Accommodating exogenous variable and decision rule heterogeneity in discrete choice models: Application to bicyclist route choice.

The proposed research contributes to our understanding of incorporating heterogeneity in discrete choice models with respect to exogenous variables and decision rules. Specifically, the proposed latent segmentation based mixed models segment population to different classes with their own decision rules while also incorporating unobserved heterogeneity within the segment level models. In our analysis, we choose to consider both random utility and random regret theories. Further, instead of assuming the number of segments (as 2), we conduct an exhaustive exploration with multiple segments across the two decision rules. The model estimation is conducted using a stated preference data from 695 commuter cyclists compiled through a web-based survey. The probabilistic allocation of respondents to different segments indicates that female commuter cyclists are more utility oriented; however, the majority of the commuter cyclist's choice pattern is consistent with regret minimization mechanism. Overall, cyclists' route choice decisions are influenced by roadway attributes, cycling infrastructure availability, pollution exposure, and travel time. The analysis approach also allows us to investigate time based trade-offs across cyclists belonging to different classes. Interestingly, we observe that the trade-off values in regret and utility based segments for roadway attributes are similar in magnitude; but the values differ greatly for cycling infrastructure and pollution exposure attributes, particularly for maximum exposure levels.

A Nonconventional Approach to Formocresol Pulpotomy.

A different concept of formocresol pulpotomy procedure has been proposed where the formocresol pulpotomy is done with smaller access to the pulp chamber. In our study formocresol pulpotomy was carried out in 128 primary molar teeth with a limited amount of access opening, saving a bit of more tooth structure, which excludes the requirement of placement of a stainless steel crown (SSC). In 2 years follow-up period, no crown fracture was reported. One hundred fifteen teeth remain vital at the end of 2 years period of observation with the periodic clinical and radiographic review. The result shows 89.4% clinical and radiographic success of this nonconventional pulpotomy procedure that corroborates with several studies of the conventional formocresol pulpotomy procedure. HOW TO CITE THIS ARTICLE: Chakraborty A, Dey B, Jana S. A Nonconventional Approach to Formocresol Pulpotomy. Int J Clin Pediatr Dent, 2018;11(6):490-495.

Healing of apical rarefaction of three nonvital open apex anterior teeth using a white portland cement apical plug.

The major challenge of performing root canal treatment in an open apex pulp-less tooth is to obtain a good apical seal. MTA has been successfully used to achieve a good apical seal, wherein the root canal obturation can be done immediately. MTA and White Portland Cement has been shown similarity in their physical, chemical and biological properties and has also shown similar outcome when used in animal studies and human trials. In our study, open apex of three non vital upper central incisors has been plugged using modified white Portland cement. 3 to 6 months follow up revealed absence of clinical symptoms and disappearance of peri-apical rarefactions. The positive clinical outcome may encourage the future use of white Portland cement as an apical plug material in case of non vital open apex tooth as much cheaper substitute of MTA.