baseline at all time points. Pro-Argin™ showed a greater reduction in DH with mean scores of (1.34 ± 0.68) (4.20 ± 1.70) (3.05 ± 2.17) followed by strontium acetate (1.57 ± 0.81) (4.65 ± 1.87) (3.75 ± 1.97) on SCASS and VAS for mechanical and water jet stimuli, one minute after application. There was no statistically significant treatment difference between the two (p = 0.499). FCPS showed the highest reduction in DH on SCASS and VAS for waterjet stimuli with mean scores of (0.97 ± 0.68) (1.80 ± 1.73) and Pro-Argin™ on VAS for mechanical stimuli with mean scores of (2.15 ± 1.92) in six weeks.

Conclusion

OTC dentifrices with Pro-argin™ and strontium acetate are effective for immediate pain relief from DH, and FCPS could be the best possible treatment option for long term management of DH.

Trial registration

ID: NCT04249336 (https://clinicaltrials.gov/ct2/show/NCT04249336), Date of Registration: January 30, 2020 (Retrospectively registered).

The Amelogenin-Derived Peptide TVH-19 Promotes Dentinal Tubule Occlusion and Mineralization

In this study, the amelogenin-derived peptide, TVH-19, which has been confirmed to promote mineralization, was evaluated to derive its potential to induce dentinal tubule occlusion. The binding capability of fluorescein isothiocyanate (FITC)-labeled TVH-19 to the demineralized dentin surface was analyzed by confocal laser scanning microscopy (CLSM). Additionally, the sealing function of the peptide was studied through the remineralization of demineralized dentin in vitro. The adsorption results showed that TVH-19 could bind to the hydroxyapatite and demineralized dentin surfaces, especially to periodontal dentin. Scanning electron microscopy analysis further revealed that TVH-19 created mineral precipitates. The plugging rate in the TVH-19 group was higher than that in the PBS group. Moreover, energy-dispersive X-ray spectroscopy (EDX) results indicated that the calcium/phosphorus (Ca/P) ratio of the new minerals induced by TVH-19 was close to that of the hydroxyapatite. Attenuated total internal reflection-Fourier transform infrared (ATR-FTIR) spectrometry and X-ray diffraction (XRD) results indicated that the hydroxyapatite crystals formed via remineralization elongated the axial growth and closely resembled the natural dentin components. These findings indicate that TVH-19 can effectively promote dentin sealing by binding to the periodontal dentin, promoting mineral deposition, and reducing the space between the dentin tubules.

Laser therapy for dentinal hypersensitivity

BACKGROUND

Dentinal hypersensitivity is characterized by short, sharp pain from exposed dentine that occurs in response to external stimuli such as cold, heat, osmotic, tactile or chemicals, and cannot be explained by any other form of dental defect or pathology. Laser therapy has become a commonly used intervention and might be effective for dentinal hypersensitivity.

OBJECTIVES

To assess the effects of in-office employed lasers versus placebo laser, placebo agents or no treatment for relieving pain of dentinal hypersensitivity.

SEARCH METHODS

Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 20 October 2020), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library 2020, Issue 9), MEDLINE Ovid (1946 to 20 October 2020), Embase Ovid (1980 to 20 October 2020), CINAHL EBSCO (Cumulative Index to Nursing and Allied Health Literature; 1937 to 20 October 2020), and LILACS BIREME Virtual Health Library (Latin American and Caribbean Health Science Information database; from 1982 to 20 October 2020). Conference proceedings were searched via the ISI Web of Science and ZETOC, and OpenGrey was searched for grey literature. The US National Institutes of Health Ongoing Trials Register (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases.

SELECTION CRITERIA

Randomized controlled trials (RCTs) in which in-office lasers were compared to placebo or no treatment on patients aged above 12 years with tooth hypersensitivity.

DATA COLLECTION AND ANALYSIS

Two review authors independently and in duplicate screened the search results, extracted data, and assessed the risk of bias of the included studies. Disagreement was resolved by discussion. For continuous outcomes, we used mean differences (MD) and 95% confidence intervals (CI). We conducted meta-analyses only with studies of similar comparisons reporting the same outcome measures. We assessed the overall certainty of the evidence using GRADE.

MAIN RESULTS

We included a total of 23 studies with 936 participants and 2296 teeth. We assessed five studies at overall low risk of bias, 13 at unclear, and five at high risk of bias. 17 studies contributed data to the meta-analyses. We divided the studies into six subgroups based on the type of laser and the primary outcome measure. We assessed the change in intensity of pain using quantitative pain scale (visual analogue scale (VAS) of 0 to 10 (no pain to worst possible pain)) when tested through air blast and tactile stimuli in three categories of short (0 to 24 hours), medium (more than 24 hours to 2 months), and long term (more than 2 months). Results demonstrated that compared to placebo or no treatment the application of all types of lasers combined may reduce pain intensity when tested through air blast stimuli at short term (MD -2.24, 95% CI -3.55 to -0.93; P = 0.0008; 13 studies, 978 teeth; low-certainty evidence), medium term (MD -2.46, 95% CI -3.57 to -1.35; P < 0.0001; 11 studies, 1007 teeth; very low-certainty evidence), and long term (MD -2.60, 95% CI -4.47 to -0.73; P = 0.006; 5 studies, 564 teeth; very low-certainty evidence). Similarly, compared to placebo or no treatment the application of all types of lasers combined may reduce pain intensity when tested through tactile stimuli at short term (MD -0.67, 95% CI -1.31 to -0.03; P = 0.04; 8 studies, 506 teeth; low-certainty evidence) and medium term (MD -1.73, 95% CI -3.17 to -0.30; P = 0.02; 9 studies, 591 teeth; very low-certainty evidence). However, there was insufficient evidence of a difference in pain intensity for all types of lasers when tested through tactile stimuli in the long term (MD -3.52, 95% CI -10.37 to 3.33; P = 0.31; 2 studies, 184 teeth; very low-certainty evidence). Most included studies assessed adverse events and reported that no obvious adverse events were observed during the trials. No studies investigated the impact of laser treatment on participants' quality of life.

AUTHORS' CONCLUSIONS

Limited and uncertain evidence from meta-analyses suggests that the application of laser overall may improve pain intensity when tested through air blast or tactile stimuli at short, medium, or long term when compared to placebo/no treatment. Overall, laser therapy appears to be safe. Future studies including well-designed double-blinded RCTs are necessary to further investigate the clinical efficacy of lasers as well as their cost-effectiveness.

Long-Term Effectiveness of Treating Dentin Hypersensitivity with Bifluorid 10 and Futurabond U: A Split-Mouth Randomized Double-Blind Clinical Trial

Background: The definition of dental hypersensitivity is “pain derived from exposed dentin in response to chemical, thermal tactile or osmotic stimuli which cannot be explained as arising from any other dental defect or disease”. One of the treatments proposed is tubular occlusion. The aim of this in vivo split-mouth randomized clinical trial was to evaluate the clinical efficacy of a in-office application of a fluoride varnish (Bifluorid 10) and a bonding resin (Futurabond U) in adults with dentin hypersensitivity. Material and methods: A total of 180 teeth were treated with Bifluorid 10 and 160 with Futurabond U. Outcome measurements were taken one or two weeks before treatment, at baseline at the application days, at 1 week and at 1–6 months after first treatment. Results: Both treatments reduced pain intensity. Bifluorid 10 and Futurabond U have similar efficacy in reducing SCHIFF-measured pain reduction, while Bifluorid 10 is significantly more efficient for VAS-measured pain reduction, mainly due to long-term pain reduction. Patient age has a significant negative influence on pain reduction, while the influence of patient gender and BEWE of the tooth is insignificant. Conclusions: Bifluorid 10 and Futurabond U are effective in the treatment of dental hypersensitivity. The RCT was registered at the US National Institutes of Health (ClinicalTrials.gov) #NCT04813848.

In Vitro Evaluation of Desensitizing Agents Containing Bioactive Scaffolds of Nanofibers on Dentin Remineralization

This study evaluated the effect of the incorporation of bioactive nanofibers in desensitizing agents on dentin permeability. Sixty disks of dentin were randomly distributed in four groups (n = 15). Distribution was based on the desensitizing agents, fluoride varnish and self-etching adhesive, and the presence of nanofibers: C (self-etching adhesive Clearfil SE Bond), CN (Clearfil SE Bond with 1% nanofiber), D (Duraphat varnish), and DN (Duraphat varnish with 1% nanofiber). Dentin permeability was determined using hydraulic conductivity. For a qualitative analysis, confocal laser microscopy and scanning electron microscopy were performed. The C group showed the lowest hydraulic conductance (Lp%) (89.33), while the DN group showed the highest Lp% (116.06). No statistical significance was observed in the Lp% values in all groups after the treatment and 6% citric acid challenge (p > 0.239). In the images, the CN group presented a higher superficial and intratubular deposition. In addition, this group presented a more homogeneous dentin surface and wide occlusion of dentinal tubules than the other treatments. Despite there being no statistical differences among the treatments employed, the images showed that the CN group presented a higher surface and intratubular deposition compared to the other treatments, even after the acid challenge.

Acidic Monetite Complex Paste with Bleaching Property for In-depth Occlusion of Dentinal Tubules

Background

Dentin hypersensitivity (DH) is a common dental clinical condition presented with a short and sharp pain in response to physical and chemical stimuli. Currently no treatment regimen demonstrates long-lasting efficacy in treating DH, and unesthetic yellow tooth color is a concern to many patients with DH.

Aim

To develop a bi-functional material which can occlude dentinal tubules in-depth and remineralize dentin for long-lasting protection of the dentin–pulp complex from stimuli and bleach the tooth at the same time.

Methods

A mixture containing CaO, H₃PO₄, polyethylene glycol and H₂O₂ at a specific ratio was mechanically ground using a planetary ball. The mineralizing complex paste was characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Dentin was exposed to the synthesized paste for 8 h and 24 h in vitro. The mineralizing property was evaluated using SEM and microhardness tests. Red tea-stained tooth slices were exposed to the synthesized paste for 8 h and 24 h in vitro. The bleaching effect was characterized by a spectrophotometer.

Results

The complex paste had very a fine texture, was injectable, and had a gel-like property with 2.6 (mass/volume) % H₂O₂ concentration. The X-ray diffraction pattern showed that the inorganic phase was mainly monetite (CaHPO₄). The mineralizing complex paste induced the growth of inorganic crystals on the dentin surface and in-depth occlusion of dentin tubules by up to 80 μm. The regenerated crystals were integrated into the dentin tissue on the dentin surface and the wall of dentinal tubules with a microhardness of up to 126 MPa (versus 137 Mpa for dentin). The paste also bleached the stained dental slices.

Conclusion

The mineralizing complex paste is a promising innovative material for efficient DH management by remineralizing dentin and in-depth occlusion of dentin tubules, as well as tooth bleaching.

Mesoporous calcium silicate nanoparticles for superficial dental tissue reconstruction, in vitro and in vivo

The underlying dentin could be exposed to a humid atmosphere filled with bacteria if the covering enamel layer is broken because of external chemical and physical conditions. Accordingly, some diseases like bacterial invasion and dentin hypersensitivity often occur, which impact the daily life of patients. The study is aimed at evaluating the occluding effects of mesoporous calcium silicate nanoparticles (MCSNs) on the dentinal tubules in vitro and in vivo, as well as the antibacterial property and drug delivery ability when loaded with chlorhexidine (CHX) in vitro. MCSNs were synthesized according to the standard protocol. After a series of complimentary evaluations in vitro and in vivo, it was found that MCSNs and CHX–MCSNs could continually form apatite-like enamel layers on the exposed dentinal tubules and significantly reduced dentin permeability both in vitro and in vivo. Besides, MCSN and CHX–MCSN possessed low cytotoxicity in vitro, and only mild pulp inflammation was observed in two MCSNs containing groups in vivo. In addition, MCSN loaded with CHX released CHX sustainably and revealed a significant antibacterial effect against E. faecalis in vitro. Therefore, the results suggest that MCSN could be used as a promising biomaterial to occlude the dentinal tubules and carry antibiotics for avoiding further pulp infection.

MCSNs could be used as a promising biomaterial for occluding the dentinal tubules in vitro and in vivo. Also, the outstanding drug delivery and antibacterial properties enable it to carry antibiotics easily for inhibiting deeper pulp infection.

Can Desensitizing Toothpastes Also Have an Effect on Gingival Inflammation? A Double-Blind, Three-Treatment Crossover Clinical Trial

Background: Many desensitizing toothpastes exist commercially; however, few clinical trials have investigated their anti-inflammatory effects. This study aimed to evaluate the anti-inflammatory effect and patient appreciation of two toothpastes containing desensitizing agents: (1) a zinc-carbonate-hydroxyapatite nanoparticle (CHA) and (2) a calcium sodium phosphosilicate bioactive glass (CSPS). Methods: CHA and CSPS were compared with an anti-inflammatory and antibacterial herbal based toothpaste (HB). The aims were accomplished by comparing the following outcomes: (1) the reduction in plaque and bleeding score (Full Mouth Plaque Score (FMPS) and Full Mouth Bleeding Score (FMBS), respectively); (2) the antibacterial activity (AbA) of the toothpaste by saliva samples; (3) the patient appreciation score (Visual Analogue Scale; VAS). Clinical parameters were assessed at baseline and 14 days post-treatment. Results: The final sample consisted of 25 subjects, aged between 20 and 58 years. Although no differences in FMPS were reported (p > 0.05), both desensitizing toothpastes showed an improvement in FMBS. CSPS and HB recorded more AbA compared to CHA (p < 0.05). Moreover, HB resulted in a higher VAS score than both desensitizing toothpastes (p < 0.05). Conclusion: In conclusion, only CSPS displayed a similar anti-inflammatory effect compared to HB. Despite the low VAS score, CSPS could be considered as a valid and effective toothpaste in subjects with both dentin hypersensitivity and inflamed gums, highlighting its utility in clinical practice.

Clinical Efficacy of Different Dentin Desensitizers

CLINICAL RELEVANCE

Teethmate Desensitizer, Clinpro White Varnish, Shield Force Plus, and Gluma could be recommended for treating dentin hypersensitivity in terms of clinical efficacy.

SUMMARY

Objective: The aim of this study was to evaluate the clinical efficacy of widely used dentindesensitizing agents (DDAs) (Teethmate Desensitizer, Clinpro White Varnish, Shield Force Plus, and Gluma) in the treatment of dentin hypersensitivity (DH) according to different evaluation parameters over a four-week follow-up period.Methods and Materials: This study was a randomized, single-center, controlled, parallel group study involving 144 teeth in 40 subjects. The baseline DH levels of the subjects were determined using different evaluation parameters. Daily life hypersensitivity and evaporative air stimulus hypersensitivity scores were recorded using a visual analog scale (VAS), and tactile hypersensitivity scores were recorded using a Yeaple probe and measured in grams and on the VAS. Subjects who experienced evaporative air stimulus DH (30-80 mm on the VAS) and tactile hypersensitivity (10-50 g with the Yeaple probe) were included in the study. After application of the DDAs, these evaluation parameters were recorded throughout the follow-up period (immediately after application and at one day and two and four weeks post-application).Results: All four DDAs demonstrated clinical dentin-desensitizing effects throughout the follow-up period according to evaporative air hypersensitivity, tactile sensitivity (g-VAS), and daily life hypersensitivity scores (p<0.05). Only Clinpro White Varnish had tactile sensitivity (g) scores that were similar at baseline and the one-day follow-up (p>0.05). A comparison of DH-reducing effects among the DDAs revealed that they yielded different results immediately after application and at the one-day follow-up time point, depending on which evaluation parameter was used. However, all DDAs showed similar DH-reducing effects at the two- and four-week follow-up time points.Conclusions: Teethmate Desensitizer, Clinpro White Varnish, Shield Force Plus, and Gluma DH showed clinical efficacy for four weeks. DDAs may produce inconsistent clinical evaluation scores not only across different evaluation parameters but also between early and later follow-up time points.

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.

Desensitizing Toothpastes for Dentin Hypersensitivity: A Network Meta-analysis

The goal of this systematic review and network meta-analysis was to compare the relative effects of toothpaste formulations for dentin hypersensitivity (DH), tested in randomized controlled trials (RCTs). We searched 7 databases to February 2019. Paired reviewers independently screened studies, extracted data, and performed risk of bias assessment. The outcome of interest was painful response measured through tactile, cold, and air stimuli. We conducted a random-effects Bayesian network meta-analysis using standardized mean difference (SMD) and their credible intervals (CIs) as the measure of effect for each pain stimuli. We assessed certainty of evidence using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. We included 125 RCTs (12,541 patients). For tactile stimulus, the following active ingredients showed large beneficial effects compared to fluoride with moderate certainty of evidence (SMD; 95% CI): potassium + stannous fluoride (SnF₂) (3.05; 1.69-4.41), calcium sodium phosphosilicate (CSP) (2.14; 0.75-3.53), SnF₂ (2.02; 1.06-2.99), potassium + hydroxyapatite (2.47; 0.3-4.64), strontium (1.43; 0.46-2.41), and potassium (1.23; 0.48-1.98). For cold stimulus, CSP showed large beneficial effects compared to fluoride (3.93; 0.34-7.53) with moderate certainty; for air stimulus, arginine (2.22; 1.45-2.99), potassium + hydroxyapatite (2.44; 0.33-4.55), potassium + SnF₂ (2.28; 0.87-3.69), CSP (1.98; 0.99-2.98), and SnF₂ (1.9; 1.03-2.77) showed large beneficial effects compared to fluoride with moderate to high certainty. Most toothpaste formulations showed evidence of superiority against placebo or fluorides (amine fluoride, sodium monofluorophosphate, or sodium fluoride). CSP was most beneficial for all 3 stimuli with high to moderate certainty. SnF₂ alone and potassium combined with SnF₂ or hydroxyapatite were beneficial for tactile and air stimulus with high to moderate certainty. Arginine was beneficial for air stimulus, and strontium and potassium were beneficial for tactile stimulus, with moderate certainty.

Brazilian dentists' perception of dentin hypersensitivity management

The aim of this study was to investigate how Brazilian dentists perceive and manage dentin hypersensitivity (DH) in their clinical routine. A 13-item questionnaire-based survey was developed and sent electronically to a convenience sample of dentists. The questionnaire assessed the personal and dental practice characteristics of the sample, the occurrence of DH in their daily clinical practice, and management strategies. The data were analyzed descriptively and together with the chi-square test (a = 0.05). A total of 353 responses were obtained from September 2017 to March 2018. Of all the respondents, 62% were females, 49.9% reported fewer than five years of dental practice, and 70.5% were self-identified as private practitioners. Most of the dentists reported an estimated frequency (30-60%) of patients with DH in their practice. The most frequently cited (91.79%) trigger of DH was air blast and/or scratching with a probe. The first-choice strategy to manage DH was a dentin desensitizer (48.16%). The number of years in clinical practice did not influence DH relapse frequency (p = 0.76) significantly, or consider DH treatment as a problem (p = 0.22). The present findings indicate that, regardless of clinical experience, dentists in Brazil still consider DH management a challenge in their daily dental practice. In addition, the results suggest that guidelines should be developed to disseminate the available knowledge regarding this condition in ways that may influence decision-making processes among practitioners.

Laboratory evaluation of dentin tubule occlusion after use of dentifrices containing stannous fluoride

The purpose of this study was to examine the effect of desensitizing dentifrices containing stannous fluoride (SnF₂) on dentinal tubule occlusion. Two experimental dentifrices with the same ingredients but different SnF₂ concentrations (Group II, 0.4% w/w; Group III, 0.454% w/w) were used; distilled water was used in the control group (Group I). Third molars were collected from Japanese and American dental patients. The crowns were removed and sectioned to obtain dentin discs, which were further cut into quarters. Thirty-six specimens each from Japanese and American patients were divided into three sets (n = 12 each) and assigned to each of the three treatment groups. The specimens were brushed for 10 s twice per day for 4 days. After treatment, the discs were observed by scanning electron microscopy, and the extent of dentinal tubule occlusion in the images was expressed on a five-point categorical scale. Group II and III specimens from Japanese and American patients showed greater dentinal tube occlusion than those from Group I, but the differences were not statistically significant. The present results suggest that both SnF₂ concentrations mitigate dentin hypersensitivity, regardless of patient ethnicity.

Amyloid-Like Rapid Surface Modification for Antifouling and In-Depth Remineralization of Dentine Tubules to Treat Dental Hypersensitivity

Exposure of dentinal tubules (DTs) leads to the transmission of external stimuli within the DTs, causing dental hypersensitivity (DH). To treat DH, various desensitizers have been developed for occluding DTs. However, most desensitizers commercially available or in development are only able to seal the orifices, rather than the deep regions of the DTs, thus lacking long-term stability. Herein, it is shown that the fast amyloid-like aggregation of lysozyme (lyso) conjugated with poly(ethylene glycol) (PEG) (lyso-PEG) can afford a robust ultrathin nanofilm on the deep walls of DTs through a rapid one-step aqueous coating process (in 2 min). The resultant nanofilm provides a highly effective antifouling platform for resisting the attachment of oral bacteria such as Streptococcus mutans and induces remineralization in the DTs to seal both the orifices and depths of the DTs by forming hydroxyapatite (HAp) minerals in situ. Both in vitro and in vivo animal experiments prove that the nanofilm-coated DTs are occluded with a depth of over 60 ± 5 µ m, which is at least 6 times deeper than that reported in the literature. This approach thus demonstrates the concept that an amyloid-like proteinaceous nanofilm can offer an inexpensive, rapid, and efficient therapy for treating DH with long-term effect.

Antimicrobial Activity of Protamine-Loaded Calcium Phosphates against Oral Bacteria

Protamine is an antimicrobial peptide extracted from fish. In this study, we loaded protamine onto dicalcium phosphate anhydride (DCPA), a dental material. Protamine was loaded by stirring DCPA into a protamine solution. To explore the antimicrobial activity of the materials, we cultivated Streptococcus mutans on fabricated discs for 24 h. When S. mutans was cultivated on the discs under no sucrose conditions, the loaded protamine was not released, and the ratio of dead bacteria increased on the surface of P (125) DCPA (half of the saturated level of protamine (125 ppm protamine) was loaded). Aside from P (500) DCPA (saturated level of protamine was loaded), some protamine was released, and the number of planktonic bacteria in the supernatant decreased. Using medium containing 1% sucrose, the release of protamine was promoted from P (125) DCPA due to lowered pH. However, lowering of the pH decreased the antimicrobial activity of protamine. On the other hand, P (500) DCPA released protamine before the pH was lowered, and biofilm formation was inhibited. The loaded protamine expressed antimicrobial activity, both on the surface of the materials and in the surrounding environment. The interaction of loaded protamine with calcium phosphates could promote the application of protamine in the dental field.

A randomised controlled trial to investigate the efficacy of an oxalate strip for the management of dentine hypersensitivity pain

OBJECTIVES

To compare a 3.14% potassium oxalate strip and 8% arginine calcium carbonate toothpaste for the reduction of dentine hypersensitivity after 2 and 4 weeks.

METHODS

This was an examiner-blind, parallel study in 80 healthy adults with dentine hypersensitivity (Schiff score >2) in >1 tooth. After acclimatisation, participants were randomised to the oxalate desensitising strip with fluoride toothpaste or the arginine desensitising toothpaste control which also contained fluoride. Products were applied under supervision of study staff after measuring baseline sensitivity, thereafter the strip or control toothpaste (fingertip application) was applied after 1 and 2 weeks, and teeth brushed twice-daily with the fluoride (test group) or the fluoridated arginine control toothpaste. Sensitivity was assessed following airblast (Schiff and VAS) and tactile stimuli (Yeaple probe) at baseline, 2 and 4 weeks.

RESULTS

Both groups showed significant reductions from baseline in VAS, Schiff and Yeaple sensitivity scores after 2 and 4 weeks (p < 0.0005). The oxalate group had significantly lower Schiff and higher Yeaple probe scores compared to control after both time points (p < 0.0002 and p < 0.05), but while scores favoured the oxalate group, there were no significant differences in VAS.

CONCLUSIONS

This study demonstrated application of a 3.14% potassium oxalate strip combined with toothbrushing with paste was more effective in pain management of dentine hypersensitivity than brushing with arginine toothpaste.

CLINICAL SIGNIFICANCE

Treatment of sensitive teeth with the oxalate strip reduced dentine hypersensitivity after 2 and 4 weeks to a significantly greater degree than a positive control sensitivity toothpaste demonstrating that oxalate strips are an effective targeted treatment for dentine hypersensitivity sufferers.

Grit blasted aggregates of hydroxyl apatite functionalized calcium carbonate in occluding dentinal tubules

Objectives

This study aimed to investigate the effects of using hydroxyl apatite functionalized calcium carbonate (FCC) particles on occluding dentinal tubules.

Methods

Dentine specimens extracted from eighteen human molars with exposed dentinal tubules were divided into three groups (n = 6/group): a) Cut surface with smear layer; b) EDTA (smear layer removed with 17% EDTA for 1 min); and c) Grit blasted functionalized calcium carbonate (FCC) with and air pressure of 280 kPa. Microscopic dentinal tubule occlusion, tubule diameter and tubule area were evaluated using scanning electron microscopy (SEM) before and after grit blasting. Biomineralization of specimens was carried out in a simulated body fluid (SBF). Elemental analysis of occluding materials was carried out using energy-dispersive X-ray spectroscopy (EDX). X-ray diffraction (XRD) analysis was performed to demonstrate the crystal structure of the biomineralized layer on dentine.

Results

FCC particles showed penetration into the dentinal tubules by breakage of their original particle shape and size. EDTA treated surface had higher number and larger size tubules than those with smear layer or grit blasted (p < 0.005). SEM-EDX analysis revealed mineral precipitation of calcium phosphate on the SBF immersed dentin specimens. XRD analysis showed typical crystal structure of hydroxyl apatite for the biomineralized surface layer on dentine.

Conclusions

Grit blasted FCC particles initially occluded effectively the opened dentinal tubules and biomineralization occurred in tubules primarily occluded by the FCC particles. However, in the optimal in vitro conditions in SBF, no difference between biomineralization was found between the grit blasted surface and the control surface.

Clinical significance

Several materials and methods have been established for treatment of dentinal hypersensitivity although a golden standard treatment has not been discovered. Grit blasted functionalized calcium carbonate has a potential to occlude and remineralize exposed dentinal tubules. This could offer a more biological approach on treatment of dentin hypersensitivity.

The Effect of Desensitizing Toothpastes and Coffee Staining on the Optical Properties of Natural Teeth and Microhybrid Resin Composites: An In-Vitro Study

Objective

To evaluate the effect of different desensitizing toothpastes and coffee staining on the discoloration rate of natural human tooth and composite materials.

Materials and Methods

A total of 56 human teeth and 56 composite specimens were used. After initial color measurements were taken, specimens and teeth were exposed to simulated toothbrushing with six desensitizing toothpastes containing different active ingredients: stannous fluoride, strontium acetate, potassium citrate and hydroxyapatite, cetylpyridinium chloride, arginine, and novamin. Specimens were then exposed to coffee staining. Throughout the staining procedure, the storing solution was refreshed every day and the specimens were brushed with the tested toothpastes. Color measurements and changes were recorded at each stage and analyzed with one-way ANOVA, Dunnett tests, and paired sample t-test (p<0.05).

Results

The largest color change was obtained with the stannous fluoride toothpaste after coffee staining for natural teeth (2.6 ΔE ₀₀ ^⁎) and composite specimens (3.1 ΔE ₀₀ ^⁎). Coffee staining resulted in significant changes for ΔE ₀₀ ^⁎ values of all groups, except for natural teeth brushed with a novamin-based (p= 0.06) toothpaste. For composite specimens, only the stannous fluoride and cetylpyridinium chloride-based toothpastes resulted in significant color changes relative to the control group. ΔL^⁎ and Δb^⁎ values were also increased after staining for all groups (p<0.05).

Conclusions

Desensitizing toothpastes alone did not cause perceptible color changes; however, in combination with coffee staining, it tended to increased discoloration for both composites and natural teeth.

Biomimetic regulation of dentine remineralization by amino acid in vitro

OBJECTIVE

The aim of this study was to evaluate the effect of conditioning solutions containing DL-aspartic amino (Asp) on dentine remineralization induced by bioactive glass 45S5 (BAG) in a simulated oral environment.

METHODS

Sixty dentine discs from human third molars were used. Dentine specimens were treated with ethylene diamine tetraacetic acid (EDTA) to create a partially demineralization model and randomly divided to 4 groups: Artificial saliva (AS) group, Asp group (pretreated with Asp and remineralized with distilled water), BAG group (pretreated with distilled water and remineralized by BAG), Asp-BAG group (pretreated with Asp and remineralized by BAG). Each samples were measured at various time points, and at the end of the experiment, 6% citric acid challenge were taken. The remineralization characteristics were analyzed by using the spectroscopic data from attenuated total reflectance spectroscopy (ATR-IR) and Raman spectroscopy. The micro-morphology and structure were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). Dentine permeability was measured before and after each treatment to evaluate the resistance of remineralized layer to acid and simulated oral environment.

RESULTS

Both BAG and Asp-BAG groups significantly reduced dentine permeability and formed enamel-like apatite layers on dentine surface. For the mineralization of BAG, Asp showed inhibition effect. The 7-day mineral matrix area ratio in BAG group (12.54±2.29) was lower than the value in the Asp-BAG group (17.77±2.27) (p<0.05) and the Raman intensity (RI%) in Asp-BAG Group (1.49±0.26) was also significantly higher than that of BAG group (1.34±0.14) (p<0.05). According to permeability test, the apatite layer in BAG group and Asp-BAG group effectively occluded the dentinal tubules (p<0.05) and had certain acidic resistance (p>0.05). Furthermore, adsorbed acidic amino acid on hydroxyapatite (HAP) altered the crystal to increase into a larger size in diameter during crystal growth.

SIGNIFICANCE

The study demonstrated that a superior remineralization efficacy of BAG with Asp pretreatment on dentine.

Are Desensitizing Toothpastes Equally Biocompatible and Effective Against Microorganisms?

The aims of this study were evaluate cytotoxicity, genotoxicity, antimicrobial activity of desensitizing toothpastes compared to a common one and the surface roughness of tooth enamel submitted to brushing with these toothpastes. Samples of three desensitizing toothpastes (Colgate Sensitive, Sensodyne and Oral B Sensitive) and common toothpaste (Colgate) were placed in contact with gingival human fibroblasts. Cytotoxicity and genotoxocity were measured by MTT assay and micronucleus test. Antimicrobial activity of the toothpastes extracts against C. albicans, S. mutans and S. aureus were assessed. For surface roughness evaluation, bovine teeth were submitted to 10.000 brushing cycles. The results were analyzed statically using Mann-Whitney U, ANOVA and Z tests (p<0.05). All toothpastes caused cytotoxic effect to the cells (p<0.05), except Colgate Sensitive. The toothpastes did not increase the number of micronuclei compared to the untreated control group. Colgate eliminated all the evaluated microorganisms at lower concentrations compared to Colgate Sensitive and Oral B Sensitive, which were not able to eliminate S. aureus. Sensodyne did not reach the minimum microbicidal concentration. The surface roughness of tooth enamel increased after brushing with Colgate Sensitive and Oral B Sensitive, however the comparison between groups showed no difference on the enamel surface roughness presented by desensitizing toothpastes when compared with the common one (p>0.05). Based on these results, we can conclude that although none toothpaste has induced genotoxicity, Colgate Sensitive was also not cytotoxic. Colgate was the most effective against the microorganisms, and there were no differences on the enamel surface roughness between the groups.

A randomized clinical trial on the efficacy of a new oxalate-containing sensitivity relief strip following professional vs self-application

OBJECTIVES

The purpose of this study was to determine the efficacy of 3.14% dipotassium oxalate monohydrate-containing strip on the relief of dentinal hypersensitivity (DH). A second objective was to determine whether there was a difference in DH levels when the strip was self-applied vs applied by a dental professional.

METHODS

Sixty subjects were randomized into self-applied, professionally applied or placebo-strip groups. Dentinal hypersensitivity was evaluated by a blinded examiner, using the Schiff Air Scale (SAS). A verbal rating scale (VRS) was also used to measure the subjects' perception of pain. Measures were taken at baseline, 30 minutes, 4 and 8 weeks post-treatment.

RESULTS

There was a significant reduction in DH in all three groups (P ≤ .05) at 30 minutes and 8 weeks post-treatment. At the 4-week follow-up, only the self- and professionally applied (active ingredient) groups had a significant reduction in DH compared to baseline. When comparing the reduction in DH levels between groups, the only significant difference occurred between the professionally applied treatment group and the placebo group at the 4-week follow-up. There were no significant differences in DH reduction levels achieved between the self- and professionally applied groups (P > .05).

CONCLUSIONS

This study confirmed the short-term (4 weeks) effectiveness of a single application of 3.14% dipotassium oxalate monohydrate-containing strip. Self- and professional application were not shown to be different.

Dentinal tubules occluded by bioactive glass-containing toothpaste exhibit high resistance toward acidic soft drink challenge

BACKGROUND

Dentine hypersensitivity is a common problem attributed by patent dentinal tubules. Ingredients incorporated in toothpastes aim to occlude patent dentinal tubules to minimize the dentine hypersensitivity. However, frequent consumption of acidic soft drinks may reverse the dentinal tubules' occlusion. In this in vitro study, the efficacy of dentinal tubules occluded by commercially available toothpastes to withstand different durations of an acidic soft drink challenge was investigated.

METHODS

One hundred and twenty dentine discs were divided into three groups. The discs from each group were brushed with toothpaste containing bioactive glass, arginine and control toothpaste. Each group was then divided into four subgroups and exposed to acidic soft drink over four different time durations.

RESULTS

The scoring and the percentage of occluded dentinal tubules by Novamin-containing toothpaste was significantly better compared with arginine or the control toothpaste. Acidic soft drink challenge reduced the extent of dentinal tubules occlusion along with time. Dentinal tubules occluded by Novamin-containing toothpaste withstand the acidic challenge comparatively for a longer period.

CONCLUSIONS

The findings demonstrated that occlusion of dentinal tubules is more efficient by the bioactive glass-containing toothpaste and thus may contribute to its better resistance to acidic soft drink challenge.

Evaluation of ex vivo effectiveness of commercial desensitizing dentifrices

BACKGROUND

Dentin hypersensitivity is a short, severe pain with fast onset. Therapy aims to either prevent or decrease neural transmission or physically occlude the dentinal tubules. This study aimed to evaluate the effectiveness of commercial desensitizing dentifrice by means of an ex vivo method.

MATERIAL AND METHODS

Samples (n=8 lower human premolars for each group) were randomly allocated into: G1- brushing with Colgate®Sensitive Pro-Relief; G2- brushing with Sensodyne®Rapid Relief; G3- brushing with Sensodyne®Repair & Protect; and G4- brushing with Colgate®Maximum Cavity Protection. The test bodies were submitted to simulated toothbrushing and dentifrices were analyzed regarding their hydrodynamic size, polydispersity index (PI) and zeta potential. Specimens were evaluated using: scanning electron microscopy (SEM); spectroscopy energy dispersive X-ray (EDS); and profilometry. A qualitative analysis of the photomicrographs and topographies was performed.

RESULTS

The dentifrices showed statistical similar physical and chemical characteristics. They also demonstrated obliteration of dentinal tubules when micrographs were observed. Regarding the chemical elements present in the dentin samples, there was a statistically significant difference between the control and experimental surfaces in the four groups.

CONCLUSIONS

Joint data analysis shows that the desensitizing dentifrice showed better results with regards to the obliteration of dentinal tubules compared to positive and negative controls. Key words:Dentin hypersensitivity, dentin desensitizing agents, toothpastes.

Randomized clinical trial of the effect of NovaMin and CPP-ACPF in combination with dental bleaching

OBJECTIVE

This randomized, controlled, double-blind clinical study evaluated the effect of calcium sodium phosphosilicate (NovaMin) and casein phosphopeptide-amorphous calcium phosphate with fluoride (CPP-ACPF) on the prevention of post-operative sensitivity and on the effects of clinical bleaching treatment.

MATERIAL AND METHODS

Sixty volunteers were selected according to inclusion and exclusion criteria and were randomly assigned into three groups (n=20): CG (control group) patients, who were treated with 35% hydrogen peroxide; NOVAG (NovaMin group) patients, who were treated with 35% hydrogen peroxide followed by the application of NovaMin; and CPPG (CPP group) patients, who were treated with 35% hydrogen peroxide followed by the application of CPP-ACPF. Both bioactive agents were applied for five minutes. An evaporative stimulus associated with a modified visual scale was used to analyze sensitivity 24 hours after each bleaching session. The color evaluation was performed on the maxillary central incisors using a spectrophotometer. Associations between the intervention group, bleaching session, and reported sensitivity were tested using Chi-square partitioning.

RESULTS

Color change values (ΔE) were analyzed using analysis of variance (ANOVA). The significance level used for both tests was 5%. In the intragroup assessment, the Friedman test showed that only the CPP-ACPF group showed no statistically significant difference (p<0.05) between baseline and first bleaching session. In the intergroup assessment, the Kruskal-Wallis test showed that the CPPG had less postoperative sensitivity after the first session, when compared to the other groups (p<0.05). Color change analysis (ΔE) showed a significant difference between the means obtained in the different bleaching sessions in all groups (p<0.05).

CONCLUSIONS

This study showed that the combination of CPP-ACPF with 35% hydrogen peroxide significantly reduced post-operative sensitivity in the first session, compared with the other evaluated treatments. The association of CPP-ACPF and NovaMin did not affect the color change induced by tooth bleaching.

Structural analysis of fluorine-containing bioactive glass nanoparticles synthesized by sol-gel route assisted by ultrasound energy

In the last decades, studies about the specific effects of bioactive glass on remineralization of dentin were the focus of attention, due to their excellent regenerative properties in mineralized tissues. The incorporation of Fluorine in bioactive glass nanoparticles may result in the formation of fluorapatite (FAP), which is chemically more stable than hydroxyapatite or carbonated hydroxyapatite, and therefore is of interest for dental applications. The aim of this study was to synthesize and characterize a new system of Fluorine-containing bioactive glass nanoparticles (BGNPF). A sol-gel route assisted by ultrasound was used for the synthesis of BGNPF. The particles obtained were characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), atomic force microscopy (AFM), X-ray diffraction (XRD), dynamic light scattering (DLS), nitrogen adsorption, and X-ray photoelectron spectroscopy (XPS). SEM micrographs showed that the particles are quite uniform spherical nanostructures, occurring agglomeration or partial sinterization of the particulate system after heat treatment. XRD and XPS analysis results suggest the formation of fluorapatite crystals embedded within the matrix of the bioactive glass nanoparticles. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 360-366, 2018.

Evaluation of Five Different Desensitizers: A Comparative Dentin Permeability and SEM Investigation In Vitro

BACKGROUND/OBJECTIVE

The purpose of this study was to evaluate the efficacy and durability of five different dentin desensitizers (Gluma Desensitizer Powergel, Bifluorid 12, Gluma Self Etch Bond, D/Sense Crystal, Nupro Sensodyne Prophylaxis Paste with Novamin) on tubule occlusion and dentin permeability reduction in vitro.

METHOD

The quantitative changes in permeability of 100 dentin discs were measured after desensitizer treatments and following post-treatments of 6% citric acid challenge for 1 min or immersion in artificial saliva for 24 hours under hydrostatic pressure generated by a computerised fluid filtration meter. Qualitative SEM analyses were also carried out.

RESULTS

Dentin permeability decreased after desensitizer application in all groups. Nevertheless, only the difference between 'Gluma Self Etch Bond' and 'Nupro Sensodyne Prophylaxis Paste with Novamin' groups was significantly different (p<0.05). Dentin permeability increased significantly after post-treatments (p<0.05). There was no statistically difference among the citric acid-subgroups (p>0.05). Of all the artificial saliva-subgroups, only the difference between 'D/Sense Crystal' and 'Bifluorid 12' was significantly different (p<0.05). In SEM analysis, morphological changes were detected on the dentin surface and within the tubules following desensitizer treatments and post-treatments.

CONCLUSION

All the desensitizers significantly reduced dentin permeability by changing the morphology of the dentin surface and/or dentinal tubules. Following post-treatments, there was some reduction in the efficacy of the desensitizers which was represented by the reduction in permeability values. SEM analysis revealed some physical changes in the dentin structure which can partly give an explanation to the reduced efficacy of tested desensitizers.