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1.
Eur J Dent Educ ; 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33386660

RESUMO

INTRODUCTION: Due to COVID-19, innovative, virtual educational methods are being developed to provide students with learning experiences comparable to established clinical practices. Our objective was to produce the Periodontal Senior Case Clinical Challenge (PSCCC) that would provide fourth-year students an alternative for senior case presentations and would be a formative assessment for which student opinions would be provided and analysed. The PSCCC would utilise an online, case-based, written, clinical assessment and follow-up, structured discussion to challenge students to demonstrate ability to apply didactic periodontal knowledge to patient-based experiences. We hypothesised the PSCCC would provide effective learning and a formative assessment. MATERIAL AND METHODS: Relevant didactic resources were distributed to 48 students for independent review. The PSCCC was delivered in two sections, (1) a case-based assessment via a virtual classroom with written student responses, and (2) oral discussions conducted via virtual meetings that were moderated and assessed by ten periodontists, with the collaboration of nine residents. A voluntary six-statement survey was used to evaluate the students' opinions of the PSCCC. The scores for 75% (36/48) of students who participated were evaluated for statistical and clinical importance. RESULTS: The value of our PSCCC was supported by 91.7% (33/36) of the analyses (p < .0008). DISCUSSION: The PSCCC was a successful alternative pathway to assess students' clinical and didactic integrated knowledge in periodontics. It provided a unified vision of treatment of the selected case, building on all aspects of the students' periodontal education whilst allowing interaction in a simultaneous, three-tiered educational approach, involving dental students, periodontal residents and faculty. CONCLUSION: In support of our hypothesis, for each of the 6 statements, ≥94.44% (34/36) of the scores given by the students were considered exceptionally strong clinical support for our pedagogical strategy that combines educational resources and can be successfully implemented in other programmes.

2.
Artigo em Inglês | MEDLINE | ID: mdl-33114133

RESUMO

Dental implant abutment and prosthetic materials, their surface treatment, and cleaning modalities are important factors for the formation of a peri-implant soft tissue seal and long-term stability of bone around the implant. This study aimed to investigate the influence of a polymeric material surface cleaning method on the surface roughness, water contact angle, and human gingival fibroblasts (HGF) proliferation. Polymeric materials tested: two types of milled polymethylmethacrylate (PMMA-Ker and PMMA-Bre), three-dimensionally (3D) printed polymethylmethacrylate (PMMA-3D), polyetheretherketone (PEEK), and polyetherketoneketone (PEKK). Titanium (Ti) and zirconia oxide ceramics (ZrO-HT) were used as positive controls. A conventional surface cleaning protocol (CCP) was compared to a multi-step research cleaning method (RCP). Application of the RCP method allowed to reduce Sa values in all groups from 0.14-0.28 µm to 0.08-0.17 µm (p < 0.05 in PMMA-Ker and PEEK groups). Moreover, the water contact angle increased in all groups from 74-91° to 83-101° (p < 0.05 in the PEKK group), except ZrO-HT-it was reduced from 98.7 ± 4.5° to 69.9 ± 6.4° (p < 0.05). CCP resulted in higher variability of HGF viability after 48 and 72 h. RCP application led to higher HGF viability in PMMA-3D and PEKK groups after 48 h, but lower for the PMMA-Ker group (p < 0.05). After 72 h, no significant differences in HGF viability between both cleaning methods were observed. It can be concluded that the cleaning method of the polymeric materials affected surface roughness, contact angle, and HGF viability at 48 h.

3.
Oral Health Prev Dent ; 18(1): 373-378, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31624810

RESUMO

PURPOSE: To identify the prevalence and determinants of dental trauma in permanent anterior teeth among 11- to 13-year-old schoolchildren, to compare self-reported dental trauma rates with clinical examination trauma rates, and to examine mouthguard use among children engaged in contact sports. MATERIALS AND METHODS: A probability sampling scheme was used to recruit schools, with all 6th grade children in the selected schools invited to participate. A total of 2621 caregiver consent forms were sent, of which 807 were returned (31%). Caregivers were asked four trauma-related questions. Clinical examinations included assessment of dental trauma experience (trauma index with five severity codes), lip competence and incisal overjet. Child- and tooth-level analyses were performed. RESULTS: Clinical evidence of dental trauma was found in 52% of participants, 13% self-reported dental trauma, and 7% of children did not remember the occurrence of any trauma. The two most frequently self-reported reasons of dental injury were falls or collisions with objects (63%) and sport/leisure activities (32%). Nearly half of the more severe dental injuries did not receive the necessary treatments. One-third of schoolchildren participated in contact sport activities, but only 3% always used mouthguards. There was a substantial difference between the clinical and self-reported findings. Logistic regression analyses revealed no statistically significant associations between dental trauma experience and the potential determinants studied: gender, lip coverage and overjet. CONCLUSION: In this study, traumatic dental injuries were observed with 52% prevalence. A substantial discrepancy between self-reported and clinical findings was observed.


Assuntos
Traumatismos em Atletas , Sobremordida , Traumatismos Dentários , Adolescente , Atitude , Criança , Estudos Transversais , Dentição Permanente , Humanos , Prevalência
4.
Materials (Basel) ; 12(11)2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31141936

RESUMO

The present study evaluated the porosity distribution of BioRoot RCS/single gutta-percha point (BR/SC) and MTA flow (MF) fillings, which were used as plugs for the apical perforation repair in curved canals of extracted mandibular molars using micro-computed tomography (µCT). Forty mesial root canals of mandibular first molars were shaped with ProTaper NEXT X1-X5 files 2 mm beyond the apex to simulate apical perforations that were randomly divided into two groups (n = 20) according to the material and technique used for the apical plug: BR/SC or MF. The specimens were scanned before and after canal filling at an isotropic resolution of 9.9 µm. The volumetric analysis of voids in the apical 5 mm of the fillings was performed. Data were analyzed using one-way ANOVA with Bonferroni correction (p < 0.05). Micro-computed tomography (µCT) evaluation revealed significant differences between the groups in terms of porosity: the total volume and percentage volume of voids was lower in the BR/SC group in comparison with the MF group (p < 0.05), with the predominance of open pores in both groups. Neither of the materials and/or application techniques were able to produce void-free root fillings in the apical region of artificially perforated curved roots of mandibular molars.

5.
Medicina (Kaunas) ; 53(3): 166-172, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28669594

RESUMO

OBJECTIVE: The aim of this study was to compare the impact of treatment procedures on roots previously treated with resorcinol-formaldehyde resin and analyze the effectiveness of dye and magnification for the detection of dentin cracks. MATERIALS AND METHODS: Distal roots of 80 permanent first mandibular molars with a single canal were sectioned at 3mm and 9mm from the anatomical apex. Two groups were formed according to the method used for root canal penetration: group 1 (K-file and Pro Taper instruments) and group 2 (Ultrasound with Pro Ultra and Pro Taper files). Before and after the completion of procedures, photographs of the roots were taken for examination for cracks or/and infraction lines with two levels of magnification and with or without a dye. RESULTS: In groups 1 and 2, either with dye or without it, there were statistically significant differences (P<0.001) with more fractures observed in the coronal than in the apical part of specimens. Statistically significant proportional differences regarding the location of fractures were observed at both magnifications. When the dye was used, there were no statistically significant differences between the two magnifications in the detection of cracks. In the specimens where the dye was not used, differences between the groups were statistically significant at both magnifications with more complete and intra-dental fractures observed in group 2. CONCLUSIONS: Retreatment methods had a damaging effect on the root dentin of teeth previously treated with resorcinol-formaldehyde resin. At magnification ×16, the efficacy of using the dye for the detection of cracks was higher than detection without the dye.


Assuntos
Fraturas dos Dentes , Humanos , Mandíbula , Retratamento , Fraturas dos Dentes/terapia
6.
Stomatologija ; 18(3): 92-97, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28386052

RESUMO

OBJECTIVE: To evaluate the root canal surfaces in teeth previously treated using RF resin by SEM. MATERIAL AND METHODS: 20 distal roots of mandibular molars with typical discoloration of tooth crown were used in this study: 10 brownish - red and 10 non-colored roots. The roots were removed from the crowns, splinted longitudinally and subjected to SEM in a back-scattered electron mode. RESULTS: In discolored root samples canal walls appeared without smear layer and varying amount of remaining debris, the observed morphology of dentine was ordinary. In the non-colored root samples the dentin profile revealed: in coronal third of the root just few open dentinal tubules were detected, while in the middle and apical thirds no open dentinal tubules were observed, dentin profile was similar to sclerotic dentin. The multiple dentinal defects were detected in all samples, however significantly more dentinal defects were found in the colored roots. The RF paste was well adhered to the root canal dentine and multiple tags of RF resin penetrating deeply into the dentinal tubules were detected. CONCLUSIONS: The surfaces of the root canal walls of the teeth treated using RF paste exhibits usual appearance and ordinary dentin morphology in colored roots while the dentin of non-colored samples has the profile of sclerotic dentin. Multiple dentinal defects could be determined by damaging effect of RF resin on dentin. The adaptation and adhesion of RF paste to the dentin, capability to penetrate into dentinal tubules is comparable with the modern resin based sealers.


Assuntos
Dentina/patologia , Formaldeído , Dente Molar/patologia , Resorcinóis , Raiz Dentária/patologia , Cor , Dentina/anatomia & histologia , Dentina/ultraestrutura , Humanos , Mandíbula , Microscopia Eletrônica de Varredura , Dente Molar/ultraestrutura , Tratamento do Canal Radicular , Camada de Esfregaço , Raiz Dentária/ultraestrutura
7.
Stomatologija ; 16(1): 7-14, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24824054

RESUMO

OBJECTIVE: . The aim was to overview the etiology, prevalence and possible outcomes of dental trauma. MATERIAL AND METHODS: An electronic search of Medline (PubMed), Cochrane, SSCI (Social Citation Index), SCI (Science Citation Index) databases from 1995 to the present, using the following search words: tooth injuries, tooth trauma, traumatized teeth, dental trauma, dentoalveolar trauma, oral trauma, epidemiology, etiology, prevalence, prevention, pulp necrosis, inflammatory resorption, ankylosis, cervical resorption, was performed. RESULTS: During last decade traumatic dental injuries were recognized as public dental health problem worldwide. Prevalence of traumatic dental injuries varies between countries. According to the existing data they are more prevalent in permanent than in primary dentition. All treatment procedures in case of dental trauma are directed to minimize undesired consequences despite that treatment of traumatic dental injuries in the young patient is often complicated and can continue during the rest of his/her life. The changing lifestyle and requirements of modern society lead to an emergence of new patterns of dental trauma. A regular update of knowledge in dental traumatology is required.


Assuntos
Traumatismos Dentários/etiologia , Fatores Etários , Processo Alveolar/lesões , Saúde Global , Humanos , Fatores de Risco , Avulsão Dentária/etiologia , Avulsão Dentária/terapia , Fraturas dos Dentes/etiologia , Fraturas dos Dentes/terapia , Traumatismos Dentários/terapia , Resultado do Tratamento
8.
Implant Dent ; 23(4): 426-33, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24776940

RESUMO

OBJECTIVES: To evaluate the effectiveness of 4 procedures to disinfect implant surfaces intentionally inoculated with bacteria and afterward to evaluate osteoblast viability to the disinfected implant surfaces. MATERIALS AND METHODS: Eighty-eight commercially pure Osseotite and Nanotite titanium implant discs were inoculated with Porphyromonas gingivalis. The implant surfaces were disinfected with EDTA, tetracycline, citric acid, or neodymium-doped yttrium aluminum garnet (Nd:YAG) laser. The implant discs were then placed in cultures of osteoblast cells. RESULTS: Osseotite implant discs were easier to disinfect compared with the Nanotite implant discs. Citric acid and tetracycline were the most effective solutions for the disinfection of P. gingivalis from the Osseotite implant discs. CONCLUSION: The Nanotite implant discs were the most difficult to disinfect, likely because of their chemical and physical properties. Citric acid and tetracycline were most effective for disinfecting the Osseotite implant discs, and further clinical research is needed to verify these effects in vivo. The Nd:YAG laser was the weakest disinfection method, and it is not recommended for disinfecting implant surfaces until its effectiveness is improved.


Assuntos
Implantes Dentários , Desinfecção , Osteoblastos/citologia , Divisão Celular , Linhagem Celular , Humanos , Nanotecnologia , Osteoblastos/microbiologia , Porphyromonas gingivalis/efeitos dos fármacos , Porphyromonas gingivalis/crescimento & desenvolvimento , Propriedades de Superfície
9.
Quintessence Int ; 43(5): 387-95, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22536590

RESUMO

OBJECTIVE: Laser-assisted gingivectomies are performed in proximity to teeth, existing restorations, and implants. In case of accidental exposures, a detrimental surface defect may cause failure. Surface interactions should be evaluated for safety margin determination of certain laser-material combinations. The purpose of this in vitro study was to assess the microscopic and visible effects of CO2, Nd:YAG, and 810-nm diode laser irradiations on various dental materials and tooth tissue. METHOD AND MATERIALS: Study samples were fabricated (10 x 7.5 mm irradiation surface area, 1 mm thickness) from eight material groups (amalgam, base metal, gold, palladium-silver, composite, ceramic, titanium, and extracted tooth slices). Laser irradiations were performed with CO2, Nd:YAG, and 810-nm diode lasers using the manufacturer's recommended settings for gingivectomy at a 45-degree angle for 30 seconds. Irradiated surfaces were evaluated under SEM at 200x and 1,000x magnifications. Standardized photographs were obtained using a camera mount system (10x high-definition macro lens). The SEM images and photographs were correlated to determine surface interactions. RESULTS: Nd:YAG detrimentally affected all metallic materials and tooth structures. CO2 altered amalgam, gold, and palladium-silver slightly, whereas composite, ceramic, and tooth surfaces were detrimentally altered. The 810-nm diode altered amalgam, gold, titanium, palladium-silver, and composite but only gold and palladium-silver surfaces were barely traceable. CONCLUSION: Within the limitations of this in vitro study, surface effects were all instant; therefore, even a short accidental exposure may be destructive in some laser-material combinations. During gingivectomies, CO2 near tooth-colored restorations and Nd:YAG near metallic restorations and implants should be used carefully. The 810-nm diode was found to be safer due to its reversible alterations in only some materials. Further in vivo studies are necessary to clinically apply the outcomes of this study.


Assuntos
Materiais Dentários/química , Restauração Dentária Permanente , Gengivectomia/instrumentação , Terapia a Laser/instrumentação , Lasers , Resinas Compostas/química , Ligas Dentárias/química , Amálgama Dentário/química , Porcelana Dentária/química , Ligas de Ouro/química , Humanos , Lasers de Gás/uso terapêutico , Lasers Semicondutores/uso terapêutico , Lasers de Estado Sólido/uso terapêutico , Teste de Materiais , Microscopia Eletrônica de Varredura , Paládio/química , Fotografação , Segurança , Prata/química , Propriedades de Superfície , Titânio/química , Dente/patologia
10.
Stomatologija ; 12(2): 42-50, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20679755

RESUMO

OBJECTIVE: The purpose of this study was to gather information about the various aspects, technical and biological, of endodontic treatment as performed by Lithuanian general dental practitioners and to compare their choices with established endodontic treatment standards of undergraduate education. MATERIALS AND METHODS: Questionnaires were sent to all 2,850 Lithuanian dental practitioners. The structured questionnaire included inquiries about gender, duration of professional activity, working environment, details about instruments and materials. RESULTS: From total 1532 (53.8%) questionnaires were returned. Only responses from general dental practitioners (1431) were included. Of the respondents 66% never used a rubber dam. Most practitioners relied on conventional stainless steel instruments. The NiTi hand files were often and routinely used by 32.2% of the respondents. Sodium hypochlorite was the most popular choice as a root canal irrigant. Calcium hydroxide paste was used as an inter-appointment medicament. Cold-lateral condensation root filling method was used by 72.8% of the respondents while 15.6% used a paste for the root filling. CONCLUSIONS: The results of this study indicate that the recently graduated dental practitioners were following the recommended standard of endodontic treatment better than those with a longer time from the graduation. It is important to improve the quality of existing courses of continuous education in endodontology in order to ensure the necessary competency in clinical practice. The low use of a rubber dam and low adoption of new technologies in Lithuania is not acceptable and needs to be changed.


Assuntos
Odontologia Geral , Padrões de Prática Odontológica , Tratamento do Canal Radicular/métodos , Adulto , Idoso , Hidróxido de Cálcio/uso terapêutico , Odontologia Comunitária , Ligas Dentárias/química , Ácido Edético/uso terapêutico , Endodontia/educação , Desenho de Equipamento , Feminino , Odontologia Geral/educação , Humanos , Lituânia , Masculino , Pessoa de Meia-Idade , Níquel/química , Prática Privada , Prática Profissional , Materiais Restauradores do Canal Radicular/uso terapêutico , Irrigantes do Canal Radicular/uso terapêutico , Obturação do Canal Radicular/métodos , Tratamento do Canal Radicular/instrumentação , Tratamento do Canal Radicular/normas , Diques de Borracha/estatística & dados numéricos , Hipoclorito de Sódio/uso terapêutico , Aço Inoxidável/química , Inquéritos e Questionários , Titânio/química , Adulto Jovem
11.
Medicina (Kaunas) ; 46(9): 611-5, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21252595

RESUMO

OBJECTIVE: To analyze the need for referral to a specialist and to identify the reasons of referrals among Lithuanian general dental practitioners. MATERIAL AND METHODS: Questionnaires were sent to all 2879 Lithuanian dental practitioners registered on the Lithuanian Dental Chamber license registry. The questionnaire was made with multiple-choice answers. Respondents were asked to choose only one category of answer that best fitted their clinical attitude. Questions included in the questionnaire concerned general and specific information regarding the need and main reasons for endodontic referral. RESULTS: Of the 2879 questionnaires mailed, 1532 questionnaires containing useful information were returned. The response rate was 53.2%. Of the 1532 respondents, 1431 were general dental practitioners. Majority (72.1%) of the respondents performed complicated root canal treatment by themselves. Almost half (49.6%) of them would like to refer patients to an endodontist. Two of the reasons, which restricted their decision, were the shortage of endodontists and high cost of the procedures in the specialized clinics. Approximately 19% of the respondents referred patients to an endodontist. The main reasons for referral were fractured instruments (86.6%), dental trauma (83.6%), difficulties in diagnostics (79%) followed by persistent symptoms (78.1%). CONCLUSION: The findings of the present study suggest that the need for referral of patients to an endodontist among Lithuanian dental practitioners exists. The main reasons for referrals were complications of endodontic treatment, traumatic injuries, difficulties in diagnostic procedures, and persistent symptoms.


Assuntos
Odontologia , Endodontia , Encaminhamento e Consulta , Endodontia/economia , Humanos , Lituânia , Tratamento do Canal Radicular , Inquéritos e Questionários , Recursos Humanos
12.
Stomatologija ; 11(3): 77-82, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19996673

RESUMO

OBJECTIVE: To gather information about the radiographic facilities and techniques used by Lithuanian general dentists. MATERIALS AND METHODS: Questionnaires were sent to all 2879 Lithuanian dental practitioners registered on the Lithuanian Dental Chamber licence registry data list. The questionnaire was made with multiple-choice answers. Respondents were invited to choose the only one category of answer that best fitted their clinical attitude. Questions included in the present survey concerned general and specific information regarding peculiarities of radiographic imaging. Only answers of respondents who are licensed as general dentists were included in this study. RESULTS: From the 2850 questionnaires mailed 1532 were returned. The response rate was 53.8%. Of the total responses 1431 questionnaires were received from licensed general dentists. Of total 956 dentists practiced in urban and 576 dentists in rural areas. 61.6% of respondents had access to an intra-oral radiographic unit in their practice and 91.5% of them used dental radiography always or often as the diagnostic tool. To support the film packet in the patient's mouth alternatively film holder or patient's finger was used by 48% of respondents, while film holder was used only by 19.3% of dentists. CONCLUSION: Recently graduated dental practitioners more common used diagnostic radiography in endodontic pathology than dentists with a longer time from graduation. Film holder was not a popular device among general dental practitioners to perform periapical radioraphs. It is important to improve the existing dental curriculum to ensure the necessary competency when using dental radiography and film holders routinely in clinical practice.


Assuntos
Doenças da Polpa Dentária/diagnóstico por imagem , Odontologia Geral/estatística & dados numéricos , Doenças Periapicais/diagnóstico por imagem , Padrões de Prática Odontológica/estatística & dados numéricos , Radiografia Dentária/estatística & dados numéricos , Adulto , Idoso , Serviços de Saúde Comunitária/estatística & dados numéricos , Feminino , Humanos , Lituânia , Masculino , Pessoa de Meia-Idade , Prática Privada/estatística & dados numéricos , Radiografia Dentária/instrumentação , Inquéritos e Questionários , Adulto Jovem
13.
Stomatologija ; 11(1): 11-4, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19423965

RESUMO

Research data regarding attitudes of general dental practitioners towards endodontic therapy is rare. The present review summarizes existing literature and analyzes human factors that could potentially influence the outcome of endodontic treatment in general dental practice. Root canal treatment usually fails when treatment falls short of acceptable standards. The results of questionnaire surveys from several countries indicate that differences between daily general practice and academic teaching exist. The results of studies indicated that majority of general practitioners disregard the most basic principles of endodontic treatment. The most striking finding is the generally negative attitude amongst general dental practitioners towards performing endodontic treatment and adoption of new technologies in a daily endodontic practice. The results confirm that root canal treatment is technically demanding and in general practice is carried out under less than optimal conditions. This review shows the importance of continuous dental education for practitioners in order to update their knowledge.


Assuntos
Atitude do Pessoal de Saúde , Odontologia Geral , Tratamento do Canal Radicular/psicologia , Instrumentos Odontológicos , Endodontia/educação , Humanos , Materiais Restauradores do Canal Radicular , Irrigantes do Canal Radicular , Diques de Borracha/estatística & dados numéricos , Inquéritos e Questionários , Ápice Dentário/anatomia & histologia
14.
Stomatologija ; 11(1): 21-5, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19423967

RESUMO

OBJECTIVE: The aim of this study was to determine and compare the microbial leakage of roots filled with EndoREZ sealer/EndoREZ Points and AH Plus sealer/ conventional gutta-percha points. MATERIALS AND METHODS: 60 single-rooted teeth were prepared using step-back technique. The smear layer was removed with 18% EDTA. Teeth were divided into two experimental groups (n=25 each group) and two controls (n=5 each group). In AH Plus group root canals were obturated with AH Plus sealer/gutta-percha and in EndoREZ group with EndoREZ sealer/EndoREZ Points. Five teeth were served as negative controls and five as positive controls. All teeth were inserted into Eppendorf plastic tubes and suspended in glass bottles containing sterile Schaedler broth. The coronal chambers were filled with the mix of human saliva and broth (ratio 3:1). The medium was changed every 7 days. Microbial growth in the broth was evaluated every day up to the end of experiment. RESULTS: Leakage in the root canals of the teeth from experimental groups occurred between 4 and 75 days. The mean leakage in AH Plus group was 18.86 days, while in EndoREZ group it was 28.28. No statistically significant difference in microbial leakage between two tested filling materials was found. CONCLUSION: Both types of root fillings - EndoREZ sealer/EndoREZ Points and AH Plus sealer/gutta-percha points - showed microbial leakage.


Assuntos
Infiltração Dentária , Materiais Restauradores do Canal Radicular , Obturação do Canal Radicular , Resinas Compostas , Infiltração Dentária/prevenção & controle , Resinas Epóxi , Guta-Percha , Humanos
15.
J Prosthodont ; 17(5): 357-64, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18544138

RESUMO

PURPOSE: Plasma-sprayed hydroxyapatite (HA)-coated implants show failures along the coating-substrate interface due to poor bond strength. We analyzed HA coatings obtained by pulsed laser deposition (PLD) and compared them to commercially used plasma-sprayed coatings with respect to their bond strength to titanium alloy (Ti-6Al-4V), as well as surface roughness alterations produced by each of the two deposition methods. MATERIALS AND METHODS: Twelve titanium alloy disks were plasma-sprayed under commercial implant coating conditions, and 24 titanium alloy disks were coated using PLD. All coatings were characterized by the presence of the different calcium phosphate (CaP) phases. The plasma-sprayed coatings (n = 12) were predominantly HA, and the pulsed laser-deposited coatings were hydroxydyapatite (n = 12) and HA coating with a tetra calcium phosphate (TTCP) phase (n = 12). The surface roughness was analyzed before and after the coating processes to assess roughness changes to the surface by the coatings. The adhesive bond strengths of these coatings to the substrate titanium alloy was tested and compared. Scheffé's test was used to analyze the statistical significance of the data. RESULTS: The surface roughness alteration following PLD was a decrease of 0.2 mum, whereas following plasma spraying the decrease was 1.0 microm. Bond strengths were as follows [mean (SD) in MPa]: pulsed laser-deposited HA coatings: 68.3 (17.8); pulsed laser-deposited HA with tetra-CaP: 55.2 (21.1); plasma-sprayed HA 17.0 (2.8). The multivariate Scheffé's test revealed that HA coatings obtained by PLD had significantly increased bond strengths compared with the plasma sprayed ones (p

Assuntos
Materiais Revestidos Biocompatíveis , Implantes Dentários , Adesividade , Análise de Variância , Fosfatos de Cálcio , Cristalografia por Raios X , Ligas Dentárias , Colagem Dentária , Análise do Estresse Dentário , Durapatita , Microanálise por Sonda Eletrônica , Lasers de Excimer , Microscopia Eletrônica de Varredura , Propriedades de Superfície , Resistência à Tração , Titânio
16.
Stomatologija ; 10(1): 4-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18493159

RESUMO

A traditional concept is that apical periodontitis is the result of pathogenic effects of the microorganisms colonizing the root canal system and the response of the host defence system. The composition of the microflora of root canals differs in primary endodontic treatment and retreatment cases. Persistent disease in the periapical region after root canal treatment presents a more complex situation as it was thought earlier. Scientific evidence indicates that unsatisfactory outcome of cases in which treatment has followed the highest technical standards mainly is associated with microbial factors, comprising extraradicular and/or intraradicular infections.


Assuntos
Bactérias/classificação , Cavidade Pulpar/microbiologia , Periodontite Periapical/microbiologia , Tratamento do Canal Radicular , Humanos , Resultado do Tratamento
17.
Stomatologija ; 8(3): 70-5, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17191061

RESUMO

AIM: To compare in vitro the cleanliness of root canal walls following automated or manual instrumentation. METHODOLOGY: Thirty extracted human maxillary central incisors, maxillary and mandibular canines and premolars with single root canals were used in this study. The teeth were divided into two groups. In group 1 (20 teeth) automated canal preparation was performed using Anatomic Endodontic Technology (AET). In group 2 (10 teeth) manual instrumentation was performed with K-Flexofiles. Irrigation was performed using alternately 3.00% NaOCl and 18% EDTA, followed by rinsing with saline. The roots were split longitudinally into halves and the canals examined using a scanning electron microscope. The presence of debris and smear layer was recorded at coronal, middle and apical thirds of root canals using a four-step scoring scale. Mean scores for debris and smear layer were calculated and statistically analysed for significance (P<0.05) between and within groups, using the Mann-Whitney-Wilcoxon and Friedman nonparametric tests. RESULTS: At coronal and middle thirds the root canals prepared with manual instrumentation had significantly less surface debris on the canal walls compared with canals prepared with AET (p<0.05). At apical third root canals prepared with manual instrumentation had significantly more debris compared with AET group. The amount of smear layer was greater in the apical than in the coronal and middle thirds of the root and significantly less amount was in the AET group (P<0.05). CONCLUSIONS: Complete cleanliness was not achieved by any of the techniques and instruments investigated. It may be inferred that the choice between AET and hand instrumentation should be based on factors other than the amount of root canal debridement, which does not vary high significantly according to the instruments used.


Assuntos
Cavidade Pulpar/ultraestrutura , Dentina/ultraestrutura , Preparo de Canal Radicular/instrumentação , Camada de Esfregaço , Quelantes/uso terapêutico , Ácido Edético/uso terapêutico , Desenho de Equipamento , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Irrigantes do Canal Radicular/uso terapêutico , Cloreto de Sódio , Hipoclorito de Sódio/uso terapêutico , Ápice Dentário/ultraestrutura
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