When we use the word dose in the DMC manual, you’ll notice that the word “energy” will be in parentheses. The dose we refer to is the amount of Joules (energy) deposited in the tissue. For example, we use between 0.5 and 2 Joules for soft tissue healing processes.
Creep, in turn, is the amount of energy deposited in a given area, which by convention is the area of ​​the cross-section of the laser beam when we apply it in a timely manner. In the example cited above, the creep would be between 15 and 50 J/cm².
When we want to use laser therapy as a function of the patient’s characteristics, we need to reduce the dose or the fluency, because both parameters are interconnected. Decreasing the dose will automatically decrease the fluency. Similarly, the irradiation time will be decreased in the same proportion.
For ease of use and taking into account that the most prominent display on the equipment display is dose (J), you can use this parameter to adjust to the patient.

Low-level laser paresthesia treatment has the following objectives:

1. Accelerate nerve regeneration;
2. Stimulate contralateral innervation by causing adjacent nerves to play the role of the severed nerve;
3. Biomodulate the nerve response by bringing the action potential threshold to normal.

Since neuropathy exists, ie nerve cells tend to get used to certain stimuli, the treatment recommended by Nupen is to apply the dosage gradually. Initially we used a low dosage (1 to 2 J) per point in the first three sessions; in the next three sessions we use 2 to 3 J per point and in the other three sessions 3 to 4 J (1 J increases every 3 sessions). The decision to use the minimum or maximum doses described will depend on the time of the paresthesia (most recent intermediate doses, immunosuppressed patients, the elderly and children we use the lowest doses and the highest dosages we use for most patients, normal adults.
To calculate the application time just select on your equipment the dosage to be used in J, it will give you the application time punctual. It is important to remember that we use the spot irradiation mode by touching the equipment to the target tissue. In addition, it is important to take note of the patient’s improvement, asking each patient the percentage of improvement and different sensations experienced such as needling, tingling and even pain. In the latter case it is recommended to decrease the dosage. The first two reported symptoms usually indicate positive evolution. The frequency of application may be every 48 hours (fastest results), every 72 hours or once a week, depending on your patient’s availability.

Herpetic lesions have 3 distinct stages of manifestation and we must identify them clinically before using laser therapy correctly. The following is a description of the 3 phases and the recommended dosimetry.

– Prodromal Phase: Itching, heat and redness in the region. The manifestation is observed in the face of hormonal variations (menstrual phase), situations of stress, emotional shaking, low immune resistance (colds for example) and excessive exposure to the sun.
DOSIMETRY: infrared laser with the dose of 3 J at 2 or 3 points in the region.

– Vesicle Phase (small vesicles, pain and swelling in the region): In this phase the herpes virus can be transmitted by direct contact with the vesicular fluid. Self-contamination in other parts of the body should be avoided, using towels and individual dishes until the end of this phase.
DOSIMETRY: Almeida-Lopes technique of drainage through laser irradiation over the lymphatic chain responsible for the affected region and around the lesion. The laser used is infrared with the dose of 3 J.

– Lesion healing phase (crust phase): In this phase the patient no longer reports pain, but uncomfortable with the wound that takes a long time to heal completely.
DOSIMETRY: Red laser dose of 1 J, 2 J or 3 J points on the lesion depending on the extent of the lesion, daily until complete healing.

Laser therapy in dentin hypersensitivity acts in two ways:
1. Promoting immediate analgesia, reported by the patient immediately after application;
2. Stimulating the formation of reparative dentin in the medium and long term.

Before starting laser therapy it is recommended to check the cause of hypersensitivity. Among the most common are: root scraping, tenderness after routine occlusal adjustment, exposure of dentinal tubules and cutting of odontoblastic extensions after a cavity preparation, gingival retraction (due to excessive brushing force, bruxism, excessive acid feeding, etc.), among others. .

Protocol for immediate analgesia: Application should always be with the laser tip perpendicular to the tooth or apical region. Infrared laser at doses of 3 J is preferably used when a single application is chosen as a treatment, for example in post-whitening hypersensitivity. According to the patient the clinician may choose one of the therapeutic modalities proposed below:

1: The application can be made 2 points per tooth: one point in the cervical and another in the apical region of the tooth, dose of 3 J per point (indicated for molars);
2: Apply 2 stitches on the cervical (one buccal / palatal / lingual) and one stitch on the apical region, 2 J dose per spot (robust teeth with many restorations);
3: Apply 1 point to the cervical or apical area at a dose of 2 J per point (indicated for uniradicular teeth, in situations where several teeth are affected, or in case of pain after orthodontic activation).

Protocol for the production of reparative dentin (medium-term analgesia): The application should be done with the laser tip always perpendicular to the tooth or apical region. Preferably the red laser at doses between 1 and 2 J per point is used. According to the patient the clinician may choose one of the therapeutic modalities proposed below:

Immediate local analgesia may be the clinical parameter that indicates that the dosimetry for that patient is correct. Therefore, if the patient does not report immediate analgesia after the first irradiation, you may be repeating the application. But keep in mind that excessive repetition can inhibit reparative dentin biostimulation processes, despite causing immediate analgesia. Therefore caution is advised. Repeat only twice, and explain to the patient that the effect will come in the medium to long term.

1: The application can be made 2 points per tooth: one point in the cervical and another in the apical region of the tooth, dose of 1 J per point (indicated for molars);
2: Apply 2 stitches to the cervical (one buccal / palatal / lingual) and one stitch to the apical region, 1 J dose per spot (robust teeth with many restorations);
3: Apply 1 point to the cervical or apical area at a dose of 2 J per point (indicated for uniradicular teeth, in situations where several teeth are affected, or in case of pain after orthodontic activation).

Repeat this protocol every 72 hours for two weeks. That is: twice a week for two weeks.

The low power laser lymphatic drainage technique, developed and published by Profa. Dr. Luciana Almeida-Lopes, consists of laser irradiation in the main lymph node chains responsible for the drainage of the head and neck. The objective is to reduce edema in the postoperative period, postoperative dental procedures, herpetic vesicles, etc .; by activating the lymphatic drainage of the region affected by this edema.

Protocol: 2 points applied to each lymph node chain – preauricular, jugulo-digastric, submandibular and submental – on the affected side (right and / or left), with infrared laser and doses between 2 J and 3 J of energy per point). The frequency of application may vary from 2 to 3 times a week until regional edema is reduced.

The LED and laser light sources used for tooth whitening are directed to the patient’s mouth, not being able to penetrate or reach the uterine region of the operator. The laser light emitted from the equipment has a capacity to penetrate the oral tissues around 1 cm. Thus, they are not spread on the patient’s body or in the environment.
Therefore, pregnant professionals can perform the whitening being careful not to direct the lights to the abdominal region directly in the first trimester of pregnancy.

The low power laser acts on oral mucositis as a local anti-inflammatory, analgesic and healing agent, helping to heal oral lesions and improving the patient’s salivary flow, in addition to activating the patient’s local immunity.
For the patient, this means higher quality of life, since patients with Oral Mucositis have great difficulty in eating, swallowing and cleaning the oral cavity. In this sense, guaranteeing the patient the possibility of being able to eat properly, improves his general condition, fundamental for the success of the medical treatment in which he is.

There are currently preventive protocols, to be previously applied is the installation of mucositis and there are protocols for already established mucositis.

Protocol (preventive treatment):

1- Preventive Treatment: Begin treatment along with chemo / radiotherapy sessions. It is a preventive treatment since the formation of mucositis is not expected on the 4th or 5th day of antineoplastic treatment. The objective is to prevent lesions from appearing or to decrease their intensity. Applications can be daily (5 x per week) or according to patient availability.
2- Regions of application: Application should be in the 8 regions described below and the number of points in each will depend on the energy density applied: right and left jugal mucosa, palate, lower lip, upper lip, lingual and lateral dorsum. of the tongue and buccal floor. Irradiation should not be performed on the biopsy site or where the tumor lesion was located and a safety margin should be given for laser application 2 cm away from the lesion site. In patients with swallowing pain, extraoral application to the neck may be performed except in patients with a tumor in this region.
Energy per point: about 1 J per point
Number of Points: Apply 3 Points per Region

PROTOCOL (clinical mucositis):

1- Treatment of installed mucositis: Daily applications or according to patient availability until completion of chemotherapy or radiotherapy. Some clinicians continue this application for a few more days.

* If the mucositis is quite intense or covers a large area, give preference to the lowest dose applying at more points.

The objective of laser irradiation for xerostomia treatment is to stimulate the glands to perform their normal function (or close to normal) even in adverse situations, such as radiotherapy, Sjögren’s Syndrome and the use of some medications, which promote changes in this tissue.

The laser therapy protocol for xerostomia cases is:
• Infrared laser;
• Energy density: 2 J, 100 mW, continuous mode;
• Perform 2 points in each region corresponding to the location of the major salivary glands: sublingual, submandibular and parotid;
• 48/48 h or 72/72 h applications.

Frequency and duration of treatment: sessions can be held for 48/48 hours or 72/72 hours with a minimum of 5 sessions. If the case is a xerostomia caused by radiotherapy, it is ideal that the laser therapy is performed while the patient is undergoing radiotherapy characterizing the preventive treatment of the laser. In this case the applications may be daily or according to the frequency of radiotherapy sessions until the end of the antineoplastic treatment.

Laser therapy applied to TMJ dysfunctions has analgesic, anti-inflammatory, muscle relaxant action and assists in the repair of traumatized nerve fibers. Patients with trismus (of mixed origin) or on TMD treatment are indicated for treatment with laser therapy.
The laser application should be done at 5 points over the joint region: 1 point over the condyle, 3 points: one 1 cm ahead, another 1 cm above and another 1 cm below the condyle and the fifth point inside the condyle. outer ear towards the condyle. Also, if there is muscle pain, chewing-related muscles should be palpated and pain points (trigger points) should be irradiated.
The recommended energy per point is 3 J.
Irradiation at both TMJs is recommended using the infrared (invisible) laser, with applications every 72 hours while symptoms persist.
The use of laser does not eliminate the need for oral rehabilitation if patients need more complex treatment. The ideal is therefore to associate the conventional technique (myorelaxing plates, occlusal adjustment, etc.) with the laser.

The laser application protocol foresees the previous cleaning and drying of the surface (intra or extraoral). This improves laser penetration due to less light reflection, which happens to a greater degree when the surface contains water (water reflects more light). If the surface is not dry, this will not prevent the therapeutic action of the laser. What can happen is that the laser reaches the lowest depth of tissue penetration. This lower penetration also occurs when we employ lower powers. The lower the power used, the lower the laser penetration in the tissues.

Traumatic ulcer is a painful lesion characterized by a central ulceration area covered by a fibrin pseudomembrane, necrotic tissue remnants and microorganism aggregates, surrounded by an erythematous halo. Usually disappear between 10 and 21 days without leaving a scar. Laser therapy can be performed to accelerate ulcer healing as well as to relieve painful symptoms. In ulcers without painful symptoms, the indicated dose is: Red Laser, 1 J energy, 2 points, immediately after the appearance of the lesion and every 24 h. In ulcers with painful symptomatology, the previous dose may be repeated 3-4 times (according to the patient’s clinical report on pain). Usually 2 to 4 clinical sessions are held for the treatment of traumatic ulcers. Relief of painful symptomatology will determine the termination of treatment.

Trigeminal neuralgia is characterized by dysfunction of the trigeminal nerve (cranial nerve V), which carries information on the sensitivity of the face to the brain. Its dysfunction causes episodes of severe and stinging pain lasting from a few seconds to minutes.
Neuralgia has two forms: idiopathic – of unknown origin and usually chronic and secondary – usually caused by trauma of dental origin, such as extraction, endodontic treatment or even poorly adapted prosthesis. Regardless of the type of neuralgia, this type of involvement is usually refractory to conventional treatments and laser treatment is a clinically very effective option and is still a noninvasive technique with no side effects.
The diagnosis is made based on the patient’s report along with their clinical history, seeking to map the possible causes and symptoms. Aspects such as pain triggering factors should be considered (eg cold, chewing, ice water, etc.). Next, we seek to find out which branch of the nerve is affected from the region whose patient has painful symptoms. Trigger points are not always easily detected in these cases, but they are the points of intense pain that the patient can identify.
Laser therapy acts to promote analgesia by healing of injured nerve fiber or recovery of altered nerve threshold.
The beneficial action of the laser is associated with its local anti-inflammatory and analgesic effect by modulating nerve beam dysfunction (which is what characterizes the disease). The nerve transmission threshold returns to normal and the painful crises characteristic of neuralgia are avoided.
The application should be done along the path of the affected nerve, punctually, with a distance of 1 to 1.5 cm between the points with the following parameters:
– Laser at infrared wavelength (808 nm), energy density between 1 and 2 J. To avoid nerve neuroplasticity, where the optical fiber gets used to the stimulus, the irradiated dose should be changed every 4 sessions. about. Thus, the treatment should be started with a lower energy per point, gradually rising until reaching the maximum dose (which will be fixed when it reaches the tenth session). If the lesion persists, the reverse path should be taken, this time decreasing the dose by point gradually.
In general, there will be 10 to 20 sessions that can be done 2 to 3 times a week (being careful to give a minimum of 24 hours between one application and another).
Also, in order for the effects of the Laser to be significant, it is very important not to associate the treatment with CARBAMAZEPINE (TEGRETOL). If the patient is already using it, one should gradually reduce the medication.

The harmful effects that the laser can cause are limited to the eyes. The manifesting eye lesions vary according to the wavelength of the laser light. Red and infrared lasers used in phototherapy can cause the following effects:

Visible light from 400 to 780 nm (the red laser used has an approximate wavelength of 685 nm):
The retina suffers thermal and photochemical lesions as all other elements of the eyeball are transparent to these beams.
Infrared rays A, from 780 to 1,400 nm (the infrared laser used has an approximate wavelength of 830 nm):
These wavelengths are the most dangerous for the eye, which does not perceive the beams of this length, but focuses them on the retina, where they cause severe burns and photochemical lesions of the retina. In addition, some of these beams are absorbed by the lens, leading to turbidity, that is, cataract.
This means that we can never look directly at the laser beam and the use of goggles by the patient, operator and assistant is indispensable.

The values ​​usually practiced for Laser Therapy and charged per application session, are usually calculated according to the clinical time of the professional in question (for each office and reality the dentist must make and adjust this calculation).
There is an important distinction for some types of treatment, which may be charged for packages. These are the cases of treatment of Paresthesias, Paralysis and TMD, Xerostomia and Mucositis. For virtually the laser is the treatment alone, and usually involves some clinical sessions (minimum 5 and maximum 20). The packages vary from region to region in Brazil, based on the average consultations practiced in each region of the country. Regarding the way to charge the other treatments, which associate the laser with the conventional treatment, such as cases of extraction, hypersensitivity, periodontics, for example, an increase of 15 to 20% in the total treatment value is usually calculated (with reference to values ​​practiced in the dentist’s office in question).

Photodynamic Therapy (PDT) – PhotoDinamic Therapy (PDT) is the association of a photosensitive agent with a specific light source, with the purpose of performing the microbial reduction. One of the protocols indicated for PDT in periodontal pockets and root canals is the association of the 0.005% methylene blue dye (as a photosensitive agent) with the laser emitting at the red wavelength.

PDT Protocol for Periodontics:
1. Performing scraping and root polishing;
2. Applying the dye with a syringe to periodontal pouches;
3. Wait 5 minutes (time for dye to penetrate microorganisms);
4. Radiate with red laser (Adjustment for Photon and WLII: NORMAL MODE, 660 nm, 100 mW power, 140 J/cm² energy density, continuous mode, 40 seconds per dot irradiation time). (Set for Flash Lase and XT: 4 J per point);
5. Apply to each bag one point per lingual and one per buccal;
6. Wash thoroughly with saline until total dye removal.

PDT Protocol for Endodontics:
1. Performing root canal instrumentation;
2. Application of the dye with an inner root canal syringe;
3. Wait 5 minutes;
4. Radiate with red laser (Adjustment for Photon and WLII: NORMAL MODE, 660 nm, 100 mW power, 140 J/cm² energy density, continuous mode, 40 seconds per dot irradiation time). (Setting for Flash Lase III and XT: 4 J per point);
5. Radiate 1 point (incisors, canines and premolars) or 2 points (molars) at the root canal entrance;
6. Wash thoroughly with saline until total dye removal.

In Periodontics, the technique should be done immediately after root scraping and may also be done before scraping if bacteremia decrease is desired. In endodontics, PDT can be performed after root canal instrumentation and before canal obturation.

One of the protocols indicated for PDT in periodontal pockets and root canals is the association of 0.005% methylene blue dye (as a photosensitizer) with laser irradiation at the red wavelength.
Application of the protocol should not be repeated in the same session.
The PDT technique supports the periodontal and endodontic treatment. Therefore, it can be performed every time root scraping is performed or whenever the root canal is instrumented or filled. In most cases, 1 or 2 sessions are sufficient for treatment success.

The photosensitive agent Methylene Blue used in the performance of photodynamic therapy (PDT) comes in a solution with a concentration of 0.005%, and therefore water is the vehicle. In some cases, as in endodontics, some professionals associate Methylene Blue with gels or creams to facilitate application.
In the case of periodontics, we recommend the use of methylene blue in solution. For successful therapy it is important that the dye penetrate to the bottom of the periodontal pocket and the liquid form allows the product to flow better. Before applying the product we measure the depth of the bag with a probe and place a stop on the syringe needle with the height obtained on the probe. Injecting the methylene blue, we insert the syringe needle into the periodontal pouch until it stops. Once applied, the dye should remain for 5 minutes before the start of laser irradiation.
Irradiation can be done transcutaneously because the laser has enough energy to photosensitize Methylene Blue even after crossing the gum.
There are 2 times to perform PDT in periodontics: before and / or after scraping. As the goal of PDT is microbial reduction, by doing the procedure before scraping we reduce bacteremia and circumvent the problem of gingival bleeding that hinders the penetration of methylene blue.
PDT may be repeated in the control phase if infection is still present.

There are two different concentrations of methylene blue. One at 0.005% and one at 0.01%. DMC has chosen to produce both concentrations due to the fact that, in Brazil, these two lines of work exist. Each advocates one of these concentrations. We have been advocating use at 0.005% because as it is more dilute, so as it is more diluted we are more certain that light will penetrate the entire bag making the PDT a better action. We do not recommend the use of intra-radicular or intra-periodontal fiber (fiber introduced into the root canal in endodontics, or into the pouch in the case of periodontics). For this reason, we indicate the box with syringes at 0.005%. Keep the product for 5 minutes in the periodontal bag just by bathing it, and then apply the red laser for 1:30 min, which makes approximately 13 J of energy per proximal. Then wash with serum or 10-volume hydrogen peroxide if the cervical tooth is slightly stained.

We can work quietly with Methylene Blue in this region. However, it would be interesting to use the concentration of 0.005%, as it has a lower possibility of mucosal staining. If staining occurs, hydrogen peroxide at 10 vols may be used for cleaning.

When you increase the laser application time proportionally, you are increasing the energy dose and this may inhibit the desired response. In short, if you apply 4 J/cm², 2 times at the same point, therefore, you will be applying in place 8 J/cm².

Although the ILIB technique is based on the use of red laser at 100 mW (coincident with those present in its two equipments), the technique is only possible with a larger fiber diameter (not to generate lesions in the application areas) and with software that ensures the integrity of the laser diode stays on for so long. That is, it is not any red therapeutic laser that can be used in the aforementioned technique.

The indication and suggestion of the ILIB is that it is performed in the radial artery, which is in the wrist or wrist. We do not indicate that it is performed in the brachial region, much less in the carotid region.

The fiber is 600 microns and the area is 0.0028 cm² (fiber output – valid for calculations if it touches the fiber at the point of application – normally, with the spacer, this area gets 10 x larger, which leads to 10 x longer application time than calculated for contact – DMC equipment already considers this). Corroborating: the spot area of a 600 mm fiber in contact is the core area of the fiber itself, ie 0.0028 cm² (2.827 x 10-³ cm²). However, with the spacer the spot increases with a resulting increase of the area by 10 x, hence the area is 0.028 cm².

Protocol for Hyperchromies:

1- Sanitation;
2- Application of blue LED across the face for hydration and local swelling;
3- Surface pickling (peeling with mandelic, salicylic or glycolic acid);
4- Application of blue LED on hyperchromy;
5- Use of photo protector.

Note: The application of blue LED is performed by regions that comprise the extent of light deposition, whose time depends on the client’s phototype, as follows:

Phototypes 1 and 2: 3 minutes per region.
Phototypes 3 and 4: 2 minutes per region.
Phototypes 5 and 6: 1 minute per region.

In the treatment of dark circles (by local melanin), the client should wear goggles, where you will apply the blue LED on the bottom of the glasses (with time dependent on the phototype) and finish with the infrared laser on the preauricular lymph nodes. In the physiological eye (due to tiredness, alcohol, migraine, etc.), goggles and infrared laser in the preauricular lymph nodes only, ie, the blue LEDs do not apply on site.

If the treatment is for decontamination prior to comedo extraction as indicated by blue light, the protocol can be initially performed every day, after decontamination there the treatment aims at healing with the red laser.

Therapeutic lasers have no major action on cysts, including Baker’s cyst. As a suggestion, to reduce pain, the ILIB technique, by promoting endorphin release, has important analgesic effects, even in joints. Therefore, in addition to medical treatment, the free radical-fighting technique can decrease your sister’s painful sensitivity.

Perform a red laser at the burn site daily and infra laser at the lymph nodes for at least 7 days. Since her type photo is 1, put 3 joules per point.

Apply directly to the soft tissue, with the infrared laser being deep tissue and red on the surface, especially those that surround the wound. As for metals, no problem, just avoid making direct application on them, as this will work as mirrors.

The ratio of Laser Peroxide bleaching gel (25% or 35%) is: 3 drops of hydrogen peroxide to 1 drop of thickener.
If the whitening is for both upper and lower arches, we usually use 30 drops of hydrogen peroxide for 10 drops of thickener, as this amount is sufficient to cover the upper and lower teeth.
Mixing of the phases should always be done immediately before application.

Patients undergoing treatment with isotretinoin may undergo photoactivated tooth whitening any time after the use of the drug.
We emphasize that the possible dental pigmentation due to the use of the drug can lead to a difficulty in tooth whitening.
Cases of bleaching after isotretinoin use are not predictable and may not respond satisfactorily. In any case, we suggest that the patient be informed of this difficulty and that the whitening attempt be made.

Dental bleaching performed with the office technique (Laser) or made with trays (homemade) has the same mechanism of action, which is the breakdown of pigments (organic molecules) into smaller molecules. This breakdown occurs by the action of free radicals released by the whitening gel (hydrogen peroxide or carbamide). Understanding the process demystifies the question of which technique promotes the most lasting results.
The duration of tooth whitening is much more related to the new contact with eating pigments and habits. Thus each individual has a different answer. What it usually looks like is that regardless of the technique the whitening has a long lifespan, an average of 2 years (some cases some others a little less).
Either way, the teeth can be whitened again if the patient needs or desires.

25% hydrogen peroxide:
– young patients;
– Teeth that are not too darkened;
– teeth with broken enamel;
– Teeth with retraction and incisal and cervical wear;
– Patients who used orthodontic braces and Slaice teeth;
– Patients with sensitivity;
– Patients who use mouthwash. Ex .: Listerine, Plax, etc .;
– When you need the 2nd bleaching session and the patient showed sensitivity in the 1st session, or when there is no deadline between the 2 sessions of at least 7 days.

35% hydrogen peroxide:
– Patients dissatisfied with the original color of their teeth;
– teeth darkened by age;
– Tetracycline stained teeth;
– teeth stained by cigarette, tea, coffee, etc .;
– Patients without sensitivity;
– Non vital teeth.

Yes, although both have the same function, they act differently: fluorine occludes the dentinal tubules, preventing fluid from reaching the pulp, while potassium nitrate has an analgesic effect on nerve fibers, not allowing them to repolarize , thereby decreasing the sensitivity.

Between 15 and 17 years. It is important that the practitioner takes a radiograph for clinical evaluation and finds that the rhizogenesis of the teeth to be whitened is already completed.

The duration of tooth whitening will depend on factors such as eating and oral habits, use of medications, mouthwash or drugs, and quality of oral hygiene, etc.
It is important to follow up this patient, and when necessary make a whitening for maintenance every 1 or 2 years preventing color regression.

No. The LEDs associated with the diode laser in lightening emit a type of light radiation which, when absorbed by the red-colored hydrogen peroxide bleaching agent, will result in photochemical and photothermal effects targeting the molecules. darkened, enhancing the tooth whitening process. This mechanism generates a minimum temperature increase without damage to the pulp tissue, as they heat the gel and not the dental structure.

The gel should remain between light activations and gel rest, between a minimum of 10 minutes and a maximum of 15 minutes, because the success of the treatment will depend on the ability of the bleaching agent to penetrate to the darkened pigments and remain there long enough to oxidize them. pigments, breaking the molecular chains. It is not advisable to leave any longer, thus avoiding possible dental sensitivity.

Properly follow the step-by-step teeth whitening and follow some recommendations:
– Make a good anamnesis, with medical and dental history.
– Complete a clinical examination for caries, retractions, wear, restorations with infiltration.
– Use the appropriate whitening gel: red, neutral pH 7.0, which is more absorbent in the wavelength used in the equipment used.
– The equipment used must have adequate light intensity.
– Follow the protocol recommended by the manufacturer.
– Be aware of the expectation of the patient and the professional.

If the staining is grade I and grade II, the result will be satisfactory, for this a protocol will be established with the largest number of whitening sessions in the dental office.
If staining is grade III, the combination of photo-activated whitening and home whitening is recommended.
If the staining is grade IV, the prognosis is unfavorable.

First you have to do photo-activated whitening. During teeth whitening these fluorosis spots should be protected (covered) by the gingival barrier itself.
Unfortunately whitening does not solve the problem, it will only soften these stains by whitening your teeth. After tooth whitening it is recommended to use micro-abrasion when necessary.

Yes. As long as photoactive whitening is done. Home whitening is contraindicated.

It is recommended to wait at least 7 days, but ideally 14 days to wait for full oxygen release and prevent the fall of resin restorations.

It will not always be necessary to change them. We should just polish them a few days after the teeth whitening is over.

It is recommended to have a maximum of 4 sessions, expecting a minimum of 7 days (1 week) between these sessions. This wait is recommended because, during the whitening treatment, the process suffers decrease in the possibility of the whitening process, obtaining the optimum whitening point, called saturation point, where from it can occur structural changes of the enamel and dentin, including decreased enamel microhardness. The clinician must know when this is the point before ceasing teeth whitening.

Responses for each patient are quite diverse, depending on the level of penetration of the bleaching agent through enamel and dentin, and may also be related to excessive thickness loss or presence of enamel cracks, cervical dentin exposure or due to denture injuries. abfraction, erosion and abrasion or even due to the anatomy of the cement-enamel junction, which has exposed dentin.

It also interferes with sensitivity:
– pH of bleaching agent;
– High energy doses, without gaps between them;
– Hydraulic pressure of the whitening agent on the exposed dentinal tubules;
– age of the patient;
– Intake habits of beverages and foods with acidic pH. Ex .: Coke, Guarana, Orange, Lemon, Apple, Tomato, etc;
– orthodontic socket;
– Presence of caries or restorations with infiltration;
– Use of mouthwashes. Ex .: Listerine, Plax, etc .;
– Patients with spontaneous sensitivity.

In these cases it is recommended to use 25% hydrogen peroxide or to make only 2 applications of 35% gel and to perform the whitening in more than one session (day of application).

After tooth whitening, apply therapeutic laser to the teeth with sensitivity.
– The use of desensitizer can be applied with felt after laser therapy, being careful not to heat the tooth and let it act for 2 minutes on the dental surface.
– When necessary to prescribe oral analgesic.

Yes. As long as photo-activated whitening is done. Home whitening is contraindicated.

The appearance of white spots after tooth whitening is usually associated with dental dehydration that occurs during treatment. This dehydration makes evident patches of mild fluorosis and hypoplasia that already exist and are imperceptible under normal hydration conditions. The opaque appearance usually disappears after a few hours or as soon as natural moisture is re-established. For these cases, tooth whitening suspension is not required.
If, however, the patient already has white spots before the whitening treatment, and these are superficial, it is indicated one week after the end of the whitening the removal by the microabrasion technique.
Another situation, which is frequent in patients who have just undergone orthodontic treatment, is staining caused by the presence of adhesive residues. After explorer diagnosis, the patch should be completely removed and bleached in the next session.
The most unusual case is when intrinsic stains are highlighted after bleaching. This situation is related to the lack of careful diagnosis prior to the whitening procedure. If this diagnosis is made correctly, regionalized bleaching should be done, ie the application of the whitening gel only on the darker area in an attempt to approximate the dental color of the different dental thirds.
Thus, it is essential to diagnose the presence of blemishes during the clinical examination. Relative isolation followed by light tooth drying will facilitate this diagnosis by identifying “hidden” stains with detail.

Medicines that contain heavy metals (such as some anabolic steroids, vitamin complexes, and some acne medicines) can have a tooth-staining effect. This is because of the affinity of these chemical elements for bone tissues and also for the affinity for dentin, accumulating in these tissues and causing darkening.
The success of tooth whitening when there is staining caused by these drugs is unpredictable and the desired result may not be achieved.
Therefore, during anamnesis we should investigate the use of medicines that may have in the composition of these metals, with the intention of guiding the patients regarding the degree and speed of bleaching.

After bleaching, we should advise patients not to drink beverages / foods containing pigments such as red wine, coffee, soft drinks with color (especially coke), naturally and artificially colored juices, sauce, black tea, ketchup, mustard, besides not smoking or using lipstick.
Dehydration by isolation of the oral cavity and exposure to air during the whitening session makes the teeth have a tendency to absorb liquids in the oral cavity within 24 hours after the session is over, since this is when the structure dental regains its initial hydration. Therefore, the recommendation of not eating food during this 24-hour period should be carefully respected.
The dietary restrictions should still remain for another week, because after this period will be held the second whitening session and it is interesting that there is no more pigment incorporation in the tooth, allowing a better final treatment result.

The whitening agent used for dental bleaching performed in the dental office is a Hydrogen Peroxide gel, and can be found in concentrations of 25% and 35%.
DMC has developed a gel called Lase Peroxide (25% or 35%) that has 2 solutions (Hydrogen Peroxide and Thickener) that must be mixed in a ratio of 3 drops of hydrogen peroxide to 1 g of the thickener. This ratio gives the gel a viscous consistency, preventing the gel from flowing into the oral tissues.
Hydrogen peroxide, through its chemical decomposition, releases free radicals to the tooth, promoting the breakdown of pigment molecules found in the teeth. This chemical reaction can be accelerated through light and / or heat. The preferred method is to use light sources such as LEDs and hybrid LEDs (LED + low intensity laser) to accelerate this reaction. In order for the whitening gel to interact with these light sources, which are usually blue, it must be red in color.
It is important that the light emitted is absorbed by the whitening gel, which in turn has its color changed indicating that the chemical reaction is taking place. This color change can range from red to orange or from red to transparent. In this sense, we indicate the use of whitening gels that change from red to orange, because when the gel becomes transparent there is no longer interaction between it and the light source. Thus, the gel is also responsible for absorbing the lights emitted by the equipment, preventing the tooth from receiving all the light emitted.

Procedures prior to tooth whitening are critical to successful treatment.
After specific anamnesis, clinical and radiographic examination, prophylaxis is a very important item for teeth whitening.
In cases where supra and / or sub gingival scraping is required, these procedures should be performed in sessions prior to the bleaching session. These scraping procedures can cause gingival bleeding that prevents proper adaptation of the gingival barrier, and can cause dentin exposure triggering a dental sensitivity picture.
In the whitening session, tooth prophylaxis should be performed immediately before whitening. The indicated prophylaxis materials are: pumice stone, water and Robinson brush (or rubber cup). We should not at this time perform sodium bicarbonate jet prophylaxis as it is a hydrogen peroxide neutralizer (Lase Peroxide Sensy Whitening Gel, concentration of 35% or 25%).
If prior bicarbonate jet prophylaxis is required, it should be performed at the previous session, about 3 days before the whitening session. This does not exclude pumice stone prophylaxis immediately before bleaching.

Before you start lightening gel photoactivation, perform:
• The patient’s lips should be retracted with a lip retractor of his choice (we suggest the retractor who has the tongue positioner);
• Pumice and water prophylaxis;
• Gingival barrier placement and LED curing;
• Protection of the lip and groove mucosa with Vaseline or a lip balm of your choice;
• The handling and application of the whitening gel in both arches.

The photoactivation of the gel will depend on the equipment you have. Following are the bleaching gel activation protocols for each type of DMC equipment:

Whitening lase
• Fotoact the gel for 3 minutes covering both arches;
• Leave the gel in contact with the tooth without activating for 2 minutes;
• Fotoact the gel for another 3 minutes;
• Remove excess gel first with a sucker and then with a damp gauze;
• Reapply the gel;
• Repeat this process two more times.

Whitening Lase Light
• Photoactivate the gel for 6 minutes to interleave the upper and lower arch every 1 minute between the archs – leave the gel in contact with the tooth without activating for 4 minutes;
• Remove excess gel first with an adapted saliva sucker and then with a damp gauze;
• Reapply the gel;
• Repeat this process two more times.

Whitening Lase II
• Photoactivate the gel for 6 minutes to interleave the upper and lower arch every 1 minute between the archs – leave the gel in contact with the tooth without activating for 2 minutes;
• Remove excess gel first with a sucker and then with a damp gauze;
• Reapply the ge;
• Repeat this process two more times.

Ultra Blue IV
• Visually divide the patient’s arch into three sectors: central, right and left;
• Fotoact each sector for 3 minutes;
• Leave the gel in contact with the tooth without activating for 2 minutes;
• Remove excess gel first with a sucker and then with a damp gauze;
• Reapply the gel;
• Repeat this process two more times.

There are reports in the literature that discuss whether or not there is a carcinogenic effect of contact between carbamide peroxide or hydrogen peroxide used in tooth whitening and oral mucosa. These studies conclude that the above peroxides have very little or no carcinogenic potential.
Free radicals produced from peroxide decomposition are believed to have the power to attack cellular DNA and may cause a mutation, but the effects of these radicals are minimized by the action of enzymes present in the oral cavity, such as catalase.
Although the mechanisms that attempt to explain the action of peroxide on soft tissues are not yet fully elucidated, the possibility of a carcinogenic potential is not ruled out.
Therefore, in patients who have a history of neoplasms we contraindicate home bleaching, since there is a higher risk that the bleaching agent comes into contact with the mucosa and that mucosa is more susceptible to the effects of peroxide. In these cases, the most appropriate is the office whitening that minimizes the contact of the whitening agent with the soft tissues and their swallowing.

This issue of dental treatments in lactating or pregnant patients is a current issue of colleagues. It is important to be aware of these cases and to know how to guide the patient regarding procedures, especially when we have new technologies involved.
Tooth Whitening is an aesthetic treatment that can be performed by 2 techniques: home or office.
The homemade technique (with trays) is contraindicated for pregnant or lactating patients due to gel contact with oral tissues and risk of swallowing. Ingestion of peroxides can do many harm to the mother.
The office whitening technique is safer, because in this case there is no contact of the gel with soft tissues and the risk of swallowing is eliminated. In this case, we use lights (LED and LED / Laser) to activate the whitening gel. These lights are not ionizing radiation (do not cause genetic mutations) and, in the parameters that are available on equipment, are safe and have no ability to cause harm to either the patient or the fetus.
It is important to explain that laser light emitted by DMC equipment has an ability to penetrate oral tissues by less than 1 centimeter. Thus, they are not spread on the patient’s body or in the environment.
It is noteworthy that directed irradiation to the abdominal region (fetus) is contraindicated in pregnant patients in any case.
Although we have control over the LED and laser lights during tooth whitening, cosmetic procedures in lactating or pregnant patients should be postponed, and performed after pregnancy or breastfeeding period. Any problem the patient has with her pregnancy or the baby can be attributed to the whitening and this would cause discomfort for everyone.

Carbamide peroxide decomposes to hydrogen peroxide which, at high concentrations, is irritating to the mucosa. Therefore, home bleaching is done with low concentrations of peroxide. However, some patients may have a more sensitive peroxide mucosa even at low concentrations. One of the ways to avoid contact with the whitening gel during home treatment is to instruct the patient to put in an adequate amount of gel that does not allow it to leak from the tray.
In your case, as the patient has mucosal irritation, we suggest that you stop home bleaching and perform the procedure in the office, as it enables soft tissue protection with the gingival barrier. Thus, the gel does not come into contact with the patient’s mucosa and yet you have control of all treatment steps.

As a rule, we have a minimum age for whitening that is given by the time of closure of the dental apex. In general, the second premolars are the last dental elements to erupt around age 13 or 14. From there, there is a time interval of about 3 years for complete closure of the root apex. Thus, we are based on a borderline age between 16 and 17 years so that the bleaching can be done, and even at this age, we recommend performing periapical rediographs of this region to analyze the state of the roots.
There are exceptions, for example, in cases of adolescents under 16 who have aesthetic impairment of smile and whitening is indicated. Thus, the procedure can be performed in the areas of greatest evidence of smiling, for example from canine to canine, with the consent of the guardian.

The In-Office Tooth Whitening Protocol includes clinical sessions (between 1 and 4) which should have a one week break between sessions. After whitening, the maintenance or reinforcement of tooth whitening can be performed after 1 year.
Medicines containing ferrous sulfate and other heavy metals may result in dental darkening by the affinity of these compounds for dentin and bones. Thus in the anamnesis should be investigated the administration of medication in general, then relate to the possible difficulty of teeth whitening.

A few situations contraindicate tooth whitening.
Patients using medicines containing ferrous sulfate or other heavy metals may have their teeth stained due to the affinity of these compounds for bones and dentin. Roacutan and Acne medicines can interact with the LED and laser light emitted by the bleaching equipment and have the side effect of skin blemishing. Therefore, tooth whitening should be conducted with caution, for example with the use of skin protectors or filters (such as sunscreens).
Patients who have or have had head or neck cancer should also receive special attention, as the affected region should not receive laser irradiation. Thus, the lightening should be performed only with the LED (the laser should be off).

The molecules of the active agent in the whitening gel, hydrogen peroxide, and its by-products, free radicals, have a small molecular weight. In other words, they are small molecules that easily pass through enamel prisms and dentinal tubules. Thus, the use of acid conditioning becomes unnecessary.
Bleaching protocols should be as conservative as possible and therefore do not include acid etching of the enamel.
Moreover, there is currently a major concern in the development of bleaching gels in the sense that they should not have acidic pH during their application so as not to cause demineralization of the dental enamel.

Teeth polishing should be performed at the end of each tooth whitening session. We recommend polishing with polishing paste impregnated felt discs that should be used at a low rotation contra-angle. It is interesting to use the desensitizing gel on the teeth and rub the felt. Polishing restores smoothness to the dental structure, making it difficult to adhere to pigments that can re-pigment the tooth.

Tetracycline dental staining cases are actually more resistant to whitening. The first step in treatment is to identify the degree of staining. Cases with grade I or II are more favorable, while cases with grade III or IV have a banded stain with marked contrasts between them.
Regarding the protocol, we recommend a greater number of office sessions (about 3 to 6 sessions) and the association with home whitening. If the patient has clear bands with different pigmentations on the same dental element, during office sessions the whitening should be sectored, first working the regions of the tooth that are most pigmented. This maneuver is possible by placing the whitening gel only in the darker strip (see attached photo). Thus, what is sought in most cases of tetracycline is the homogenization of tooth color through bleaching.
Another suggestion is to increase the exposure time of the gel to light from 3 minutes in each arch (as the standard protocol dictates) to 5 minutes in each arch.
In general, patients have sensitivity due to the more intensive and extensive bleaching protocol used in these cases. For patient comfort, we recommend laser therapy after office whitening and fluorotherapy sessions.

The quality of teeth whitening is influenced by the presence of light (LED or LED + LASER), but also depends on the power (or intensity) used. Another relevant factor for the gain in clinical time is the tip of the equipment, which can be from the size to cover 1 tooth, 3 teeth or the entire dental arch.
Equipment with blue LEDs has the ability to activate the whitening gel when they have intensities greater than 250 mW / cm². Lower intensities are not effective for time saving in the office teeth whitening technique.
The devices that have LEDs and LASER in the same equipment have a differential of associating the two lights for activation of the whitening gel, and still have the effects of laser therapy to reduce the sensitivity during the whitening. In any case, it is also essential to consider the emitted intensities in order to make a comparison between equipment.

No. The use of the curing light is not indicated for the activation of the whitening gel due to the heat that can be generated in the dental structure, leading to irreversible pulpitis. Another disadvantage is the reduced lifetime of the device, which is not designed from an engineering point of view to be used in this way.
Therefore, if you choose to use a light curing equipment, it is recommended that it be as short as possible directed to the dental structure, a maximum of 10 seconds per tooth and away from the dental element.
The most suitable protocol for dental bleaching with the in-office technique today has been suggested for Whitening Lase II equipment:
WHITENING LASE II PROTOCOL
Before you start lightening gel photoactivation, perform:
– selection of teeth colors Central and Canine Incisors (sup and inf)
– the removal of the patient’s lips with a lip retractor of your choice (we suggest the retractor that has the tongue retractor as it is more comfortable for the patient)
– pumice and water prophylaxis (bicarbonate jet prophylaxis is contraindicated at this stage, as bicarbonate counteracts the action of hydrogen peroxide, preventing bleaching). It is also important to avoid re-contamination with teeth saliva so as not to have a physical saliva barrier preventing whitening.
– re-humidification of teeth with damp gauze (teeth must be damp, as present water collaborates as a vehicle for free radicals released by gel decomposition to penetrate the dental structure)
– the placement of the gingival barrier and its light curing with the LED itself (the gum barrier should not cover more than ½ millimeter of cervical enamel so as not to interfere with whitening)
– protection of the lip and groove mucosa with petroleum jelly or a lip balm of your choice (as accidental contact of the gel may lead to discomfort and burning, greatly impairing the course of treatment)
– manipulation of the whitening gel. Always at a rate of 3 drops of hydrogen peroxide to one drop of thickener. For both arcades, the amount of 30/10 is sufficient. One can choose 35% or 25% hydrogen peroxide. The 25% is indicated for teeth with a history of sensitivity and for young teeth. Gel handling should be performed immediately prior to application.
– application of the whitening gel in both arches. The best way to apply the gel is with a disposable syringe as application becomes safer and faster.
– photoactivate the gel for 6 minutes to interleave the upper and lower arch every 1 minute (eg: upper 1 min + lower 1 min + upper 1 min + lower 1 + upper + 1 min lower)
– leave the gel in contact with the tooth without activating for 2 minutes
– Remove excess gel first with a sucker and then with a damp gauze.
– manipulate again the amount of 30/10 drops and reapply the gel.
– repeat this process two more times.

After removal of the gel and gingival barrier, the desensitizing gel should be applied to the teeth and felt disc polishing (from the Lase Peroxide kit).
The post-whitening recommendation is to restrict foods / beverages containing pigments for one week.

Definition: Roacutan® (isotretinoin) is 13-cis retinoic acid, an oral retinoid. Isotretinoin is a substance derived from vitamin A.
Indication: Treatment of severe forms of acne (nodulocytic and conglobata) and acne resistant to previous therapies. Acne is a disease of the pilosebaceous follicles (formed by the sebaceous gland and hair) that can occur on the face and chest. Its main causes are:

• Altered follicle keratinization, which causes obstruction of the follicular orifice.
• Hypersecretion of the sebaceous gland.
• Bacterial proliferation, especially Propionibacterium acnes. With sebaceous retention, the microorganism proliferates and the inflammatory process is triggered.
Isotretinoin, the active ingredient in Roacutan® (isotretinoin), is the only drug that acts on all factors that cause acne.
Action: It acts on the process of follicle keratinization (normalizing altered follicular keratinization) and decreases sebum production. Thus, the conditions for bacterial proliferation cease.
Side Effects: (are reversible and disappear at the end of treatment) – are dose-dependent (many of these adverse reactions have been observed with long-term treatment only) – dryness and cracking of the lips; – dry nose and eyes (may cause slight nose bleed and conjunctivitis); – the skin may become drier and more sensitive, possibly causing itching; – Other effects such as mild hair loss, nail fragility, headache or muscle or joint pain may occur less frequently.
Care during treatment: – Isotretinoin causes fetal (teratogenic) malformation. Women cannot be pregnant when they start treatment and should not become pregnant within one month after treatment. – Roacutan® (isotretinoin) is also contraindicated in patients with hepatic impairment, pre-existing hypervitaminosis A, excessively high blood lipid values, allergy to the drug or any substance contained in the capsule.
– PATIENT WHO IS TAKING ROACUTAN® (ISOTRETINOIN) SHOULD NOT EXPOSURE TO THE SUN WITHOUT PROTECTION.
Explanation: Topical and systemic retinoids make the skin more sensitive to the sun and cyclins and may cause phototoxic and photoallergic reactions. Phototoxicity and photoallergy cause photodermatoses, also called photodermatitis or lucides. These comprise a large number of abnormal skin reactions caused by ultraviolet light or the visible spectrum of light.
Phototoxic reactions (phototoxicity):
Phototoxic reactions result from chemically induced reactivity to ultraviolet light and / or radiation on a non-immunological basis. As far as we know, phototoxic reactions occur within a dose-response logic, with the intensity of the reaction being proportional to the concentration of the chemical and the amount of radiation at a given wavelength.
Phototoxic reactions are manifested by an immediate burning sensation, erythema, edema, sometimes vesiculation and blisters. The burning sensation is more pronounced than those seen with ordinary sunburn, but is relieved in the shade. Late erythema and edema may appear after a few hours and even one to two days after exposure. In the most severe reactions, blisters may appear. Localized hyperpigmentation may be noted after the reaction and in some cases may be the only manifestation. The intensity of the disease will depend on the amount of radiation, the type of skin, the place of exposure and the concentration of the substance. Phototoxic reaction lesions are confined to light-exposed areas of the skin, typically in one or more areas of the face, ear tip, neckline “V”, neck, neck region, forearm extensor surfaces, and back of the hands.
Photoallergic reactions:
Photoallergic reactions (photoallergy) are distinguished from phototoxic reactions by the immunological nature of the response, which occurs only in individuals who have previously been sensitized by simultaneous exposure to photosensitizing substances and appropriate radiation. Photoallergy seems to involve biological processes similar to those of allergic contact dermatitis, except for ultraviolet radiation, in the conversion of hapten to full allergen. The diagnosis of photodermatoses is often suggested by the distribution and character of skin lesions. Photoallergy frames require, for confirmation, a more thorough investigation including the photopatch test, which should be performed by a specialist (dermatologist) familiar with the technique.
Photoallergic reactions are usually characterized by eczematous lesions, with erythema, edema, infiltration, vesiculation and, in the most intense cases, blisters. Lesions may extend beyond exposed areas, recurring in previously covered areas. Disseminated mild dermatitis may be observed. As dermatitis subsides, pigmentary changes and skin thickening may become prominent. Some patients react to extraordinarily small amounts of light energy. The wave compromises responsible for photoallergy are in the ultraviolet long wave (UVA) range. A serious complication of photoallergy is the development of a persistent reaction to light. The disease is characterized by extreme photosensitivity that persists despite the removal of all contact with the photoallergen. An enlargement of the light’s action spectrum may occur, causing small exposures to ultraviolet radiation to trigger photosensitivity.
Photosensitivity reactions caused by various agents
1) By systemic action:
a) antiarrhythmic drugs: amiodarone, methyldopa, propanolol, quinidine;
b) antibacterials: tetracycline, dimethylchloretracycline, nalidixic acid;
c) sulfamidic oral antidiabetics;
d) non-hormonal anti-inflammatory drugs: piroxicam, benoxiprofen, acetyl salicylic acid (AAS), phenylbutazone and oxyphenylbutazone, ibuprofen;
e) antineoplastic agents (metrotrexate, vinblastine, 5. fluorouracil);
f) quinine – chloroquine derivatives;
g) diuretics – thiazides: chlorothiazides, furosemide;
h) retinoids: isotretinoin, etretinate.
2) By topical action:
a) antifungals: griseofulvin, ketoconazole;
b) dyes: acridine, eosin, methylene blue, toluidine blue, blue 35, fluorescein, cane rose, diphenylethylene (stilbene), neutral red;
c) petroleum derivatives: coaltar, creosote, fish, benzo (a) pyrene, anthracene, phenanthrene, fluorantrene, ß-methylanthracene;
d) phytophotodermatitis: furocoumarin, psoralenic, family of umbelifera – celery, parsley, carrot (compositae) Chrysanthemum, sunflower.
Plants of the families of moraceae (fig, jackfruit, breadfruit) and rutaceae (citrus fruits in general);
e) fragrances: methylcoumarin, musk ambrete;
f) sunscreens: PABA and glyceryl-PABA, oxybenzones, parsol, eusolex, benzophenones;
g) halogenated topics: tribromosalicylanilide (TBS), trichlorocarbanilide (TCC), n-butyl 4.chlorosalicylamide, hexachlorophene;
h) Other: cyclamate, cadmium, riboflavin, sulfonamides.
Isotretinoin x tooth whitening: CONCLUSIONS / HYPOTHESES / SUGGESTION OF CONDUCT. LED radiation to the skin in patients treated with Roacutan® or another generic Isotretinoin mimics sun exposure since the wavelength of the LED is included in the visible spectrum of light. Isotretinoin promotes skin fragility (Williams; Elias, 1981; Elias et al., 1981) contraindicating epilation and surgery at least 6 months apart (Layton et al., 2006). In addition, according to the Ministry of Health (Annex 3), isotretinoin is an agent that can cause photosensitivity reaction, ie, in combination with light can cause a phototoxic or photoallergic reaction. Although some studies indicate that only sunscreen is already sufficient and that many patients have not reported skin problems during summer treatment with Roacutan® (Kunynetz 2004), there is still a lack of work to prove that sunscreen use in the region to be treated. irradiated with the LED during tooth whitening is sufficient to prevent any damage to the skin. The dose and time of exposure will influence the effects caused, however, the local incidence for at least 20 minutes could trigger some reaction. Due to the lack of studies investigating the action of the LED, and its irradiation time capable of triggering the reaction, it is common sense to contraindicate tooth whitening in patients being treated with Roacutan. The minimum time after the end of treatment should be 1 month, the time it takes for the medicine to be completely eliminated from the body.
Note: – There are many studies in the literature that use isotretinoin for the treatment of photodanified skin. – Most of the work related to dentistry studies the teratogenic effects of isotretinoin on dental formation, palate and so on. – I did not find any work that directly relates tooth whitening to the use of isotretinoin.

No. Composite resins are made up of monomers and vitreous fillers, but it is these vitreous particles that influence photoactivation time due to the different mechanisms of interaction with light emitted by the curing light. Nanoparticulate and microparticulate resins require a longer activation time (40s) than hybrid and microhybrid resins (20s).

Yes. Higher opacity makes it difficult to penetrate light energy at depth, so longer photoactivation time or high light intensity is essential for proper Light Curing. Dentin or opaque colors usually require 40s of photoactivation, while enamel colors usually 20s.

Light intensity can be understood as the amount of photons (unit of light energy) that is measured at the optical tip of the curing light. The optical power generated by the device is given in milliWatt. The more power – photons (mW) per unit area (cm²) is emitted through the fiber optic tip, the greater will be its light intensity or irradiance (mW / cm²).

Undoubtedly, the intensity of light is important, but just as important as this is the quality of the light energy emitted by the device. The quality of the blue light beam is essential for resinous materials to achieve their ideal properties at the end of light curing.

The quality of light is related to the wavelengths (nanometers – nm) emitted by the curing light, which will determine the blue tone of the light beam. Hardening of a material only occurs if light from the device is absorbed by photoinitiating substances present in adhesives, resins and cements. By absorbing blue light, photoinitiators will generate the free radicals that will initiate the polymerization process. Therefore, the higher the purity of the generated blue light (quality), the more efficient light curing becomes.
It is important to mention that although the vast majority of resins and cements use a photoinitiator called camphorquinone, which has the absorption peak at 470 nm (nanometers), there are some other types of photoinitiators that have lower absorption peaks (between 415 and 425). nm). Only a few light curing units using LED technology are capable of curing these resins and cements, and are expensive, imported appliances.