Effect of splinted and nonsplinted impression techniques on the accuracy of fit of fixed implant prostheses in edentulous patients: a comparative study

Department of Restorative Dentistry and Biomaterials Sciences, Harvard School of Dental Medicine, Boston, Massachusetts 02115, USA.
The International journal of oral & maxillofacial implants (Impact Factor: 1.45). 11/2011; 26(6):1267-72.
Source: PubMed


The effect of different implant impression techniques on the accuracy of casts has been investigated mostly in vitro, and clinically relevant evidence is scarce. The purpose of this study was to investigate the effect of implant impression techniques--specifically, splinted versus nonsplinted--on the accuracy of fit of fixed implant prostheses in edentulous patients.
This clinical study included 12 edentulous patients (13 edentulous arches). All patients had undergone computer-guided, prosthetically driven implant surgery. Splinted (with acrylic resin) and nonsplinted pickup implant impression techniques were used to generate two different casts. Intraoral verification jigs were made to fabricate a third index cast (prosthesis fabrication cast); these made up a control group. All patients were definitively rehabilitated with one-piece zirconia prostheses. The accuracy of fit of each prosthesis was evaluated indirectly by examining them clinically and radiographically while they were fit on the generated casts.
Of the 13 splinted casts, 12 presented with accurate clinical fit when the zirconia prosthesis was seated on its respective cast. Only 6 of the 13 nonsplinted casts showed accurate clinical fit. The zirconia prostheses fit accurately on all respective casts of the control group (prosthesis fabrication cast) as well as intraorally. The differences between the test groups and between the nonsplinted and control groups were statistically significant. No statistically significant differences were found between the splinted and control groups.
There is clinical evidence that the splinted impression technique generates more accurate implant impressions and master casts than the nonsplinted technique for complete-arch, one-piece fixed prostheses.

Download full-text


Available from: Panos Papaspyridakos, Aug 28, 2014
  • Source
    • "If all four measurements at each implant–abutment junction were accurate, then the fit was judged as accurate (prosthesis level). If one or more of the four measurements were not accurate, the fit was deemed not accurate (Papaspyridakos et al. 2011). The k-score for interexaminer agreement was 0.95 for all measurements, showing near perfect interexaminer agreement. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Purpose: The aim of this study was to assess the effect of connection type and impression technique on the accuracy of fit of implant-supported fixed complete-arch dental prostheses (IFCDPs). Materials and methods: An edentulous mandibular cast with five implants was fabricated to serve as master cast (control) for both implant- and abutment-level baselines. A titanium one-piece framework for an IFCDP was milled at abutment level and used for accuracy of fit measurements. Polyether impressions were made using a splinted and non-splinted technique at the implant and abutment level leading to four test groups, n = 10 each. Hence, four groups of test casts were generated. The impression accuracy was evaluated indirectly by assessing the fit of the IFCDP framework on the generated casts of the test groups, clinically and radiographically. Additionally, the control and all test casts were digitized with a high-resolution reference scanner (IScan D103i, Imetric, Courgenay, Switzerland) and standard tessellation language datasets were generated and superimposed. Potential correlations between the clinical accuracy of fit data and the data from the digital scanning were investigated. To compare the accuracy of casts of the test groups versus the control at the implant and abutment level, Fisher's exact test was used. Results: Of the 10 casts of test group I (implant-level splint), all 10 presented with accurate clinical fit when the framework was seated on its respective cast, while only five of 10 casts of test group II (implant-level non-splint) showed adequate fit. All casts of group III (abutment-level splint) presented with accurate fit, whereas nine of 10 of the casts of test group IV (abutment-level non-splint) were accurate. Significant 3D deviations (P < 0.05) were found between group II and the control. No statistically significant differences were found between groups I, III, and IV compared with the control. Implant connection type (implant level vs. abutment level) and impression technique did affect the 3D accuracy of implant impressions only with the non-splint technique (P < 0.05). Conclusion: For one-piece IFCDPs, the implant-level splinted impression technique showed to be more accurate than the non-splinted approach, whereas at the abutment-level, no difference in the accuracy was found.
    Full-text · Article · Sep 2015 · Clinical Oral Implants Research
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Background The treatment of mandibular edentulism with implant fixed complete dental prostheses (IFCDPs) is a routinely used treatment option. PurposeThe study aims to report the implant and prosthodontic survival rates associated with IFCDPs for the edentulous mandible after an observation period of a minimum 5 years. Materials and Methods An electronic MEDLINE/PubMED search was conducted to identify randomized controlled clinical trials and prospective studies with IFCDPs for the edentulous mandible. Clinical studies with at least 5-year follow-up were selected. Pooled data were statistically analyzed and cumulative implant- and prosthesis survival rates were calculated by meta-analysis, regression, and chi-square statistics. Implant-related and prosthesis-related factors were identified and their impact on survival rates was assessed. ResultsSeventeen prospective studies, including 501 patients and 2,827 implants, were selected for meta-analysis. The majority of the implants (88.5% of all placed implants) had been placed in the interforaminal area. Cumulative implant survival rates for rough surface ranged from 98.42% (95% confidence interval [CI]: 97.98-98.86) (5 years) to 96.86% (95% CI: 96.00-97.73) (10 years); smooth surface implant survival rates ranged from 98.93% (95% CI: 98.38-99.49) (5 years) to 97.88% (95% CI: 96.78-98.98) (10 years). The prosthodontic survival rates for 1-piece IFCDPs ranged from 98.61% (95% CI: 97.80-99.43) (5 years) to 97.25% (95% CI: 95.66-98.86) (10 years). Conclusion Treatment with mandibular IFCDPs yields high implant and prosthodontic survival rates (more than 96% after 10 years). Rough surface implants exhibited cumulative survival rates similar to the smooth surface ones (p>.05) in the edentulous mandible. The number of supporting implants and the antero-posterior implant distribution had no influence (p>.05) on the implant survival rate. The prosthetic design and veneering material, the retention type, and the loading protocol (delayed, early, and immediate) had no influence (p>.05) on the prosthodontic survival rates.
    Full-text · Article · Jan 2013 · Clinical Implant Dentistry and Related Research
  • [Show abstract] [Hide abstract]
    ABSTRACT: To report the clinical results and technical complications with computer-assisted design/computer-assisted manufacturing (CAD/CAM) zirconia, implant fixed complete dental prostheses (IFCDPs) after 2–4 years in function. Fourteen consecutive edentulous patients (16 edentulous arches) were included in this study. Ten of the patients were women and four were men, with an average age of 58 years (range: 35–71). Ten mandibular and six maxillary arches were restored with porcelain fused to zirconia (PFZ) IFCDPs. Of the 16 arches, 14 received one-piece and 2 received segmented two-piece IFCDPs, respectively. The mean clinical follow-up period was 3 years (range: 2–4). At the last recall appointment, biological and technical parameters of dental implant treatment were evaluated. The implant and prosthesis survival rate following prosthesis insertion was 100% up to 4-year follow-up. The prostheses in 11 of the 16 restored arches were structurally sound, exhibited favorable soft tissue response, esthetics, and patient satisfaction. Five IFCDPs (31.25%) in four patients exhibited porcelain veneer chipping. Chipping was minor in three prostheses (three patients) and was addressed intraorally with polishing (one prosthesis) or composite resin (two prostheses). One patient with maxillary and mandibular zirconia IFCDP exhibited major porcelain chipping fractures which had to be repaired in the laboratory. Function, esthetics, and patient satisfaction were not affected in three of the four fracture incidents. Median crestal bone loss was 0.1 mm (0.01–0.2 mm). The presence of parafunctional activity, the IFCDP as opposing dentition, and the absence of occlusal night guard were associated with all the incidents of ceramic chipping. CAD/CAM zirconia IFCDPs are viable prosthetic treatment after 2–4 years in function, but not without complications. The porcelain chipping/fracture was the most frequent technical complication, with a 31.25% chipping rate at the prosthesis level. Despite the technical complications, increased patient satisfaction was noted.
    No preview · Article · Jun 2013 · Clinical Oral Implants Research
Show more