Immediately loaded mini-implants supporting mandibular overdentures: A one-year comparative prospective cohort study.

BACKGROUND: Little is known about differences between mini-implants and conventional immediately loaded implants for overdentures. OBJECTIVES: To compare clinical outcomes using two immediately loaded conventional or mini-implants for mandibular overdentures. MATERIALS AND METHODS: Edentulous patients receiving either conventional (4.1 mm) or mini-implants (2.9 mm or less), based on available bone width were analyzed. All implants were immediately loaded with mandibular overdentures installed using locator attachments. Digital periapical radiographs for measuring marginal bone loss and clinical outcomes (ie, periodontal probing, plaque, and bleeding indices) were assessed at 1, 3, 6, and 12-month follow-up periods. RESULTS: Fifty patients (25 receiving conventional implants-12 females, mean age of 65.3 ± 7.3 years; and 25 receiving mini-implants-11 females, mean age of 66.8 ± 8.1 years) was analyzed. Peak insertion torque (P = .001) and bone loss (P = .02), as well as change in plaque (P = .02) and bleeding (P = .04) indices at 12 months differed significantly between groups. Furthermore, linear regression revealed the height of the locator as a risk factor for bone loss (P = .038). CONCLUSIONS: The present findings suggest that two mini-implants are significantly more susceptible to bone loss after immediate loading, for which the height of locator might be considered a risk factor.

Use of free CAD software for 3D printing individualized face masks based on face scans.

AIM: To describe a method of digitally customizing 3D-printed face mask designs using 3D face scans and free software. MATERIALS AND METHODS: The procedure of creating customized face masks initially involved importing and aligning STL files of face scans and mask components in free CAD software. The imported mask described in this article is composed of three different STL files (body, filter structure, and grid). The body of the mask was then edited to fit precisely into the face scan STL by using the software's offset tool, followed by adjustments and smoothening of the surfaces of the edges. The resulting customized body of the mask plus the filter and grid STL files were exported and 3D printed with polylactic acid (PLA) filament using a fused deposition modeling (FDM) 3D printer. For the purposes of comparison, a conventional 3D-printed mask (from the original STL files, without being customized for the face scan) was also 3D printed from the original STL files. Both face masks were tested on the same two volunteers. RESULTS: The customized 3D-printed face mask presented a higher adaptation compared with the conventional face mask. The area of facial contact matched the one digitally designed in the software. The 3D-printed grid could clip exactly into the filter, which in turn could be precisely screwed into the body of the face mask. CONCLUSION: Within the limitations of this technical report, the present findings suggest that customized 3D-printed face masks with enhanced adaptation can be digitally designed using face scans and free CAD software.