Protapers are a modern version of nickel-titanium instruments that are actively used during root canal preparation. They are super flexible, so they work in areas that are difficult to access for traditional tooling. Consider the structural features of manual protapers, their advantages and disadvantages, as well as the application.
Advantages of working with universal protapers
Proteipers are made of a special alloy, which is 56% nickel and 44% titanium. They have the same design as the machine variants, but are used in more complex clinical situations. Due to their superflexibility, high safety and cutting efficiency, they are widely used by dentists in clinics.
Advantages of manual protapers:
Thanks to the color coding, it is easy to select the sequence of instruments, regardless of the shape of the root canal. Means for drying and obturation have the same color scheme.
To work, you need only three tools that have high cutting efficiency.
Processing of the root canal and removal of the dentine sawdust occurs qualitatively due to the increased conicity of the apical part.
The probability of deviating from the passage of the channel is minimal due to the rounded guide tip.
Most dentists prefer the manual option due to the better tactile control during complex manipulations from the anatomical point of view.
Work with manual protapers: classification
Dental protapers for endoscopic treatment are used strictly according to the instructions. Each set contains six tools that can be divided into two groups: forming and finishing files.
Forming files are designed to give the root canal a specific shape.
Varieties of forming files:
- SX - are used to work with short root canals or to give the necessary shape to the crown part of long passages (protector length is 19 mm, diameter at the tip of the working part is 0.19 mm, base circumference is 1.20 mm).
- S1 - used to prepare the upper third of the root canal (the size of the manual protector can be 21 or 25 mm, the diameter at the tip is 0.17 mm, the taper increases along the entire length of the working part from 0.02 mm to 0.11 mm)
- S2 - the length is equal to the previous version, but was created for the preparation of the middle third of the root canal (the circumference at the tip is 0.2 mm, the taper increases gradually from 0.04 mm to 0.115 mm).
Finishing files are used at the final stage to design the apical third, alignment and expansion of the middle third of the channels. They are divided into the following categories: F1, F2 and F3. All have a fixed taper, quite flexible, but differ in length. Size F1 is 0.2 mm, F2 is 0.25 mm and F3 is 0.3 mm.
It is possible to use auxiliary forming files (shapers), which are used to optimize short channels, to access long passages or to determine a directional channel.
Marking Hand Tools
Manual ProTaper is used for the same manipulations as the machine one, but in more complex cases. Moreover, the marking on the products is the same. The standard set consists of six tools, which are distinguishable by the color of the handle depending on the technical data.
Standard marking of handles of assorted manual protapers:
- Sx - orange;
- S1 is purple;
- S2 - white;
- F1 - yellow;
- F2 - red;
- F3 is blue.
Thanks to these notations, it is convenient to use hand tools in the required order. There are also F4 (with a black handle) and F5 (with black and yellow), the length of the active region of which is 22 mm. They are intended for starting or final processing of root canals.
Design features
Knowing the features of the work and the order of manual protapers, it is worth noting their structural characteristics. It is thanks to them that the work of the dentist in hard-to-reach places is greatly facilitated.
A design feature that provides the benefits of work is as follows:
Improves flexibility, efficiency when cutting, so there is no need to re-pass through the channel. For example, the Sx file in the interval D1-D9 has a progressive taper of 3.5% to 9% and a fixed taper of 2% in the interval D10-D14. Also, nine values have the file S2, and S1 - 12.
- The trihedral cross section is convex.
Thanks to this, the main shaft is strengthened, and the tool itself becomes super flexible. This also significantly increases safety, since the torsion load is reduced, and the likelihood of contact between the channel walls and the tool blade is minimal.
- Spiral steps and angles vary.
The angle of the spiral and the pitch is constantly changing, making it easier and more efficient to extract waste material.
- The tip diameter differs depending on the file.
Files, both finishing and forming, have different diameters for safe and effective advancement deep into the channel.
Due to the shape of the tip, the use of the tool does not damage the walls of the channel, penetrating through soft tissue.
The size of the handles is up to 12.5 mm, which improves access to the chewing teeth.
It allows you to dissect channels of any complexity, making hand tools universal.
Indications and contraindications for use
The work of manual protectors according to the method is so subtle and delicate that the devices are used only in the conditions of a medical institution by specialists who have undergone special training. Tools are designed to form and clean root canals. Thanks to their super-flexibility, the channel is easier to clean.
Their introduction is carried out by light pressure, which ensures the patency of the zone. But at the same time it is necessary to observe the speed limit in the range of 500-700 rpm. There are no contraindications to the use of hand tools.
Disadvantages of working with protapers
Despite the large number of work advantages, manual protapers also have disadvantages.
The cons include:
- the inability to process wide channels (more than 30 sizes), since there is no tool with a large apical diameter;
- the maximum length of the channel that can be processed reaches 31 mm;
- a mechanism to prevent obturation is not provided, a layer of lubricant may remain on the walls of the canal, which will subsequently prevent medication from entering the canal.
Precautionary measures
Using hand tools, you should adhere to certain rules.
Precautions are as follows:
- many tools are marked for “one-time use” (sterilizing and disinfecting reusable increase the risk of file fracture);
- protapers are not immersed in sodium hypochlorite solution, the concentration of which exceeds 5%;
- cleaning is carried out strictly according to the instructions;
- manual protapers are used at a constant speed in the range of 150-350 rpm .;
- the file is checked for possible deformation, cleaning the grooves should be carried out as often as possible;
- to create straightforward access to the channel, it is worth using the forming files with separate sweeping movements;
- sweeping movements are not applied to the finish files;
- using the finish files for the entire working length, you should immediately remove the tool.
Root canal machining technique
Processing channels using hand tools is carried out in different ways, which directly affects the use of manual protapers in order.
Varieties of processing techniques:
Hand-held endotonic instruments are used starting from the smallest size. As you move along the channel, larger diameter protapers are used, reaching all the lengths of the passage. Processing takes place with one large K-file. After it is fully inserted into the channel, the tool rotates 90 degrees clockwise in depth.
The reverse rotation occurs with a slight pressure counterclockwise at 270 degrees. Then follows another turn in the opposite direction of 180 degrees. After that, the instrument is removed from the mouth, processed by medicines and re-introduced into the canal for the entire length.
First, you need to expand the root canal to the apical opening, after which the K-file is introduced one size larger, but 1 mm less than the working length. After that, the tool is changed, in which the working length gradually changes (by 2, 3 mm and so on). With the help of H-files, the root surface is smoothed, and thus its conicity is formed.
The formation of the mouth middle part and access to the apical third of the canal is carried out after the expansion of the mouth. Next, the working length and tooling are determined. The walls of the channel are aligned in the final part.
General recommendations
According to the technique, manual protapers are disinfected, cleaned and sterilized before use (18 minutes using an autoclave and at a temperature of 134 degrees, pressure not more than 3 bar).
General provisions include the following:
- Disposable tools are not reusable.
- The sterility of the product is the responsibility of the doctor who uses the instrument.
- To avoid contamination, it is worth using personal protective equipment (glasses and gloves).
- Disinfectant solutions must be of high quality.
- Hydrogen peroxide destroys tungsten carbide burs, nickel-titanium tools and plastic coasters.
- Do not use caustic soda solutions, alkali and mercury salts.
- The maximum amount of machining of hand tools is limited to five. After that, they begin to collapse.
Output
Manual protapers, according to dentists, are much easier to use than machine ones. They are convenient and help in difficult situations with non-standard anatomical features of the root canal. At the same time, using such tools is strictly according to the instructions. It includes not only the rules of use, but also safety measures. In general, hand tools have many more advantages, so they are often used.