Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 53
Filtrar
1.
J Clin Med ; 9(11)2020 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-33228002

RESUMO

This study aimed to evaluate one-year radiographic healing after endodontic microsurgery using CBCT with modified PENN 3D criteria and to compare the outcome with results evaluated using Molven's criteria. A total of 107 teeth from 96 patients were evaluated one year after endodontic microsurgery by using CBCT scans with modified PENN 3D criteria and periapical radiographs with Molven's criteria. Both preoperative and postoperative lesion volumes were calculated using ITK-SNAP (free software). Radiographic healing assessment using periapical radiographs and CBCT images, and preoperative and postoperative lesion volume measurements were performed independently by two examiners. The assessment using Molven's criteria resulted in 75 complete healings, 18 incomplete healings, eight uncertain healings, and six unsatisfactory healings. Based on modified PENN 3D criteria, 64 teeth were categorized as complete healing, 29 teeth as limited healing, six teeth as uncertain healing, and eight teeth as unsatisfactory healing. With the one-year follow-up, CBCT scans showed a lower healing tendency than did periapical radiography. The volumes of apical radiolucency after the surgery were reduced by 77.7% on average at one-year follow up.

2.
Materials (Basel) ; 13(22)2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33233519

RESUMO

The aim of this study was to evaluate the biocompatibility of calcium silicate-based sealers (CeraSeal and EndoSeal TCS) and epoxy resin-based sealer (AH-Plus) in terms of cell viability, inflammatory response, expression of mesenchymal phenotype, osteogenic potential, cell attachment, and morphology, of human periodontal ligament stem cells (hPDLSCs). hPDLSCs were acquired from the premolars (n = 4) of four subjects, whose ages extended from 16 to 24 years of age. Flow cytometry analysis showed stemness of hPDLSCs was maintained in all materials. In cell viability test, AH-Plus showed the lowest cell viability, and CeraSeal showed significantly higher cell viability than others. In ELISA test, AH-Plus showed higher expression of IL-6 and IL-8 than calcium silicate-based sealers. In an osteogenic potential test, AH-Plus showed a lower expression level than other material; however, EndoSeal TCS showed a better expression level than others. All experiments were repeated at least three times per cell line. Scanning electronic microscopy studies showed low degree of cell proliferation on AH-Plus, and high degree of cell proliferation on calcium silicate-based sealers. In this study, calcium silicate-based sealers appear to be more biocompatible and less cytotoxic than epoxy-resin based sealers.

3.
Restor Dent Endod ; 45(3): e27, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32839708

RESUMO

Apical surgery for a mandibular molar is still challenging for many reasons. This report describes the applications of computer-guided cortical 'bone-window technique' using piezoelectric saws that prevented any nerve damage in performing endodontic microsurgery of a mandibular molar. A 49-year-old woman presented with gumboil on tooth #36 (previously endodontically treated tooth) and was diagnosed with chronic apical abscess. Periapical lesions were confirmed using cone-beam computed tomography (CBCT). Endodontic microsurgery for the mesial and distal roots of tooth #36 was planned. Following the transfer of data of the CBCT images and the scanned cast to an implant surgical planning program, data from both devices were merged. A surgical stent was designed, on the superimposed three-dimensional model, to guide the preparation of a cortical window on the buccal side of tooth #36. Endodontic microsurgery was performed with a printed surgical template. Minimal osteotomy was required and preservation of the buccal cortical plate rendered this endodontic surgery less traumatic. No postoperative complications such as mental nerve damage were reported. Window technique guided by a computer-aided design/computer-aided manufacture based surgical template can be considerably useful in endodontic microsurgery in complicated cases.

4.
Restor Dent Endod ; 45(2): e4, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32483529

RESUMO

Although numerous studies have been conducted on apexification using mineral trioxide aggregate (MTA), direct observation of extracted human teeth after the procedure has been rarely reported. This case report describes a mandibular premolar treated 2.5 years ago and extracted recently for orthodontic treatment. The tubercle of the right mandibular premolar of a 12-year-old boy with dens evaginatus was fractured and the pulp was exposed. The tooth was diagnosed with pulp necrosis and asymptomatic periapical abscess. During the first visit, copious irrigation was performed with 2.5% sodium hypochlorite. Calcium hydroxide paste was placed as an intracanal medicament. The sinus tract had disappeared at the second visit after 3 weeks. MTA was applied on to the bleeding point as a 4-mm-thick layer, followed by a 3-mm-thick gutta-percha filling and resin core build-up. After 2.5 years, the tooth and three other premolars were extracted for orthodontic treatment. The right and left mandibular premolars were scanned with micro-computed tomography to determine the root shape and canal anatomy. Irregular root growth was observed and the root outline of the right mandibular premolar differed from that of the contralateral tooth. Apexification with MTA leads to the formation of roots with irregular morphology, without any pulpal space.

5.
J Endod ; 46(4): 539-544, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32067720

RESUMO

INTRODUCTION: The aim of this study was to investigate the influence of apical filling material and the modification made to the apical preparation design in surgical endodontics on the areas of stress concentration in the mesial root of a mandibular molar using finite element analysis. METHODS: The filling material was injected under 2 conditions (ie, with or without mineral trioxide aggregate retrograde filling). The apical preparation design was modified by extending the preparation mesially while maintaining a similar prepared area. We contained the displacement of all the nodes at the base of the supporting bone and applied a force of 150 N to the vertical axis. We analyzed stress generation and concentrations numerically for all cavity design groups. RESULTS: In the presence of retrograde filling, the von Mises stress decreased gradually according to the enlargement of the prepared cavity in the subgroups. When the retrograde filling was absent, the von Mises stress increased as the prepared cavity enlarged. The modification of the apical preparation extending in the mesial direction showed a drastic decrease in stress concentration. CONCLUSIONS: Within the limitations of this study, it was advantageous to perform mesial retrograde preparation within the mesial root dentin to maintain a balanced root dentin on both sides of the apical preparation and create a low-stress field. The surgeon should be careful not to wash out or dislodge the retrograde filling material during obturation to avoid failure of surgery.


Assuntos
Endodontia , Dente Molar , Preparo da Cavidade Dentária , Análise de Elementos Finitos , Raiz Dentária
6.
Sci Rep ; 10(1): 1247, 2020 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-31988399

RESUMO

The purpose of this study was to evaluate the incidence and microscopic anatomy of the isthmus to provide more precise anatomical information about the mesiobuccal (MB) roots of the maxillary first molars and the mesial (M) roots of the mandibular first molars. Twenty-eight maxillary and 31 mandibular first molars were embedded, sectioned, stained, and observed at 30× magnification to evaluate the incidence and microscopic anatomy of the isthmus. The incidence of an isthmus 3 mm from the apex was 89.3% and 100% in the MB roots of the maxillary first molars and in the M roots of the mandibular first molars, respectively. The mean dentin thickness between the isthmus and the distal root surface was <1 mm at a distance of 3 mm from the apex in both types of roots. In this study, whenever two main canals were located in the MB roots of the maxillary first molars and in the M roots of the mandibular first molars, the likelihood of the presence of an isthmus increased. Therefore, clinicians should be aware of the thinnest dimensions in the distal surface of the MB roots of the maxillary first molars and the M roots of the mandibular first molars during nonsurgical and surgical root canal treatment.


Assuntos
Cavidade Pulpar/anatomia & histologia , Dente Molar/anatomia & histologia , Raiz Dentária/anatomia & histologia , Adulto , Dentina/anatomia & histologia , Feminino , Humanos , Masculino , Microscopia/métodos , Odontometria , República da Coreia/epidemiologia , Ápice Dentário/anatomia & histologia
7.
BMC Oral Health ; 20(1): 23, 2020 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-31996198

RESUMO

BACKGROUND: This study, by using a variable-controlled survey model, sought to compare clinical decisions made by dentists with different clinical backgrounds in South Korea regarding teeth with apical periodontitis and to identify factors that influenced decision-making. METHODS: A questionnaire with 36 questions about identical patient information, clinical signs, and symptoms was filled out by participants. Each question referred to a radiograph that had been manipulated using computer software in order to control tooth-related factors. Participants were instructed to record their demographic information and choose the ideal treatment option related to each radiograph. Simple and multivariable logistic regression analyses (p < .05) were used to investigate factors related to the decision to extract the tooth. We divided factors into dentist-related factors (gender, years of experience, and professional registration) and tooth-related factors (tooth position, coronal status, root canal filling status, and size of the periapical radiolucency). Dentists were categorized into three groups, based on professional registration: general dental practitioners (GDPs), endodontists, and other specialists. Simple logistic regression analysis (p < .05) was used to evaluate the tooth-related factors influencing extraction, depending on the dentists' specialty. RESULTS: Participants mostly preferred saving the teeth over extraction. This preference was highest among the endodontists, followed by other specialists and GDPs. Extractions were significantly preferred for molars, teeth with previous root canal fillings, and those with apical lesions greater than 5 mm. CONCLUSIONS: This study suggests that dentists' decision-making regarding teeth with apical periodontitis was associated with their work experience and specialty and influenced by tooth position, root canal filling status, and size of the apical lesion. CLINICAL RELEVANCE: This survey revealed that clinical decision-making related to teeth with apical periodontitis was affected by dentists' specialty and work experience and by tooth-related factors, such as tooth position, root canal filling status, and size of the apical lesion.


Assuntos
Tomada de Decisão Clínica/métodos , Odontólogos/psicologia , Periodontite Periapical , Padrões de Prática Odontológica/estatística & dados numéricos , Tratamento do Canal Radicular , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Periodontite Periapical/diagnóstico , Periodontite Periapical/terapia , República da Coreia , Inquéritos e Questionários
8.
J Endod ; 46(1): 97-102, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31759678

RESUMO

INTRODUCTION: The aim of this study was to compare the volume of voids between retrograde filling using calcium silicate cement alone and retrograde filling using a combination of calcium silicate cement with a calcium silicate-based sealer. METHODS: Twenty single-rooted, extracted human teeth were instrumented with nickel-titanium files and obturated with gutta-percha. We resected the roots at a point 3 mm from the apex, prepared the root ends, and filled the root-end cavities with Endocem Zr (Maruchi, Wonju, Korea) or Endoseal MTA (Maruchi) plus Endocem Zr. Then, we scanned the prepared samples using micro-computed tomographic imaging and performed 3-dimensional reconstruction. The percentage volume of the gap between the canal wall and root-end filling was calculated along with the percentage volume of voids in the filling materials. All data were analyzed using the Mann-Whitney U test. Selected specimens were further observed using scanning electron microscopy. RESULTS: There were no significant differences in the percentage volumes of the gaps and internal voids between the 2 groups. Both calcium silicate and the calcium silicate-based sealer exhibited good adaptation to the cavity wall. CONCLUSIONS: The findings of our micro-computed tomographic and scanning electron microscopic analyses suggested that the volume of voids in retrograde filling using a combination of calcium silicate cement and calcium silicate-based sealer was comparable with that in retrograde filling using calcium silicate cement only. Calcium silicate-based sealers could be used in retrograde filling for clinical convenience without harmful effects on the quality of filling.


Assuntos
Compostos de Cálcio , Materiais Restauradores do Canal Radicular , Cimento de Silicato , Silicatos , Cálcio , Cavidade Pulpar , Guta-Percha , Humanos , Teste de Materiais , Obturação do Canal Radicular
9.
Clin Oral Investig ; 24(1): 247-255, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31081517

RESUMO

OBJECTIVES: The purpose of this retrospective study was to evaluate and compare the effects of fast- and slow-setting calcium silicate-based materials (CSMs) used for root-end filling on the outcome of endodontic microsurgery. MATERIALS AND METHODS: We searched a clinical database for patients who had received endodontic microsurgery between 2001 and 2016. Included cases were divided into two groups according to the type of CSM used for root-end filling: slow-setting CSM (SCSM) and fast-setting CSM (FCSM). The cases in two groups were subjected to 1:1 nearest neighbor propensity score matching for the following variables: age, sex, tooth type, quality of canal filling, lesion type, and postoperative restoration. For each matched case, the outcome was determined as success or failure according to clinical and radiographic evaluations performed at least 1 year after surgery. Multivariate logistic regression analysis was performed to identify prognostic factors and estimate their effects. RESULTS: In total, 304 cases of endodontic microsurgery (179 SCSM and 125 FCSM) were identified, and 1:1 propensity score matching finally included 122 cases from each group. After matching, all covariates were associated with an absolute standardized difference of < 0.1. The overall success rates were 85.2% and 93.4% for the SCSM and FCSM groups, respectively (p = 0.062). Age, tooth type, lesion type, and CSM type were significantly associated with the outcome of endodontic microsurgery (p < 0.05). CONCLUSIONS: Within the limitations, the outcome of endodontic microsurgery using FCSMs was comparable with that of SCSMs. The findings suggest that the type of CSM used for root-end filling, particularly in terms of the initial setting time, could affect the outcome of endodontic microsurgery. CLINICAL RELEVANCE: FCSMs could be considered for use as root-end filling materials in endodontic microsurgery, particularly in complicated clinical situations which require rapid initial setting of the materials.


Assuntos
Compostos de Cálcio , Microcirurgia , Materiais Restauradores do Canal Radicular , Silicatos , Cálcio , Compostos de Cálcio/farmacologia , Feminino , Humanos , Masculino , Estudos Retrospectivos , Tratamento do Canal Radicular , Silicatos/farmacologia , Resultado do Tratamento
10.
J Endod ; 45(10): 1192-1199, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31439355

RESUMO

INTRODUCTION: The purpose of the current population-based study was to analyze the 5-year survival rate of teeth that received nonsurgical endodontic treatment. Specifically, the variables affecting the 5-year survival rates of endodontically treated teeth were analyzed. METHODS: The present study included all endodontically treated teeth reported in 2010 in the National Health Insurance Cohort database of the Republic of Korea. By tracing the dental records of the sample to the end of 2015, the 5-year survival rates of the initial root canal treatment (RCT) and re-RCT were analyzed. Gender, age, institution type, diagnosis, arch type, tooth type, number of visits, and rubber dam usage were included in the analyses as confounding variables. RESULTS: In total, 2,866,749 teeth received initial RCT, and 173,429 teeth received re-RCT. Five-year survival rates were 90.85% and 88.42%, respectively. The survival rate of teeth that received initial RCT was significantly higher than that of those that received re-RCT. Specifically, re-RCT showed a significantly higher rate of extraction within 12 months than during other intervals. Furthermore, the following characteristics significantly positively affected the 5-year tooth survival rate: being female, <20 years of age, hospital as the institution type, mandibular teeth, anterior teeth, initial RCT, and use of rubber dam. CONCLUSIONS: Because of its high 5-year survival rate, endodontic treatment is an effective method for maintaining natural teeth.


Assuntos
Tratamento do Canal Radicular , Adolescente , Adulto , Estudos de Coortes , Feminino , Humanos , Masculino , República da Coreia , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
11.
J Clin Med ; 8(8)2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-31426363

RESUMO

Trauma or injury to the dental pulp causes inflammation. This study compared the proteome of healthy pulp with inflamed pulp and traumatic pulp to identify the differentially expressed proteins in the diseased state. Five participants were grouped based on the pulpal status of the teeth: healthy, inflamed, or traumatic pulp. Pulp was extirpated and stored immediately in liquid nitrogen. Pulp tissues were subjected to 2-dimensional gel electrophoresis, and spot selection was performed. The selected spots were analyzed using liquid chromatography-tandem mass spectrometry and identified by correlating mass spectra to the proteomic databases. Fifteen spots showed increased expression in the inflamed and traumatic pulp. Annexin V, type II keratin, and hemoglobin levels were increased two-fold in the inflamed and traumatic pulp group and annexin V, mutant beta-actin, and hemoglobin were increased by ten-fold in the inflamed or traumatic pulp group, compared to levels in the healthy pulp group. Annexin V constituted two out of fifteen protein spots, and seemed to play a critical role in inhibiting inflammation and promoting the immune reaction. Further studies on this protein concerning its role in pulp repair are necessary to elucidate the underlying mechanisms.

12.
Materials (Basel) ; 12(15)2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31362338

RESUMO

The aim of this study was to assess the effect of three calcium silicate-based sealers (EndoSeal MTA, Nano-ceramic Sealer, and Wellroot ST) and two epoxy resin-based sealers (AH-Plus, AD Seal) on various aspects, such as cell viability, inflammatory response, and osteogenic potential, of human periodontal ligament stem cells (hPDLSCs). AH-Plus showed the lowest cell viability on hPDLSCs in all time periods in fresh media. In set media, hPDLSCs showed no significant differences in cell viability among all the tested materials. Wellroot ST showed the highest level of cell adhesion and the morphology of attached cells. AH-plus presented a significantly higher expression of IL-6 and IL-8 than the other sealers. AD Seal and three calcium silicate sealers showed high expression of the mesenchymal stem cell markers. ALP mRNA expression showed a significant increase in time-dependent manner on all of three calcium silicate-based sealers, which do not seem to interfere with the differentiation of hPDLSCs into osteoblasts. Based on the results from this study, calcium silicate-based sealers appear to be more biocompatible and less cytotoxic than epoxy resin-based sealers. Meanwhile, further and long-term clinical follow-up studies are required.

13.
J Clin Med ; 8(7)2019 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-31284630

RESUMO

This study aimed to assess the efficacy of canal filling material removal using three different techniques after filling with a Gutta-Percha (GP) cone and calcium silicate-based sealer, by measuring the percentage of volume debris of GP and sealer remaining intracanal with micro computed tomography (micro-CT). The filling material was removed from 30 plastic teeth by a nickel-titanium (Ni-Ti) rotary retreatment system. Final irrigation was performed with 2 mL of saline and 10 specimens were randomly allocated to a conventional group. In the passive ultrasonic irrigation (PUI) group, ultrasonic irrigation was added to the conventional group (n = 10). In the Gentlefile Brush (GF Brush) group, irrigation with GF Brush was added to the conventional group (n = 10). Remaining filling material was measured using micro-CT imaging analysis. The total mean volume of residual filling material after retreatment in the conventional group, PUI group and GF Brush group were 4.84896 mm3, 0.80702 mm3, and 0.05248 mm3, respectively. The percentage of filling material remaining intracanal was 6.76% in the conventional group, 1.12% in the PUI group and 0.07% in the GF Brush group. This study shows that the cleaning effect of the GF Brush system is superior to those of Ni-Ti retreatment files and the PUI system in the apical area.

14.
Restor Dent Endod ; 44(2): e20, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31149618

RESUMO

Objectives: To achieve pulp-dentin complex regeneration with tissue engineering, treatment efficacies and safeties should be evaluated using in vivo orthotopic transplantation in a sufficient number of animals. Mice have been a species of choice in which to study stem cell biology in mammals. However, most pulp-dentin complex regeneration studies have used large animals because the mouse tooth is too small. The purpose of this study was to demonstrate the utility of the mouse tooth as a transplantation model for pulp-dentin complex regeneration research. Materials and Methods: Experiments were performed using 7-week-old male Institute of Cancer Research (ICR) mice; a total of 35 mice had their pulp exposed, and 5 mice each were sacrificed at 1, 2, 4, 7, 9, 12 and 14 days after pulp exposure. After decalcification in 5% ethylenediaminetetraacetic acid, the samples were embedded and cut with a microtome and then stained with hematoxylin and eosin. Slides were observed under a high-magnification light microscope. Results: Until 1 week postoperatively, the tissue below the pulp chamber orifice appeared normal. The remaining coronal portion of the pulp tissue was inflammatory and necrotic. After 1 week postoperatively, inflammation and necrosis were apparent in the root canals inferior to the orifices. The specimens obtained after experimental day 14 showed necrosis of all tissue in the root canals. Conclusions: This study could provide opportunities for researchers performing in vivo orthotopic transplantation experiments with mice.

15.
Materials (Basel) ; 12(8)2019 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-30999582

RESUMO

This study aimed to analyze the effects of different calcium silicate cements (CSCs) on the inflammatory response and odontogenic differentiation of lipopolysaccharide-stimulated human dental pulp stem cells. Human dental pulp stem cells (hDPSCs) were stimulated with lipopolysaccharide (LPS) to induce inflammation. These LPS-induced dental pulp stem cells (LDPSCs) were cultured with ProRoot MTA, Biodentine, Retro MTA, and Dycal. Cell viability was evaluated using the Cell Counting Kit-8 assay. Interleukin (IL)-6, IL-8, and transforming growth factor (TGF)-ß1 cytokine levels were assessed using the enzyme-linked immunosorbent assay. The expressions of alkaline phosphatase (ALP), osteocalcin, and runt-related transcription factor 2 (RUNX2) were analyzed through real-time polymerase chain reaction. ProRoot MTA, Biodentine, and Retro MTA did not significantly decrease the cell viability of LDPSCs for up to 48 h (p < 0.05). Retro MTA significantly decreased the expression of IL-6 and IL-8 by LDPSCs. ProRoot MTA and Biodentine significantly reduced TGF-ß expression by LDPSCs (p < 0.05). Regarding odontogenic differentiation, all CSCs had no effect on ALP expression but increased the production of RUNX2 at 12 h.

16.
J Endod ; 45(4): 442-446, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30827768

RESUMO

INTRODUCTION: The aim of this study was to investigate the influence of various apical preparation designs for surgical endodontics on stress concentrations in the mesial root of the mandibular molar under different experimental conditions using finite element analysis. METHODS: We designed 2 apical preparation groups according to whether an isthmus was present or not. Each group contained 4 subgroups according to the size of the apical preparation. We constrained the displacement of all nodes at the base of the supporting bone and applied a force of 150 N to the vertical axis. We analyzed stress generation and concentrations numerically for the groups and subgroups. RESULTS: In the subgroups, the von Mises and maximum principal stresses reduced gradually according to the enlargement of the prepared cavity. However, when the preparation extended excessively in the isthmus preparation groups, the situation reversed (ie, both von Mises and maximum principal stresses increased). CONCLUSIONS: Within the limitations of this study, the apical preparation design influenced the distribution of stress concentration. Unlike the overall pattern in which stress decreased as the amount of apical preparation increased, stress increased when the amount of residual dentin was extremely thin.


Assuntos
Preparo da Cavidade Dentária/métodos , Análise do Estresse Dentário , Endodontia , Análise de Elementos Finitos , Mandíbula , Dente Molar , Estresse Mecânico , Raiz Dentária , Modelos Dentários , Dentina/anatomia & histologia , Dentina/patologia , Dentina/cirurgia , Humanos , Raiz Dentária/anatomia & histologia , Raiz Dentária/patologia , Raiz Dentária/cirurgia
17.
J Endod ; 44(11): 1632-1640, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30243664

RESUMO

INTRODUCTION: The purpose of this retrospective study was to evaluate and compare the outcome of endodontic micro-resurgery with that of primary endodontic microsurgery and determine prognostic factors affecting the outcome of micro-resurgery. METHODS: A clinical database was searched for endodontic microsurgery cases between 2001 and 2016. Nearest neighbor 2:1 propensity score matching for the following 5 variables was performed for cases of primary microsurgery and those of micro-resurgery: age, sex, tooth type, lesion type, and postoperative restoration. For the matched cases, the outcome was categorized as success or failure according to clinical and radiographic evaluations performed at least 1 year after surgery. Kaplan-Meier survival analysis and log-rank tests were performed to compare the outcome of primary microsurgery with that of micro-resurgery over time. For the micro-resurgery group, multivariate Cox proportional hazard regression analysis was performed to identify prognostic factors and estimate their effects. RESULTS: In total, 571 cases of endodontic microsurgery (498 primary microsurgery and 73 micro-resurgery cases) were identified, and 146 cases of primary microsurgery were matched to 73 cases of micro-resurgery through 2:1 propensity score matching. After matching, all covariates demonstrated an absolute standardized difference of <0.1. The estimated 5-year success rates were 91.6% and 87.6% for primary microsurgery and micro-resurgery, respectively (P = .594). The tooth type was found to be the only contributing factor for the outcome of micro-resurgery, with molars showing a higher probability of failure than anterior teeth (hazard ratio, 8.53; P = .002). CONCLUSIONS: Within the limitations, the findings of this study suggest that the outcome of endodontic micro-resurgery is comparable with that of primary endodontic microsurgery.


Assuntos
Endodontia/métodos , Microcirurgia/métodos , Pontuação de Propensão , Adulto , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Resultado do Tratamento
18.
Appl Opt ; 57(18): 5090-5094, 2018 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-30117970

RESUMO

Highly efficient transmission-type beam deflectors that have high angular resolution have been widely used for various applications. Continuously tunable beam deflectors have also been needed for many purposes. An indium-tin-oxide (ITO), widely used for transparent electrodes, was placed on the upper and lower glass substrate. The ITO layer on the lower substrate was patterned by the contact mask aligner for relatively wide input and output pad compared to main grating ITO patterns in the active area. These input and output pads on the lower substrate are connected to each driving integrated circuit (IC), which has 360 channels for continuous control. A small pixel pitch of grating patterns of 6 µm (the electrode width is 3 µm with a 3 µm spacing) was developed, and the maximum diffraction angle is calculated and measured at 2.541° with a wavelength of 532 nm. A minimal cell gap of 2.5 µm was applied for the full 2π phase modulation by using a high-birefringence liquid crystal. A driving module for continuous beam steering is also developed and applied to the beam deflector system. A diffraction efficiency of about 50.9% is observed at an angle of diffraction about 2.541°.

19.
Scanning ; 2018: 7136345, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29576841

RESUMO

Objective: To investigate the effect of different setting conditions on surface microhardness and setting properties of calcium silicate-based sealers. Methods: Three sealers, EndoSequence Bioceramic (BC; Brasseler USA, Savannah, GA, USA), Endoseal MTA (ES; Maruchi, Wonju, Korea), and Well-Root ST (WR; Vericom, Chuncheon, Korea), were compared. Specimens were exposed to either butyric acid (pH 5.4) or phosphate-buffered saline (PBS [pH 7.4]) for 48 h and stored at 100% humidity for 12 days. The control specimens were stored at 100% humidity for 14 days. Surface microhardness was measured, topographic changes were observed, and phase analysis was performed using X-ray diffraction. Microhardness according to storage conditions was compared using one-way analysis of variance and Tukey's multiple comparison tests (P < .05). Results: The BC and ES sealers exhibited decreased microhardness when stored in acid or PBS compared with control (P < .05). In the WR group, acid exposure lowered microhardness of the specimens compared with control (P < .05). Scanning electron microscopy revealed different topographies in specimens from all tested sealers exposed to acid or PBS. Conclusion: The surface microhardness of calcium silicate-based sealers was reduced by exposure to either acid or PBS. Acid solutions, however, had a more detrimental effect than PBS.

20.
J Endod ; 44(4): 592-598, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29370943

RESUMO

INTRODUCTION: Several studies have attempted to use human dental pulp stem cells (hDPSCs) for pulp-dentin complex regeneration in vitro. However, the safety of such applications should be first evaluated in vivo before their use in clinical trials. The purpose of this study was to investigate the in vivo fate of intrapulpally transplanted hDPSCs. METHODS: hDPSCs were isolated and cultured from impacted third molars. In vivo experiments were performed using 7-week-old male BALB/c nude mice. Under deep anesthesia, 1 × 105 hDPSCs were transplanted in mice via the tail vein for intravenous injection or into the pulp chamber for intrapulpal transplantation. A total of 56 mice, 28 per group, were used. Mice were sacrificed at different time points, and the numbers of hDPSCs in the organs were analyzed quantitatively. In addition, qualitative analysis was performed to detect intrapulpally transplanted hDPSCs. RESULTS: Intravenously injected hDPSCs were mostly distributed to the lungs and rarely detected in other organs at all observed time points. The hDPSCs transplanted into the pulp chamber rarely migrated to other organs over time. CONCLUSIONS: These data indicate a differential distribution of transplanted hDPSCs between the intravenous and intrapulpal route and show the safety of pulpal transplantation of hDPSCs.


Assuntos
Polpa Dentária/transplante , Transplante de Células-Tronco , Animais , Movimento Celular , Polpa Dentária/citologia , Imunofluorescência , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Transplante de Células-Tronco/métodos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...