Bio-mechanics

For a general understanding of v-bend placement and loop comprehension, please look for the articles of the Professor of the Orthodontists you have mentioned: Dr. Charles J. Burstone. I'd recommend you to try to stay away from recipes for use of mechanical appliances of people that usually work for companies, not for Orthodontics. That won't help you very much in your understanding of biomechanics and will probably only increase your confusion.

A few comments:
1) If you want to have a more precise idea about the force system involved during space closure, you have to try segmented arch mechanics. If you use continuous arches it is too difficult to measure or predict the force system. There are studies showing force systems for segmented arches. A lot of people recommend a few methods for continuous arches but you will have to "believe them" and sometimes not in physics, since estimation of the force system for v bends in continuous arches is pretty difficult. Mulligan's method for cuspid retraction is effective if you do not bond brackets on the bicuspids. You need that interbracket distance. For evidence-based placement of v-bends for incisor retraction, it is more complicated because the arch has 3 dimensions and the classic article on v-bend placement can be applied correctly only to a straight wire. A student from Dr.Lindauer from Virginia Commonwealth University completed his thesis on this type of v-bend placement. I think the result is shown in one of the editions of Seminars in Orthodontics. V-bends placed on continuous arches tend to deformate the anterior part of the arch affecting second-order positioning. Take a look.

2) If you want to talk about T-loops for example, generally there are two methods for placement of V-bends. The first, simpler, is to use the v-bend incorporated on the loop itself (see the last Kuhlberg & Burstone article from 97 or the book Modern Edgewise Mechanics and the Seg. Arch Technique).

If you use this method, you position the loop asymmetrically in direction of the unit you want to keep stable (2-3 mm of asymmetry). I use this method when I start with a symmetrical loop and need more control in the end of space closure, when I reactivate the loop. The second method is to use the natural activation moment of the loop (that would configure a v-bend) together with a v-bend placed away from the loop. So you have a dynamic truncated v-bend as a result during space closure. In this method, you use a curved or acute v-bend near the unit you want to keep stable and the loop positioned near the active unit. This method is better if you want to control the anchorage since the beginning. For the rationale of the choice, wait for my article on this matter in the AJODO, which is on the Journal's line for publication, named "Self-corrective T-loop design for differential space closure".

After segmented arch space closure and root movement if necessary finishing can be performed with continuous arches.

Courtesy: Rodrigo F. Viecilli, CD, Ortho. Cert. (Brazil) - The Electronic Study Club of Orthodontics