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Optimal implant placement is essential for long-term implant survival and satisfactory prosthodontic outcomes. Autonomous dental implant robots have been reported to achieve accurate implant placement with satisfactory outcomes. This clinical report describes the use of an autonomous dental implant robot for axial and tilted implant placement in an edentulous mandible.
RESUMO
STATEMENT OF PROBLEM: Accurate placement of tilted implants is essential as they are typically close to important anatomic structures. Inaccurate implant position may damage those structures and affect outcomes. PURPOSE: The purpose of this in vitro study was to compare the accuracy and efficiency of an autonomous dental implant robotic (ADIR) system and a static computer-assisted implant surgery (sCAIS) system in placing tilted implants in edentulous patients. MATERIAL AND METHODS: Ten 3-dimensionally (3D) printed edentulous mandibular casts were assigned to 1 of 2 groups (ADIR and sCAIS). The coronal, apical, and angular deviations of the placement of tilted implants, preoperative preparation time, and surgical time were compared between the 2 groups. The paired samples t test and the independent samples t test were used to compare the groups (α=.05). RESULTS: The mean ±standard deviation of coronal, apical, and angular deviation in the ADIR group and sCAIS group were 0.47 ±0.06 mm versus 1.09 ±0.11 mm, 0.47 ±0.05 mm versus 1.53 ±0.14 mm, and 0.91 ±0.82 degrees versus 2.83 ±0.55 degrees, respectively. The deviations of the tilted implant positions in the ADIR were relatively small and significantly different from those of sCAIS (P<.05). The preoperative preparation time of the ADIR group was significantly longer than that of the sCAIS group (P<.001), and the surgical time for the 2 groups was statistically similar (P=.259). CONCLUSIONS: Compared with the sCAIS system, the deviation of tilted implants in the ADIR group was smaller, but the preoperative preparation time was longer. The results indicated that using the ADIR for tilted implantation can lead to more accurate implantation positions and reduce the occurrence of complications. However, it is time consuming, and the workflow should be simplified to improve efficiency.
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Amorphous carbon (a-C) film is a promising candidate for metallic implant surface coatings to improve corrosion resistance and osteogenesis in vivo. However, the molecular mechanism of how the bioinert carbon can induce osteogenesis has not been elucidated yet. In the present study, an a-C film was deposited on a smooth pure titanium (Ti) implant surface (C-Ti) by a vacuum evaporator. The scanning electron microscopy (SEM) observation showed a homogeneous coating with dispersed granules on the C-Ti surface. Raman spectroscopy revealed the standard a-C shift bands. Rat bone marrow mesenchymal stem cells (MSCs) were cultured on different implant surfaces. In agreement with other publications, the C-Ti surface exhibited enhanced cell adhesion, proliferation and osteogenic differentiation. In addition, a western blot analysis of the mitogen-activated protein kinase (MAPK) signaling pathways revealed that only the p38 phosphorylation level was increased significantly on the C-Ti surface. Inhibition of p38 by SB203580 obliterated the enhanced osteogenic differentiation ability of the C-Ti surface. Furthermore, integrin-linked kinase (ILK) was significantly upregulated on the C-Ti surface during the initial three days. Specific knockdown of ILK by siRNA sharply decreased p38 phosphorylation and also resulted in reduced osteogenic differentiation on the C-Ti surface. Above all, our study indicates that the a-C coating is able to promote osteogenic differentiation of MSCs through the ILK/p38 signaling pathway.