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1.
Am J Dent ; 34(2): 80-86, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33940664

RESUMO

PURPOSE: To evaluate and compare the effect on micro-tensile bond strength (µTBS) of a double layer application of three universal adhesives applied in self-etch mode to proximal dentin/cementum gingival margins of class II direct composite restorations, immediately and after 12 months water storage. METHODS: 66 molars with compound class II cavities, with gingival margin 1 mm below CEJ, were divided into three groups according to the universal adhesive used. The adhesives evaluated included All-Bond Universal (AB), Single Bond Universal (SB), and Prime&Bond Elect (PB). The groups were further subdivided according to adhesive application technique, either single layer or double layer application. All teeth were restored with the same nanofilled resin composite. µTBS were examined at a crosshead speed of 0.5 mm/minute after 24 hours or 12 months water storage. Fracture mode was assessed under stereomicroscope. Data were analyzed by two-way analysis of variance (ANOVA) followed by Tukey's post hoc test (P< 0.05). RESULTS: The double layer application µTBS values were significantly higher than single layer application in all groups. Regardless of the type of adhesive or application technique, all subgroups showed significantly decreased bond strength after aging. There were significant lower µTBS values for AB adhesive compared with the other two adhesives that demonstrated no significant differences between them. The double layer application technique was effective in enhancing µTBS values of all tested adhesives bonded to proximal dentin/cementum gingival margins compared to single layer application. Regardless of application technique, all tested adhesives were incapable of defying long-term water aging. CLINICAL SIGNIFICANCE: The double layer application technique may be recommended to enhance the bonding durability of universal adhesives to face challenges in bonding to dentin-cementum cervical margins.


Assuntos
Colagem Dentária , Adesivos Dentinários , Cimentos Dentários , Cemento Dentário , Dentina , Teste de Materiais , Cimentos de Resina
2.
Am J Dent ; 34(2): 105-109, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33940669

RESUMO

PURPOSE: To evaluate the chemical composition and morphological properties of eroded dentin after biomodification with phosphorylated chitosan (P-Chi) and carbodiimide (EDC). METHODS: 42 bovine dentin specimens were used; 21 of these specimens were subjected to erosive challenge with 0.3% citric acid (pH = 3.2) for 2 hours. The specimens were randomly divided into six groups according to dentin substrate (sound or eroded) and biomodification [with 2.5% P-Chi, with 0.5 mol/L EDC, or no biomodification (control)]. The specimens were analyzed by Fourier-transform infrared spectroscopy (FTIR, n= 5, in triplicate) and atomic force microscopy (AFM, n= 2) to verify the phosphate, carbonate, and organic matrix absorption peaks and to investigate surface morphology, respectively. The data were analyzed with Origin 6.0. RESULTS: Dentin erosion reduced the intensity of the phosphate (1,100 cm⁻¹) and carbonate (872 cm⁻¹) related bands, which evidenced demineralization. Eroded dentin consisted of a more irregular surface containing slightly more open tubules. Modification with P-Chi removed intertubular dentin, which was compatible with surface demineralization; however, this modification obliterated dentin tubules. EDC did not promote demineralization. Biomodified dentin had a more irregular surface, irrespective of substrate type. CLINICAL SIGNIFICANCE: Eroded dentin demineralization promoted by biomodification with 2.5% phosphorylated chitosan (P-Chi) is a promising indicator for further studies and highlights the dentin intrinsic characteristics. From the point of view of dentin surface chemical analysis, more studies with P-Chi should be conducted to achieve greater interactions with surfaces and to improve the adhesive interface.


Assuntos
Carbodi-Imidas , Quitosana , Animais , Bovinos , Cimentos Dentários , Dentina
3.
J Clin Pediatr Dent ; 45(2): 98-103, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33951172

RESUMO

OBJECTIVES: To determine different combinations of marginal ridge shape (MRS) and contact extents in nature of the contact between primary molars and its correlation with the presence of carious lesions on radiographic examination of approximal surfaces. STUDY DESIGN: Retrospective study of 347 clinical records, including photographs and bitewing radiographs, were assessed for intact MRS and caries extent. The carious lesions were scored (0-5, Mejàre scoring system) radiographically and correlated to the intact MRS on clinical photographs, and strength of associations quantified using logistic regression analysis and chi-square tests. RESULTS: Primary molars, 848(contact extent), and 757(MRS) were analyzed. Combination of straight-convex(35.4%) MRS was more common (p<0.001). None of the approximal surfaces were caries-free for straight and straight MRS with 36.4% of both approximal surfaces exhibiting caries in enamel, and 38.2% of one approximal surface exhibiting caries in dentin. Approximately 90% of the primary molars with substantial contacts exhibited carious lesions in the enamel and 80% with light contacts exhibited carious lesions in the dentin (p<0.001). CONCLUSION: Six different combinations of intact MRS were identified. Combination of concave-convex shapes exhibited caries extending into dentin. Substantial and/or light contacts between primary molars showed higher caries experience in the approximal surfaces.


Assuntos
Suscetibilidade à Cárie Dentária , Cárie Dentária , Cárie Dentária/diagnóstico por imagem , Dentina , Humanos , Dente Molar/diagnóstico por imagem , Radiografia Interproximal , Estudos Retrospectivos
4.
Swiss Dent J ; 131(5): 425-430, 2021 May 10.
Artigo em Alemão | MEDLINE | ID: mdl-33952268

RESUMO

Autologous dentin as a bone substitute can be used in regenerative dentistry. Extracted teeth are not discarded but recycled and used in block or particulate form for lateral ridge augmentation before implant insertion. Due to the growth factors contained in the dentin and the autologous origin, a stable and good osseointegration of the augmentation material can be expected. This case report demonstrates how the dentin of an autologous wisdom tooth is used for lateral ridge augmentation in area 15 in a 30-year old female patient. The patient was successfully rehabilitated with an implant afterwards. Even though the indication range is limited due to the availability of dentin and the size of the defect, the procedure represents a promising and comparatively minimally invasive autologous augmentation procedure to expand the oral surgical field in regenerative dentistry.


Assuntos
Aumento do Rebordo Alveolar , Dente Serotino , Adulto , Transplante Ósseo , Implantação Dentária Endo-Óssea , Dentina , Feminino , Humanos , Dente Serotino/diagnóstico por imagem , Dente Serotino/cirurgia
5.
Br Dent J ; 230(7): 386-387, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33837313
6.
Artigo em Inglês | MEDLINE | ID: mdl-33808616

RESUMO

In the literature, autogenous dentin is considered a possible alternative to bone substitute materials and autologous bone for certain indications. The aim of this proof-of-concept study was to use autogenous dentin for lateral ridge augmentation. In the present retrospective study, autogenous dentin slices were obtained from teeth and used for the reconstruction of lateral ridge defects (tooth-shell technique (TST): 28 patients (15 females, 13 males) with 34 regions and 38 implants). The bone-shell technique (BST) according to Khoury (31 patients (16 females, 15 males) with 32 regions and 41 implants) on autogenous bone served as the control. Implants were placed simultaneously in both cases. Follow-up was made 3 months after implantation. Target parameters during this period were clinical complications, horizontal hard tissue loss, osseointegration, and integrity of the buccal lamella. The prosthetic restoration with a fixed denture was carried out after 5 months. The total observation period was 5 months. A total of seven complications occurred. Of these, three implants were affected by wound dehiscences (TST: 1, BST: 2) and four by inflammations (TST: 0, BST: 4). There were no significant differences between the two groups in terms of the total number of complications. One implant with TST exhibited a horizontal hard tissue loss of 1 mm and one with BST of 0.5 mm. Other implants were not affected by hard tissue loss. There were no significant differences between the two groups. Integrity of the buccal lamella was preserved in all implants. All implants were completely osseointegrated in TST and BST. All implants could be prosthetically restored with a fixed denture 5 months after augmentation. TST showed results comparable to those of the BST. Dentin can therefore serve as an alternative material to avoid bone harvesting procedures and thus reduce postoperative discomfort of patients.


Assuntos
Aumento do Rebordo Alveolar , Substitutos Ósseos , Transplante Ósseo , Dentina , Feminino , Seguimentos , Humanos , Masculino , Estudos Retrospectivos
7.
Oper Dent ; 46(1): 75-86, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33882135

RESUMO

CLINICAL RELEVANCE: Post and core crowns and endocrowns perform similarly on fracture strength, but endocrowns have more repairable fractures.


Assuntos
Incisivo , Técnica para Retentor Intrarradicular , Coroas , Cimentos Dentários , Falha de Restauração Dentária , Análise do Estresse Dentário , Dentina
8.
Oper Dent ; 46(1): E1-E10, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33882142

RESUMO

CLINICAL RELEVANCE: Carious and eroded dentin represent clinical challenges. The use of a universal bonding system, in a self-etching mode, associated with chlorhexidine (CHX) seems to not improve its longevity. This may be attributed to the competition for calcium between the bonding agent functional monomer and CHX.


Assuntos
Clorexidina , Colagem Dentária , Cimentos Dentários , Dentina , Adesivos Dentinários , Teste de Materiais , Cimentos de Resina , Resistência à Tração
9.
Pol Merkur Lekarski ; 49(290): 153-157, 2021 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-33895765

RESUMO

The greatest challenge of modern implantology is the loss of bone tissue in esthetic region of maxilla and mandible. Significant bone changes caused for example by cysts, unerupted teeth or traumatic extraction often provoke bilateral or trilateral bone defects. Thanks to the possibility of applying demineralized dentin and dentin blocks gained from extracted teeth of the patient, it is possible to successfully regenerate bone tissue especially in the esthetic zone. AIM: The aim of the study was to present a case of a patient who underwent bone augmentation for implantation. In addition, a review of the literature illustrating the effectiveness of autogenous bone graft material derived from ground teeth in augmentation procedures was performed. A CASE REPORT: The paper presents a case of a 26-year-old man in whom bone defect was augmented with material derived from dentin blocks and partially demineralized dentin processed in the BonMaker device after extraction of the root of tooth 11. A systematic review of literature was conducted analyzing articles published between 1975 and 2020. From 80 articles, 25 were selected for this study. CONCLUSIONS: The presented case and the systematic review of literature indicate that tooth-derived bone graft material prepared from extraction can effectively restore alveolar bone defect. The results we get so far are very satisfying. Further studies should be performed to confirm the osteogenic effects and safety use of this tooth based graft material.


Assuntos
Regeneração Óssea , Dentina , Adulto , Humanos , Masculino , Mandíbula , Extração Dentária/efeitos adversos
10.
Gen Dent ; 69(3): 37-41, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33908876

RESUMO

This in vitro study aimed to evaluate the influence of endodontic irrigation solutions and resin sealing of the dentin surfaces of the cavity before irrigation on the fracture strength (FS) of maxillary premolars. Seventy-two human maxillary premolars were randomly assigned to 6 groups (n = 12). Group 1 consisted of intact teeth that served as negative controls. In groups 2 to 6, root canal treatment was performed after mesio-occlusal preparation. In group 6, the dentin surfaces of the mesio-occlusal cavity were sealed with a self-adhesive flowable composite resin before instrumentation and irrigation of the canal. The volume and contact time of the irrigation solutions used during endodontic treatment of groups 2, 4, 5, and 6 were standardized as follows: 2 mL of 5.25% sodium hypochlorite (NaOCl) for 1 minute after each file, 5 mL of 17% ethylenediaminetetraacetic acid (EDTA) for 3 minutes after instrumentation was completed, and 5 mL of 5.25% NaOCl for 1 minute as the final irrigation. In group 3, the irrigation solution was normal saline solution only. After root canal obturation, in group 2, the cavities were left unrestored as a positive control. In groups 3 (saline-rinsed), 4 (conventionally restored), and 6 (presealed), the restorations were carried out with an etch-and-rinse adhesive and composite resin immediately after root canal obturations. In group 5 (delay-restored), the restorations were carried out with an etch-and-rinse adhesive and composite resin after a 1-week delay. After thermomechanical cycling, the teeth were subjected to FS testing under continuous compressive force. Data were analyzed with 1-way analysis of variance and Tukey tests. The unrestored group, which demonstrated the lowest FS, did not differ significantly from the conventionally restored group; the FS of both groups was significantly lower than that in the other groups (P ≤ 0.001). The presealed group exhibited the highest FS (P ≤ 0.02). The FS values of the saline and delay-restored groups were statistically comparable. In the present study, NaOCl/EDTA irrigation had an adverse effect on the FS. Presealing of the dentin surfaces of the cavity with self-adhesive flowable composite resin significantly increased the FS of aged composite resin-restored premolars.


Assuntos
Restauração Dentária Permanente , Fraturas dos Dentes , Idoso , Dente Pré-Molar , Resinas Compostas , Análise do Estresse Dentário , Dentina , Resistência à Flexão , Humanos , Teste de Materiais , Fraturas dos Dentes/prevenção & controle
11.
J Adhes Dent ; 23(2): 159-165, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33825429

RESUMO

PURPOSE: To evaluate the effect of inclusion of two dimethyl sulfoxide (DMSO) concentrations in simplified etch-and-rinse adhesives on dentin bonding durability after three years of water storage. MATERIALS AND METHODS: Forty-two caries-free third molars were divided into six experimental groups (n = 7) according to the following factors: 1) adhesive (Adper Single Bond 2 [SB], 3M Oral Care; Prime&Bond 2.1 [PB], Dentsply Sirona); 2) concentration of DMSO (control group: 0.0% DMSO; addition of 0.2% DMSO [0.2] and 2% DMSO [2.0]). After completing restoration, specimens were stored in water (37°C) for 24 h, sectioned into adhesive-dentin sticks (0.8 mm2), tested for microtensile bond strength (µTBS) at 0.5 mm/min, and examined for nanoleakage (NL) using SEM immediately thereafter or after three years of water storage. Data were subjected to a three-way repeated-measures ANOVA and Tukey's test (α = 0.05) for each property evaluated. RESULTS: After three years of water storage, for both adhesives, the incorporation of 2% DMSO maintained the µTBS when compared to immediate µTBS (p > 0.05). In general, SB resulted in a statistically significantly higher mean of µTBS compared to PB, independent of the DMSO concentration after water storage (p < 0.05). Furthermore, the amount of NL was lower and practically limited to the hybrid layer given the concentrations of 0.2% and 2% DMSO for both tested adhesives after three years. CONCLUSION: The incorporation of DMSO in simplified etch-and-rinse adhesives maintains the long-term stability of the dentin bond.


Assuntos
Colagem Dentária , Adesivos Dentinários , Dentina , Dimetil Sulfóxido , Teste de Materiais , Cimentos de Resina , Resistência à Tração , Água
12.
J Adhes Dent ; 23(2): 167-175, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33825430

RESUMO

PURPOSE: To investigate the effects of root canal irrigants, dentin surface treatment, and timing of the restoration on the microtensile bond strength (µTBS) of a universal adhesive to deep coronal dentin. MATERIALS AND METHODS: Ninety (90) intact molars were grouped according to the irrigation protocol: group 0 (saline, control group); group 1: 5.25% sodium hypochlorite (NaOCl), 17% ethylenediaminetetraacetic acid (EDTA) followed by 5.25% NaOCl; group 2: 18% etidronic acid (HEDP) + 5.25% NaOCl in a single mixture. Groups 1 and 2 were divided into 2 subgroups (n = = 10) according to the time of restoration: immediate (subgroup A) and after 7 days (subgroup B). Four other groups (n = 10) were created according to the dentin surface pretreatment and received an immediate restoration: group 3: 5.25% NaOCl - 17% EDTA and AH Plus Cleaner; group 4: 5.25% NaOCl - 17% EDTA and 100% ethanol; group 5: 5.25% NaOCl + 18% HEDP and AH Plus Cleaner; group 6: 5.25% NaOCl + 18% HEDP and 100% ethanol. µTBS testing was carried out for each subgroup and interfaces were analyzed through SEM. The µTBS was analyzed with Welch statistics and the post-hoc Games-Howell test for multiple comparisons (p < 0.05). RESULTS: Statistically significant differences were observed between test groups and control groups (p < 0.001), except for group 3 (p = 0.349). No significant differences were recorded between groups 1A (27.5 ± 8.7 MPa), 2A (32.6 ± 14.5 MPa) and 3 (27.3 ± 14.3 MPa). Group 6 (48.6 ± 11.6 MPa) exhibited the highest µTBS among all tested groups. For groups 1 and 2, significantly higher values were recorded for subgroups 1B (39.3 ± 7.6 MPa) and 2B (43.8 ± 8.3 MPa) compared to subgroups 1A (27.5 ± 8.7 MPa) and 2A (32.6 ± 14.5 MPa). CONCLUSION: When using NaOCl as root canal irrigant, it is advisable to delay the placement of a post-endodontic-treatment restoration.


Assuntos
Colagem Dentária , Cimentos Dentários , Cavidade Pulpar , Análise do Estresse Dentário , Dentina , Ácido Edético , Teste de Materiais , Irrigantes do Canal Radicular , Preparo de Canal Radicular , Hipoclorito de Sódio
13.
J Appl Oral Sci ; 29: e20200266, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33825761

RESUMO

OBJECTIVES: We analyzed the effects of the Er:YAG laser used with different parameters on dentinal tubule (DT) occlusion, intrapulpal temperature and pulp tissue morphology in order to determine the optimal parameters for treating dentin hypersensitivity. METHODOLOGY: Dentin specimens prepared from 36 extracted human third molars were randomized into six groups according to the treatment method (n=6 each): control (A); Gluma desensitizer (B); and Er:YAG laser treatment at 0.5 W , 167 J/cm2 (50 mJ, 10 Hz) (C), 1 W , 334 J/cm2 (50 mJ, 20 Hz) (D), 2 W , 668 J/cm2 (100 mJ, 20 Hz) (E), and 4 W and 1336 J/cm2 (200 mJ, 20 Hz) (F). Treatment-induced morphological changes of the dentin surfaces were assessed using scanning electron microscopy (SEM) to find parameters showing optimal dentin tubule occluding efficacy. To further verify the safety of these parameters (0.5 W, 167 J/cm2), intrapulpal temperature changes were recorded during laser irradiation, and morphological alterations of the dental pulp tissue were observed with an upright microscope. RESULTS: Er:YAG laser irradiation at 0.5 W (167 J/cm2) were found to be superior in DT occlusion, with an exposure rate significantly lower than those in the other groups (P<0.05). Intrapulpal temperature changes induced by Er:YAG laser irradiation at 0.5 W (167 J/cm2) with (G) and without (H) water and air cooling were demonstrated to be below the threshold. Also, no significant morphological alterations of the pulp and odontoblasts were observed after irradiation. CONCLUSION: Therefore, 0.5 W (167 J/cm2) is a suitable parameter for Er:YAG laser to occlude DTs, and it is safe to the pulp tissue.


Assuntos
Lasers de Estado Sólido , Oclusão Dentária , Dentina , Humanos , Lasers de Estado Sólido/uso terapêutico , Microscopia Eletrônica de Varredura
14.
J Appl Oral Sci ; 29: e20200736, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33825753

RESUMO

OBJECTIVE: To evaluate the efficacy of Nd:YAG laser associated with calcium-phosphate desensitizing pastes on dentin permeability and tubule occlusion after erosive/abrasive challenges. METHODOLOGY: Dentin specimens were exposed to 17% ethylene diamine tetra-acetic acid (EDTA) solution for 5 min and randomly allocated into five groups: G1, control (no treatment); G2, Nd:YAG laser (1 W, 10 Hz, 100 mJ, 85 J/cm2); G3, Laser + TeethmateTM Desensitizer; G4, Laser + Desensibilize Nano P; and G5, Laser+Nupro®. Specimens underwent a 5-day erosion-abrasion cycling. Hydraulic conductance was measured post-EDTA, post-treatment, and post-cycling. Post-treatment and post-cycling permeability (%Lp) was calculated based on post-EDTA measurements, considered 100%. Open dentin tubules (ODT) were calculated at the abovementioned experimental moments using scanning electron microscopy and ImageJ software (n=10). Data were analyzed using two-way repeated measures ANOVA and Tukey's test (α=0.05). RESULTS: G1 presented the highest %Lp post-treatment of all groups (p<0.05), without significantly differences among them. At post-cycling, %Lp significantly decreased in G1, showed no significant differences from post-treatment in G3 and G4, and increased in G2 and G5, without significant differences from G1 (p>0.05). We found no significant differences in ODT among groups (p>0.05) post-EDTA. At post-treatment, treated groups did not differ from each other, but presented lower ODT than G1 (p<0.001). As for post-cycling, we verified no differences among groups (p>0.05), although ODT was significantly lower for all groups when compared to post-EDTA values (p<0.001). CONCLUSION: All treatments effectively reduced dentin permeability and promoted tubule occlusion after application. COMBINING ND: YAG laser with calcium-phosphate pastes did not improve the laser effect. After erosive-abrasive challenges, treatments presented no differences when compared to the control.


Assuntos
Dessensibilizantes Dentinários , Lasers de Estado Sólido , Cálcio/farmacologia , Dentina , Permeabilidade da Dentina , Lasers de Estado Sólido/uso terapêutico , Microscopia Eletrônica de Varredura
15.
J Appl Oral Sci ; 29: e20200859, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33886942

RESUMO

INTRODUCTION: Due to its ability to arrest untreated dental caries, silver diamine fluoride (SDF) has been advocated for indirect pulp capping procedures. However, the high concentrations of silver and fluoride in SDF raise concerns about its biocompatibility to pulpal tissues. OBJECTIVES: This study aimed to investigate the effect of SDF on the viability, alkaline phosphatase (ALP) activity, and morphology of pulpal-like cells (RPC-C2A) and to evaluate the influence of reduced glutathione (GSH) on SDF-induced cytotoxicity and deposit formation on dentin. METHODOLOGY: The cytotoxicity of diluted 38% SDF solutions (10-4 and 10-5), with or without the addition of 5 mM or 50 mM GSH, was evaluated at 6 and 24 hours. Cell viability was detected using WST-8 and the effect on ALP activity was performed using an ALP assay kit. Cell morphology was observed using a phase-contrast microscope. Scanning electron microscopy analysis was conducted to evaluate the effect of GSH incorporation or conditioning on SDF-induced deposit formation on dentin discs. Cytotoxicity data were analyzed by two-way analysis of variance (ANOVA) and Tukey post hoc tests (p<0.05). RESULTS: There were significant differences between the groups. The results demonstrated that all tested SDF dilutions caused a remarkable cytotoxic effect, while the addition of GSH prevented SDF-induced damage at 6-hour exposure time in the higher dilution of SDF. Dentin treated with plain SDF or GSH-incorporated SDF solution showed deposit formation with occluded dentinal tubules, unlike the other groups. CONCLUSION: SDF severely disturbed the viability, mineralization-ability, and morphology of pulpal-like cells, while controlled concentrations of GSH had a short-term protective effect against SDF-induced damage. GSH showed an inhibitory effect on SDF-induced dentinal deposit formation. Further research is warranted to evaluate the effect of GSH on caries-arresting, anti-hypersensitivity, and antibacterial functions of SDF.


Assuntos
Cárie Dentária , Animais , Cariostáticos/toxicidade , Dentina , Fluoretos Tópicos/toxicidade , Glutationa , Compostos de Amônio Quaternário , Ratos , Compostos de Prata
16.
Sud Med Ekspert ; 64(2): 46-50, 2021.
Artigo em Russo | MEDLINE | ID: mdl-33739070

RESUMO

The study of the amino acid composition of dentin is a new approach to determining the biological age of a person in Russia. Abroad, this method is more studied, but the authors in their research use various equipment and reagents, which makes it difficult to find the optimal technical standard for implementation in domestic practice. We studied the literature over the past 5 years on age estimation by the amino acid composition of dentin. The equipment used in the work and the results obtained were compared. A comparative evaluation of the data made it possible to make an assumption about gas chromatography using mass selective or flame ionization detectors as a method of choice for studying the amino acid composition of tooth dense tissues.


Assuntos
Determinação da Idade pelos Dentes , Envelhecimento , Ácido Aspártico , Dentina , Humanos , Federação Russa
17.
Niger J Clin Pract ; 24(3): 418-424, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33723118

RESUMO

Objectives: The aim of this study was to compare the formation of dentinal crack after root canal preparation performed with different heat treated single-file systems. Materials and Methods: Forty mandibular premolar teeth were randomly divided into four groups according to the file system to be used during the preparation (n = 10): Group 1: Reciproc Blue; group 2: One Curve; group 3: HyFlex EDM; group 4: (control group) hand files. During the cleaning and shaping, irrigation was performed with a total of 10 ml of 5.25% sodium hypochlorite and 2 mL of distilled water. Then sections were taken from the roots (3, 6 and 9 mm). Sections were examined on a stereomicroscope to determine the presence of cracks. Chi-square test was used for data analysis. Results: There was a significant difference between the groups in dentinal crack frequency (P <.05). HyFlex EDM (13.3%) caused less dentinal crack than One Curve (26.7%) and Reciproc Blue (30%). No cracks were observed in the control group. When 3, 6, and 9 mm were evaluated within themselves, dentinal crack formation did not differ according to the groups (P > 0.05). A statistically higher mean value was obtained in the control group compared to the other groups in terms of working time (P < 0.001). Conclusions: All the files used during root canal preparation formed dentin crack. Hy-Flex EDM caused less dentinal cracks than other file systems. The flexibility of nickel-titanium instruments because of heat treatment seems to have a significant influence on dentinal crack formation.


Assuntos
Dentina , Temperatura Alta , Mãos , Humanos , Preparo de Canal Radicular , Hipoclorito de Sódio
18.
Eur J Oral Sci ; 129(2): e12771, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33644893

RESUMO

We evaluated the effect of phytic acid on matrix metalloproteinase (MMP)- or cysteine cathepsin (CC)-mediated dentin degradation. Demineralized dentin beams were divided into five groups (n = 12) and treated with 1%, 2%, or 3% phytic acid or with 37% phosphoric acid. Untreated demineralized beams served as controls. After incubation for 1 or 3 wk, dry mass loss was determined and aliquots of incubation media were analysed for cross-linked telopeptide of type I collagen (ICTP) fragments for MMP-mediated and c-terminal telopeptide of type I collagen (CTX) for cathepsin-k-mediated degradation. The direct effect of phytic acid was evaluated using MMP activity assay. Data were analysed using repeated-measures anova. ICTP releases with 1% and 2% phytic acid treatment were statistically significantly lower than those following phosphoric acid treatment at 3 wk. The CTX release for phytic acid-treated beams at 3 wk was not significantly different from that of untreated control beams, but it was significantly lower than that of phosphoric acid-treated beams. Their MMP activities at 3 wk were not significantly different from those of the controls but they were significantly lower than those seen for phosphoric acid-treated beams. Compared to phosphoric acid, phytic acid treatment resulted in a reduced dentinal host-derived endogenous enzymatic activity and collagen degradation.


Assuntos
Dentina , Ácido Fítico , Colágeno Tipo I , Metaloproteinases da Matriz , Ácido Fítico/farmacologia
19.
BMC Oral Health ; 21(1): 97, 2021 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-33663454

RESUMO

BACKGROUND: The purpose of this prospective clinical diagnostic study with validation was to compare the diagnostic accuracy of near-infrared transillumination (NIRT), laser fluorescence measurement (LF), alternating current impedance spectroscopy (ACIS) and their combinations as adjunct methods to visual examination (VE) for occlusal caries detection using a hybrid reference standard. METHODS: Ninety-six first and second non-cavitated permanent molars from 76 individuals (mean age 24.2) were investigated using (VE) (ICDAS) and bitewing radiography (BWR), as well as NIRT, LF and ACIS. The findings of BWR and NIRT were evaluated by two examiners while the other examinations were conducted by one calibrated dentist. The hybrid reference standard consisted of non-operative validation based on the results of VE and BWR and operative validation. Statistical analysis included cross-tabulations, calculation of sensitivity, specificity and area under the receiver operating characteristic curve at three diagnostic thresholds: caries in general, enamel caries and dentin caries. RESULTS: NIRT, LF and ACIS exhibited high sensitivity for caries in general [1.00 (1.00-1.00), 0.77 (0.65-0.88), 0.75 (0.63-0.87)) and for dentin caries (0.97 (0.91-1.03), 0.76 (0.76-0.90), 0.64 (0.47-0.80)]. Sensitivity values for enamel caries were weak (0.21, 0.11, 0.37). Specificity values did not fall below 0.65 (NIRT) for all categories and methods, except for NIRT at the caries detection threshold (0.27). A combination of LF and ACIS with VE improved the diagnostic performance at the overall and the enamel caries threshold. The other methods showed fair to excellent discrimination at the overall caries threshold (NIRT 0.64, LF 0.89 and ACIS 0.86) and acceptable discrimination at the dentin caries threshold (NIRT 0.82, LF 0.81 and ACIS 0.79). AUROC for enamel caries exhibited the weakest discrimination. Accuracy was 65.6% for VE, 69.8% for BWR, 50.0% for NIRT, 53.1% for LF and 74.0% for ACIS. Reliability assessment for BWR and NIRT showed at least substantial agreements for all analyses. CONCLUSIONS: The methods, NIRT, LF and ACIS, revealed different potential but no impeccable performance for occlusal caries detection. All are suitable instruments to detect hidden carious lesion in dentin. As auxiliaries to VE, LF and ACIS showed an increase in diagnostic performance.


Assuntos
Suscetibilidade à Cárie Dentária , Cárie Dentária , Adulto , Cárie Dentária/diagnóstico por imagem , Dentina , Fluorescência , Humanos , Estudos Prospectivos , Radiografia Interproximal , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
20.
Eur J Oral Sci ; 129(2): e12769, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33667031

RESUMO

This study evaluated the effects of 9% etidronic acid (HEBP) and 17% ethylenediaminetetraacetic acid (EDTA) used either with conventional syringe irrigation (CSI) or passive ultrasonic irrigation (PUI) on the fracture resistance of roots with different dentine thickness. The root canals of 120 extracted teeth were widened, leaving dentinal walls with different thicknesses of either 0.75 mm, 1.50 mm, or 2.25 mm with 40 teeth in each group. Within each of these groups, four subgroups (n = 10) were formed according to the final irrigation regimens applied: 2.5% NaOCl-17% EDTA with CSI; 2.5% NaOCl-17% EDTA with PUI; 2.5% NaOCl + 9% HEBP with CSI; 2.5% NaOCl + 9% HEBP with PUI. The irrigated root canals were obturated with AH Plus sealer and gutta-percha cones. A compressive vertical loading was applied to the samples and the force at fracture was recorded. Data were statistically analysed using a multiple linear regression analysis. The most influencing factor for the fracture strength of roots was the remaining dentine thickness, followed by the irrigation method, and then the irrigation solution. The samples irrigated using PUI were statistically significantly more resistant to fracture than those using CSI (mean difference = 116.3 N; 95% CI = [53.9, 178.6] N). The application of HEBP was associated with higher resistance to fracture than the application of EDTA (mean difference = 71.0 N; 95% CI = [8.6, 133.3] N).


Assuntos
Irrigantes do Canal Radicular , Hipoclorito de Sódio , Cavidade Pulpar , Dentina , Ácido Edético , Preparo de Canal Radicular , Irrigação Terapêutica
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