Extrusão dos implantes em portadores de cavidade anoftálmica

Purpose: To evaluate the characteristics of patients with anophthalmic cavity who developed sphere extrusion. Methods: A retrospective observational study was done evaluating 37 patients with anophthalmic cavity and sphere extrusion at the Faculdade de Medicina de Botucatu-UNESP. Results: Extrusion was observed in enucleated and eviscerated cavities. The majority of the patients had the eye removed because of phthisis bulbi or trauma and the extrusion happened 1 or 2 years after the surgery. Extrusion was preceded by conjunctival dehiscence and exposure of the sphere and occurred with all used implants. Conclusion: Complications after orbital implant placement are a possibility. Dehiscence and sphere extrusion may happen and another surgery would be necessary. The patient and the ophthalmologist have to be prepared for this.

Bone spreading technique a case report

Bone spreading technique (BST) is a horizontal augmentation with minimal trauma for simultaneous implant placement and an alternative to Summer's osteotome technique both for its clinical use and for the armamentarium. The foremost advantage of the crest dilation technique is a substantially less invasive method; the buccal wall expands after the medullary bone is compressed against the cortical bone. The lateral dilation and compaction of medullary bone improved primary stability. The vital difference is that the BST used in this case report avoided discomfort of the patient, thus eliminating the need for malleting.

Rehabilitation with zygomatic implants: a treatment option for the atrophic edentulous maxilla--9-year follow-up.

This article reports the 9-year clinical outcome of the two-stage surgical rehabilitation of a severely atrophic edentulous maxilla with a metal-resin fixed denture supported by implants anchored in the zygomatic bone and the maxilla. After clinical and radiographic examination, zygomatic implants were inserted bilaterally and four standard implants were placed in the anterior region of the maxilla. Six months later, the implants were loaded with a provisional acrylic resin denture, and the definitive implant-supported metal-resin fixed denture was provided 1 year after implant placement. After 9 years of follow-up, no painful symptoms, peri-implant inflammation or infection, implant instability, or bone resorption was observed. In the present case, the rehabilitation of severe maxillary atrophy using the zygomatic bone as a site for implant anchorage provided good long-term functional and esthetic results. Therefore, with proper case selection, correct indication, and knowledge of the surgical technique, the use of zygomatic implants associated with standard implants offers advantages in the rehabilitation of severely resorbed maxillae, especially in areas with inadequate bone quality and volume, without needing an additional bone grafting surgery, thereby shortening or avoiding hospital stay and reducing surgical morbidity.

Osseointegration assessment of chairside argon-based nonthermal plasma-treated Ca-P coated dental implants

This study investigated the effect of an Argon-based nonthermal plasma (NTP) surface treatment-operated chairside at atmospheric pressure conditions applied immediately prior to dental implant placement in a canine model. Surfaces investigated comprised: Calcium-Phosphate (CaP) and CaP + NTP (CaP-Plasma). Surface energy was characterized by the Owens-Wendt-Rabel-Kaelble method and chemistry by X-ray photoelectron spectroscopy (XPS). Six adult beagles dogs received 2 plateau-root form implants (n = 1 each surface) in each radii, providing implants that remained 1 and 3 weeks in vivo. Histometric parameters assessed were bone-to-implant contact (BIC) and bone area fraction occupancy (BAFO). Statistical analysis was performed by Kruskall-Wallis (95% level of significance) and Dunn's post-hoc test. The XPS analysis showed peaks of Ca, C, O, and P for the CaP and CaP-Plasma surfaces. Both surfaces presented carbon primarily as hydro-carbon (CAC, CAH) with lower levels of oxidized carbon forms. The CaP surface presented atomic percent values of 38, 42, 11, and 7 for C, O, Ca, and P, respectively, and the CaPPlasma presented increases in O, Ca, and P atomic percent levels at 53, 12, and 13, respectively, in addition to a decrease in C content at 18 atomic percent. At 1 week no difference was found in histometric parameters between groups. At 3 weeks significantly higher BIC and BAFO were observed for CaPPlasma treated surfaces. Surface elemental chemistry was modified by the Ar-based NTP. Ar-based NTP improved bone formation around plateau-root form implants at 3 weeks compared with CaP treatment alone. © 2012 Wiley Periodicals, Inc.

Autogenous bone combined with anorganic bovine bone for maxillary sinus augmentation: Analysis of the osteogenic potential of cells derived from the donor and the grafted sites

Objectives: This study aimed to comparatively evaluate the in vitro osteogenic potential of cells obtained from the mandibular ramus (MR, autogenous bone donor site) and from the maxillary sinus (MS) bone grafted with a mixture of anorganic bovine bone (ABB) and MR prior to titanium implant placement (MS, grafted implant site). Material and methods: Cells were obtained from three patients subjected to MS floor augmentation with a 1: 1 mixture of ABB (GenOx Inorg®) and MR. At the time of the sinus lift procedure and after 8 months, prior to implant placement, bone fragments were taken from MR and MS, respectively, and subjected to trypsin-collagenase digestion for primary cell culturing. Subcultured cells were grown under osteogenic condition for up to 21 days and assayed for proliferation/viability, osteoblast marker mRNA levels, alkaline phosphatase (ALP) activity and calcium content/Alizarin red staining. ALP activity was also determined in primary explant cultures exposed to GenOx Inorg® (1: 1 with MR) for 7 days. Data were compared using either the Mann-Whitney U-test or the Kruskal-Wallis test. Results: MS cultures exhibited a significantly lower osteogenic potential compared with MR cultures, with a progressive increase in cell proliferation together with a decrease in osteoblast markers, reduced ALP activity and calcium content. Exposure of MR-derived primary cultures to GenOx Inorg® inhibited ALP activity. Conclusion: These results suggest that the use of GenOx Inorg® in combination with MR fragments for MS floor augmentation inhibits the osteoblast cell differentiation at the implant site in the long term. © 2013 John Wiley & Sons A/S.

Fate of autologous and fresh-frozen allogeneic block bone grafts used for ridge augmentation. A CBCT-based analysis

Objectives: To evaluate dimensional changes in autologous (AT) and fresh-frozen allogeneic (AL) block bone grafts 6 months after alveolar ridge augmentation. Material and methods: Twenty-six partially or totally edentulous patients treated either with fresh-frozen AL bone or AT bone onlay block grafts prior to implant placement (13 patients in each group), were included in this analysis. Patients received CBCT (i-CAT Classic) examinations prior to surgery and 14 days and 6 months after grafting. Differences in alveolar ridge area among the various observation times were evaluated by planimetric measurements on two-dimensional CBCT images of the grafted regions. Nineteen grafted blocks from each group were evaluated. Results: Significant increase in alveolar ridge dimensions, allowing implant placement, was obtained with both types of grafts 6 months after grafting; no significant differences in alveolar ridge area were observed between the groups at the various observation times. However, graft resorption in the AL group was significantly larger compared to that in the AT group at 6 months. Conclusions: Larger bone graft resorption was seen in patients treated with fresh-frozen AL bone than in those treated with AT bone 6 months following alveolar ridge augmentation. © 2011 John Wiley & Sons A/S.

Histomorphometrical and molecular evaluation of endosseous dental implants sites in humans: Correlation with clinical and radiographic aspects

Objective: To evaluate the correlations between clinical-radiographical aspects and histomorphometric-molecular parameters of endosseous dental implant sites in humans. Material and methods: The study sample consisted of bone implant sites from the jawbones of 32 volunteers, which were classified according to two different systems: (1) based only on periapical and panoramic images (PP); (2) as proposed by Lekholm & Zarb (L&Z). Bone biopsies were removed using trephine during the first drilling for implant placement. Samples were stained with haematoxylin-eosin (HE), and histomorphometric analysis was performed to obtain the following parameters: trabecular thickness (Tb.Th), trabecular number, bone volume density (BV/TV), bone specific surface (BS/BV), bone surface density and trabecular separation (Tb.Sp). In addition, immunohistochemistry analysis was performed on bone tissue samples for the proteins, Receptor activator of nuclear factor kappa-B (RANK), RANK ligand (RANKL), osteoprotegerin (OPG) and Osteocalcin (OC). Also, the determination of the relative levels of gene expression was performed using Reverse transcription-real-time Polymerase Chain Reaction (RT-PCR). Results: PP and L&Z classification systems revealed a moderate correlation with BV/TV, BS/BV, Tb.Th and Tb.Sp. L&Z's system identified differences among bone types when BV/TV, BS/BV, Tb.Th and Tb.Sp were compared. A weak correlation between PP/L&Z classifications and the expression of bone metabolism regulators (RANK, RANKL, OPG e OC) was found. The analysis of mRNA expression showed no difference between the bone types evaluated. Conclusions: Our results suggest that PP and L&Z subjective bone-type classification systems are related to histomorphometric aspects. These data may contribute to the validation of these classifications. Bone remodelling regulatory molecules do not seem to influence morphological aspects of the jawbone © 2011 John Wiley & Sons A/S.

Immunological aspects of fresh-frozen allogeneic bone grafting for lateral ridge augmentation

Objectives: To present some immunological aspects of fresh-frozen allogeneic bone grafting for lateral bone augmentation, based on the quantitative evaluation of IL-10, IL-1β, IFN- γ and TNF- α in patients sera. Material and methods: Thirty-three partially or totally edentulous patients received fresh-frozen allogeneic bone (AL - 20 patients) or autologous bone onlay block grafts (AT - 13 patients) prior to oral implant placement. Blood samples were collected from each patient at various time-points during a 6 month-period (baseline, 14, 30, 90 and 180 days postoperatively). Quantitative evaluation of IL-10, IL-1β, IFN- γ and TNF- α was performed by enzyme linked immunosorbent assay (ELISA). Results: For all evaluated markers and at all evaluated periods, inter-group comparisons showed no statistically significant differences between the groups, while the observed values were within normal levels. For AL-treated patients, intra-group evaluation showed statistically significant increase of TNF-α from baseline to 90 (P < 0.001) and 180 (P < 0.01) days, and from 14 to 90 (P < 0.01) and 180 (P < 0.05) days. IFN- γ showed intercalated results, with a decrease from baseline to 14 days (P < 0.05), and increase from 14 to 90 days (P < 0.001) and 180 (P < 0.05) days. No differences between the periods of evaluation were found for the AT group. Conclusions: AL grafting for lateral bone augmentation, similar to AT grafting, does not seem to challenge the immune system significantly. © 2012 John Wiley & Sons A/S.

Six-year follow-up of maxillary anterior rehabilitation with forced orthodontic extrusion: Achieving esthetic excellence with a multidisciplinary approach

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. Copyright © 2013 by the American Association of Orthodontists.

Avaliação da remodelação óssea após a interrupção do tratamento com bifosfonato por um período prolongado e seu efeito sobre a osseointegração

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Avaliação do padrão de reparação óssea ao redor de implantes submersos: estudo experimental em cães

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação da influência da velocidade de perfuração na reabsorção óssea ao redor de implantes osseointegrados instalados por meio de cirurgia guiada sem retalho: estudo clínico, radiográfico e histológico

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Influência do tipo de conexão protética, do platform-switching e do designe do implante no ambiente biomecânico de implantes imediatos com carga imediata

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Avaliação da influência da osteoporose induzida em ratas, e seu tratamento com alendronato e estrógeno, sobre o tecido ósseo ao redor de implantes

Pós-graduação em Odontologia - FOAR

Avaliação do comportamento de quatro biomateriais associados a enxertos ósseos autógenos nos procedimentos cirúrgicos de elevação de seio maxilar. Estudo histomorfométrico em humanos

Pós-graduação em Odontologia - FOAR