RESUMO
STATEMENT OF PROBLEM: Misfits at the implant-prosthesis interface may compromise implant-supported prostheses. Periapical radiographs are frequently used to detect misfit and can be obtained by using digital or film-based systems; however, which radiographic acquisition method and visualization software program provides the greatest accuracy is unclear. PURPOSE: The purpose of this ex vivo study was to evaluate the influence of 3 radiographic acquisition methods (complementary metal oxide semiconductor [CMOS] sensor, phosphor plates, and radiographic films) and 2 visualization software programs (proprietary and third-party) on the detection of misfits at the implant-prosthesis interface. MATERIAL AND METHODS: Thirty-two dental implants were placed in dry human mandibles. Misfits were simulated by inserting a 50-µm polyester strip at the implant-prosthesis interface; prosthetic crowns installed directly over the implant platforms were considered as controls. Standard parallel periapical radiographs were obtained by using a CMOS sensor, a phosphor plate, and radiographic films. Five dentists assessed the digital radiographs for the presence or absence of misfits at the implant-prosthesis interface by using the proprietary software program and a third-party software program; film-based radiographs were evaluated on a light box. The area under the receiver operating characteristic curves (Az values) were compared (α=.05); sensitivity, specificity, accuracy, positive predictive value, and negative predictive values were also estimated. RESULTS: All diagnostic and Az values were higher for the phosphor plate than for the CMOS sensor and the film-based methods (P<.05), regardless of the viewing software program used (proprietary or third-party) (P>.05). CONCLUSIONS: The use of phosphor plates positively influenced the diagnostic accuracy for the detection of misfits at the implant-prosthesis interface, irrespective of the viewing software program used.
Assuntos
Implantes Dentários , Dente , Coroas , Prótese Dentária Fixada por Implante , Humanos , Mandíbula , SoftwareRESUMO
STATEMENT OF PROBLEM: A misfit or gap at the implant-abutment joint (IAJ) requires detection as it may compromise the health of the peri-implant tissue. However, which radiographic technique provides the most orthogonal relationship between the central beam and the implant/image receptor is unclear. PURPOSE: The purpose of this in vitro study was to evaluate the diagnostic accuracy of 4 intraoral radiographic techniques on misfit detection at the IAJ. MATERIAL AND METHODS: Twenty implants were placed in polyamide jaws, and customized dental implant abutments with a metal collar were installed. Different gaps were simulated by placing one or three 50-µm-thick polyester strips at the IAJ; the absence of the strip represented the control group (no gap). The 4 radiographic techniques were evaluated by using different film holders: a periapical with bisecting angle (PBA), a bitewing interproximal (BI), a periapical with standard paralleling (PSP), and a periapical with modified paralleling (PMP) holder (with a custom-made paralleling index). A total of 240 digital radiographs were evaluated by 4 clinicians experienced with dental implants. Differences were evaluated by using receiver operating characteristic (ROC) curves (Az) and Fisher tests (α=.05). Diagnostic values (sensitivity, specificity, accuracy, and positive and negative predictive values) were also obtained. The Kappa test was used to assess intra- and interevaluator reproducibility, which ranged from moderate to almost perfect. RESULTS: All diagnostic values, except specificity, were lower for the PBA technique for both the 50- and 150-µm gaps. Az values for the PBA technique were significantly lower than those obtained for the other 3 techniques (P<.05), which did not differ from each other. The 150-µm gaps were more easily detected than the 50-µm gaps only for PBA (P<.05). CONCLUSIONS: The BI, PSP, and PMP techniques detected misfits at the IAJ most accurately. The PBA technique is not recommended for this purpose.