Comparative study of bacterial microfiltration in the implant-abutment interface, with straight and conical internal connections, in vitro

Implant-Abutment Connections: A Structured Review

The aim of the study was to carry out a structured review of studies that dealt with types of implant abutment connections, the concept of platform switching and its influence on hard and soft oral tissues. Electronic search was conducted over PubMed, Google Scholar, Medline, Embase to find articles dealing with Implant abutment connection and platform switching. We came across a total of 248 articles, which were filtered to a cumulative 19 articles after cross matching with predetermined inclusion and exclusion criteria. Most of the available literature gravitates in favor of an internal connection with the incorporation of platform switching to attain satisfactory hard and soft tissue outcomes.

Evaluation of sealing efficacy and removal convenience of sealing materials for implant abutment screw access holes

Background

Sealing materials are used to fill abutment screw access holes (SAH) to prevent microleakage and protect the central screws in oral implant restoration. However, thus far, no consensus has been reached on sealing material selection. In this study, a comparison of the sealing efficacy and removal convenience of different sealing materials for cement-retained implant restoration was conducted.

Methods

Various sealing materials were classified into five groups, namely, gutta-percha (GP), temporary restorative paste (TRP), vinyl polysiloxane (VPS), polytetrafluoroethylene (PTFE) tape, and onlay resin (OR), and 35 sets of analog-abutments were allocated into five groups of seven specimens. A sealing efficacy test was conducted using a modified dye-penetration method, in which a lower absorbance indicated better sealing efficacy. For the removal-convenience test, the materials were removed from each SAH after solidification, and the retrieval time was recorded.

Results

On days 1 and 10, PTFE exhibited the highest absorbance value with significant differences compared to the other groups. On day 30, TRP and PTFE showed significantly higher absorbance values than GP, VPS, and OR, but no significant difference was detected between TRP and PTFE (p = 0.424). The absorbance values of TRP and PTFE from days 1, 10, and 30 showed significant intragroup differences, while those of the other groups did not. In terms of the removal convenience on days 1, 10, and 30, VPS achieved the best performance, followed by PTFE, OR, TRP, and GP.

Conclusion

Within the limitations of this experiment, VPS and OR showed better sealing efficacy against microleakage and a more convenient removal than the other materials; thus, VPS and OR are recommended for clinical use.

One-year outcomes of dental implants with a hybrid surface macro-design placed in patients with history of periodontitis: A randomized clinical trial

AIM

To evaluate the radiological, clinical, and microbiological outcomes of implants with a hybrid surface macro-design in patients with a history of periodontitis.

MATERIAL AND METHODS

The study was designed as a 12-month, parallel-arm, randomized controlled trial where patients with a history of treated periodontitis in need of dental implants for single-unit or short-span prosthesis were randomly allocated to a test [implants with a machined titanium surface in the coronal collar (hybrid; HS)] or a control group [conventional implants with moderately rough surface up to the implant shoulder (RS)]. Patients were followed at 3, 6, and 12 months after loading with assessment of radiological, clinical, and microbiological outcomes, as well as patient-related outcome measures (PROMs).

RESULTS

Forty patients were randomly assigned to either the RS group (n = 20) or the HS (n = 20) group. At 1 year, the mean marginal bone level changes were 0.22 [standard deviation (SD) 0.36] mm for the HS group and 0.22 (SD 0.29) mm for the RS group, with no significant differences between them (p = .961). Similarly, no significant differences in clinical, microbiological, or PROMs were observed between groups.

CONCLUSIONS

HS implants demonstrated radiographic, clinical, and microbiological characteristics equal to RS implants in patients with a history of periodontitis.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov (identifier NCT05010382).