Evaluation of the Color Change of the Laser and Chemical Vital Whitening Method in the Teeth
Condition: Color; Change Teeth, Posteruptive
MeSH terms: Tooth Discoloration
Study type: Interventional

Summary: 
      Having an aesthetic smile has become very common among patients today. Recent studies have
      shown that people aged 18-49 want to have whiter and brighter teeth. The demand for whitening
      has increased by 300% in the last 5 years. New materials and equipment have been developed to
      meet this demand, and various whitening techniques have been developed for use at home and in
      clinical practice. Determination of color in dentistry; It can be divided into two categories
      with the help of visual and computer-aided devices. Eye color determination is the most
      widely used method during the construction of a indirect restoration. The evaluation of tooth
      color by eye is quite subjective. Physiological variables such as external light source,
      experience, age and human eye fatigue, color blindness cause inadequate results. Due to
      interpersonal detection differences during color perception, the lack of standardization in
      the determination of tooth color can be improved with the use of computer-aided devices such
      as spectroradiometer, spectrophotometer, colorimeter and with the help of film-based
      photographs and digital photographs. Spectrophotometric approach; the point of view is
      interesting, as it allows for an objective application, regardless of the practitioner's
      experience. The color selection made with the use of these devices provides a potential
      advantage over the color selection made with the eye. Because these measurements are
      objective, can be counted and can be obtained faster. Although widespread uses of computer
      aided colorimeters and spectrophotometers have been reported in dental studies, most devices
      are not suitable for routine clinical use. Color analysis with these computer-aided devices
      may cause inaccurate results especially in the evaluation of translucent objects such as
      teeth. Therefore, a combination using both eyes and devices should be used.
    

Detailed description: 
      Tooth color; It is formed by the combination of enamel, dentin and pulp with different
      optical properties. Tooth coloring is divided into two as etiological, internal and external.
      External colorants can be removed simply by cleaning. Removal of intrinsic coloring is
      possible with chemical bleaching. In the treatment of tooth coloring, whitening is considered
      the least aggressive method.

      Due to the increasing interest in aesthetics in recent years, patients' demands for teeth
      whitening have increased. Home-bleaching technique, developed by Haywood and Heymann in 1989,
      has been the most frequently used method until recently. In this method, the bleaching agent
      contains 10% hydrogen peroxide. For 2-5 weeks, whitening is performed by placing the gel in a
      plate by the patient every night. The advantages of this method are that it is easy to apply,
      low cost, use of lower rates of hydrogen peroxide, and less time spent in the clinic.
      However, the disadvantages are that the whitening process is not under the control of the
      physician, the patient does not apply the whitening gel regularly, and the procedure takes
      several weeks. Office-bleaching technique has been developed in order to make the bleaching
      process more controlled, to ensure color stability and to shorten the time. This technique,
      which contains a high concentration of (15-38%) hydrogen peroxide, is activated by heat or
      light sources. These sources include plasma arc, LED, UV lamps and laser. However, there is
      no consensus on the effectiveness of heat and light sources used in tooth whitening.

      The light sources used during bleaching are expected to increase the effectiveness of the
      bleaching and shorten the processing time. Among these, plasma arc and diode lasers have a
      wide range of uses. Laser teeth whitening method has been applied for about 15 years and many
      laser devices have been recommended for this procedure. It is expected that the treatment
      time will decrease and the sensitivity that may occur in the teeth will decrease as a result
      of laser application. However, the superiority of laser bleaching compared to other methods
      is still controversial.

      External root resorption and irritation in soft tissues can be observed during the teeth
      whitening, even if in a small amount. It is stated that the sensitivity of teeth after the
      procedure is the most common complication by some researchers, but disappears by itself after
      the end of the bleaching process.

      The purpose of aesthetic applications in dentistry; morphological, optical and biological
      compatibility. Tooth color is one of the most important criteria of aesthetics. Clinically,
      two different methods are used in color selection. The first, visual method, includes
      evaluation with the naked eye. The second method is colorimeter, spectrophotometer etc. is
      the use of devices that measure color. During clinical applications, color selection of
      dental materials is done by using visual scales. Color selection by visual method is both
      subjective and difficult; it can also lead to inadequate results. During color selection,
      erroneous results may occur due to parameters such as ambient light, physician's experience
      and age, and eye fatigue.

      Due to these existing disadvantages, systems such as spectrophotometers, colorimeters,
      digital color meters have been launched to assist the physician in color selection. In
      dentistry, spectrophotometers and colorimeters are used to overcome problems related to color
      selection with the eye. Although the visual method is used more in the selection of colors by
      clinicians, it is stated that the color measurements made by using the visual method and
      spectrophotometer together are quite successful.

      Color is formed by the merge of wavelengths in a light beam. In order for an object to be
      visible, it must emit light or reflect light from a light source. From the point of view of
      dentistry, the property of objects to reflect the incoming light is more important. The
      incoming light usually consists of a mixture of various wavelengths, that is, it has a
      polychromatic feature. When light comes on an object, it absorbs certain wavelengths and
      reflects certain wavelengths. The human eye can distinguish light between wavelengths of
      400-700 nμ. Nerve responses play a big role in the appearance of color. As a result of
      attached stimulation, the eye gets tired and the reaction of the eye decreases. Color
      separation is a subjective issue.

      The first color specification was proposed by CIE in 1931. Although this system was developed
      in the following years, its principles have still not changed. CIE system uses 3 variables,
      X, Y and Z. These variables are based on the spectral response functions defined by the CIE
      observer. The CIE chromaticity diagram is also used to define the exact color. In another CIE
      color system, three variables are used: L *, a * and b *.

      The spectrophotometer is a photometric appliance that is used to measure the transmittance,
      reflection and true absorption of color. They contain prisms or dispersing parts to create a
      continuous color line in their structure. Spectrophotometric color measurements may vary
      depending on the light source used and the measurement mode. Some spectrophotometers can be
      used according to two different measurement modes: Specular Component Included (SCI) and
      Excluded (SCE). Many types of standard light source are also used for color measurement of
      dental materials. These devices give three stimulus values x, y, z or CIE L *, a *, b *.
      These values can be converted into numerical values and color variables of different objects
      can be compared.

      The aim of the study is to compare the color change caused by laser-activated and chemically
      activated vital whitening systems with two different evaluation methods (digital camera and
      spectrophotometer). In this way, a comparison of the effectiveness of both the whitening
      systems and the reliability of the evaluation methods will be made. It is also aimed to
      determine the sensitivity of the teeth that may occur during and after bleaching.
    

Intervention name(s): Laser Bleaching; Chemical Bleaching
Intervention type(s): Procedure; Procedure
Intervention description(s): Content; There are 35% hydrogen peroxide, potassium nitrate, sodium fluoride, sodium hydroxide, thickener, glycol derivative. The way of application; Gingival protection is applied. The gel is applied to the labial surfaces of the teeth with a thickness of 1-2 mm. The use of laser increases the effectiveness of the gel. Operator and patient use protective glasses during laser application. The gel shows its effectiveness in about eight minutes. Then the gel is removed with the help of saliva absorber. The procedure is repeated until the desired degree of whitening is achieved. Then it is checked with a color scale.; "Total Blanc Office Teeth Whitening System (H35)" will be used as chemical whitening agent. Content; There are 35% hydrogen peroxide, thickener, plant extracts, amide, release agent, glycol, paint and water. Method of Application; Gingival protection is applied. A 1 mm thick layer of gel is applied to all of the labial surfaces of the tooth. The whitening agent remains on the tooth surface for 20 minutes. At the end of this period, the gel is removed with saliva absorber and the surface is cleaned with a moist gauze.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Investigator)
Primary purpose: Other
Keywords: Vital Bleaching; Color measurement; spectrophotometer