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991.
992.
da Silva LC de Almeida Freitas R de Andrade MP Piva MR Martins-Filho PR de Santana Santos T 《The Journal of craniofacial surgery》2012,23(3):e214-e218
To prevent rejection of kidney transplants, patients must be kept in immunosuppressive therapy for a long time, which includes the use of drugs such as cyclosporine, azathioprine, cyclophosphamide, and prednisone. The action of these drugs reduces the general immune response of transplant patients and thus increases their susceptibility to infections. Moreover, these drugs increase the potential of developing lesions. Therefore, oral hygiene in kidney transplant recipients contributes to maintenance of the transplanted organ and its function. Thus, an investigation of oral lesions could be counted as a notable work. The aim of this study was to investigate oral lesions in a group of 21 kidney transplant patients under immunosuppressive therapy attended during a 1-year period in the Nephrology Department of the Federal University of Sergipe, Brazil. Data related to sex, age, etiology of renal disease, types of renal transplant, time elapsed after transplantation, immunosuppressive treatment, use of concomitant agents, and presence of oral lesions were obtained. All patients received a kidney transplant from a living donor, and the mean posttransplantation follow-up time was 31.6 months; 71.5% used triple immunosuppressive therapy with cyclosporine A, azathioprine, and prednisone. Ten patients were also treated with calcium-channel blockers. Of the 21 transplant patients, 17 (81%) presented oral lesions. Gingival overgrowth was the most common alteration, followed by candidiasis and superficial ulcers. One case of spindle cell carcinoma of the lower lip was observed. Oral cavity can harbor a variety of manifestations related to renal transplantation under immunosuppressive therapy. 相似文献
993.
Carlos C. Goizueta AdameMario F. Muñoz-Guerra 《Journal of cranio-maxillo-facial surgery》2012,40(1):86-91
Aim
Several procedures have been described to reposition and secure the disc during arthroscopic surgery of the temporomandibular joint. The usefulness of these procedures remains controversial since simple lysis and lavage shows a high percentage of clinical success and it is difficult to obtain radiological imaging of the surgically acquired new disc position. This report describes a new arthroscopic discopexy method, and the clinical as well as radiological results obtained with this new technique.Methods
Sixteen patients with a clinical and radiological diagnosis of Temporomandibular Joint (TMJ) dysfunction (TMD) were treated using our discopexy method. Each patient was evaluated with a visual analogue scale (VAS) for pain, radiological and functional parameters. The evaluation also included a clinical examination. Each patient was recorded at baseline before surgery and at a one-year follow-up. Statistical analysis was performed to evaluate the differences in VAS, maximum opening and lateral movements before and after treatment and were considered statistically significant when p < 0.05.Results
Patient evaluation showed an improvement in the clinical parameters. There were statistically significant reductions in the amount of pain according to the VAS (p < 0.01). Maximal interincisal opening (MIO) and contralateral translation movement (CTM) (p < 0.05) were substantially improved one-year after operation. In the post-surgical MRI study at the one-year follow-up, a significant improvement in the disc position was observed in 13 out of the 16 joints operated on.Conclusion
This method of arthroscopic disc repositioning is an effective surgical method for treating symptomatic patients with a diagnosis of TMJ disc displacement. Because of the minimally invasive character of the procedure, it should be considered in the surgical treatment of TMJ dysfunction. 相似文献994.
da Silva LC Oliveira AC dos Santos JA Santos Tde S 《Journal of cranio-maxillo-facial surgery》2012,40(7):604-607
ObjectiveThe aim of this study was to analyze the criteria employed for the requesting of preoperative tests among maxillofacial surgeons.Materials and methodsThirty maxillofacial surgeons working in Aracaju (Brazil) received a questionnaire to fill out. The study inquired about the practice of requesting preoperative tests for healthy patients scheduled to undergo elective surgery.ResultsMost of the surgeons interviewed requested tests that are not recommended for the case in question. The highest frequency of requests was a complete blood count, coagulation test, blood glucose test and chest radiograph.ConclusionThe absence of strict rules for the requesting of preoperative tests causes uncertainty and a lack of criteria regarding pre-surgical conduct. It was not possible to clearly define the criteria used by surgeons for requesting such tests, as the clinical characteristics of the hypothetical case presented suggest a smaller number of tests. 相似文献
995.
996.
997.
Gurgel-Juarez NC de Almeida EO Rocha EP Freitas AC Anchieta RB de Vargas LC Kina S Fran?a FM 《Journal of prosthodontics》2012,21(3):160-166
Purpose: This study aimed to evaluate stress distribution on peri‐implant bone simulating the influence of platform switching in external and internal hexagon implants using three‐dimensional finite element analysis. Materials and Methods: Four mathematical models of a central incisor supported by an implant were created: External Regular model (ER) with 5.0 mm × 11.5 mm external hexagon implant and 5.0 mm abutment (0% abutment shifting), Internal Regular model (IR) with 4.5 mm × 11.5 mm internal hexagon implant and 4.5 mm abutment (0% abutment shifting), External Switching model (ES) with 5.0 mm × 11.5 mm external hexagon implant and 4.1 mm abutment (18% abutment shifting), and Internal Switching model (IS) with 4.5 mm × 11.5 mm internal hexagon implant and 3.8 mm abutment (15% abutment shifting). The models were created by SolidWorks software. The numerical analysis was performed using ANSYS Workbench. Oblique forces (100 N) were applied to the palatal surface of the central incisor. The maximum (σmax) and minimum (σmin) principal stress, equivalent von Mises stress (σvM), and maximum principal elastic strain (εmax) values were evaluated for the cortical and trabecular bone. Results: For cortical bone, the highest stress values (σmax and σvm) (MPa) were observed in IR (87.4 and 82.3), followed by IS (83.3 and 72.4), ER (82 and 65.1), and ES (56.7 and 51.6). For εmax, IR showed the highest stress (5.46e‐003), followed by IS (5.23e‐003), ER (5.22e‐003), and ES (3.67e‐003). For the trabecular bone, the highest stress values (σmax) (MPa) were observed in ER (12.5), followed by IS (12), ES (11.9), and IR (4.95). For σvM, the highest stress values (MPa) were observed in IS (9.65), followed by ER (9.3), ES (8.61), and IR (5.62). For εmax, ER showed the highest stress (5.5e‐003), followed by ES (5.43e‐003), IS (3.75e‐003), and IR (3.15e‐003). Conclusion: The influence of platform switching was more evident for cortical bone than for trabecular bone, mainly for the external hexagon implants. In addition, the external hexagon implants showed less stress concentration in the regular and switching platforms in comparison to the internal hexagon implants. 相似文献
998.
Marques DN da Mata AD Silveira JM Marques JR Amaral JP Guilherme NF 《Clinical oral investigations》2012,16(1):155-163
The objective of this study is to compare salivary hydrogen peroxide (HP) release kinetics and potential toxicity of systemic
exposure of four different whitening products. A double-blind, randomized controlled trial was conducted in a Portuguese dental
faculty clinic. Two hundred forty volunteers were randomized to eight intervention groups. Participants were randomly assigned
to receive active or placebo applications of one of four different products: Opalescence 10% PF™ (OPL), Vivastyle? 10%™ (VS10%),
Vivadent Paint On Plus™ (PO+), and Trés White Supreme™ (TWS). Saliva collection was obtained by established methods at different
times. The HP salivary content was determined by a photometric method. Salivary HP variations, total amount of salivary HP,
and counts of subjects above the safe daily HP dose were the main outcome measures. All whitening systems significantly released
HP to the saliva when compared to placebo, and all showed different release kinetics. The adaptable tray system (TWS) presented
a risk increase of 37% [20–54%, 95% confidence interval] when compared to the other systems. The use of an adaptable tray
whitening system with higher concentration of HP increases the toxicity potential. 相似文献
999.
Microscopic evaluation of induced tooth movement in traumatized teeth: an experimental study in rats
Alex Luiz Pozzobon Pereira Marcos Rogério de Mendonça Celso Koogi Sonoda Mauro Carlos Agner Bussato Osmar Aparecido Cuoghi Aubrey Fernando Fabre 《Dental traumatology》2012,28(2):114-120
Abstract – The clinical management of orthodontic patients with dental trauma before or during the treatment is mainly founded on clinical experience, expert opinions, and individual case reports. It is proposed in the literature that teeth sustaining mild trauma with minor damage to the periodontium (e.g. subluxation) should be followed for a period of time before being subjected to orthodontic forces. A minimum period of 3 months has been proposed. In this study, we used an animal model to investigate whether shorter observation periods could be established in case of mild trauma. The periradicular region of rat molars was examined microscopically to determine the biological events of tooth movement started 15 and 30 days after intentional subluxation using an experimental method to induce dentoalveolar trauma. Thirty adult male Wistar rats were assigned to 6 groups (n = 5): Group 1 (control – no trauma/orthodontic movement); Group 2: the animals received an orthodontic device and were sacrificed after 7 days; Groups 3 and 4: dentoalveolar trauma (subluxation) was experimentally induced by the application of an axial force of 900 cN on the occlusal surface of the maxillary right first molar, and the animals were sacrificed after 22 and 37 days, respectively; and Groups 5 and 6: 15 and 30 days, respectively, after force application, an orthodontic device was installed and the rats were sacrificed 7 days later. In G5 and G6, the periodontal ligament and pulp tissue were rich in cellular elements and blood vessels, the alveolar bone was preserved, and the root surface presented only very small areas of surface resorption (cementum), maintaining the characteristics of normality. In conclusion, the microscopic alterations in the gingival and periodontal tissues in response to an experimentally induced mild dentoalveolar trauma simulating subluxation were not sufficient to contraindicate starting the orthodontic movement 15 and 30 days after trauma. 相似文献
1000.
Neide Pena Coto Josete Barbosa Cruz Meira Reinaldo Brito e Dias Larissa Driemeier Guilherme de Oliveira Roveri Pedro Yoshito Noritomi 《Dental traumatology》2012,28(2):108-113
Abstract – There has been a significant increase in the number of facial fractures stemming from sport activities in recent years, with the nasal bone one of the most affected structures. Researchers recommend the use of a nose protector, but there is no standardization regarding the material employed. Clinical experience has demonstrated that a combination of a flexible and rigid layer of ethylene vinyl acetate (EVA) offers both comfort and safety to practitioners of sports. The aim of the present study was the investigation into the stresses generated by the impact of a rigid body on the nasal bone on models with and without an EVA protector. For such, finite element analysis was employed. A craniofacial model was constructed from images obtained through computed tomography. The nose protector was modeled with two layers of EVA (1 mm of rigid EVA over 2 mm of flexible EVA), following the geometry of the soft tissue. Finite element analysis was performed using the LS Dyna program. The bone and rigid EVA were represented as elastic linear material, whereas the soft tissues and flexible EVA were represented as hyperelastic material. The impact from a rigid sphere on the frontal region of the face was simulated with a constant velocity of 20 m s?1 for 9.1 μs. The model without the protector served as the control. The distribution of maximal stress of the facial bones was recorded. The maximal stress on the nasal bone surpassed the breaking limit of 0.13–0.34 MPa on the model without a protector, while remaining below this limit on the model with the protector. Thus, the nose protector made from both flexible and rigid EVA proved effective at protecting the nasal bones under high‐impact conditions. 相似文献