ABSTRACT
Objetivou-se verificar a ocorrência de distorção em imagens obtidas por meio de radiografias periapicais pela técnica da bissetriz. Foram utilizadas 64 radiografias periapicais, padronizadas e digitalizadas, obtidas pela técnica periapical da bissetriz de pacientes submetidos à colocação de implantes. Após a obtenção das imagens, os implantes foram mensurados pelo método de medida digital por meio do programa ImageJ, em seu comprimento e em 3 medidas transversais ao longo de seu eixo. Os dados foram tabulados e analisados estatisticamente pelo teste T pareado. Evidenciou-se distorção de ampliação nas imagens obtidas, sendo maior na arcada superior do que na inferior. As maiores ampliações foram observadas no comprimento do implante, seguido pelo diâmetro da plataforma, diâmetro do corpo e diâmetro apical, respectivamente. Concluiu-se que há distorção importante nas imagens radiográficas obtidas pela técnica periapical da bissetriz, devendo existir o devido cuidado com tal técnica, já que essa discrepância de medida afeta o planejamento, o que pode ocasionar lesão de estruturas anatômicas importantes ou gerar engano na quantidade de possíveis perdas ósseas verticais e horizontais após a instalação do implante (AU).
This study aimed to verify the occurrence of distortion in images obtained by bisecting-angle periapical radiography. We used 64 periapical radiographs, standardized and digitalized, obtained by bisecting-angle periapical technique of patients undergoing implants insertion. After images obtainment, the implants were measured by digital measurement method through ImageJ program, in length and in three cross-cuting measures along its axis. The data were organized and statistically analyzed by paired T test. It was shown distortion of magnification in obtained images, being higher in superior arcade than in inferior. The higher magnifications were observed in length of the implant, followed by the platform diameter, body diameter, and apical diameter, respectively. It was concluded that the significant distortion in the radiographic images was taken by the bisecting-angle periapical technique and there should be proper care of such technique, since this discrepancy of measure affects the planning, which can cause injury to anatomical structures or generate major mistake in the amount of possible vertical and horizontal bone loss after installation of the implant (AU).
Subject(s)
Humans , Comparative Study , Radiography, Dental/instrumentation , Dental Implants , Brazil , Diagnostic Imaging/methods , Statistics, NonparametricABSTRACT
BACKGROUND: The prosthetic treatment in cleft patients is challenging. Based on this, the aim of this study was to evaluate the longevity of prosthetic rehabilitation treatment with implant-supported overdenture (IOD) and implant-supported fixed denture (IFD) in cleft lip and palate patients in a period of 22 years. MATERIALS AND METHODS: The medical records of 72 patients were analyzed (29 males and 43 females), and the survival rate of the implants was evaluated. Moreover, the prostheses' time of use and the reason for the changing of these were also evaluated. RESULTS: Four-hundred-seventeen implants were installed, and 370 implants survive today. The mean survival time of the implants was 7.6 years. Regarding the 97 prostheses made, the time of average use was 3.28 for the IFDs and 3.92 for IODs. The reasons for the replacements of the prostheses were mainly: fracture of the acrylic base (29.6%) and loss of vertical dimension of occlusion (VDO) (18.5%) in the IFDs. Moreover, in IODs, these were accounted for the loss of VDO due to teeth damage (17.2%) and implant loss (14.6%). CONCLUSIONS: The maintenance of the prostheses was challenging because the patients had difficulties returning for periodic control, but this fact did not result in the decrease of the success rate of the implants. The longevity of implants and prostheses was satisfactory; however, the prostheses showed repetitions mainly due to the wear of the teeth, with decreased vertical dimension and fracture of acrylic base.
ABSTRACT
Implantes estreitos de titânio surgiram na Implantodontia com a indicação clássica de serem utilizados para substituição de incisivos laterais superiores, incisivos inferiores, espaços edêntulos pequenos e com baixa incidência de carga mastigatória. Porém, na literatura encontra-se relatos de falhas mecânicas e biológica desses implantes, quando utilizados em situações de maior incidência de carga mastigatória, como em caninos e molares. Para permitir uma ampliação das indicações dos implantes de diâmetro reduzido, uma nova liga foi desenvolvida com objetivo de compensar as deficiências relatada. Os novos implantes estreitos são confeccionados a partir de uma liga de titânio e zircônia (TiZr), com 13-17% de zircônia em sua composição e possuem 3,3 mm de diâmetro. A nova liga apresenta maior resistência do que os implantes de titânio grau IV e melhor biocompatibilidade que as ligas de Ti-6Al-4V. Assim, vem sendo uma alternativa viável para ampliar as indicações clássicas dos implantes estreitos convencionais. No caso apresentado, o implante estreito de TiZr foi utilizado em região de segundo molar inferior como pilar de uma prótese fixa de 4 elementos, a fim de permitir a reabilitação de uma paciente que possuía perda óssea vertical severa, necessitando o implante tangenciar do nervo alveolar inferior. O controle foi feito durante 15 meses sem apresentar qualquer complicação, sendo assim, concluiu-se que os implantes estreitos de TiZr podem ser utilizados em espaços edêntulos reduzidos e táboa óssea fina, independente do dente a ser substituído
Narrow titanium implants came with the classic indication for use for replacement of maxillary lateral incisors, lower incisors and small edentulous spaces with low incidence of masticatory load. However, the literature reports biological and mechanical failures of these implants when used in situations of higher incidence of masticatory load, such as canines and molars. To amplify the indication of small diameter implants, a new alloy was developed in order to compensate for the deficiencies reported. The new narrow implants are made from an alloy of titanium and zirconium (TiZr) with 13-17% of zirconia in their composition and have 3.3 mm diameter. The new alloy has higher resistance than the titanium implants grade IV and better biocompatibility than the alloy Ti-V-6Al4, therefore it has being a viable alternative to broaden the classical indications of narrow conventional implants. In the case reported, the Strait of TiZr implant was used in the region of the second molar as an abutment for a fixed prosthesis in the four elements in order to allow the rehabilitation of a patient with severe vertical bone loss requiring that the implant was tangent to lower alveolar nerve. The control was carried out for 15 months without any complications, and therefore, it was concluded that the narrow TiZr implants can be used in reduced edentulous spaces and thin bone, independent of the tooth to be replaced
