Sutures maintain the position of the flap reattachment during the initial phase of the first-intention healing process. A suture should just compensate for the tension of the flap. It should be atraumatic, non-allergenic, and easy to use.
Outside the retrocavity, the area should be covered by cotton pellets in order to prevent MTA excess from falling out.
A 1:2 powder/liquid ratio is mixed to putty consistency. Pieces of MTA can be delivered by using Lee's rule, syringes, or plastic sleeve.
Amalgam
Amalgam has been used for a long time, but it has several problems. There tends to be marginal adaptation and filtration. There is also a problem with biocompatibly. In subcutaneous and bone studies, amalgam was cytotoxic due to free mercury ion release (less cytotoxic when set). Amalgams with a higher content of copper or zinc were also cytotoxic due to ion release. In addition, a galvanic current is produced due to contact with metal posts and crowns. Finally, tatoos arise due to corrosion of amalgam/silver cones or leaving amalgam outside the cavity or removal of previous apico-ectomies with amalgam/old silver cones.
A biocompatible material is used to produce a hermetic seal that can prevent the percolation of bacteria or their products between the
root canal system and periradicular tissues.
First-generation microtips were introduced in early 1990 by Cary Carr, made with stainless steel. Second- and third-generations improved the cutting efficiency by reducing the heat produced and the time required to prepare the retrocavity, by covering the tip with an aggressive coating: diamond or zirconium oxide. The more aggressive the tip, the more smear layer is produced.
The aim Is to create a clean and well conformed type 1 cavity into the already sectioned root. It must have walls that are parallel to the major axis and well centered into the root, in order not to weaken the root walls; and deep enough to retain the biocompatible material of obturation. The retrocavity should have 3 mm depth when a previous retreatment has been done: the "Rule of Threes”.
One percent methylene blue applied with a microbrush is used on the dried resected root for 10-15 seconds before washing and drying60. Saline is used to wash away excess. The microscope is used at maximum magnification (16-25x). Methylene blue tints collagen fibers, so it is used for:
Many topical hemostatic agents are available (as listed above under ?Armamentariumâ), with differences in origin, action, ability to control bleeding, and effect on healing. No one topical hemostatic agent is ideal; each has disadvantages.
Hemostasis is an indispensable factor for microsurgery because a dried surgical field provides better visualization of the microanatomy, dramatically improves the surgical efficiency and minimizes root-end filling contamination.
The aim is to remove pathological tissues, foreign bodies and bone particles from the periradicular or lateroradicular areas. Curettage provides visibility and accessibility to the apex or lateral canal.
The 5 mm osteotomy window is big enough to remove a huge amount of granulation tissue in one piece, especially when there is a capsule-like structure. The microscope is used at medium magnification (10-16x)24.