Articles from Style ItalianoPolishing lifelike composite2011-11-19 13:11:37 admin

An Article by…

Dr Jordi Manauta

Submited:

13/02/2012

This article is part of chapter 10 of the book “layers” by Dr. Jordi Manauta and Dr.Anna Salat which will be published by Quintessence books on september 2012

The aim of this step-by-step article is to show how easy is to obtain extremely shinycomposite restorations, with rich morphology and long lasting surface stabilitychanging just 3 times the bur in our contrangle.

Fig1.- the tree rotating instrumentsused, from lef to right goat brush (Shiny S, Micerium, Italy), felt wheel (Shiny F,Micerium, Italy) and Periocare blue ring bur (DC Pericare 831 524 014, AlicanteSpain)

Fig 2.- A sample tooth of white composite (Intensivemilk “IM”, Micerium) obtaining on purpose a terrible surface after final polymerization.The color white is to obtain full visibility in this exercise.

Fig 3.- Probably the most important step is the first ofthem. We place in the contrangle @10,000rpm (maximum) the Periocare blue ringbur and obtain a smooth surface, trying to eliminate all the excesses andirregularities to obtain a continuous surface. The aim is to educate ourselves toachieve a “biscuit try” like surface which any ceramist can teach us very precisely.This step usually is where we focus most of the time in the finishing and polishingstage.

Fig 4.- with a sharp pencil we mark the proximalangles to define the shape of the tooth (primary anatomy).

Fig 5.- Following the marked lines, always with thesame bur, we do some pre-interproximal grinding at low speed. This step can bedone in a clinical case and often we must get help with red and yellow diamondpolishing strips (intensiv). Note how the tooth changes its shape dramatically.

Fig 6.- With the pencil we can mark the path to dosome incisal characterizations (if needed) in this case we make the proximal lobesmore short as in many young teeth.

Fig 7.- after incisal grinding (with the same bur) wemark some incisal lobes division and develop them with the tip of the bur. If theyneed to be really sharp we can help ourselves with the red diamond strip.

Fig 8.- In order to develop secondary anatomy (macrotexture), we mark some vestibular weaves which must be sharper in the cervicaland wider in the incisal, but always very smooth, we shall never see the “bur shape”marked on our restorations. To achieve this we must pass the bur from mesial todistal, applying more pressure when approaching the center of the groove andreleasing int he surroundings.

Fig 9.- With a pencil we mark the tertiary anatomy(micro texture), note that the more close and parallel the grooves are, the morenatural they look.

Fig 10.- With the same bur always at low speed, wecan develop with just the tip, each one of these grooves. the more pressure wemake, the deeper the grooves will be.

Fig 11.- after the finishing stage with the bur (which Iconsider to be the most important) the we start the polishing and shinnig, to do thiswe switch to the goat brush and apply a 3 micron diamond paste (Shiny A,Micerium, Italy), we spread the paste with the brush without rotation, then we start@3,000 rpm with no water, doing really slight touches otherwise extreme heatingcan happen and ruin something more than the restoration, and then @15,000 rpmwith water.

fig 12.- we repeat exactly the same steps but this timewith a 1 micron diamond paste (shiny B, Micerium, Italy)

Fig 13.- For the high gloss polishing, we switch to thefelt wheel and apply a 1 micron aluminum oxide paste, repeating the spreading,3,000 rpm with no water and 15,000 rpm with water.

fig 14.- The restoration showing a “ceramic like”appearance, after cleaning with a gauze the paste excess.

Fig 15.- The tooth observed from a 45º degree view,shows strongly the surface characterizations and secondary and tertiary anatomyplaying a fundamental role in lifelike of restorations.

Fig 16.- When working extraorally we can use somesilver powder to study shape, texture and every minimum detail of our work.