Influence Of Abutment Material Research Articles

Influence of abutment material on peri-implant clinical parameters: a prospective study

Objective: This study evaluated the peri-implant clinical parameters of zirconia versus metallic abutments for standardized custom-made implantsupported single-tooth restorations. Material and Methods: Sixteen subjects received 30 dental implants on esthetic region of upper jaws. Test group had 14 implant-supported single-tooth restorations with ceramic abutment and control group had 16 restorations with metallic abutment. Peri-implant clinical parameters were recorded after 110 ± 10 days in function at six sites by each implant, in each subject. The means of clinical measures: probing depth (PD) and clinical attachment level (CAL); mean of percentages of sites with visible plaque (VP), bleeding on probing (BOP) and suppuration (SU) were recorded to each subject. To verify differences between groups Mann Whitney U-test was selected PD and CAL and k-light test VP, BOP and SU. Results: One zirconia implant-supported single-tooth restoration fractured at insertion time. The mean of PD, CAL, and BOP of the samples sites were lower to test group than control (p < 0.05). There were no differences of mean levels of VP and S between test and control group (p > 0.05). Conclusion: Clinical parameters around implant-supported restorations were influenced by abutment type with better results to zirconia abutments, at least, after short time period evaluation.

Influence of abutment material and luting cements color on the final color of all ceramics

Purpose. The purpose of this study is to evaluate the effects of different abutment materials and luting cements color on the final color of implant-supported all-ceramic restorations. Materials and methods. Ten A2 shade IPS e.max Press disc shape all-ceramic specimens were prepared (11 × 1.5 mm). Three different shades (translucent, universal and white opaque) of disc shape luting cement specimens were prepared (11 × 0.2 mm). Three different (zirconium, gold-palladium and titanium) implant abutments and one composite resin disc shape background specimen were prepared at 11 mm diameter and appropriate thicknesses. All ceramic specimens colors were measured with each background and luting cement samples on a teflon mold. A digital spectrophotometer used for measurements and data recorded as CIE L*a*b* color co-ordinates. An optical fluid applied on to the samples to provide a good optical connection and measurements on the composite resin background was saved as the control group. ΔE values were calculated from the ΔL, Δa and Δb values between control and test groups and data were analyzed with one-way variance analysis (ANOVA) and mean values were compared by the Tukey HSD test (α = 0.05). Results. One-way ANOVA of ΔL, Δa, Δb and ΔE values of control and test groups revealed significant differences for backgrounds and seldom for cement color groups (p the 0.05). Only zirconium implant abutment groups and gold palladium abutment with universal shade cement group were found to be clinically acceptable (ΔE ≤ 3.0). Conclusion. Using titanium or gold-palladium abutments for implant supported all ceramics will be esthetically questionable and white opaque cement will be helpful to mask the dark color of titanium abutment.

Influence of abutment material on the stress of implant-supported all-ceramic single crown

In order to investigate the influence of abutment material on the stress of implant-supported all-ceramic single crown, a 3D finite element model of implant-supported mandibular first premolar was computed by COSMOS/M 2.85 software. Alumina, zirconia, and titanium were used as abutment materials respectively. Vertical 600 N and horizontal 225 N load was applied on the occlusal surface. The results show that the stress distribution of implant-supported single crown was similar for different abutment materials. Maximum stresses within the crown were higher when titanium abutment was used. Maximum stress of titanium abutment was lower than that of ceramic abutment. Within the screw and fixture, maximum stresses had no difference under vertical loading but higher as titanium abutment was used under horizontal loading. There was no difference of maximum stress within the bone when different abutment materials were used. The present findings indicate that the abutment material had no influence on the stress distribution of implant-supported allceramic single crown but maximum stress when the titanium abutment was lower than that of ceramic abutment.

Influence of abutment material on the gingival color of implant-supported all-ceramic restorations: a prospective multicenter study

The aim of this clinical research on implant-supported restorations is to analyze, through spectrophotometric digital technology, the influence of the abutment material on the color of the peri-implant soft tissue. Twenty patients received an endosseous dental implant in the anterior maxilla. At the time of each definitive prosthesis delivery, an all-ceramic crown has been tried on gold, titanium and zirconia abutment. After the insertion of each single abutment, the peri-implant soft tissue color has been measured through a spectrophotometer. Also, the thickness of the facial peri-implant soft tissue was measured at the level of the implant neck through a caliper. A specific software has been utilized to identify a specific tissue area and to collect the data before the statistical analysis in Lab* color space. The normality of the quantitative variables was verified by means of the Shapiro-Wilk test. Simple linear correlation between quantitative variables was evaluated by using Pearson's coefficient. The results on the performance of the abutment materials with regard to the color measurements and the overall measurement ΔE were described by computing the least-square means. The significance of differences among types of abutment was verified by means of the Scheffe test for multiple comparisons. For all the abutments used, the color of the peri-implant soft tissue appeared to be significantly different from the one of the contra-lateral tooth (ΔE>8.5). Significantly higher (P<0.05) difference were present with the use of titanium abutments (11 ± 0.4) when compared with the results of gold (8.9 ± 0.4) and zirconia (8.5 ± 0.4) abutments. No correlation has been demonstrated between soft tissue thickness and degree of color difference (P>0.25). Within the limitation of the present study, the peri-implant soft tissue color appears to be different from the soft tissue color around natural teeth, no matter which type of restorative material is selected. When titanium abutment was selected, significantly higher differences were present than those obtained with gold or zirconia abutments. The thickness of the peri-implant soft tissue did not appear to be a crucial factor in the abutment impact on the soft tissue color.

Influence of abutment material on the fracture strength and failure modes of abutment-fixture assemblies when loaded in a bio-faithful simulation

The aim of the present study was to evaluate differences in the ultimate fracture resistance of titanium and zirconia abutments. Twenty titanium fixtures were embedded in 20 resin mandible section simulators to mimic osseointegrated implants in the premolar area. The embedded implants were then randomly divided into two groups. Afterwards, specimens in group A (n=10) were connected to titanium abutments (TiDesign™ 3.5/4.0, 5.5, 1.5 mm), while specimens in group B (n=10) were connected to zirconia abutments (ZirDesign ™ 3.5/4.0, 5.5, 1.5 mm). Both groups were loaded to failure in a dynamometric testing machine. Fractured samples were then analyzed by scanning electron microscopy (SEM). Group A showed a significantly higher fracture strength than that observed in group B. Group A failures were observed at the screw that connects the abutment with the implant while the abutment connection hexagons were plastically bent by the applied load. Group B failures were a result of abutment fractures. SEM analysis showed that in group A the screw failure was driven by crack nucleation, coalescence and propagation, while in group B, the SEM analysis of failed surfaces showed the conchoidal fracture profile characteristic of brittle materials. The strength of both tested systems is adequate to resist physiologic chewing forces in the premolar area. Conversely, the titanium and zirconia failure modes evaluated here occurred at unphysiological loads. In addition, because the abutments were tested without crowns, the presented data have limited direct transfer to the clinical situation.