Fracture Resistance Of Implants Research Articles

The effect of implantoplasty on dental implant fracture resistance: a systematic review

An increase in dental implant placements in recent years has seen a growth in the reported cases of post-operative complications such as peri-implantitis. One of the available treatment modalities to overcome such complications is implantoplasty. Although this procedure is not new, the long-term effect of implantoplasty has not been addressed extensively. The aim of this systematic review was to investigate the change in fracture resistance of dental implants after implantoplasty. Three electronic databases and reference lists of included studies were searched to assess the potential effect of implantoplasty on implant fracture resistance. Titles and abstracts were screened by two reviewers in parallel. The extracted information regarding implant fracture resistance was reported based on the guidelines set by the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. A total of 56 studies were identified, of which, nine studies were included. Narrow platform implants (<3.75 mm) were more susceptible to fracture following implantoplasty compared to wider platforms (?5 mm). Implants with internal hexagon connection may have a higher risk of fracture after implantoplasty compared to other connection designs such as external hexagon and conical connections. Other potential factors which may affect implant fracture resistance after implantoplasty include crown to implant ratio, implant material, and the amount of peri-implant bone loss. Within the limitation of in vitro studies, there is no clear evidence to demonstrate the effect of implantoplasty on implant fracture resistance. Methodological differences between the available studies did not allow for clear comparison between them. Furthermore, the limited amount of clinical reports of this resective procedure, in combination with patient and operator variability, affect the clinical assessment of this treatment modality.

Effects of different switched or not-switched implant and abutment platform designs and marginal bone loss on fracture strength: An in vitro study

Statement of problemThe use of reduced platform sets (implants and abutments) can help to control crestal bone loss around implants, which is essential for optimizing esthetics and biomechanical behavior. However, the information available on the fracture resistance of implants with a reduced platform is sparse. PurposeThe purpose of this in vitro study was to analyze the maximum fracture strength value of implants with different platform designs during quasistatic fatigue, followed by a simulation of different bone levels of cervical insertion. Material and methodsOne hundred and twenty sets of dental implants and abutments with different diameters and platform designs were tested. All implants had an internal hexagon connection and conical macrogeometry. Four groups (n=30) were studied: Ø4.0-mm implants with a regular matched platform (rMatch group), Ø4.0-mm implants with a regular switched platform (PSwitch group), Ø5.0-mm implants with a wide matched platform (wMatch group), and Ø5.0-mm implants with a wide switched platform (wSwitch group). Three conditions simulating different levels of bone position around the cervical portion of the implants were proposed: insertion at the implant shoulder level=0 mm (L0), level=3 mm of insertion loss (L3), and level=5 mm of insertion loss (L5). All sets of all groups and proposed insertion level were subjected to a fracture strength test at 30 degrees in relation to the axis of the sets in a universal testing machine. ResultsRegardless of the insertion levels tested, the switched platform implants (rSwitch and wSwitch groups) showed similar mean fracture strength values (P>.05), while the implants of matched platforms (rMatch and wMatch groups) showed different fracture strength values for all insertion levels tested (P<.001). ConclusionsThe fracture strength values of the switched platform implants were lower at all insertion levels tested. However, for all insertion levels tested, the implants with a switched platform presented less deformation, whereas, in the matched platform implants, there was significant deformation of the implant structure.

Implantoplasty: Carbide burs vs diamond sonic tips. An in vitro study

Implantoplasty (IP) is a treatment option for peri-implantitis. Mechanical concerns were raised on fracture resistance of implants subjected to this procedure. This study aimed to compare two methods of IP in terms of implant wear and fracture resistance, and of surface topography. Eighteen cylindrical screw-shaped dental implants (4mm diameter, 13mm length) with an external hexagonal connection were used. IP was performed on the first 6-mm implant surface with a sequence of burs or diamond sonic tips, both followed by an Arkansas finishing. IP duration and implant weight variation were recorded. Micro-computed tomography (micro-CT) was used to evaluate material loss. Implant fracture resistance was assessed by static compression test. Surface topography analysis was performed with a stylus profilometer. Scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS) was applied for implant surface morphology and elemental characterization. Micro-CT showed less material loss in sonic compared to burs. No statistically significant difference was found between the mean fracture resistance values reached in bur and sonic, both followed by Arkansas, and with respect to control. IP performed with burs led to a smoother surface compared to sonic. Equivalent final surface roughness was found after Arkansas in both IP procedures. SEM-EDS showed a deburring effect associated to sonic and revealed carbon and aluminum peaks attributable to contamination with sonic diamond tips and Arkansas bur, respectively. IP with sonic diamond tips was found to be more conservative in terms of structure loss. This could have a clinical relevance in case of narrow-diameter implants.

Effect of bone loss on the fracture resistance of narrow dental implants after implantoplasty. An in vitro study.

Background Implantoplasty (IP) involves polishing of the exposed surface of implants affected by peri-implantitis (PI). A study was made to determine whether the degree of bone loss influences the fracture resistance of implants with or without IP.Material and Methods An in vitro study was carried out on 32 narrow (3.5 mm) dental implants with a rough surface and external hexagonal connection. Implantoplasty was performed in half of the implants of the sample. Both the IP and control implants were divided into two subgroups according to the amount of bone loss (3 mm or 7.5 mm). Standardized radiographic assessment of implant width was performed using specific software. The main outcome variable was the maximum compression force (Fmax) of implants when subjected to static resistance to fracture tests. Implant fractures were subsequently analyzed by scanning electron microscopy. A descriptive and bivariate analysis of the data was performed.Results Significant changes in implant width were observed after IP (p<0.05). No significant differences between IP and control implants were recorded in terms of the Fmax values in the two bone loss subgroups (3 mm: control 854.37N 195.08 vs. IP 752.12N 186.13; p=0.302, and 7.5 mm: control 548.82N 80.02 vs. IP 593.69N 111.07; p=0.370). Greater bone loss was associated to a decrease in Fmax, which proved significant for the control implants (p=0.001). Fractures were more frequently located in the platform (n=13).Conclusions Implants with more apical bone levels appear to be more susceptible to fracture. On the other hand, IP does not seem to significantly decrease the fracture resistance of narrow (3.5 mm) platform dental implants with external hexagonal connections. The fact that most fractures occur in the platform area indicates that the latter is exposed to more mechanical stress. Key words:Peri-implantitis, dental implants, compressive strength, titanium, implantoplasty.

Effect of crown to implant ratio and implantoplasty on the fracture resistance of narrow dental implants with marginal bone loss: an in vitro study

BackgroundPeri-implantitis is a biological complication that affects soft and hard tissues around dental implants. Implantoplasty (IP) polishes the exposed implant surface, to decontaminate it and make it less prone to bacterial colonization. This study investigates whether a higher clinical crown-to-implant-ratio (CIR) reduces implant fracture resistance and whether implants are more fracture-prone after IP in the presence of 50% of bone loss.MethodsForty-eight narrow platform (3.5 mm) 15 mm long titanium dental implants with a rough surface and hexagonal external connection were placed in standardized bone-like resin casts leaving 7.5 mm exposed. Half were selected for IP. The IP and control groups were each divided into 3 subgroups with different clinical CIRs (2:1, 2.5:1 and 3:1). The implant wall width measurements were calculated using the software ImageJ v.1.51 through the analysis of plain x-ray examination of all the samples using standardized mounts. A fracture test was performed and scanning electron microscopy was used to evaluate maximum compression force (Fmax) and implant fractures.ResultsIP significantly reduced the implant wall width (P < 0.001) in all reference points of each subgroup. Fmax was significantly higher in the 2:1 subgroup (control = 1276.16 N ± 169.75; IP = 1211.70 N ± 281.64) compared with the 2.5:1 (control = 815.22 N ± 185.58, P < 0.001; IP = 621.68 N ± 186.28, P < 0.001) and the 3:1 subgroup (control = 606.55 N ± 111.48, P < 0.001; IP = 465.95 N ± 68.57, P < 0.001). Only the 2.5:1 subgroup showed a significant reduction (P = 0.037) of the Fmax between the controls and the IP implants. Most fractures were located in the platform area. Only 5 implants with IP of the 2:1 CIR subgroup had a different fracture location (4 fractures in the implant body and 1 in the prosthetic screw).ConclusionsIP significantly reduces the fracture resistance of implants with a 2.5:1 CIR. The results also suggest that the CIR seems to be a more relevant variable when considering the resistance to fracture of implants, since significant reductions were observed when unfavorable CIR subgroups (2.5:1 and 3:1 CIR) were compared with the 2:1 CIR samples.

A Comparative Analysis of Implants Presenting Different Diameters: Extra-Narrow, Narrow and Conventional.

This study aimed at performing a comparative analysis of the fracture resistance of implants, evaluating extra-narrow, narrow, and regular implants. Four groups containing 15 implants each were evaluated. Group 1 (G1): single-piece extra-narrow implants; Group 2 (G2): single-piece narrow implants; Group 3 (G3): Morse taper narrow implants with solid abutments; Group 4 (G4): Morse taper conventional implants with solid abutments. The implants were tested using a universal testing machine for their maximum force limit and their maximum bending moment. After obtaining the data, the Shapiro–Wilk, ANOVA, and Tukey (p < 0.05) statistical tests were applied. Samples from all the groups were analyzed by scanning electron microscopy and Groups 3 and 4 were analyzed by profilometry. The means and the standard deviation values for the maximum force limit (N) and the maximum bending moment (Nmm) were respectively: G1:134.29 N (10.27); G2:300.61 N (24.26); G3:360.64 N (23.34); G4:419.10 N (18.87); G1:1612.02 Nmm (100.6); G2:2945 Nmm (237.97); G3:3530.38 Nmm (228.75); G4:4096.7 Nmm (182.73). The groups behaved statistically different from each other, showing that the smallest diameter implants provided less fracture resistance, both in the tensile strength tests and in the maximum bending moment between all groups. Furthermore, single-piece implants, with 2.5 mm and 3.0 mm diameters, deformed in the implant body region area, rather than in the abutment region.

Comparison of the fracture resistance of dental implants with different abutment taper angles

To investigate the effects of abutment taper angles on the fracture strength of dental implants with TIS (taper integrated screwed-in) connection. Thirty prototype cylindrical titanium alloy 5.0mm-diameter dental implants with different TIS-connection designs were divided into six groups and tested for their fracture strength, using a universal testing machine. These groups consisted of combinations of 3.5 and 4.0mm abutment diameter, each with taper angles of 6°, 8° or 10°. 3-Dimensional finite element analysis (FEA) was also used to analyze stress states at implant–abutment connection areas. In general, the mechanical tests found an increasing trend of implant fracture forces as the taper angle enlarged. When the abutment diameter was 3.5mm, the mean fracture forces for 8° and 10° taper groups were 1638.9N±20.3 and 1577.1N±103.2, respectively, both larger than that for the 6° taper group of 1475.0N±24.4, with the largest increasing rate of 11.1%. Furthermore, the difference between 8° and 6° taper groups was significant, based on Tamhane's multiple comparison test (P<0.05). In 4.0mm-diameter abutment groups, as the taper angle was enlarged from 6° to 8° and 10°, the mean fracture value was increased from 1066.7N±56.1 to 1241.4N±6.4 and 1419.3N±20.0, with the largest increasing rate of 33.1%, and the differences among the three groups were significant (P<0.05). The FEA results showed that stress values varied in implants with different abutment taper angles and supported the findings of the static tests. In conclusion, increases of the abutment taper angle could significantly increase implant fracture resistance in most cases established in the study, which is due to the increased implant wall thickness in the connection part resulting from the taper angle enlargement. The increasing effects were notable when a thin implant wall was present to accommodate wide abutments.