Niigata Chuoh Junior College

Background Abutment screw-fractures are becoming more frequent complications as implants grow in popularity. The clinicians have been attempting to retrieve the fractured abutment screws without damaging. Comparing a popular method for screw retrieval to the repair service set may elucidate the course of action when encountering fractured abutment screws in a clinical setting. Also, a clinical assessment is to verify the completeness of removal of the fractured screw is still missing in the literature. Aim/Hypothesis The aim of this study was to compare the success rate of two methods for retrieving the fractured abutment screws from inside the implant body by three assessments. Moreover, the damages to the abutment implant interface were observed by three techniques. Material and Methods Twelve models were prepared for the assessment. Each model included four implants at canine and second premolar sites. 48 out of 24 were prepared for testing retrieval of fractured abutment screws out of implant bodies. The methods for the retrieval of fractured abutment screws were classified into two groups. Group A consisted of dental excavator (n = 12) and group B comprised the repair service set (n = 12). Twelve dental clinicians were asked to remove the fractured abutment screw. The time required for removal was recorded in each group. The outcomes were screw satisfactory removal (yes no) and required time (minutes). The completeness of the removal of any abutment screw material was measured by the fit of an impression post, a dental surgery microscope, the use of elastomeric impression material. These clinical assessments were compared to readings from a stereomicroscope evaluation. The outcomes were sensitivity and specificity. All analyses were performed using SPSS 24. Results After the participants attempted to remove the fractured abutment screw in group A, 58.3 percent of the samples were considered satisfactorily removed by the four assessments, whereas in group B, 100 percent, 83.3 percent, 66.7 percent and 75 percent of fractured screws were considered successful in the impression post, dental surgery microscope, silicone replica and stereomicroscope evaluations, respectively. Neither success nor time to fractured screw retrieval showed statistical differences between both groups. Group A presented no damage to the interior implant threads, and small damage was observed above the interior implant screw hole, whereas in group B, the damage was observed to the initial two threads. Conclusions and Clinical Implications For the retrieval of fractured screws, no significant difference was found. Therefore, the dental excavator may be the first option to retrieve fractured screws. When using the repair service set, the silicone replica technique may be used to assess the completeness of removal of the screw. If fractured screw fragments remain, the service set should be reused correctly, and perhaps an ultrasonic scaler could be used to help retrieve the apical portion of the fractured abutment screw.

ABSTRACTJustice orientation is a justice-relevant personality trait, which is referred to as the tendency to attend to fairness issues and to internalize justice as a moral virtue. This study examined the moderating role of justice orientation in the relationship between justice perception and response to a decision problem. The authors manipulated procedural justice and the outcome valence of the decision frame within a vignette, and measured justice orientation of 174 Japanese participants. As hypothesized, the results indicated an interaction between procedural justice and framing manipulation, which was moderated by individual differences in justice orientation. In negative framing, justice effects were larger for individuals with high rather than low justice orientation. The results are explained from a social justice perspective, and the contributions and limitations of this study are also discussed with respect to our sample and framing manipulation.

The purpose of this study was to examine whether the auditory image of a pure tone facilitates or interferes with the auditory perception of the pure tone. The masked threshold of a pure tone in white noise with and without the image of a pure tone was compared. It was shown that, in contrast to Farah and Smith's (1983) finding of facilitation, imagery interfered with the detection of the pure tone only when the frequency of the imagined tone and the detected tone was the same. This interference was interpreted as showing the assimilation of the signal tone into imagery, i.e., the effect described by Perky in 1910, occurred in the auditory modality. An explanation of the differences between findings of interference and facilitation is offered.