Dentinal Tubular Occlusion Research Articles

Preventive dental erosion with silver diamine fluoride: An in vitro study

ObjectivesTo evaluate the erosion preventive effect of 38 % silver diamine fluoride (SDF) solution in enamel and dentin of human permanent teeth. MethodsNinety enamel and ninety dentin blocks were prepared from permanent molars and allocated into three groups. Gp-SDF received a one-off application of 38 % SDF solution. Gp-SNF received a one-off application of a solution containing 800 ppm stannous chloride and 500 ppm fluoride. Gp-DW received a one-off application of deionized water. The blocks were submitted to acid challenge at pH 3.2, 2 min, 5 times/day for 7 days. All blocks were immersed in human saliva between cycles for one hour. The crystal characteristics, percentage of surface microhardness loss (%SMHL), surface loss, and elemental analysis and surface morphology were examined by X-ray diffraction (XRD), microhardness test, non-contact profilometry, and energy-dispersive X-ray spectroscopy (EDS) and scanning electron microscopy (SEM), respectively. Data of%SMHL and surface loss were analyzed by one-way ANOVA. ResultsXRD spectra revealed that fluorapatite and silver compounds formed in Gp-SDF, while fluorapatite and stannous compounds formed in Gp-SNF. Gp-DW presented only hydroxyapatite. The median (interquartile range) of%SMHL in Gp-SDF, Gp-SNF and Gp-DW were 27.86(3.66), 43.41(2.45), and 46.40(3.54) in enamel (p< 0.001), and 14.21(1.57), 27.99(1.95), and 33.18(1.73) in dentin, respectively (p < 0.001). The mean (standard deviation, μm) of surface loss of Gp-SDF, Gp-SNF, and Gp-DW were 2.81(0.59), 4.28(0.67), and 4.63(0.64) in enamel (p < 0.001) and 4.13(0.69), 6.04(0.61), and 7.72(0.66) in dentin, respectively (p < 0.001). SEM images exhibited less enamel corruption and more dentinal tubular occlusion in Gp-SDF compared to Gp-SNF and Gp-DW. EDS analysis showed silver was detected in Gp-SDF while stannous was detected in the dentin block of Gp-SNF. Conclusion38 % SDF yielded superior results in protecting enamel and dentin blocks from dental erosion compared to SNF and DW. Clinical significanceTopical application of 38 % SDF is effective in preventing dental erosion in human enamel and dentin.

Evaluation of the Efficacy of LASER, Desensitizing Agents, and their Combined Effect on Dentinal Hypersensitivity in Bicuspids: In Vitro Study.

This study aimed to know the potential of diode light amplification by stimulated emission of radiation (LASER) and desensitizing agents on blocking the dentinal tubules, which may further help in reducing the most common dental problem named dentinal hypersensitivity (DH). Sixty human permanent bicuspids were selected, and preparation was performed in the cervical region measuring 2.5 mm × 2.5 mm × 2.5 mm, followed by acid etching for 15 seconds. These are then divided according to the groups mentioned: group 1-nano-hydroxyapatite (HA) was applied for 15 minutes; group 2-biosilicate was applied for 15 minutes; group 3-diode LASER application was performed twice for 60 seconds in noncontact mode; group 4-nano-HA plus diode LASER application; and group 5-biosilicate plus diode LASER application. The same procedure was followed on the 1st, 7th, and 14th days and then rinsed and stored in artificial saliva, and the saliva was changed every 24 hours. The dentinal tubular occlusion was observed under a scanning electron microscope (SEM) after the 14th day. The maximum dentinal tubular occlusion was observed in group 4, where nano-HA and diode LASER application was performed. All the investigated treatment groups have promising occluding potential, but the maximum was found in group 4 >group 5 >group 3 >group 1 >group 2. LASER plus desensitizing together prove to be potent and effective in reducing dentinal tubular diameter.

Effect of Commercially Available Nano-Hydroxyapatite Containing Desensitizing Toothpaste and Mouthwash on Dentinal Tubular Occlusion: A SEM Analysis.

The aim of this in vitro study was to evaluate and compare the dentinal tubule occlusion using nano-hydroxyapatite (n-HAP) containing toothpaste and mouthwash under a scanning electron microscope. The specimens were randomly divided into two groups with five specimens each: group 1-toothpaste group and group 2-mouthwash group. The percentage of the occluded dentinal tubules was assessed at the baseline, 7th, 14th, 21st, and 28th days under a scanning electron microscope. The toothpaste group showed a higher percentage of occluded dentinal tubules as compared to the mouthwash group at the 7th, 14th, 21st, and 28th days, respectively. It can be concluded that brushing twice daily with n-HAP containing toothpaste for duration of 28 days produced good dentinal tubule occlusion.

Comparative evaluation of efficacy of diode laser and two commercially available desensitizing toothpastes for dentinal tubular occlusion

Purpose: Dentinal hypersensitivity is a common clinical condition associated with exposed dentinal surfaces. Dentinal tubules can be entirely blocked after irradiation by 980-nm diode laser, with no significant morphological alterations after radiation. The use of toothpastes containing Potassium Nitrate and Calcium Hydroxyapatite reduces dentinal hypersensitivity. The main purpose of this study was to evaluate and compare the efficacy of Diode Laser and two Desensitizing Toothpastes for Dentinal Tubular Occlusion by Scanning Electron Microscopy (SEM). Methods: Twelve extracted premolars were divided into two halves each obtaining twenty-four dentin discs. Specimens were etched with 17% phosphoric acid to expose the tubules and were divided into four groups: i.e., Group A: Application of Diode Laser, Group B: Application of SHY-XT toothpaste, Group C: Application of Biomed toothpaste and Group D: Application of Distilled water. After treatment, quantitative analysis of occluded dentinal tubules was done by SEM analysis. Results: The mean values of total dentinal tubular occlusion in Groups A, B, C and D were 0.42, 0.86, 2.14, 4.07 respectively which was statistically significant (p&lt;0.001*). Diode laser (Group A) yielded a significant occlusion of the dentinal tubules when compared to the two desensitizing toothpastes (Groups B and C).

Assessment of the Efficacy of Different Desensitizing Agents on Dentinal Tubules Occlusion- An In vitro Study.

Aim:The aim of the current research was to evaluate the effectiveness of three desensitizing agents on the occlusion of dentinal tubules.Materials and Methods:Eighty human maxillary and mandibular permanent premolar teeth that were subjected to extraction in the course of orthodontic treatment were utilized in this study. The teeth were subjected to sectioning by employing a double-sided diamond disk. A block was procured from every even cervical dentinal surface with dimensions of 4 mm × 4 mm × 3 mm (L × B × H) by sectioning the tooth transversely. Further, 35% phosphoric acid was utilized for 30 s to cause dentinal etching, thereby exposing the dentinal tubules. The blocks of dentin were assigned at random to one of the following four groups (n = 20): group I: control, group II: bioactive glass containing desensitizing agent, group III: 1% nano-hydroxyapatite containing desensitizing agent, group IV: tri-calcium phosphate-containing desensitizing agent. The exterior of the specimens was scanned and evaluated using a scanning electron microscope.Results:1% nano-hydroxyapatite-containing desensitizing agent (2.04 ± 0.08) exhibited higher mean dentinal tubular blockage, followed by the bioactive class-containing desensitizing substance (2.26 ± 0.19), tri-calcium phosphate desensitizing agent (2.84 ± 0.10), and the control group (4.18 ± 0.12) in that order. Amid the experimental groups employing the various desensitizing substances, there were significant differences statistically with P < 0.001.Conclusion:The current research concluded that each of the three desensitizing agents was efficient in dentinal tubular occlusion regardless of their different chemical constitution. However, it was noted that 1% nano-hydroxyapatite-containing desensitizing agent was marginally superior to the bioactive glass- and tri-calcium phosphate-containing desensitizing agents.

Assessment of the efficacy of different desensitizing agents on dentinal tubules occlusion- An In vitro study

Aim: The aim of the current research was to evaluate the effectiveness of three desensitizing agents on the occlusion of dentinal tubules. Materials and Methods: Eighty human maxillary and mandibular permanent premolar teeth that were subjected to extraction in the course of orthodontic treatment were utilized in this study. The teeth were subjected to sectioning by employing a double-sided diamond disk. A block was procured from every even cervical dentinal surface with dimensions of 4 mm × 4 mm × 3 mm (L × B × H) by sectioning the tooth transversely. Further, 35% phosphoric acid was utilized for 30 s to cause dentinal etching, thereby exposing the dentinal tubules. The blocks of dentin were assigned at random to one of the following four groups (n = 20): group I: control, group II: bioactive glass containing desensitizing agent, group III: 1% nano-hydroxyapatite containing desensitizing agent, group IV: tri-calcium phosphate-containing desensitizing agent. The exterior of the specimens was scanned and evaluated using a scanning electron microscope. Results: 1% nano-hydroxyapatite-containing desensitizing agent (2.04 ± 0.08) exhibited higher mean dentinal tubular blockage, followed by the bioactive class-containing desensitizing substance (2.26 ± 0.19), tri-calcium phosphate desensitizing agent (2.84 ± 0.10), and the control group (4.18 ± 0.12) in that order. Amid the experimental groups employing the various desensitizing substances, there were significant differences statistically with P < 0.001. Conclusion: The current research concluded that each of the three desensitizing agents was efficient in dentinal tubular occlusion regardless of their different chemical constitution. However, it was noted that 1% nano-hydroxyapatite-containing desensitizing agent was marginally superior to the bioactive glass- and tri-calcium phosphate-containing desensitizing agents.

In vitro comparative SEM analysis of nano-hydroxyapatite toothpaste and diode laser: evaluation of efficacy of dentinal tubular occlusion

ENWEndNote BIBJabRef, Mendeley RISPapers, Reference Manager, RefWorks, Zotero AMA Shamel M, El Banna S. In vitro comparative SEM analysis of nano-hydroxyapatite toothpaste and diode laser: evaluation of efficacy of dentinal tubular occlusion. Journal of Stomatology. 2022;75(1):1-6. doi:10.5114/jos.2022.114033. APA Shamel, M., & El Banna, S. (2022). In vitro comparative SEM analysis of nano-hydroxyapatite toothpaste and diode laser: evaluation of efficacy of dentinal tubular occlusion. Journal of Stomatology, 75(1), 1-6. https://doi.org/10.5114/jos.2022.114033 Chicago Shamel, Mohamed, and Sara El Banna. 2022. "In vitro comparative SEM analysis of nano-hydroxyapatite toothpaste and diode laser: evaluation of efficacy of dentinal tubular occlusion". Journal of Stomatology 75 (1): 1-6. doi:10.5114/jos.2022.114033. Harvard Shamel, M., and El Banna, S. (2022). In vitro comparative SEM analysis of nano-hydroxyapatite toothpaste and diode laser: evaluation of efficacy of dentinal tubular occlusion. Journal of Stomatology, 75(1), pp.1-6. https://doi.org/10.5114/jos.2022.114033 MLA Shamel, Mohamed et al. "In vitro comparative SEM analysis of nano-hydroxyapatite toothpaste and diode laser: evaluation of efficacy of dentinal tubular occlusion." Journal of Stomatology, vol. 75, no. 1, 2022, pp. 1-6. doi:10.5114/jos.2022.114033. Vancouver Shamel M, El Banna S. In vitro comparative SEM analysis of nano-hydroxyapatite toothpaste and diode laser: evaluation of efficacy of dentinal tubular occlusion. Journal of Stomatology. 2022;75(1):1-6. doi:10.5114/jos.2022.114033.

Effect of commercially available nano-hydroxy apatite containing desensitizing mouthwash on dentinal tubular occlusion: an in vitro FESEM analysis.

Background and aimDentinal hypersensitivity is a significant clinical problem encountered in daily dental practice. The management of this condition requires a good understanding of the complexity of the problem, as well as the variety of treatments currently available. The treatment approaches can be either home care products or professionally applied desensitizing agents. The present in-vitro study was designed to investigate the dentinal tubule occluding ability of commercially available nano HA containing mouthwash using FESEM analysis.MethodsIn the present in vitro study, 15 human premolars and canines were taken and sectioned mesiodistally. A total of 30 dentinal samples were obtained. All the dentinal discs were etched with 6% citric acid for 2 minutes. The treated samples were washed thoroughly with distilled water for 30 seconds. Samples were divided in two groups of 15 each. The specimens in Group I were shaken vigorously in the Vitis Sensitive mouthwash for 2 min twice daily for 14 days. After this intervention samples were placed in distilled water. Group II specimens were immersed in distilled water. Samples were subjected to FESEM to analyze for tubular occlusion.ResultsIn group I nearly complete dentinal surface occlusion was present on the 7th and 14th day and precipitates were seen covering a large part of the dentinal surface. In group II no dentinal tubular occlusion was observed.ConclusionThe results of the present study support the ability of nHA containing Vitis sensitive mouthwash to occlude the dentinal tubules and thus it may demonstrate a significant reduction in dentinal hypersensitivity when used clinically.

Influence of nano-hydroxyapatite containing desensitizing toothpastes on the sealing ability of dentinal tubules and bonding performance of self-etch adhesives

ObjectivesTo evaluate the dentinal tubular occlusion of nano-hydroxyapatite (nHAp) containing desensitizing toothpastes and their influence on the resin-dentin bonding performance of two mild self-etch adhesives. Materials and methodsMid-coronal dentin specimens were prepared from obtained intact human third molars. They were immersed in 1% citric acid for 20 s to expose the dentinal tubules to simulate sensitive teeth and then randomly divided into four groups. The control group received no desensitizing treatment. Experimental groups were treated with two commercial nHAp containing desensitizing toothpastes (Biorepair and Dontodent) and an experimental pure nHAp paste respectively. Each group was further divided into two subgroups and bonded with either G-Bond or Clearfil S3 Bond. The micro-tensile bond strength was tested and failure mode distribution was analyzed. Moreover, the effect of desensitizers on dentinal tubular occlusion was observed by the field-emission scanning electron microscope (FESEM). Resin infiltration of the adhesives labeled by fluorescent Rhodamin B was evaluated under confocal laser scanning microscopy (CLSM). ResultsFESEM revealed that all the desensitizers noticeably occluded the dentinal tubules, and the extents were completer after application for 7 days. The majority of the occlusion still preserved even after acid challenge with cola or adhesive. CLSM demonstrated shorter resin tags were produced in the desensitized groups. When bonding with G-Bond, the pure nHAp group showed comparable bond strength to the control group, while Biorepair and Dontodent treatment decreased the bond strength. For groups bonded with Clearfil S3 Bond, all the desensitizers reduced the bond strengths compared to the control and no significant difference was found among the three groups. ConclusionNano-hydroxyapatite containing desensitizing toothpastes could occlude dentinal tubules effectively with a certain degree of acid resistance, which contributes to the relief of dentin hypersensitivity. While, the application of these nHAp desensitizers comprised the resin infiltration of G-Bond and Clearfil S3 Bond, resulting in decreased bond strengths of the resin-dentin bonding.

Synthesis and characterization of a new methacrylate monomer derived from the cashew nut shell liquid (CNSL) and its effect on dentinal tubular occlusion

ObjectiveThe aim of this study was to synthesize, to characterize and to evaluate the effects on tubular occlusion of new monomer derived from cashew nut shell liquid (CNSL), also studying the effects of acid challenge (AC) on dentin surfaces treated with desensitizers. MethodsThe intermediary cardanol-epoxy (CNE) was synthesized through epoxidation of CNSL, followed by synthesis of cardanol-methacrylate-epoxy (CNME) through methacryloyl chloride esterification. Products were purified through chromatography column and characterized by Fourier transform infrared spectrometry and nuclear magnetic resonance. Resinous dentin desensitizers were formulated containing either unsaturated cardanol (CNU), CNE or CNME. Dentin disks were divided into seven groups: SL — Smear-layer, EDTA — EDTA-treated only, GLUMA — Gluma Desensitizer, OCB — One Coat Bond, CNU — CNU desensitizer, CNE — CNE desensitizer and CNME — CNME desensitizer. Dentinal fluid rate (DFF) was obtained using a Flodec equipment and tubular occlusion employing a scanning electron microscope (SEM), before and after AC. Data of DFF were submitted to two-way ANOVA and Tukey’s test (p<0.05). ResultsGLUMA showed the lower reduction in DFF when compared to the other products, which were statistically similar. Even after AC, CNME presented the most homogenous and occluded surface, while CNE and CNU were partially removed, GLUMA was completely removed and OCB keep an occluded, but irregular surface. SignificanceCNME showed a great reduction of DFF and a homogenous occluded surface, suggesting that it may be a suitable and acid-resistant treatment option for dentine hypersensitivity.

Comparative scanning electron microscope analysis of diode laser and desensitizing toothpastes for evaluation of efficacy of dentinal tubular occlusion.

Background:The present study aims to evaluate the efficacy of diode laser alone and in combination with desensitizing toothpastes in occluding dentinal tubules (both partially occluded and completely occluded tubules) by scanning electron microscope (SEM).Materials and Methods:Fifty human teeth were extracted, cervical cavities were prepared and etched with 17% ethylenediaminetetraacetic acid, and smear layer was removed to expose the tubules. The teeth were divided into five groups: Group I – Application of NovaMin-formulated toothpaste, Group II – Application of Pro-Argin™-formulated toothpaste, Group III – Application of diode laser in noncontact mode, Group IV – NovaMin-formulated toothpaste followed by laser irradiation, and Group V – Pro-Argin™-formulated toothpaste followed by laser irradiation. After treatment, quantitative analysis of occluded dentinal tubules was done by SEM analysis.Results:The mean values of percentages of total occlusion of dentinal tubules in Groups I, II, III, IV, and V were 92.73% ± 1.38, 90.67% ± 1.86, 96.57% ± 0.64, 97.3% ± 0.68, and 96.9% ± 6.08, respectively. Addition of diode laser (Groups III, IV, and V) yielded a significant occlusion of the dentinal tubules when compared to desensitizing toothpastes alone (Groups I and II).Conclusion:Diode laser (Group III) has shown more efficacy in occluding dentinal tubules when compared with desensitizing toothpastes which was statistically significant (P < 0.05). Among the five groups, NovaMin + diode laser (Group IV) showed the highest percentage of occluded dentinal tubules.

Comparative Morphologic Evaluation and Occluding Effectiveness of Nd: YAG, CO2 and Diode Lasers on Exposed Human Dentinal Tubules: An Invitro SEM Study.

Dentinal hypersensitivity is one of the most common problem, encountered in dental practice but has least predictable treatment outcome. The advent of lasers in dentistry has provided an additional therapeutic option for treating dentinal hypersensitivity. Although various lasers have been tried over a period of time to treat dentinal hypersensitivity, but still the doubt persist as to which laser leads to maximum dentinal tubular occlusion and is most suitable with minimal hazardous effects. To compare the effects of Nd: YAG, CO2 and 810-nm diode lasers on width of exposed dentinal tubule orifices and to evaluate the morphologic changes on dentinal surface of human tooth after laser irradiation by scanning electron microscope (SEM). Forty root specimens were obtained from ten freshly extracted human premolars, which were randomly divided into four groups of ten each. Group I: control group treated with only saline, Group II: Nd:YAG laser, Group III: CO2 laser and Group IV: 810-nm diode laser. The specimens were examined using SEM. After calculating mean tubular diameter for each group, the values were compared statistically using parametric one-way ANOVA test and Turkey's post hoc multiple comparison test. All the three lased groups showed a highly statistical significant result with p-value of <0.001 as compared to non-lased group. On intergroup comparison within the lased groups, all the three groups showed statistically significant difference in the reduction of dentinal tubular diameter (p-value < 0.001). Nd: YAG laser was found to be most effective, followed by the CO2 laser and 810-nm diode laser was found to be least effective. The morphologic changes like craters, cracks and charring effect of the dentine were seen maximum by the use of CO2 laser.

Evaluation of dentinal tubule occlusion and depth of penetration of nano-hydroxyapatite derived from chicken eggshell powder with and without addition of sodium fluoride: An in vitro study.

Aim:This in vitro study evaluated the degree of dentinal tubule occlusion and depth of penetration of nano-hydroxyapatite (nHAp) derived from chicken eggshell powder with and without the addition of 2% sodium fluoride (NaF) using scanning electron microscope (SEM) and confocal laser scanning microscope (CLSM).Materials and Methods:nHAp was synthesized and characterized using X-ray diffraction and SEM-energy dispersive spectroscopy. Dentin discs were obtained from extracted teeth, pretreated with 17% ethylenediaminetetraacetic acid for 5 min and were divided into four groups based on the experimental agents as follows: Group 1: Untreated (control), Group 2: 2% NaF, Group 3: nHAp, Group 4: Combination of nHAp and 2% NaF. The treatment protocol was carried out for 7 days, after which the specimens were viewed under SEM and CLSM.Statistical Analysis Used:One-way ANOVA and Tukey's post hoc multiple comparison tests (P < 0.05).Results:All the experimental agents occluded the dentinal tubules, but to varying degrees and depths. Specimens treated with the combination of nHAp and 2% NaF showed complete dentinal tubular occlusion and significantly greater depth of penetration than those treated with nHAp and 2% NaF alone.Conclusion:The combination of nHAp and 2% NaF was the most effective in occluding dentinal tubules.

Effects of citric Acid and desensitizing agent application on nonfluorosed and fluorosed dentin: an in vitro sem study.

Fluorosis is one of the factors which bring about mineralisation changes in a dentinal structure leading to dentin. The purpose of the present study was to compare and evaluate the dentinal tubular changes in fluorosed and nonfluorosed teeth subsequent to the application of citric acid,strontium acetate based sodium fluoride (SAF) using scanning electron microscopy (SEM). Dentin specimens from healthy fluorosed and nonfluorosed teeth were included in the study. Each of them was grouped into acid treated and SAF treatment groups. Using SEM, the photomicrographs (3500x) of dentin specimens were evaluated. Results showed while there was a significant difference in tubular width of partial occlusion ≤ 25%, being more in fluorosed group compared to nonfluorosed group after application SAF. Application of desensitising agents demonstrated higher number of dentinal tubular occlusion and diameter reduction in nonfluorosed dentin compared to fluorosed dentin. Summary: Root biomodification and desensitising agent procedure brings in definite difference between fluorosed and non-fluorosed dentin specimens.

Comparative evaluation of a dentifrice containing calcium sodium phosphosilicate to a dentifrice containing potassium nitrate for dentinal hypersensitivity: A clinical study.

Background:Calcium sodium phosphosilicate is a recently introduced desensitizing agent which acts by occluding the dentinal tubules and also resists acid decalcification. This study was designed to assess the efficacy of a new toothpaste containing 5% calcium sodium phosphosilicate for the treatment of dentinal hypersensitivity and also compare it with 5% potassium nitrate.Materials and Methods:Sixty patients with the chief complaint of dentinal hypersensitivity were enrolled and randomly divided into two groups. The visual analog scale (VAS) scores were taken for water and air stimuli at baseline, 3 weeks after usage of the respective toothpaste, and 3 weeks after discontinuation of the respective toothpaste.Results:Both the groups showed reduction in hypersensitivity scores at 3 weeks and 6 weeks for air stimulus and cold water. The calcium sodium phosphosilicate group, however, showed significantly reduction in hypersensitivity compared to the potassium nitrate group at any time point for both measures of hypersensitivity.Conclusion:The 5% calcium sodium phosphosilicate group showed immense reduction in dentinal hypersensitivity symptoms. The 5% calcium sodium phosphosilicate showed prolonged effects even after discontinuation as compared to 5% potassium nitrate, due to its dentinal tubular occlusion property.

In-vitro assessment of effect of a hydroxyapatite containing desensitizing agent on dentinal ubule occlusion

Aim and Objectives: Dentinal hypersensitivity (DH) is a common clinical condition usually associated with exposed dentinal surfaces. The present study evaluated the influence of topical application of hydroxyapatite containing desensitizing agent (Remin Pro) on dentinal tubule occlusion. Materials and Methods: A total of 22 dentin discs obtained from 11 anterior teeth were divided into two groups. Test group (Remin Pro) and control group (distilled water). The specimens treated with 17% ethylene diamine tetraacetic acid gel prior to the application of test agents followed by rinsing and application of test agents for 5 min. After rinsing, 5% Evans blue dye was applied on both the specimens. The specimens were observed under light microscope. A quantitative analysis of tubular occlusion was done by counting the number of dentinal tubules/1000 μm 2 , diameter of dentinal tubules (μm), and closed tubular area (μm 2 ). Percentage of tubular occlusion was calculated in both the groups. Results: Mean number of occluded dentinal tubules in Group A was 78.01% whereas in case of Group B it was 4.97%. With a higher percentage of tubular occlusion, the diameter and number of dentinal tubules decreased and closed tubular area of each tubule increased. Conclusion: The desensitizing agent produced significant greater dentinal tubular occlusion as compared to the control group. Clinical implications: Though in-vitro studies provide evidence for immediate dentine hypersensitivity treatment, further well-designed multicenter prospective long-term clinical trials with scanning electron microscopic evaluation are needed to find the gold standard treatment of DH.

In vivo, morphological and clinical effects of a desensitizing agent

Objectives: This study evaluated the in vivo effectiveness of Universal Dentin Sealant (UDS), a new resin-based material, as dentinal desensitizing agent on dentin morphology and clinical symptoms. Materials and methods: Thirty premolars, exhibiting non-carious cervical lesions, and scheduled for extraction for periodontal reasons, were selected for the ultrastructural study. These samples were randomly divided into three groups ( n = 10): group 1, brushing with UDS; group 2, brushing with Flor-Opal ® Varnish (FOV); and group 3, untreated control. After 7 days, teeth were extracted and samples processed for SEM and TEM comparative observations. The in vivo study was carried out on 90 teeth with non-carious cervical lesions. The assessment method used to quantify sensitivity was the cold air syringe, recorded using the visual analogue scale (VAS), prior to treatment (baseline) and after 7 days. Teeth were randomly assigned to three groups ( n = 30): group 1, UDS; group 2, FOV; and group 3, untreated control. Analysis was based on the Student's t-test for paired data, with a 5% significance level. Results: The ultrastructure of UDS/dentin interface was characterized by a superficial porous layer of spherical clusters immersed in a loose matrix that fully covered the superficial dentin. A poorly crystalline aspect of peritubular and intertubular fibrils with sealed tubular orifices was observed. The FOV/dentin interface showed an irregular layer of precipitates with partial exposure of the dentin surface. The presence of intratubular crystals partially occluding the tubular orifices and densely mineralized peritubular fibrils was also noted. Untreated control dentin showed a superficial thin layer of smear with porous plugs within the tubular orifices. Comparing clinical results, the statistical analysis revealed significant differences between both the tested materials ( p p > 0.05) in term of the periods of examination. Conclusions: The application of UDS resulted in effective and stable dentinal tubular occlusion, leading to a statistically significant decrease in clinical discomfort of particular relevance to cases of dentinal hypersensitivity.