1
|
Rodriguez-Sendra J, Torres I, Jimenez N, Sauro S, Camarena F. Ultrasonic Monitoring of Dentin Demineralization. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2021; 68:570-578. [PMID: 32776879 DOI: 10.1109/tuffc.2020.3015668] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Demineralization is a process of loss of minerals in the dental hard tissue that affects seriously the health of the patients, as it diminishes the tooth resistance, generating chewing problems by altering the occlusal structure, hypersensitivity, and pulpal problems. Demineralization can be produced by pathological processes as erosion or caries, or by surgical processes as etching. Due to the complexity of natural demineralization processes, it is mandatory to provide quantitative and standardized tests to allow their study in controlled laboratory conditions. Ultrasonic techniques are suitable for this purpose as they are nondestructive, quick, and provide localized mechanical information about the tissue, which is related with its degree of demineralization. In the present work, we evaluate the complete process of demineralization of the human dentin under controlled laboratory conditions using a pulse-echo ultrasonic technique. Up to 15 human dentin teeth have been demineralized with phosphoric acid at 10%. The time-of-flight measurements using the pulse-echo system allows to obtain the speed of sound in healthy (3415 m/s) and demineralized dentin tissue (1710 m/s), as well as to characterize the dynamical process of the acid penetration, which generates well-defined boundaries between two media (demineralized and mineralized dentin), showing very different mechanical properties. These boundaries advance in depth at an initial rate of [Formula: see text]/min, decelerating at -9.3 nm/min2 until the whole demineralization of the sample is achieved. In addition, the technique allows to measure the relevance of the demineralization produced by the acid residues inside the tooth once it has been removed from the acidic solution. Beyond the assessment of artificial demineralization lesions under laboratory conditions, as demonstrated in this article, the proposed technique opens new approaches to the assessment of demineralization caused by natural caries in vivo.
Collapse
|
2
|
In Vitro Study on the Effect of a New Bioactive Desensitizer on Dentin Tubule Sealing and Bonding. J Funct Biomater 2020; 11:jfb11020038. [PMID: 32498468 PMCID: PMC7353572 DOI: 10.3390/jfb11020038] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Revised: 05/24/2020] [Accepted: 05/25/2020] [Indexed: 11/16/2022] Open
Abstract
Bioactive mineral-based dentin desensitizers that can quickly and effectively seal dentinal tubules and promote dentin mineralization are desired. This in vitro study evaluated a novel nanohydroxyapatite-based desensitizer, Predicta (PBD, Parkell), and its effect on bond strength of dental adhesives. Human dentin discs (2-mm thick) were subjected to 0.5 M EDTA to remove the smear layer and expose tubules, treated with PBD, and processed for surface and cross-sectional SEM examination before and after immersion in simulated body fluid (SBF) for four weeks (ISO 23317-2014). The effects of two dental desensitizers on the microshear bond strength of a universal adhesive and a two-step self-etch system were compared. SEM showed coverage and penetration of nanoparticles in wide tubules on the PBD-treated dentin at the baseline. After four weeks in SBF, untreated dentin showed amorphous mineral deposits while PBD-treated dentin disclosed a highly mineralized structure integrated with dentin. Desensitizers significantly reduced microshear bond strength test (MSBS) of adhesives by 15-20% on average, depending on the bonding protocol. In conclusion, PBD demonstrated effective immediate tubules sealing capability and promoted mineral crystal growth over dentin and into the tubules during SBF-storage. For bonding to desensitizer-treated dentin, a two-step self-etching adhesive or universal bond with phosphoric acid pretreatment are recommended.
Collapse
|
3
|
Takamizawa T, Tsujimoto A, Ishii R, Ujiie M, Kawazu M, Hidari T, Suzuki T, Miyazaki M. Laboratory evaluation of dentin tubule occlusion after use of dentifrices containing stannous fluoride. J Oral Sci 2019; 61:276-283. [PMID: 31217376 DOI: 10.2334/josnusd.18-0176] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
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.
Collapse
Affiliation(s)
- Toshiki Takamizawa
- Department of Operative Dentistry, Nihon University School of Dentistry.,Dental Research Center, Division of Biomaterial Science, Nihon University School of Dentistry
| | - Akimasa Tsujimoto
- Department of Operative Dentistry, Nihon University School of Dentistry.,Dental Research Center, Division of Biomaterial Science, Nihon University School of Dentistry
| | - Ryo Ishii
- Department of Operative Dentistry, Nihon University School of Dentistry
| | - Maho Ujiie
- Department of Operative Dentistry, Nihon University School of Dentistry
| | - Mami Kawazu
- Department of Operative Dentistry, Nihon University School of Dentistry
| | - Toshie Hidari
- Department of Operative Dentistry, Nihon University School of Dentistry
| | - Takayuki Suzuki
- Department of Operative Dentistry, Nihon University School of Dentistry
| | - Masashi Miyazaki
- Department of Operative Dentistry, Nihon University School of Dentistry.,Dental Research Center, Division of Biomaterial Science, Nihon University School of Dentistry
| |
Collapse
|
4
|
Kyaw KY, Otsuki M, Hiraishi N, Segarra MS, Tagami J. Effect of application of desensitizers before bleaching on change of tooth shade. Dent Mater J 2019; 38:790-797. [PMID: 31434830 DOI: 10.4012/dmj.2018-129] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The aim of this in vitro study was to evaluate the effects of desensitizer pre-treatment on in-office bleaching using an artificial discoloration tooth model. The stained specimens were divided into four groups (n=10); without application (Control group), Shield Force plus (SF group), UltraEz (UE group) and Teeth Mate AP paste (TM group) applied before bleaching. Each group was bleached by an in-office bleaching agent. The CIE L*a*b* values were measured by a colorimeter before and after ten consecutive bleaching treatments and the color difference (∆E) was calculated. There was no statistical difference among ∆E values of Control, UE, and TM groups (p>0.05). There was a significant difference between SF and Control groups (p<0.001). It was concluded that application of TM and UE did not affect the change of tooth shade while SF application impeded the bleaching effect.
Collapse
Affiliation(s)
- Khin Yupar Kyaw
- Cariology and Operative Dentistry, Department of Restorative Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
| | - Masayuki Otsuki
- Cariology and Operative Dentistry, Department of Restorative Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
| | - Noriko Hiraishi
- Cariology and Operative Dentistry, Department of Restorative Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
| | - Michelle Sunico Segarra
- Cariology and Operative Dentistry, Department of Restorative Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University.,Section of Operative Dentistry, College of Dentistry, University of the Philippines Manila Pedro Gil St
| | - Junji Tagami
- Cariology and Operative Dentistry, Department of Restorative Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
| |
Collapse
|
5
|
Kanehira M, Ishihata H, Araki Y, Takahashi H, Sasaki K, Finger WJ. Effect of artificial saliva on permeability of dentin treated with phosphate containing desensitizer measured by digital flow meter. Dent Mater J 2019; 38:963-969. [PMID: 31434831 DOI: 10.4012/dmj.2018-134] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The aim of this study was to investigate the effects of artificial saliva on permeability measured using a highly sensitive digital flow meter of dentin discs treated with a phosphate containing desensitizer compound (Teethmate desensitizer; TD). Four random groups (n=10) were treated either with TD or distilled water (DW), then stored in artificial saliva (AS) or DW for 1 day, 1 week and 1 month. Flow rates under 2 kPa pressure were calculated as percentage reduction (PR%) from the baseline. The PR% of TD/AS group was significantly lower after 1 day and 1 week, but the PR%s of 1 month groups among TD/AS, TD/DW and DW/AS were not significantly different. The SEM photograph of TD/AS group displayed that the dentin surface was densely covered with mineral deposits. Ca and phosphate ions from the artificial saliva could penetrate into the tubules and precipitate as hydroxyapatite, resulting in the reduction in permeability.
Collapse
Affiliation(s)
- Masafumi Kanehira
- Division of Operative Dentistry, Department of Restorative Dentistry, Tohoku University Graduate School of Dentistry
| | - Hiroshi Ishihata
- Division of Periodontology and Endodontology, Department of Oral Biology, Tohoku University Graduate School of Dentistry
| | - Yasuyuki Araki
- Functional Photochemistry and Chemical Biology, Division of Organic- and Bio-Materials Research, Institute of Multidisciplinary Research for Advanced Materials, Tohoku University
| | - Hidekazu Takahashi
- Department of Oral Biomaterials Engineering, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
| | - Keiichi Sasaki
- Division of Advanced Prosthetic Dentistry, Department of Oral Function and Morphology, Tohoku University Graduate School of Dentistry
| | - Werner J Finger
- Liaison Center for Innovative Dentistry, Tohoku University Graduate School of Dentistry
| |
Collapse
|
6
|
Zhang L, Sun H, Yu J, Yang H, Song F, Huang C. Application of electrophoretic deposition to occlude dentinal tubules in vitro. J Dent 2018; 71:43-48. [PMID: 29391182 DOI: 10.1016/j.jdent.2018.01.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Revised: 01/21/2018] [Accepted: 01/26/2018] [Indexed: 11/18/2022] Open
Abstract
OBJECTIVES This study aims to apply electrophoretic deposition (EPD) for occlusion of dentinal tubules in vitro and investigate its effect on tubule occlusion and shear bond strength (SBS). METHODS Charged mesoporous silica nanoparticles (MSNs) were synthesized and characterized through field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), dynamic light scattering (DLS), and Fourier transform infrared (FT-IR) spectroscopy analyses. Thirty-nine sensitive dentin specimens were modeled and assigned randomly to three groups with different treatments (n = 13 each): group 1, immersion in the MSN suspension; and groups 2 and 3, anodic EPD with the specimen on the negative and positive electrode respectively. The effect of dentinal tubule occlusion was evaluated by dentin permeability test (n = 10 each) and FESEM examination (n = 3 each). Moreover, 18 specimens were grouped (n = 6 each) and treated in the same method. A resin stick was bonded onto each of the specimen using a self-etch adhesive (single bond universal) for SBS testing. RESULTS Negatively-charged MSNs were synthesized and characterized as small and well-dispersed particles. After the EPD treatment (group 3), the dentinal tubules were effectively occluded by MSNs, which infiltrated into the tubules at a depth of approximately 7-8 μm and tightly associated with the tubular inwalls. SBS was not significantly different among the three groups (P > 0.05). CONCLUSIONS Synthesized MSNs were deposited into dentinal tubules by EPD treatment without compromising dentin bond strength. CLINICAL SIGNIFICANCE Application of EPD is a new approach for occlusion of dentinal tubules and exhibits potential in the study of dentin hypersensitivity.
Collapse
Affiliation(s)
- Lu Zhang
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan 430079, China
| | - Hualing Sun
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan 430079, China
| | - Jian Yu
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan 430079, China
| | - Hongye Yang
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan 430079, China
| | - Fangfang Song
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan 430079, China
| | - Cui Huang
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan 430079, China.
| |
Collapse
|
7
|
Nakata T, Kitasako Y, Sadr A, Nakashima S, Tagami J. Effect of a calcium phosphate and fluoride paste on prevention of enamel demineralization. Dent Mater J 2017; 37:65-70. [PMID: 28835599 DOI: 10.4012/dmj.2016-347] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
This study aimed to examine the anti-demineralization capacities of (a) tetracalcium phosphate (TTCP) and dicalcium phosphate anhydrous (DCPA) and 950 ppm fluoride paste, (b) casein phosphopeptide amorphous calcium phosphate paste and (c) 950 ppm fluoride solution using optical coherence tomography (OCT). Enamel blocks were cut from the bovine incisors and treated using one of the above-mentioned three materials or deionized water as control (n=10). All samples were subjected to a demineralization gel for 1 h followed by a remineralization solution for 23 h. This experimental cycle was repeated for 28 days. The specimens were imaged using OCT at baseline and at four stages and measured lesion depth using image analysis software (ImageJ). Repeated measures ANOVA revealed that demineralization time, material and their interaction significantly affected the optical lesion depth (p<0.001). TTCP and DCPA and 950 ppm fluoride paste and 950 ppm fluoride solution showed significantly lower lesion progress compare to other groups (p<0.05).
Collapse
Affiliation(s)
- Takuya Nakata
- Cariology and Operative Dentistry, Department of Restorative Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
| | - Yuichi Kitasako
- Cariology and Operative Dentistry, Department of Restorative Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University.,Dental Clinic, Ministry of Foreign Affairs
| | - Alireza Sadr
- Cariology and Operative Dentistry, Department of Restorative Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University.,Biomimetics Biomaterials Biophotonics Biomechanics & Technology Laboratory, Department of Restorative Dentistry, University of Washington School of Dentistry
| | - Syozi Nakashima
- Cariology and Operative Dentistry, Department of Restorative Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
| | - Junji Tagami
- Cariology and Operative Dentistry, Department of Restorative Sciences, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University
| |
Collapse
|
8
|
Ishihata H, Kanehira M, Finger WJ, Takahashi H, Tomita M, Sasaki K. Effect of two desensitizing agents on dentin permeability in vitro. J Appl Oral Sci 2017; 25:34-41. [PMID: 28198974 PMCID: PMC5289398 DOI: 10.1590/1678-77572016-0228] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Accepted: 09/15/2016] [Indexed: 11/24/2022] Open
Abstract
Objective The aim of this in vitro study was to investigate the effect of two desensitizing agents and water on hydraulic conductance in human dentin. Material and Methods GLUMA Desensitizer PowerGel (GLU) contains glutaraldehyde (GA) and 2-hydroxyethyl methacrylate (HEMA), and Teethmate Desensitizer (TD) is a powder comprising tetracalcium phosphate (TTCP) and dicalcium phosphate anhydrous (DCPA) that is mixed with water. Deionized water was used as a negative control (CTR). Thirty discs with a thickness of 1.2 mm were cut from the coronal dentin of the third molars and cleaned with 0.5 M EDTA (pH 7.4). After being mounted in a split-chamber device, the discs were pressurized with water at 1 kPa and 3 kPa in order to measure flow rates with a highly sensitive micro-flow sensor and to calculate hydraulic conductance as a baseline value (BL). Following the application of GLU, TD, and CTR (n=10), hydraulic conductance was remeasured with intermittent storage in water after 15 min, 1 d, 1 w, and 1 m. Reduction in permeability (PR%) was calculated from hydraulic conductance. Data were statistically analyzed using nonparametric methods (α<0.05). Representative discs were inspected by SEM. Results PR% for GLU and TD were 30-50% 15 min and 1 m after their application. Post hoc tests indicated that PR% of CTR was significantly greater than those of GLU and TD at all time points tested. The PR% of GLU and TD were not significantly different. SEM examinations showed noncollapsed collagen meshes at the tubular entrances after GLU, and crystalline precipitates occluding the tubular orifices after TD, whereas CTR specimens showed typical patterns of etched dentin. Conclusions The present study on hydraulic conductance in dentin discs treated with two chemically different desensitizing agents and water as a control demonstrated that both products may be characterized as effective.
Collapse
Affiliation(s)
- Hiroshi Ishihata
- Tohoku University, Graduate School of Dentistry, Division of Periodontology and Endodontology, Department of Oral Biology, Sendai, Japan
| | - Masafumi Kanehira
- Tohoku University, Graduate School of Dentistry, Division of Operative Dentistry, Department of Restorative Dentistry, Sendai, Japan
| | - Werner J Finger
- Tohoku University, Graduate School of Dentistry, Liaison Center for Innovative Dentistry, Sendai, Japan
| | - Hidekazu Takahashi
- Tokyo Medical and Dental University, Graduate School of Medical and Dental Sciences, Oral Biomaterials Engineering, Tokyo, Japan
| | - Makoto Tomita
- Tokyo Medical and Dental University, Clinical Research Center, Tokyo, Japan
| | - Keiichi Sasaki
- Tohoku University, Graduate School of Dentistry, Division of Advanced Prosthetic Dentistry, Department of Oral Function and Morphology, Sendai, Japan
| |
Collapse
|
9
|
Miyazaki M, Tsujimoto A, Tsubota K, Takamizawa T, Kurokawa H, Platt JA. Important compositional characteristics in the clinical use of adhesive systems. J Oral Sci 2016; 56:1-9. [PMID: 24739701 DOI: 10.2334/josnusd.56.1] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
Improvements in dentin bonding systems have influenced modern restorative dentistry. The desire for minimal invasiveness has resulted in more-conservative cavity design, which basically relies on the effectiveness of current dentin bonding systems. Interaction of adhesives with enamel and dentin is based on two systems, commonly described as etch-and-rinse and self-etch. Priming and bonding agents can be separate or combined, resulting in two- or three-step systems for etch-and-rinse adhesives and one- or two-step systems for self-etch adhesives. Self-etch systems use acidic functional monomers that simultaneously demineralize and impregnate tooth structures. Etch-and-rinse and self-etch systems have advantages and disadvantages, which are primarily related to the simplified bonding procedures required under clinical conditions. Knowledge of the composition, characteristics, and mechanisms of adhesion for each adhesive system is critical in selecting the ideal adhesive materials for clinical use.
Collapse
Affiliation(s)
- Masashi Miyazaki
- Department of Operative Dentistry, Nihon University School of Dentistry
| | | | | | | | | | | |
Collapse
|