RESUMO
The aim was to compare the effect of different endodontic surgical treatments on the stress distributions in dentin of a simulated first mandibular molar tooth using the finite element analysis method. Three surgical endodontic procedures (apical resection, root amputation, and hemisection) were simulated in a first mandibular molar. Biodentine or mineral-trioxide-aggregate was used to repair the surgery site in apical resection and root amputation models; the remaining root canal spaces were filled with gutta-percha. Access cavities were restored using resin composite. In hemisection model, root canal was filled with gutta-percha, and coronal restoration was finished with a monolithic zirconia crown. A sound tooth model was created as a control model. An oblique force of 300 N angled at 45° to the occlusal plane was simulated. Maximum von Mises stresses were evaluated in dentin near the surgery regions and the entire tooth. Apical resection/Biodentine and apical resection/mineral-trioxide-aggregate models generated maximum von Mises stresses of 39.001 MPa and 39.106 MPa, respectively. The recorded maximum von Mises stresses in root amputation models were 66.491 MPa for root amputation/Biodentine and 73.063 MPa for root amputation/mineral-trioxide-aggregate models. The highest maximum von Mises stress value among all models was observed in the hemisection model, measuring 138.87 MPa. Hemisection induced the highest von Mises stresses in dentin, followed by root amputation and apical resection. In apical resection, Biodentine and mineral-trioxide-aggregate did not show a significant difference in stress distribution. Biodentine in root amputation may lead to lower stresses compared to mineral-trioxide-aggregate.
Assuntos
Compostos de Cálcio , Análise do Estresse Dentário , Dentina , Análise de Elementos Finitos , Dente Molar , Óxidos , Silicatos , Humanos , Dente Molar/cirurgia , Compostos de Alumínio , Materiais Restauradores do Canal Radicular , Mandíbula/cirurgia , Guta-Percha , Zircônio , Raiz Dentária/cirurgia , Combinação de MedicamentosRESUMO
The ethylenediaminetetradiacetic acid (EDTA) is one of the most commonly used irrigation solutions. Although EDTA has a very low antimicrobial property, it is used to remove inorganic part of smear layer in areas of root canal system. Herein, we developed EDTA-incorporated nanoflowers (EDTA NFs), for the first time, as novel and effective irrigation solution with quite high antimicrobial property to provide complete disinfection in root canal system. We both systematically elucidated the formation of the EDTA NFs with various techniques, and their catalytic and antimicrobial activities in the presence of hydrogen peroxide (H2O2) were documented through intrinsic EDTA property and peroxidase-like activities.
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Anti-Infecciosos , Camada de Esfregaço , Humanos , Desinfecção/métodos , Ácido Edético/farmacologia , Peróxido de Hidrogênio/farmacologia , Biofilmes , Irrigantes do Canal Radicular/farmacologia , Cavidade Pulpar , Hipoclorito de Sódio , Preparo de Canal Radicular/métodosRESUMO
OBJECTIVES: To compare the root canal microbiome profiles of primary and persistent/secondary infections using high-throughput sequencing with the help of a reliable bioinformatics algorithm. MATERIALS AND METHODS: Root canal samples of 10 teeth in the primary endodontic infection (PEI) group and 10 teeth in the persistent/secondary endodontic infection (SEI) group were included resulting in a total of 20 samples. After DNA extraction from the samples, sequencing was performed on the Illumina MiSeq platform. Pair-end Illumina reads were imported to QIIME 2; amplicon sequence variants (ASVs) generated by DADA2 were mapped to GreenGenes database. Weighted UniFrac distances were calculated and principal coordinates analysis (PCoA) was used to compare beta diversity patterns. The multiple response permutation procedure (MRPP), the analysis of similarities (ANOSIM), and permutational multivariate analysis of variance (adonis) were conducted for testing group differences. Linear discriminant analysis effect size (LEfSe) analysis was utilized to identify differentially abundant taxa between the groups. The linear discriminant analysis (LDA) score threshold was set to 4.0. RESULTS: Within the Gram-negative facultative anaerobic Gammaproteobacteria class outgroup, two orders (Pasteurellales, Vibrionales) and two families (Pasteurellaceae, Vibrionaceae) were significantly more abundant in the PEI group, whereas Gram-positive bacteria, Actinomycetales order, and Gram-positive anaerobic taxa, one genus (Olsenella) and one species (Olsenella uli), were identified as significantly more abundant in the SEI group. CONCLUSIONS: A few taxa were differentially abundant within either the PEI or SEI group. CLINICAL RELEVANCE: Reliable bioinformatic tools are needed to define microbial profiles of endodontic infections. Based on a limited number of samples, no distinct variation was determined between the bacterial diversity of initial and recurrent endodontic infections.
Assuntos
Coinfecção , Microbiota , Humanos , Cavidade Pulpar/microbiologia , Tratamento do Canal Radicular , Microbiota/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , RNA Ribossômico 16S/genéticaRESUMO
OBJECTIVES: The purpose of the present study was to determine the dislodgement resistance of AH Plus, MTA Fillapex, and Total Fill BC sealer to root canal dentin walls following placement of calcium hydroxide (CH) or double antibiotic paste (DAP) medicaments. MATERIALS AND METHODS: Root canals of 90 single-rooted human mandibular premolar teeth were instrumented with Reciproc rotary instruments to a size R50. The teeth were randomly divided into two experimental groups: those receiving an intracanal medicament with either CH or DAP and a control group (n = 30). After 3 weeks, the medicaments were removed by irrigation with 5 mL of 2.5 % NaOCl, 5 mL 17 % EDTA, and 5 mL distilled water under sonic agitation. Each group was then subdivided into three subgroups (n = 10), and the canals were filled with either AH Plus, MTA Fillapex, or Total Fill BC sealer. After 1 week, a push-out test was applied to the specimens and the results were analyzed using one-way analysis of variance (ANOVA) and post hoc Tamhane's tests. RESULTS: Regardless of the type of intracanal medicament used, Total Fill BC Sealer and MTA Fillapex showed the highest and lowest bond strength, respectively (P < 0.05). The use or absence of medicaments did not significantly affect the dislodgment resistance of root canal fillings (P > 0.05). Prior CH placement improved dislodgement resistance of all sealers without statistical difference (P > 0.05). Adhesive failure between core and sealer was the most frequent failure mode. CONCLUSIONS: Prior application of CH or DAP did not significantly affect the adhesion of the AH Plus, MTA Fillapex, and Total Fill BC Sealers. CLINICAL RELEVANCE: There is a little information about the influence of antibiotic medicaments on the bond strength of root canal sealer. These findings suggest that the use of DAP does not affect the adhesion strength of AH Plus, MTA Fillapex, and Total Fill BC Sealers.
Assuntos
Antibacterianos/química , Ciprofloxacina/química , Resinas Epóxi/química , Metronidazol/química , Materiais Restauradores do Canal Radicular/química , Dente Pré-Molar , Compostos de Cálcio/química , Hidróxido de Cálcio/química , Colagem Dentária , Análise do Estresse Dentário , Combinação de Medicamentos , Humanos , Técnicas In Vitro , Teste de Materiais , Irrigantes do Canal Radicular/química , Silicatos/química , Estresse MecânicoRESUMO
OBJECTIVE: The aim of this study was to evaluate the effect of residual calcium hydroxide [Ca(OH)2] on the accuracy of an electronic apex locator (EAL). MATERIALS AND METHODS: Working lengths (WLs) of 56 extracted maxillary incisors were determined initially by two different methods. The first method used the 'APEX' reading of the EAL as a reference point, 0.5 mm was subtracted and recorded as WL0. The second method used the '0.5' reading and the score was recorded as WL0.5 without subtraction. The roots were prepared to WL0 and divided randomly into three experimental groups (n = 16) (1 mm in group A, 2 mm in group B and 4 mm in group C) and a control (n = 8). Specimens in all experimental groups were filled with Ca(OH)2 paste. Following its removal, WLs were re-determined with the same methods. RESULTS: In group C, pre/post WLs were significantly different (p < 0.05). No significant difference was observed between the other experimental groups and the control group. CONCLUSION: Accuracy of EAL decreased proportionally with the amount of paste remaining at the ±0.5-mm tolerance level. Ca(OH)2 paste remnants may cause incorrect EAL readings.
Assuntos
Hidróxido de Cálcio/química , Cavidade Pulpar/anatomia & histologia , Equipamentos e Provisões Elétricas/estatística & dados numéricos , Odontometria/instrumentação , Irrigantes do Canal Radicular/química , Preparo de Canal Radicular/instrumentação , Ápice Dentário/anatomia & histologia , Humanos , Incisivo/anatomia & histologia , Teste de Materiais , Odontometria/estatística & dados numéricos , Distribuição Aleatória , Preparo de Canal Radicular/métodosRESUMO
PURPOSE: The aim of the present prospective, randomized, controlled, clinical study was to compare the outcomes of periradicular surgery of the maxillary first molar tooth using the vestibular approach between 2 preoperative radiologic evaluation methods: cone beam computed tomography (CBCT) and conventional radiography. PATIENTS AND METHODS: Periradicular surgery was applied to the maxillary first molar tooth in 40 patients. The patients were divided into 2 groups. The patients in group 1 underwent examination and preoperative planning with CBCT, and the patients in group 2 underwent examination and preoperative planning with conventional radiography. The outcomes of the treatment were evaluated radiographically and clinically, and the data were analyzed statistically. RESULTS: The mean operative time was significantly shorter in group 1 than in group 2. According to the radiographic and clinical healing criteria used in the present study, the healing of patients in group 1 was rated as a success in 35%, an improvement in 40%, and a failure in 25%. In the group 2 patients, healing was rated as a success in 42.1%, an improvement in 31.6%, and a failure in 26.3%. Sinus membrane elevation was performed in 92.3% of all patients. Sinus membrane perforation occurred in 20% of the patients in group 1 and 36.8% of the patients in group 2. CONCLUSIONS: Periradicular surgery of maxillary first molars using a vestibular approach is a viable treatment method with a low complication rate. Preoperative CBCT examination demonstrated positive contributions to the treatment outcomes.
Assuntos
Maxila/cirurgia , Dente Molar/cirurgia , Raiz Dentária/cirurgia , Abscesso/etiologia , Apicectomia/métodos , Tomografia Computadorizada de Feixe Cônico/métodos , Fístula Dentária/etiologia , Edema/etiologia , Feminino , Seguimentos , Humanos , Complicações Intraoperatórias , Masculino , Maxila/diagnóstico por imagem , Seio Maxilar/diagnóstico por imagem , Seio Maxilar/lesões , Dente Molar/diagnóstico por imagem , Mucosa Nasal/lesões , Duração da Cirurgia , Osteotomia/métodos , Medição da Dor , Planejamento de Assistência ao Paciente , Doenças Periapicais/diagnóstico por imagem , Doenças Periapicais/cirurgia , Complicações Pós-Operatórias , Estudos Prospectivos , Obturação Retrógrada/métodos , Preparo de Canal Radicular/métodos , Retalhos Cirúrgicos/cirurgia , Ápice Dentário/diagnóstico por imagem , Ápice Dentário/cirurgia , Raiz Dentária/diagnóstico por imagem , Resultado do Tratamento , Cicatrização/fisiologiaRESUMO
OBJECTIVE: The purpose of the present study is to evaluate the effects of systemically administered zoledronic acid (ZA) on the physiological bone remodeling and the microarchitectural parameters of the condylar part of TMJ in a rabbit model. STUDY DESIGN: Thirty skeletally mature male New Zealand white rabbits were randomly divided into two groups. The experimental group was administered an intravenous, single dose of 0.1 mg/kg ZA diluted with 15 mL of saline in a 15-minute perfusion with an infusion pump. The control group was administered only saline infusion for 15 minutes. All rabbits were sacrificed on the 21st postoperative day. Radiodensitometric and histomorphometric examinations were performed on the harvested mandibular condyles. The data were analyzed statistically. RESULTS: Radiodensitometric findings showed that ZA treatment resulted in a significant increase in the mineralization of mandibular condyle. This result was supported by the histomorphometric findings. CONCLUSION: The present study has revealed that a temporary delay in the physiological bone remodeling using single dose of ZA increases bone mineral content and makes the microarchitecture of the mandibular condyle more compact. These effects may be regarded as base data and considered in numerous clinical situations including TMJ.
Assuntos
Remodelação Óssea/efeitos dos fármacos , Difosfonatos/farmacologia , Imidazóis/farmacologia , Articulação Temporomandibular/efeitos dos fármacos , Animais , Masculino , Coelhos , Radiografia , Articulação Temporomandibular/anatomia & histologia , Articulação Temporomandibular/diagnóstico por imagem , Ácido ZoledrônicoRESUMO
PURPOSE: The objective of this study was to evaluate the diagnostic concordance characteristics of oral cavity lesions by comparing the clinical diagnosis of the lesions with the histopathologic diagnosis. MATERIAL AND METHOD: A retrospective analysis was conducted on the patients, who were admitted with oral cavity pathology and underwent biopsy procedure between 2007 and 2011. The oral cavity lesions were classified into 6 different groups as odontogenic cysts, nonodontogenic cysts, odontogenic tumors, nonodontogenic tumors, malignant tumors, and precancerous lesions in accordance with the 2005 WHO classification. The diagnoses were also recategorized into 3 groups expressing prognostic implications as benign, precancerous, and malignant. The initial clinical diagnoses were compared with the histopathologic diagnoses. Data were analyzed statistically. RESULTS: A total of 2718 cases were included. Histopathologic diagnosis did not match the clinical diagnosis in 6.7% of the cases. Nonodontogenic tumors and malignant tumors had the highest misdiagnosis rates (11.5% and 9%, resp.), followed by odontogenic tumors (7.7%), precancerous lesions (6.9%), and odontogenic cysts (4.4%). Clinicians were excelled in diagnosis of benign and precancerous lesions in clinical setting. CONCLUSION: The detailed discordance characteristics for each specific lesion should be considered during oral pathology practice to provide early detection without delay.
Assuntos
Doenças da Boca/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Criança , Pré-Escolar , Feminino , Humanos , Doenças Maxilomandibulares/diagnóstico , Doenças Maxilomandibulares/patologia , Neoplasias Maxilomandibulares/diagnóstico , Neoplasias Maxilomandibulares/patologia , Masculino , Pessoa de Meia-Idade , Doenças da Boca/patologia , Neoplasias Bucais/diagnóstico , Neoplasias Bucais/patologia , Cistos Odontogênicos/diagnóstico , Cistos Odontogênicos/patologia , Tumores Odontogênicos/diagnóstico , Tumores Odontogênicos/patologia , Exame Físico , Lesões Pré-Cancerosas/diagnóstico , Lesões Pré-Cancerosas/patologia , Prevalência , Reprodutibilidade dos Testes , Estudos Retrospectivos , Distribuição por Sexo , Adulto JovemRESUMO
The effects of three dissolving agents on the accuracy of an electronic apex locator- (EAL-) integrated endodontic handpiece during retreatment procedures were evaluated. The true lengths (TLs) of 56 extracted incisor teeth were determined visually. Twenty teeth were filled with gutta-percha and a resin-based sealer (group A), 20 with gutta-percha and a zinc oxide/eugenol-based sealer (group B), and 16 roots were used as the control group (group C). All roots were prepared to TL. Guttasolv, Resosolv, and Endosolv E were used as the dissolving solutions. Two evaluations of the handpiece were performed: the apical accuracy during the auto reverse function (ARL) and the apex locator function (EL) alone. The ARL function of the handpiece gave acceptable results. There were significant differences between the EL mode measurements and the TL (P < 0.05). In these comparisons, Tri Auto ZX EL mode measurements were significantly shorter than those of the TL.
Assuntos
Materiais Restauradores do Canal Radicular , HumanosRESUMO
This study aimed to evaluate the frontal bone of Swiss Domestic pigs as an animal model for the histologic-histomorphometric examination of bony tissue around dental implants. We inserted SLA surface implants 4.1 mm in diameter and 10 mm in length into the frontal bones of 9 Swiss-Domestic pigs. Histologic and histomorphometric studies were conducted on the undecalcified sections. Histologic examinations showed that the specimens contain a sufficient amount of bone to provide homogenous bone coverage for standard diameter dental implant placement. The mean bone to implant contact was 61.9% ± 8.7%. Other histomorphometric parameters revealed the regular trabecular architecture at this site. Pigs' frontal bone appears to be a suitable animal model in short-term dental implant studies because it provides a sufficient amount of bone and favorable bone microarchitecture.
Assuntos
Implantes Dentários , Osso Frontal/anatomia & histologia , Modelos Animais , Osseointegração , Suínos , Animais , Densidade ÓsseaRESUMO
It is essential to create a glide path before root canal preparation with nickel-titanium rotary files to avoid file breakage and preserve the original canal structure. The aim of this study was to compare the amount of apically extruded debris after using different glide path files. A total of 96 first mandibular molars with curved mesial roots were randomly divided into six groups (n = 16) which are K-files, Proglider, R-Pilot, TruNatomy Glider, WaveOne Gold Glider and group without a glide path. Apically extruded debris was measured after glide path and canal preparation. The highest amount of debris was found in the control group without a glide path and using a glide path file caused less debris and significant differences were observed between R-Pilot, TruNatomy Glider, ProGlider, WaveOne Gold Glider and K-file groups. It may be recommended to create a glide path before root canal shaping to reduce the amount of extrusion debris from the apical. Especially in curved and narrow root canals, it is recommended to use an R-Pilot file before root canal shaping in order to reduce the amount of apically extruded debris.
Assuntos
Cavidade Pulpar , Raiz Dentária , Cavidade Pulpar/cirurgia , Preparo de Canal Radicular , Dente Molar/cirurgia , OuroRESUMO
Purpose: The aim of this study was, firstly, to determine the concordance of ultrasonographic and histopathological diagnoses in patients in whom apical resection was already indicated. Secondly, this study aimed to determine whether lesions were periapical granulomas or cysts, and to compare them after root canal treatment using ultrasonography and periapical radiographs. Materials and Methods: In the first stage of the study, ultrasonographic and histopathologic diagnoses of 10 lesions were compared. Secondly, the periapical radiographs and ultrasonographic images of 44 lesions were measured. The presence of internal vascularity was determined by ultrasonographic color and power Doppler modes. Follow-up examinations of healing after root canal treatment were performed using ultrasonography and periapical radiographs, and these modalities were compared. Results: In the periapical granuloma and cyst groups, the measurement values decreased for all variables. There was no significant difference in the dimensional changes of lesions between the 2 groups, and ultrasonography and periapical radiographs were compatible. The pre-diagnoses were compared with histopathological diagnoses and were found to be compatible. Conclusion: The ultrasonographic color and power Doppler techniques could be an effective method for diagnosing periapical lesions as cysts or granulomas. After root canal treatment of granulomas and cysts, the dimensional shrinkage and healing patterns appear to be similar. Ultrasonography and periapical radiographs were consistent in terms of dimensional comparisons, and ultrasonography may be an alternative method for follow-up of the healing of periapical lesions.
RESUMO
PURPOSE: The purpose of the present study was to evaluate the effects of systemically administered zoledronic acid (ZA) on mandibular fracture healing in a rabbit model using radiodensitometric, biomechanical, histologic, and histomorphometric methods. MATERIALS AND METHODS: A total of 36 skeletally mature male New Zealand white rabbits were used. The rabbits were randomly divided into 2 groups. A mandibular corpus fracture was created experimentally in all 36 rabbits. The experimental group was administered an intravenous, single dose of 0.1 mg/kg ZA, and the control group was administered only saline infusion during the procedure. All rabbits were sacrificed on the 21st postoperative day. Digital radiodensitometric analysis, a 3-point bending test, and histologic and histomorphometric examinations were performed on the harvested hemimandibles. The data were analyzed statistically. RESULTS: Biomechanical testing data showed that ZA treatment resulted in a significant increase in the healed bone strength. This result was supported by the radiologic, histologic, and histomorphometric findings. CONCLUSIONS: The results of the present study have revealed that systemic administration of ZA accelerates and improves the bone healing of mandibular fractures.
Assuntos
Conservadores da Densidade Óssea/farmacologia , Difosfonatos/farmacologia , Consolidação da Fratura/efeitos dos fármacos , Imidazóis/farmacologia , Fraturas Mandibulares/fisiopatologia , Animais , Fenômenos Biomecânicos , Masculino , Fraturas Mandibulares/patologia , Coelhos , Ácido ZoledrônicoRESUMO
AIM: This in vitro study evaluated the effect of different cavity disinfection agents on bond strength of a silorane-based resin composite. MATERIALS AND METHODS: Thirty-six caries-free human third mandibular molars sectioned in mesio-distal direction were mounted in acrylic resin with their flat dentin surfaces exposed. After the dentin surfaces were wet ground with # 600 silicon carbide paper, the teeth were randomly divided into 6 groups of 12 each according to the cavity disinfection agents; chlorhexidine (CHX); sodium hypochlorite (NaOCl), propolis, ozone, Er,Cr:YSGG laser and no treatment (control). After treatment of dentin surfaces with one of these cavity disinfection agents, Filtek Silorane adhesive system was applied. The silorane-based resin composite, Filtek Silorane was condensed into a mold and polymerized. After storage at 37°C for 24 hours, the specimens were tested in shear mode at a crosshead speed of 1.0 mm/minute. The results were analyzed by one-way ANOVA. RESULTS: No statistically significant difference was observed between the groups (p>0.05). CONCLUSION: The use of the tested cavity disinfection agents, chlorhexidine, sodium hypochlorite, propolis, ozone and Er,Cr:YSGG laser did not significantly affect the dentin bond strength of a silorane-based resin composite, filtek supreme. CLINICAL SIGNIFICANCE: Cavity disinfectant applications did not affect the dentin bond strength of a silorane-based resin composite.
Assuntos
Anti-Infecciosos Locais , Resinas Compostas , Colagem Dentária , Preparo da Cavidade Dentária , Restauração Dentária Permanente , Adesivos Dentinários , Siloxanas , Análise de Variância , Clorexidina , Desinfetantes de Equipamento Odontológico , Análise do Estresse Dentário , Humanos , Lasers de Estado Sólido , Teste de Materiais , Ozônio , Própole , Cimentos de Resina , Resistência ao Cisalhamento , Resinas de Silorano , Hipoclorito de SódioRESUMO
INTRODUCTION: In this study, finite element analysis was used to evaluate the stress distributions in simulated mandibular molar teeth with various iatrogenic root perforation types after reparation with Biodentine (Septodont, Saint-Maur-des-Fossés, France) or mineral trioxide aggregate (MTA). METHODS: An extracted human mandibular molar tooth was scanned using a micro-computed tomographic device, and a 3-dimensional solid model was created. Then, 3 different iatrogenic perforation types (furcation perforation [FP], strip perforation [SP], and post drill perforation [PDP]) and 2 different repair materials (MTA and Biodentine [BD]) were simulated on the model. In addition, a sound tooth (ST) model (control) and a model left unrepaired for each type of perforation were created; then, access cavities were restored using resin composite, except for the sound tooth model. Consequently, a total of 10 experimental models were designed. An oblique force of 300 N angled at 45° to the occlusal plane was simulated. Evaluations of von Mises stress were performed in the perforated regions. RESULTS: Maximum von Mises stress values were 7.76 MPa for ST/corresponding to the FP region, 8.48 MPa for ST/corresponding to the SP region, 14.20 MPa for ST/corresponding to the PDP region, 10.89 MPa for FP /MTA, 7.65 MPa for FP/BD, 14.67 MPa for FP/unrepaired, 15.92 MPa for SP/MTA, 15.82 MPa for SP/BD, 21.95 MPa for SP/unrepaired, 10.20 MPa for PDP/MTA, 9.17 MPa for PDP/BD, and 17.86 MPa for PDP/unrepaired. CONCLUSIONS: The results of this finite element analysis indicated that BD models showed lower maximum von Mises stress values than the MTA models, and SPs exposed higher stress concentrations in root perforation regions than FPs and PDPs. The use of MTA and BD may reduce the risk of potentially harmful stress in root perforation regions.
Assuntos
Compostos de Cálcio , Silicatos , Compostos de Alumínio/uso terapêutico , Compostos de Cálcio/efeitos adversos , Combinação de Medicamentos , Análise de Elementos Finitos , França , Humanos , Doença Iatrogênica , Dente Molar/diagnóstico por imagem , Dente Molar/cirurgia , Óxidos/efeitos adversos , Silicatos/uso terapêuticoRESUMO
OBJECTIVE: The aim of this study was to compare the accuracy of three electronic apex locators (EALs) (Propex Pixi, Mini Root ZX, Raypex 5) in determining working length (WL) under different environments (existence of blood-pulp/sodium hypochlorite in root canal space) using micro-computed tomography (micro-CT) measurements. METHODS: Twenty-five single-rooted human teeth that were scheduled for extraction were selected for the study. Measurements were performed with the Propex Pixi, Mini Root ZX, Raypex 5 in vivo conditions in the presence of NaOCl irrigant solution or blood-pulp tissue. After that the teeth were extracted and scanned using micro-CT. The measurements of WL obtained with the different EALs in different environments were statistically compared. Signiï¬cance was set at P<0.05. RESULTS: There were no significant differences among the WL measurements performed with EALs or micro CT groups under different clinical enviroments. All EALs tested gave reliable results in respect to apical constriction. CONCLUSION: The accuracy of the tested EALs is not affected by pulp tissues and blood or NaOCl.
Assuntos
Preparo de Canal Radicular , Ápice Dentário , Eletrônica , Humanos , Odontometria , Ápice Dentário/diagnóstico por imagem , Microtomografia por Raio-XRESUMO
The aim of this study was to evaluate the stresses within simulated roots with internal resorption cavities at the apical, middle and coronal root levels, after obturation with gutta-percha and/or MTA utilising finite element analysis (FEA). Mandibular premolar teeth with internal resorption cavities at different root levels were modelled. Models were restored with gutta-percha and/or MTA. An oblique force of 300 N was applied and stress evaluations were carried out. In the MTA-filled resorption models, the stresses were distributed more homogeneously than the gutta-percha filled models, and the stress concentrations were lower in the remaining dentinal tissues. If the whole root is considered, the fully gutta-percha-filled models generated the highest stress values. Differences between the fully MTA-filled models and hybrid techniques were present only in the apical resorption models. Both the MTA and combination of MTA and gutta-percha can be suggested for use in clinical practice, in cases of internal root resorption cavity obturation.
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Materiais Restauradores do Canal Radicular , Compostos de Alumínio , Dente Pré-Molar , Compostos de Cálcio , Combinação de Medicamentos , Análise de Elementos Finitos , Guta-Percha , Óxidos , Obturação do Canal Radicular , SilicatosRESUMO
PURPOSE: To determine the effects of two different sterilization methods on the pull-out bond strength, flexural strength, and elastic modulus of glass-fiber posts. MATERIALS AND METHODS: A total of 69 glass-fiber posts were used. The posts were divided into three groups according to applied sterilization method: 1) control, 2) ethylene oxide gas (EOG), and 3) autoclave. The microstructure of three posts from each group was evaluated by SEM and energy-dispersive X-ray spectroscopy (EDS). Thirty glass-fiber posts were used to evaluate pull-out bond strength. The three-point bending test was performed to analyze the flexural strength on another 30 glass-fiber posts. Failure modes were categorized microscopically after the pull-out test. After the three-point bending test, micromorphology at the bending area was examined using SEM. RESULTS: One-way ANOVA indicated no statistically significant differences among the group means in terms of bond strength (p > 0.05), flexural strength (p > 0.05), or elastic modulus (p > 0.05). EDS revealed that the weight percentage of surface oxygen atoms in the EOG- and autoclave-sterilization groups were significantly higher. SEM images were similar. CONCLUSION: The results of this study show that glass-fiber posts can be sterilized either by autoclave or EOG when necessary, without any negative effect on bond strength, flexural strength, or elastic modulus.
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Técnica para Retentor Intrarradicular , Materiais Dentários , Análise do Estresse Dentário , Vidro , Teste de Materiais , Esterilização , Propriedades de SuperfícieRESUMO
PURPOSE: The aim of this study was to test the null hypothesis that no difference exists between shear bond strength values of control and bleaching plus desensitizer applied groups. MATERIALS AND METHODS: A hundred freshly extracted human premolar teeth were randomly divided into five groups. Group I served as the control group with no bleaching application, while only bleaching was achieved in Group II. Desensitizer containing potassium nitrate-fluoride and casein phosphopeptide amorphous calcium phosphate were applied in Groups III and IV, after bleaching respectively. A bleaching agent containing amorphous calcium phosphate was used in Group V. Shear bond strength tests were carried out using a universal testing machine (Instron Corp., Norwood, MA, USA). Remnant adhesive on the teeth and brackets was examined to score the adhesive remnant index. Kruskal-Wallis and Chi-Square tests were used for statistical analysis of the data. RESULTS: Statistically significant differences were found among the groups for shear bond strength values (p<.001). The shear bond strength of Group III (8.0±2.2 MPa) was significantly lower than the other groups (p<.05). The highest shear bond strength values were found for Group I (13.6±3.7 MPa) and Group IV (12.8±4.0 MPa). No statistically significant difference was observed between Group II (10.0±2.7 MPa) and Group V (10.8±2.9 MPa). The differences between adhesive remnant index scores of the groups were not statistically significant. CONCLUSION: Casein phosphopeptide amorphous calcium phosphate gel application showed a similar shear bond strength value to the control group, while shear bond strength values decreased after using other desensitizers.
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The aim of this report is to present a combined treatment approach with gingivectomy and CO2 laser for the management of cyclosporine-induced gingival overgrowth in 4 cases. Four renal transplant patients were surgically treated for marked gingival overgrowth by means of gingivectomy and CO2 laser. Postoperatively, all patients were followed for bleeding, pain, infection during the early healing period, and recurrence of gingival overgrowth for 12 months. The healing was uneventful, and no signs of bleeding, postoperative pain, or infection were observed in any patient during the early healing period. In the 12th postoperative month, there was evidence of mild recurrence in 1 patient, while no sign of recurrence was observed in the other patients during the follow-up period. The advantages of this combined technique include satisfactory bleeding control and clear visibility during the procedure, as well as reduced postoperative pain and swelling.