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Objective: The objective of this study is to investigate the association of peri‐implantitis (PI) and sinus membrane thickening and to assess the resolution of membrane thickening following intervention (implant removal or peri‐implantitis treatment) aimed at arresting PI. Materials and Methods: Forty‐five patients with 61 implants in the posterior maxillary region were retrospectively included in the study. Twenty‐four patients were diagnosed with peri‐implantitis (PI) and 21 had peri‐implant health (PH). Cone‐beam computed tomography (CBCT) scans were evaluated to assess maxillary sinus characteristics, including membrane thickening, sinus occupancy and ostium patency. The CBCT scans taken 6 months after intervention aimed at arresting disease (implant removal or treatment of PI) in the PI group were also appraised and compared to baseline scans. Results: At baseline, all parameters evaluating membrane thickness disorders yielded significant differences between groups (p <.001). Patients with posterior maxillary implants diagnosed with PI were 7× more likely to present membrane thickening compatible with pathology when compared to patients with healthy implants (OR = 7.14; p =.005). Furthermore, the likelihood was 6x greater in implants diagnosed with PI to exhibit moderate membrane thickening (OR = 6.75, p =.001). The patients receiving interventions aimed at arresting PI experienced significant enhancement in all radiographic parameters related to the sinus cavity at the 6‐month follow‐up (p <.001), though these variations were similarly independent of whether treatment consisted of PI treatment or implant removal. Conclusions: Maxillary sinus membrane thickening and the permeability/obstruction of the ostium are frequently associated with the presence of PI in posterior implants. Interventions targeting disease resolution effectively reduce membrane thickness to levels compatible with maxillary sinus health. [ABSTRACT FROM AUTHOR]

Objectives: To radiographically evaluate the stability of the bone substitute augmented outside the buccal bony arch contour in the maxillary esthetic zone. Materials and Methods: Patients who missed a single anterior tooth and received simultaneous GBR in implant surgery were included. The contralateral homonymous area of the implant site was horizontally mirrored as the individual bone arch contour. According to the relative position of the postoperative buccal grafts and bone arch contour at the implant shoulder, 62 patients were allocated into the outside‐contour (OC) and inside‐contour (IC) groups. Cone‐beam computed tomography was performed before surgery, after implant insertion, before re‐entry surgery, and at follow‐up. The profilometric changes of the buccal bone plate were analyzed via the bone distance to the mirrored bony contour. Results: At the implant shoulder, the bone distance in the OC group was higher than that in the IC group, with statistically significant differences at re‐entry surgery and follow‐up. However, the bone grafts outside the bone arch contour were reduced into the contour after remodeling and showed more bone resorption than the IC group. At other vertical levels below the implant shoulder, bony grafting of overcontour 1–2 mm range was favorable to regenerate stable bone plates reaching the individual contour at follow‐up. Conclusions: The overaugmented bone outside the buccal bone arch contour tended to remodel into the original contour, which indicates that the anterior bone arch contour is worthy of careful observation for deciding buccolingual implant position and bone augmentation width. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the influence of metal artefact reduction (MAR) in the diagnosis of dental implant contact with the mandibular canal (MC) using cone beam computed tomography (CBCT). Methods: Dental implants were installed with surgical guides in the posterior hemiarches of 10 dry human mandibles: 0.5 mm above to the MC cortex (G1/n = 8) and 0.5 mm inside the MC (G2/n = 10). The experimental set‐up was scanned with two CBCT equipment using 85 kV and 90 kV, MAR ON or OFF, and different tube currents (4 mA, 8 mA and 10 mA). Two dentomaxillofacial radiologists (DMFRs) and two dentists (DDS) scored the relation between the dental implant and MC. Descriptive statistics were used to observe the absolute frequency of scores. Sensitivity, specificity and accuracy were calculated considering the known relation between the dental implant and the MC interior. McNemar's test (α =.05) was applied to compare the diagnostic efficacy of MAR ON versus MAR OFF. Results: Overall specificity was higher than sensitivity for both DDS and DMFR (97% vs. 50% and 92.0% vs. 78.0% respectively). There was a significant effect of MAR (p =.031) for DMFR in the case of contact between the dental implant with the MC interior, in which sensitivity decreased with MAR activation from 90% to 40%. DMFR observers showed a better diagnostic performance compared with the DDS observers (accuracy of 84.0% and 71.0%, respectively). Conclusions: Due to the limited efficacy of MAR, it should not be used when conducting CBCT scans for the evaluation of contact between the implant and the mandibular canal. [ABSTRACT FROM AUTHOR]

Aim: To assess, in vitro, variables potentially influencing implant blooming using a human‐like imaging phantom and 3D‐printed mandibles. Material and Methods: Sixty implants were inserted in 3D‐printed mandibles in 26 different configurations in order to examine the impact of implant diameter, presence of a cover screw, implant design/material, implant position, and the presence of additional implants on implant blooming using two cone‐beam computed tomography (CBCT) devices (Accuitomo [ACC] and NewTom [NWT]). Two observers measured the amount of implant blooming in both buccolingual and mesiodistal directions. Inter‐rater agreement and descriptive statistics, grouped by implant characteristic and CBCT device, were calculated. Results: Both CBCT devices increased implant diameter (a mean increase of 9.2% and 11.8% for titanium, 20.3% and 24.4% for zirconium, for ACC and NWT, respectively). An increase in implant diameter did not increase the amount of blooming, whereas placing a cover screw did (from 8.0% to 10.9% for ACC, and from 10.0% to 15.6% for NWT). Moreover, implant design, anatomical region, and the presence of another implant also affected the extent of the blooming. Conclusions: Dental implants show a clear diameter increase on CBCT, with the effect being more pronounced for zirconium than for titanium implants. Similar effects are likely to occur in the clinical setting, potentially masking nonosseointegration, reducing the dimensions of peri‐implant defects, and/or causing underestimation of the buccal bone thickness. [ABSTRACT FROM AUTHOR]