Causes of Implant Failure and Subsequent Removal: A Retrospective Study in a Hospital setting.

Despite high rates of success for dental implants, implant failure due to several causes may require explantation. In the present retrospective study, implants removed between 2000 and 2022 have been registered and the cause of removal has been established. All implants were removed by a single operator (PPM) in the department of Oral Surgery of the George Eastman Dental Hospital in Rome, Italy. Characteristics of removed implants such as implant surface, morphology (bone versus tissue level implants), type of restoration (fixed versus removable), in the case of fixed restorations, mode of retention (cement versus screw-retained), location of the implant (maxillary versus mandibular arch) were recorded. Furthermore, patient-level characteristics were also recorded (systemic health conditions and medications taken, smoking habits and previous history of periodontitis). In total, 381 implants in 381 patients were removed in the 20-year time-span. The most frequent cause of removal was peri-implantitis (82.4% of implants), followed by implant malposition and loss of osteointegration. The survival time was not affected by the cause of removal, while bone level implants had a longer survival time versus tissue level implants. Maxillary implants had a higher prevalence of peri-implantitis compared to mandibular implants.

Electroretinogram B-wave amplitude in panic disorder.

Abnormal light-related behaviors have been described for patients with panic disorder (PD). The present study was undertaken to investigate the retinal light response in PD using electroretinography (ERG). The authors conducted b-wave ERG measurements with a bright light (after dark adaptation) in 28 patients with PD and 28 control subjects. There were no significant differences in the mean b-wave amplitude between the two groups, but the retinal response to light in PD patients was generally lower than in healthy subjects. A large interindividual variability was found; also noted was a significant difference in the mean b-wave amplitude between the right and left eyes in the control group. The data indicate subtle variation of retinal photosensitivity in a subgroup of patients with PD. Because dopaminergic retinal activity affects b-ERG amplitude, the authors hypothesize that the dopaminergic system is involved in the response to light in PD patients.