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Aim: Temporary anchorage devices (TADs) have become the preferred method of skeletal anchorage in new-age orthodontics. Despite the remarkable success of mini implants in orthodontic treatment results, mini implants' stability remains a vital issue that has to be resolved, due to the fact that failure rates are broadly variable and might be up to 25%. Objectives: To evaluate the effect of the diameter, implant bone surface contact, thickness of cortical bone, and implant insertion sites on mini implant stability using resonance frequency analysis (RFA). Materials and Method: CBCT of the dry skull was obtained. Buccal and lingual cortical plates of the maxillary and mandibular jaws were measured at 6 mm from the coronal part of the alveolar bone. After placing the implants, the stability was measured using resonance frequency analysis. Results: In the maxillary arch, Pearson correlation showed significant correlation of instability of the implant with the width of the buccal cortical plate and lingual cortical plate and implant contact surface area. In mandibular arch, Pearson correlation showed no significant effect of buccal/lingual cortical plate width, and implant surface contact area in primary stability of varied sized, mini implants. Conclusion: Statistically significant increases in the primary stability of mini implants with an increase in the implant bone contact surface area were found in the maxilla. In the mandible, no significant increase in mini implant stability was found with an increase in the implant contact surface area. [ABSTRACT FROM AUTHOR]

This article provides a conceptual framework for understanding industrial crises. These crises are organizationally-based disasters which cause extensive damage and social disruption, involve multiple stakeholders, and unfold through complex technological, organizational and social processes. The characteristics of industrial crises are illustrated through a comparison of three diverse crises - the Bhopal disaster, the Tylenol poisonings, and the explosion of the space shuttle Challenger. Relationships among these characteristics are presented in a model of industrial crisis. Some issues for further research are identified. (Reprinted by permission of the publisher.)

Aim: The aim of the study was to evaluate and compare static and kinetic friction of round (0.018") and rectangular (0.019 × 0.025") stainless steel (SS) wires of different brands with conventional preadjusted edgewise brackets., Materials and Methods: Maxillary canine and two bicuspids of 0.022 × 0.028" slot sized MBT prescription (Gemini, 3M Unitek, Monrovia, California) brackets were chosen. The wires selected were 0.018" SS (3M Unitek); 0.018" Australian wire (AJ Wilcock, UK), and 0.019 × 0.025" SS (3M Unitek). The testing was done on Instron 3382. A total of 30 test combinations with three wires were repeated 10 times. The static and kinetic friction was recorded in Newton. The kinetic friction was also recorded in Newton at 3, 5, 7, and 9 mm of movement. One-way analysis of variance (ANOVA) and descriptive statistics were used for comparing the friction. To test the level of significance, multiple comparisons were used within wire in bracket by using post hoc test., Results: Static friction was found to be greater than kinetic in all wires; 0.018" SS (3M) wire exhibited minimum static and kinetic friction; while 0.019 × 0.025" SS (3M) exhibited maximum static friction. Kinetic friction was similar in both 0.018" AJ Wilcock and 0.019 × 0.025" SS but greater than 0.018" SS (3M)., Conclusion: Least static and kinetic friction was exhibited by 0.018" SS (3M). Kinetic friction was similar in both 0.018" AJ Wilcock and 0.019 × 0.025" SS., Clinical Significance: The study concluded that 0.018" SS (3M) is better for individual canine retraction than the other wires used in the study because it has the least frictional resistance; 0.019 × 0.025" SS (3M) is a better wire for canine retraction than 0.018" AJ Wilcock as we can have a three-dimensional control over tooth movement. When torque control is not a prime requisite, then 0.018" SS (3M) can be used for retraction of incisors instead of 0.018" AJ Wilcock in severely proclined incisor cases.