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Made available in DSpace on 2020-12-12T01:55:54Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-01-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Statement of problem: Changes in physicochemical properties because of implant material aging and natural deterioration in the oral environment can facilitate microbial colonization and disturb the soft-tissue seal between the implant surfaces. Purpose: The purpose of this in vitro study was to investigate the effect of aging time on the physicochemical profile of titanium (Ti) and zirconia (ZrO2) implant materials. Further microbiology and cell analyses were used to provide insights into the physicochemical implications of biological behavior. Material and methods: Disk-shaped specimens of Ti and ZrO2 were submitted to roughness, morphology, and surface free energy (SFE) analyses before nonaging (NA) and after the aging process (A). To simulate natural aging, disks were subjected to low-temperature degradation (LTD) by using an autoclave at 134 ºC and 0.2 MPa pressure for 20 hours. The biological activities of the Ti and ZrO2 surfaces were determined by analyzing Candida albicans (C. albicans) biofilms and human gingival fibroblast (HGF) cell proliferation. For the microbiology assays, a variance analysis method (ANOVA) was used with the Tukey post hoc test. For the evaluation of cellular proliferation, the Kruskal-Wallis test followed by Dunn multiple comparisons were used. Results: Ti nonaging (TNA) and ZrO2 nonaging (ZNA) disks displayed hydrophilic and lipophilic properties, and this effect was sustained after the aging process. Low-temperature degradation resulted in a modest change in intermolecular interaction, with 1.06-fold for TA and 1.10-fold for ZA. No difference in biofilm formation was observed between NA and A disks of the same material. After 48 hours, the viability of the attached HGF cells was very similar to that in the NA and A groups, regardless of the tested material. Conclusion: The changes in the physicochemical properties of Ti and ZrO2 induced by the aging process do not interfere with C. albicans biofilm formation and HGF cell attachment, even after long-term exposure. Masters graduate Department of Dental Materials and Prosthodontics School of Dentistry at Araraquara São Paulo State University (UNESP) Postdoctoral Research Fellow Department of Dental Materials and Prosthodontics School of Dentistry at Araraquara São Paulo State University (UNESP) Technical Assistant Department of Dental Materials and Prosthodontics School of Dentistry at Araraquara São Paulo State University (UNESP) Assistant Professor Department of Dentistry Federal University of Santa Catarina (UFSC) Associate Professor Department of Dental Materials and Prosthodontics School of Dentistry at Araraquara São Paulo State University (UNESP) Masters graduate Department of Dental Materials and Prosthodontics School of Dentistry at Araraquara São Paulo State University (UNESP) Postdoctoral Research Fellow Department of Dental Materials and Prosthodontics School of Dentistry at Araraquara São Paulo State University (UNESP) Technical Assistant Department of Dental Materials and Prosthodontics School of Dentistry at Araraquara São Paulo State University (UNESP) Associate Professor Department of Dental Materials and Prosthodontics School of Dentistry at Araraquara São Paulo State University (UNESP)

Made available in DSpace on 2018-12-11T17:10:48Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-10-01 Statement of problem Peri-implantitis is considered the most important biological complication responsible for late implant failure. The physical chemical properties intrinsic to each material can affect the first step to biofilm development and is an important precursor to the adaptive behavior of pathogenic bacteria species. Purpose The purpose of this in vitro study was to evaluate the effect of 2 commercially available implant abutment materials on the adhesion phase and biofilm formation. Material and methods Disks (8 mm in diameter, 2 mm thick) of machined pure titanium (Ti) and yttrium-stabilized zirconia (ZrO2) materials were used to mimic implant abutments. The physical chemical surface properties were investigated using different approaches. Initial adherent bacteria and biofilm formation were evaluated after 16 and 48 hours by incubating the disks in a rich medium containing representative saliva-derived oral microbial community. Unpaired t test, 2 tailed, was used to compare the groups. Results Ti presented lower hydrophobicity and surface free energy values than the ZrO2, and 6.1-fold fewer bacteria adhered to the Ti. After 48 hours, detailed quantitative analysis showed that biofilm biomass and biofilm density were lower on the Ti disks than on ZrO2. The quantity of phylotypes on the Ti and ZrO2 surfaces was relatively similar during the attachment and early biofilm formation periods. Conclusions Although no difference in the bacteria profile was observed between both materials independent of the time point, the highest level of colonization was on ZrO2. Postdoctoral Research Fellow Department of Dental Materials and Prosthodontics School of Dentistry at Araraquara São Paulo State University (UNESP) Araraquara Brazil; and Research Fellow School of Dentistry University of California Department of Dental Materials and Prosthodontics School of Dentistry at Araraquara São Paulo State University (UNESP) Department of Physical Chemistry Institute of Chemistry São Paulo State University (UNESP) School of Dentistry University of California Postdoctoral Research Fellow Department of Dental Materials and Prosthodontics School of Dentistry at Araraquara São Paulo State University (UNESP) Araraquara Brazil; and Research Fellow School of Dentistry University of California Department of Dental Materials and Prosthodontics School of Dentistry at Araraquara São Paulo State University (UNESP) Department of Physical Chemistry Institute of Chemistry São Paulo State University (UNESP)

For the long-term success of implants, it is necessary to achieve a direct contact between the implant and the subjacent bone. To avoid bacterial penetration that could adversely affect the initial wound healing as well as the long-term behavior of the implants, an early tissue barrier must form that is able to protect the biological peri-implant structures. Given the need of an effective tissue early barrier around dental implants, the present study evaluated, in vitro, the influence of physical and chemical characteristics of two implant abutment surfaces on gingival epithelial cells (OBA-9) adhesion. To this end, titanium (Ti) and zirconia (ZrO2 ) disk-shaped specimens were used mimicking the abutment components surfaces, while bovine enamel (BE) and glass cover slips (GCS) disks served as positive and negative controls, respectively. Roughness and surface free energy (SFE) of all materials were evaluated previously to cellular adhesion step. In sequence, the effect of each material on cells morphology and viability was analyzed after 1 and 24 hr. The results showed that roughness and SFE had no effect on the cell viability data or on their interaction (p = .559), independent of a post-contact analysis of 1 or 24 hr. However, cells attachment and spreading increased after 24 hr on Ti and ZrO2 than BE, corresponding to the highest SFE values. SFE appears to be an important property interfering on the quality of the soft tissue surrounding dental implants. These data can be considered a trigger point for developing new material surfaces.

Orthodontic extrusion with multidisciplinary treatment can provide predictable outcomes in selected situations, reducing the costs and the adaptation times of gingival tissues after implant integration. Forced orthodontic extrusion is strongly related to interactions of teeth with their supportive periodontal tissues. This article reports a case of orthodontic extrusion of the maxillary incisors for later implant rehabilitation in a patient with periodontal disease. Slow forces were applied for 14 months. After this time, the teeth were extracted, and the implants were placed on the same day. Also in the same session, the provisional crown was fabricated for restoration of the anterior maxillary interdental papillae loss and for gingival contouring. Clinical and radiographic examinations at the 6-year follow-up showed successful tooth replacement and an improved esthetic appearance achieved by this multidisciplinary treatment. The decision to perform orthodontic extrusion for implant placement in adult patients should be multidisciplinary.

Made available in DSpace on 2015-08-06T16:13:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2014. Added 1 bitstream(s) on 2015-08-06T16:43:42Z : No. of bitstreams: 1 ISSN2090-6447-2014-2014-01-08.pdf: 6435515 bytes, checksum: 91ca6a70fe3844c8b5e20fec571988cb (MD5) The aim of this paper is to present a complex rehabilitation, of fractured tooth, with implants in anterior region considering the orthodontics extrusion to clinical success. At 7 years old, the patient fractured the maxillary left central incisor and the dentist did a crown with the fragment. Twenty years later, the patient was referred to a dental clinic for orthodontic treatment, with the chief complaint related to an accentuated deep bite, and a professional started an orthodontic treatment. After sixteen months of orthodontic treatment, tooth 21 fractured. The treatment plan included an orthodontic extrusion of tooth 21 and implant placement. This case has been followed up and the clinical and radiographic examinations show excellence esthetic results and satisfaction of patient. The forced extrusion can be a viable treatment option in the management of crown root fracture of an anterior tooth to gain bone in a vertical direction. This case emphasizes that to achieve the esthetic result a multidisciplinary approach is necessary. Universidade Estadual Paulista Júlio de Mesquita Filho, Departamento de Materiais Odontológicos e Prótese, Faculdade de Odontologia de Araraquara, Araraquara, Rua Humaitá, n. 1680, Centro, CEP 14801-903, SP, Brasil University of Sagrado Coração, Department of Orthodontics, 10-50 Irma Arminda Street, 17011-160 Bauru, SP, Brazil Campinas State University, Department of Physiological Sciences, Piracicaba Dental School, 901 Limeira Avenue, 13414-903 Piracicaba, SP, Brazil Universidade Estadual Paulista Júlio de Mesquita Filho, Departamento de Materiais Odontológicos e Prótese, Faculdade de Odontologia de Araraquara, Araraquara, Rua Humaitá, n. 1680, Centro, CEP 14801-903, SP, Brasil Universidade Estadual Paulista Júlio de Mesquita Filho, Department of Diagnostic and Surgery, Araraquara School of Dentistry, 1680 Humaita Street, 14801-903 Araraquara, SP, Brazil Universidade Estadual Paulista Júlio de Mesquita Filho, Department of Social Dentistry, Araraquara School of Dentistry, 1680 Humaita Street, 14801-903 Araraquara, SP, Brazil