3D accuracy of implant positions in template-guided implant placement as a function of the remaining teeth and the surgical procedure: a retrospective study

Objective

The aim of this study was to investigate differences between the virtually planned and clinically achieved implant positions in completely template-guided implantations as a function of the type of edentulous space, the residual natural dentition, and the surgical implementation.

Materials and methods

Fifty-six patient cases with a total of 122 implants were evaluated retrospectively. The implantations were completely template-based. The data of the planned implant positions were overlaid with the actual clinical implant positions, followed by measurements of the 3D deviations in terms of coronal (xc) and apical distance, height (xh), and angulation (ang) and statistical analysis.

Results

The mean xc was 1.2 mm (SD 0.7 mm); the mean xa was 1.8 mm (SD 0.9 mm), the mean xh was 0.8 mm (SD 0.7 mm); and the mean ang was 4.8° (SD 3.1). The type of edentulous space and the jaw (maxilla/mandible) had no significant effect on the results in terms of implant positions. The presence of an adjacent natural tooth at the time of implantation had a significant influence on xh (p = 0.04) and ang (p = 0.05). No significant differences were found regarding the surgical approach for any of the parameters examined.

Conclusion

The results of our study are in the same range as those of other studies. Template-guided implantation offers a high degree of accuracy even in the presence of different configurations of the residual dentition or different surgical approaches. A clinical benefit is therefore present, especially from a prosthetic point of view.

Clinical relevance

The clinically achievable accuracy can be described as sufficient for further prosthetic treatment, given the intrinsic and methodological tolerances, making prosthetic rehabilitation safe and predictable.
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Influence of the oscillation frequency of different side-to-side toothbrushes on noncontact biofilm removal

Abstract

Objectives

The objective of this study was to investigate the influence of different oscillation frequencies of three powered toothbrushes with side-to-side action for noncontact biofilm removal in an artificial interdental space model.

Materials and methods

A three-species biofilm (Porphyromonas gingivalis, Fusobacterium nucleatum and Streptococcus sanguinis) was formed in vitro on protein-coated titanium disks using a flow chamber system combined with a static biofilm growth model. The oscillation frequencies of three commercial side-to-side toothbrushes were evaluated by means of a dose response. The frequency was decreased in steps (100, 85, 70, 55, and 40%). Subsequently, the biofilm-coated substrates were exposed to the side-to-side toothbrushes. The biofilm volumes were measured using volumetric analyses (Imaris 8.1.2) with confocal laser scanning microscope images (Zeiss LSM700).

Results

Compared to maximum oscillation frequency (100%), lower oscillation frequencies (up to 40%) resulted in reduced median percentages of biofilm reduction (median biofilm reduction up to 53% for maximum oscillation frequency, and up to 13% for 40% oscillation frequency) (p ≥ 0.03). In addition, decreasing the oscillation frequencies of the side-to-side toothbrushes showed an enhanced variety in the results of repeated experiments.

Conclusions

The oscillation frequency of the tested side-to-side toothbrushes affected the biofilm reduction in an interdental space model.

Clinical relevance

Within a toothbrush, higher oscillation frequencies may lead to beneficial effects on interdental biofilm removal by noncontact brushing.
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