Photobiomodulation, Transmucosal Laser Irradiation of Blood, or B complex as alternatives to treat Covid-19 Related Long-Term Taste Impairment: double-blind randomized clinical trial.

COVID-19 Related Long-Term Taste Impairment (CRLTTI) is a condition that can be expressed after COVID-19 contagion, lasting for months or even years, affecting the routine and quality of life of individuals. Participants expressing CRLTTI, with a minimum of 2 months, attested by PCR-RT test were assessed for taste and smell, and underwent experimental treatments in 6 distinct groups: Photobiomodulation (PBM) in tongue dorsum and lateral (660 nm, 808 nm, association of 660 and 808 nm), Transmucosal Laser Irradiation of Blood (TLIB)-ventral surface of tongue (660 nm), B complex supplementation, and Sham laser. No intergroup statistical differences were observed at the final evaluation, despite the tendencies of better results with PBM and TLIB observed. PBM, TLIB, and B complex might be treatment options in the management of CRLTTI, despite the lack of total remission of taste and smell perception after 8 sessions (PBM and TLIB) or 30 days of B complex supplementation.

Photobiomodulation Therapy on the Palliative Care of Temporomandibular Disorder and Orofacial/Cervical Skull Pain: Preliminary Results from a Randomized Controlled Clinical Trial.

The main symptoms of temporomandibular disorders (TMDs) are pain from musculoskeletal and/or joint-in the head and neck region-and complaints of difficulty in mandibular movements. The photobiomodulation therapy (PBMT) has been reported as a promising treatment in the management of these symptoms. The objective of this research was to assess the effect of PBMT immediately after irradiation on TMDs symptoms under a prospective clinical trial, randomized, triple-blinded, placebo-controlled, and with two parallel arms. According to the RDC/TMD, maximum mouth opening (MMO) and pain in the orofacial/cervical muscles and temporomandibular joint (TMJ) were recorded. One hundred forty-five participants (71 placebo and 74 PBMT experimental) were analyzed after irradiation protocols (sham-PBMT or PBMT) at the orofacial/cervical skull musculature and at the TMJ. The results showed a reduction in the total pain score (p = 0.026), a reduction in the number of painful points (p = 0.013), and an increase in the MMO (p = 0.016) in the PBMT protocol group when compared to the placebo protocol (sham-PBMT). The PBMT was shown to be effective in reducing orofacial/cervical skull pain immediately after the irradiation. It is clinically relevant and should be taken into consideration by professionals who are dedicated to treating this pathology because, in addition to bringing comfort to patients who need dental treatment, it also consists of a low-cost and low technical complexity clinical approach.

In vitro effectiveness of different dental bleaching protocols using violet LED.

PURPOSE: There has been growing demand for dental bleaching worldwide, however, despite being effective, hydrogen peroxide (HP) can negatively affect the dental structure. Thus, new techniques, such as violet LED light have emerged and need to be studied. The aim of this study was to analyze and compare the effectiveness of violet LED light alone or combined with 35% HP gel. METHODS: Six different tooth bleaching techniques (n = 10) were performed in intrinsically pigmented bovine teeth: G1 - 35% HP (1x/week for 4 weeks, 45 min of gel application); G2 - 35% HP (1x/week for 4 weeks, 15 min of gel application); G3 - violet LED (1x/week for 4 weeks); G4 - violet LED (2x/week for 2 weeks); G5 - violet LED (4x/week for 1 week); G6 - Violet LED + 35% HP (hybrid technique, 1x/week for 4 weeks, 15 min of gel application). Specimens were submitted to color evaluation at predetermined times using Konica Minolta® spectrophotometer, and the surface morphology (n = 3) was qualitatively analyzed by Scanning Electron Microscope (SEM). Data of the color change test were analyzed considering a 5% level of significance. RESULTS: There was significant difference in color (p <0.05) for all groups after bleaching protocols. SEM analysis revealed that the greatest change in surface occurred in Group G1, with demineralization of the dental enamel. When considering the same time interval, there were no statistical differences for axis L*, but differences were shown for axis a* (G2, G3, G4 ≥ G1, G5 ≥ G6) and b* (G1, G2, G3, G4, G5 > G6). Regarding the comparison of ΔE00 between groups, results showed statistical difference between groups, with G1 ≥ G2, G5, G6 ≥ G3, G4. CONCLUSION: Bleaching protocols with less time (15 min) or no exposure to 35% HP (violet LED, 4x/week) could promote bleaching results as those obtained by the conventional technique using 35% HP for 45 min, with no enamel surface changes, showing to be a promising alternative to tooth bleaching.

Influence of Er:YAG laser irradiation settings on dentin-adhesive interfacial ultramorphology and dentin bond strength.

This study evaluated the effects of Erbium-doped yttrium aluminium garnet (Er:YAG) laser settings and dentin bonding agents on ultramorphological characteristics of resin-laser-irradiated dentin interfaces and dentin bond strength (BS) of these adhesive systems. Additionally, dentin depth affected by Er:YAG laser irradiations was measured. The experiments were performed on occlusal dentin surfaces of third molars that were flattened with 600-grit SiC sandpaper. Treated-dentin with laser settings (250 mJ/4 Hz and 160 mJ/10 Hz) were the experimental groups, while SiC abraded dentin was the control. These three dentin treatments and three adhesives (two self-etchings and one etch-&-rinse adhesive) formed nine groups for the ultramorphology of laser-ablated dentin-adhesives interfacial analysis, using a transmission electron microscope (TEM). For BS (n = 8), the same nine groups were tested with addition of the two evaluation times (24 h after sample preparation or 1 year). The depths of Er:YAG laser effects into the dentin were measured using a TEM (n = 10). Ablated-dentin depth and BS data were analyzed by one- and three-way ANOVA, respectively, and Tukey's test (α = 0.05). Hybrid layer formation was only observed for controls, while for laser-treated dentin, adhesives were bonded to dentin with resin tags formation. Laser settings reduced the BS for all adhesives at 24 h, while at 1 year, etch-&-rinse adhesive presented the highest BS, regardless treatment (control or laser settings). Dentin depth affected by laser settings was similar. The laser irradiation altered the bonding mechanism of the adhesives to dentin and reduced the BS for self-etching adhesives. Etch-&-rinse adhesive yielded the highest BS at 1 year. Laser settings similarly affected the dentin in depth. HIGHLIGHTS: Er:YAG laser irradiation settings produced similar effects on depth and bond strength to dentin. The etch-&-rinse adhesive yielded the highest dentin bond strength regardless of the type of dentin treatment at 1 year.

Effect of CO2 laser combined with AmF/NaF/SnCl2 solution on the prevention of human and bovine enamel erosion.

This in vitro study evaluated the potential of CO2 laser (10.6 µm) combined with a stannous/fluoride-containing solution for preventing erosion in human/bovine enamel. Forty-eight samples of each substrate were randomly allocated to four groups (n = 12): W - distilled water; E - AmF/NaF/SnCl2 solution; L - CO2 laser; and LE - CO2 laser+AmF/NaF/SnCl2 solution. After surface treatments, samples were submitted to a 5-day erosive challenge, alternating immersions in 0.5% citric acid (2 minutes, 6x/day) and in artificial saliva. Optical profilometry (µm) and scanning electron microscopy (SEM) were used to determine surface loss and surface morphology, respectively. Data were statistically analyzed by two-way ANOVA and Tukey's tests (p < 0.05). For human enamel, tissue loss was lower in group L (12.37 ± 4.46) than in group W (16.45 ± 2.76), and higher than in the groups treated with AmF/NaF/SnCl2 solution (E-5.44 ± 2.37; LE-5.55 ± 2.31). In group L, SEM images reveled a disorganized surface but fewer projections than in group W and LE showed fewer irregularities than W, E, and L. For bovine enamel, tissue loss in group L (13.90 ± 3.50) did not differ from that in group W (14.10 ± 2.98), and was higher than losses in groups E (5.70 ± 2.12) and LE (8.12 ± 2.56), which were statistically similar to each other. Groups W and L had similar aspects of demineralization, whereas groups E and LE showed homogenous surfaces. Surface-treated samples had no changes in their surfaces. CO2 laser was able to slightly prevent surface loss only on human enamel surface, but did not enhance the AmF/NaF/SnCl2 effect on the prevention of enamel erosion.

The Influence of Different Bleaching Protocols on Dentinal Enzymatic Activity: An In Vitro Study.

This study aimed to investigate matrix metalloproteinase (MMP) activity in human dentin using in-situ and gelatin zymography, after at-home and in-office bleaching, related to their clinical exposure times. Dentin specimens (n = 5) were treated with 35% hydrogen peroxide (50 min per session/4 sessions), 10% carbamide peroxide (180 min/21 sessions), or no treatment. All were subjected to in-situ zymography. Dentin slices were, subsequently, obtained, covered with fluorescein-conjugated gelatin, and examined with confocal laser-scanning microscopy. The fluorescence intensity was quantified and statistically analyzed using one-way ANOVA and Bonferroni tests (α = 0.05). Furthermore, gelatin zymography was performed on protein extracts obtained from dentin powder (N = 8 teeth), treated with hydrogen peroxide or carbamide peroxide, with different exposure times (10/50 min for hydrogen peroxide; 252/1260 min for carbamide peroxide). The results of the in-situ zymography showed no statistical differences between the bleached specimens and the control group, with a medium level of gelatinolytic activity expressed in the dentin tubules. The results of gelatin zymography showed an increased expression of pro-MMP-9 in carbamide peroxide groups. The expression of pro-MMP-2 decreased in all the experimental groups. The bleaching treatments performed on the enamel of sound teeth do not influence dentinal enzymatic activity. However, when unprotected dentin tissue is bleached, matrix metalloproteinases are more expressed, particularly when carbamide peroxide is used, proportional to the exposure time.

Blinded, parallel and randomized clinical evaluation of in-office dental bleaching with violet LED (405-410nm).

This clinical study evaluated the effect of bleaching performed with violet LED light (405-410 nm), either combined with hydrogen peroxide (HP) gel, or not, on color change, dental sensitivity, participants' satisfaction and impact on their quality of life. A hundred participants were divided into one of the groups (n = 25): G1 - 35% HP (4 sessions, 1x/week); G2 - violet LED (4 sessions, 1x/week); G3 - violet LED (4 sessions, 2x/week); G4 - hybrid technique (violet LED + 35% HP; 4 sessions, 1x/week). Color evaluation was performed with colorimetric tests (objective and subjective), before, 14 days and 3 months after completion. Additionally, satisfaction with treatment, impact on quality of life (OHIP-14) and dental sensitivity were recorded. The data were submitted to statistical analysis, considering a significance level of 5%, with the exception of the data from the questionnaire on satisfaction (descriptive analysis). Two-way ANOVA and Tukey tests showed that there was no difference between color variation resulting from techniques used in G1 and G4; those used in G2 and G3 did not differ and were less effective for bleaching than those of the other groups, in both subjective and objective evaluations. Regarding tooth sensitivity, subjects in G2 and G3 experienced no sensitivity, ​​while those in G4 showed lower sensitivity values than those in G1. With respect to quality of life, only subjects in G1 and G2 showed a significant positive impact. Among the evaluated techniques, the hybrid type seemed to be a good alternative, showing effective bleaching with less tooth sensitivity.

Effect of CO2 laser combined with AmF/NaF/SnCl2 solution on the prevention of human and bovine enamel erosion

Abstract: This in vitro study evaluated the potential of CO2 laser (10.6 μm) combined with a stannous/fluoride-containing solution for preventing erosion in human/bovine enamel. Forty-eight samples of each substrate were randomly allocated to four groups (n = 12): W - distilled water; E - AmF/NaF/SnCl2 solution; L - CO2 laser; and LE - CO2 laser+AmF/NaF/SnCl2 solution. After surface treatments, samples were submitted to a 5-day erosive challenge, alternating immersions in 0.5% citric acid (2 minutes, 6x/day) and in artificial saliva. Optical profilometry (μm) and scanning electron microscopy (SEM) were used to determine surface loss and surface morphology, respectively. Data were statistically analyzed by two-way ANOVA and Tukey's tests (p < 0.05). For human enamel, tissue loss was lower in group L (12.37 ± 4.46) than in group W (16.45 ± 2.76), and higher than in the groups treated with AmF/NaF/SnCl2 solution (E-5.44 ± 2.37; LE-5.55 ± 2.31). In group L, SEM images reveled a disorganized surface but fewer projections than in group W and LE showed fewer irregularities than W, E, and L. For bovine enamel, tissue loss in group L (13.90 ± 3.50) did not differ from that in group W (14.10 ± 2.98), and was higher than losses in groups E (5.70 ± 2.12) and LE (8.12 ± 2.56), which were statistically similar to each other. Groups W and L had similar aspects of demineralization, whereas groups E and LE showed homogenous surfaces. Surface-treated samples had no changes in their surfaces. CO2 laser was able to slightly prevent surface loss only on human enamel surface, but did not enhance the AmF/NaF/SnCl2 effect on the prevention of enamel erosion.

Effectiveness of Laser Therapy and Laser Acupuncture on Treating Paraesthesia After Extraction of Lower Third Molars.

Objective: This randomized clinical trial evaluated the sensitive return of the lower alveolar nerve (LAN) using two photobiomodulation therapy (PBMT) techniques, after the extraction of lower third molars or implant surgery. Materials and methods: Sixty participants with sensory impairment of LAN were randomly divided into three groups (n = 20): group C-systemic medication (control-ETNA®, 01 capsule, 8/8 h, 30 days); group laser therapy (LT) (808 nm, 100 mW, 40 sec/point, 4 J/point, intra/extraoral, irradiation following nerve path); group laser acupuncture (LA) (same parameters as the LT group, applied at six acupuncture points on the affected side (ST 4 [Dicang], M-HN-18 [Jiachengjiang], CV 24 [Chengjiang], ST 5 [Daying], ST 6 [Jiache], and point A1 [YNSA]). The following evaluations were performed, at predetermined times: general perception of paresthesia, thermal perception, vibratory mechanical perception, two-point discrimination, pain perception, and tactile perception. Data were analyzed by two-way analysis of variance (ANOVA), followed by the Tukey, except for the two-point discrimination, which was analyzed using the chi-square test. Results: In general and thermal perception, both PBMTs had better results than control; regarding cold perception, only the LT group was statistically superior to control. LA presented inferior results of neural regeneration for tests of perception of pain and tactile at the lip, and of tactile perception at the chin. In the other tests, there was no statistical difference among the groups. Conclusions: LT and the conventional drug treatment had the same effectiveness and both were superior to LA for the treatment of paresthesia of the LAN after oral surgeries.

In situ Effect of CO2 Laser (9.3 µm) Irradiation Combined with AmF/NaF/SnCl2 Solution in Prevention and Control of Erosive Tooth Wear in Human Enamel.

OBJECTIVES: This single-blind, controlled crossover in situ study aimed to evaluate the effect of CO2 laser (9.3 µm) irradiation combined with AmF/NaF/SnCl2 solution on prevention and control of erosive tooth wear (ETW) in human enamel. MATERIALS AND METHODS: Two trial conditions were analyzed, condition 1 as ETW prevention (sound tooth surface) and condition 2 as ETW control (in vitro initial erosive lesion). The experiment was conducted in 2 phases, one with and one without exposure to AmF/NaF/SnCl2 solution. Hundred and ninety-two samples of human enamel (3 × 3 × 1 mm) were randomly divided into 4 experimental groups for each condition: C, without treatment (negative control); F, AmF/NaF/SnCl2 solution (positive control); L, CO2 laser irradiation; and L + F, CO2 laser + AmF/NaF/SnCl2 solution. Twelve volunteers used a removable device, each containing 8 samples per phase. Ex vivo erosive challenges (4 × 5 min/day) and rinsing protocol (1 × 30 s/day) were performed. The surface loss was determined using optical profilometer (n = 12 per group), and the surface morphology was observed with scanning electron microscopy (n = 3). RESULTS: In condition 1, data were analyzed by one-way ANOVA and condition 2 by two-way repeated-measures ANOVA, both with Tukey post hoc tests (α = 5%). In condition 1, groups L (4.59 ± 2.95 µm) and L + F (1.58 ± 1.24 µm) showed significantly less surface loss in preventing ETW than groups C and F. In condition 2, in controlling the progression of ETW, L + F was the only group with no significant surface loss between initial erosive lesion (3.65 ± 0.16 µm) and after erosive challenge (4.99 ± 1.17 µm). CONCLUSIONS: CO2 9.3-µm laser application prevented and controlled ETW progression in human enamel, with greater efficiency when combined with AmF/NaF/SnCl2 solution application.

Influence of 35% hydrogen peroxide gel renewal on color change during in-office dental photobleaching with violet LED: A split-mouth randomized controlled clinical trial.

BACKGROUND: To clinically evaluate the effect of 35% hydrogen peroxide gel renewal in association with violet LED (405-410nm) through a split-mouth randomized controlled clinical trial. METHODS: The treatment consisted in 3 bleaching sessions of 15 min each, with an interval of 7 days between them, using 35% hydrogen peroxide combined to violet LED irradiation. Selected patients had two experimental segments for the split-mouth design: No change of the bleaching gel during each session (NBGR) and 3 changes of the bleaching gel every 5 min for each session (BGR). During the 3 bleaching sessions, the selected quadrant received the same treatment. Patients had their upper canines and central incisors teeth color measured with a subjective (color scale - VITA Classical) and an objective (spectrophotometer - VITA Easyshade) method and their teeth sensitivity measured using a Visual Analog Scale (VAS) before, immediately after each bleaching session, and 14 days and 2 months (60 days) after the end of the treatment. RESULTS: The protocol adopted in the present study reached satisfactory results regarding color change. No statistical difference between groups was observed immediately after the end of the treatment and in the follow-up analysis for both subjective and objective color evaluation. No difference in tooth sensitivity between segments was observed. CONCLUSION: There is no need for bleaching gel renewal when following the clinical protocol of 3 sessions of 15 min in a bleaching protocol of 35% hydrogen peroxide combined with violet LED.

In-office bleaching protocols using violet LED: A split mouth case report.

A new LED wavelength, violet LED (VL) with a wavelength between 405 - 410 nm was recently introduced to be used for in-office dental bleaching. In comparison to the blue LED system (440 to 485 nm), the shorter wavelength has more energy carried in its photons and also corresponds to the absorption peak of the stained particles, which lead to whitening utilizing a physical process. Considering the need to suggest and develop new protocols with this new technology, this article reports 2 different dental bleaching protocols developed in a split-mouth model using VL. A 25-year-old male patient was submitted to in-office dental bleaching. On the teeth from the left side, the bleaching gel (35% H2O2) was renewed 3 times (every 8 mins), and on the right side, the gel was maintained without renewal during the bleaching session. The irradiation with Violet LED Light (405 nm ± 10 nm) was performed with the following protocol: 1 min of irradiation with 30 s light off until 8 min of total time. A total of 3 cycles were performed (total time of 24 min). Two bleaching sessions were performed with an interval of 7 days between sessions. Based on the results of this split-mouth case report, there was no visible difference in the final color outcome and sensitivity between both bleaching protocols tested.

Effect of TiF4 varnish after pre-treatment with proanthocyanidin or chlorhexidine on the progression of erosive dentin loss in the presence or absence of the demineralized organic matrix.

This study evaluated the protective effect of TiF4 varnish, after pre-treatment with proantocyanidin or chlorhexidine, on the progression of erosive dentin loss (EDL), under the presence or absence of the demineralized organic matrix (DOM). Bovine root dentin samples were eroded for 30 min (0.1% citric acid, pH 2.5) and the loss was measured by profilometry. Half of them were subjected to the DOM removal using collagenase for 4 days, while the other half remained immersed in water. The removal of DOM was checked by profilometry. Samples were divided into 24 groups (n = 15) according to the factors: 1- With or without DOM; 2- Pre-treatment with 0.012% chlorhexidine gel, 10% proanthocyanidin gel or untreated for 1 min; 3-Final Treatment with TiF4 varnish, NaF varnish, placebo varnish or untreated for 6 h. The samples were submitted to a pH cycling for 5 days: 0.1% citric acid (4 × 90s/day) and artificial saliva between the challenges. The final profile was obtained for the calculation of EDL (µm, three-way ANOVA/Tukey test). When DOM was preserved, the EDL was lower compared to the condition without DOM (7.08 ± 4.03 µm and 9.80 ± 3.79 µm, p < 0.001, respectively), regardless of the treatments. The pre-treatment had no influence on the progression of EDL (p = 0.637), while the final treatment (TiF4 varnish only, 6.77 ± 4.08 µm) was effective in reducing the progression of EDL (NaF varnish: 9.52 ± 4.02 µm; Placebo varnish: 8.64 ± 4.06 µm and no treatment: 8.80 ± 3.95 µm). It can be concluded that DOM has important protective effect on the progression of EDL. TiF4 was the unique treatment capable of reducing EDL progression, regardless of the pre-treatment of DOM.

Influence of biosafety materials of the laser output power.

Biosafety materials used in the correct handling of low power laser equipment may interfere on the power delivered at the target tissue and, possibly, on the effects on biological tissues. The aim of this study was to evaluate the interference of the use of polyvinyl chloride (PVC) and polyethylene (PEAD) protection materials on the output power of low power lasers. Two low power diode laser devices with different wavelengths (red and infrared) were used. For each wavelength, two protection materials and two evaluation times (before and after protection) were considered. The output power (mW) was measured with the tip positioned in close contact with the power meter receiver. Parametric statistical test, two-way ANOVA for repeated measures (protection material and time), was performed considering the level of significance of 5%. In respect to "time", all groups had the output power reduced after placing the protective material (p < 0.05). Comparing the protection materials, the PEAD showed a greater reduction in output power than the PVC for both red and infrared wavelengths. It was concluded that, among the biosafety materials tested, PVC is the most suitable for the protection of the tip of the low power lasers.

Influence of Er:YAG laser surface treatment on flexural and bond strengths to glass-infiltrated zirconia-reinforced ceramic.

To evaluate the effect of Er:YAG laser conditioning of a glass-infiltrated alumina-based zirconia-reinforced ceramic on its flexural strength and on bonding to a resin cement. Sixteen blocks (5 × 5 × 4 mm) and 50 discs (Ø 12 mm, 1 mm thickness) of In-Ceram Zirconia (ICZ) obtained from CAD-CAM blocks were infiltrated with glass. For the microtensile bond strength (µTBS) test, all blocks were treated with aluminum oxide (AOX) and divided into 4 groups (n = 4): G1 (AOX), no combined surface treatment; G2 (ROC), tribochemical silica-coating; G3 (EY200), Er:YAG laser 200 mJ/15 Hz; and G4 (EY250), Er:YAG laser 250 mJ/10 Hz. The ceramic blocks were silanated and cemented with a resin cement (Panavia F2.0/Kuraray) to composite resin blocks and subjected to the µTBS test. For the flexural strength evaluation, the discs were divided into 5 groups (n = 10) as described above, in addition to a control group (G5 - CTRL, mirror-polished without further treatment). Each surface treatment was submitted to qualitative evaluation under SEM. One-way ANOVA (α = 5%) revealed the highest bond strength value for EY200 with no significant difference from ROC. The groups AOX and EY250 showed similar µTBS values that were statistically lower than those of EY200. For flexural strength, ROC was the only group with significantly lower values when compared with the CTRL. The use of Er:YAG laser at 200 mJ/15 Hz can be considered an innovative and effective alternative for surface conditioning of ICZ since it did not reduce the flexural strength of the ceramic and improved the resin cement bond to this substrate.

Monitoring enamel caries on resin-treated occlusal surfaces using quantitative light-induced fluorescence: an in vitro study.

The aim of this study is to evaluate the ability of quantitative light-induced fluorescence (QLF) to monitor enamel caries lesions of different severity stages located on the occlusal surfaces of permanent teeth before and after treatment with resin infiltrant. Sixty extracted permanent teeth had one occlusal site selected and were categorized according to the International Caries Detection and Assessment System (ICDAS) criteria. The teeth were divided into three groups (n = 20): ICDAS 1, ICDAS 2, and ICDAS 3. The teeth were assessed by a trained examiner using QLF in two phases: (A) before and (B) after treatment with resin infiltrant. The caries lesions were evaluated using the following QLF parameters: area (mm2); ΔF, fluorescence loss (%); and ΔQ, fluorescence loss integrated over the lesion area (%*mm2). The resin infiltrant (Icon™) was applied on the occlusal surface following the manufacturer's recommendations. The teeth were then sectioned and prepared for polarized light microscopy analysis. The penetration of resin infiltrant was measured with ImageJ. The groups showed a statistically significant difference in all QLF parameters before and after caries infiltration, with the reduction of fluorescence values posttreatment (p < 0.05). Infiltrant penetration was observed in all groups, with a statistical difference between all groups (p < 0.05). The reduction in QLF parameters after resin infiltration suggests that QLF is able to monitor enamel caries lesions of different severity stages located on the occlusal surfaces of permanent teeth before and after treatment with resin infiltrant.

Effect of gel replacement during in-office dental bleaching: a case report.

In-office dental bleaching allows the dentist to have greater control of the procedure and prevents patients from ingesting chemicals. To obtain optimum results, in-office bleaching usually requires a longer period of application as well as changes of the bleaching agent applied to the tooth surfaces at each appointment. The objective of this case report was to assess, by means of a split-mouth design in a single patient, the final tooth color and tooth sensitivity resulting from 2 different bleaching protocols: 1 application of 35% hydrogen peroxide for 45 minutes and 3 applications of 35% hydrogen peroxide for 15 minutes each. Neither the patient nor 5 individuals who were blinded to the techniques noted a difference in the final esthetic results of the 2 protocols immediately after the procedure. In addition, the patient reported that no tooth sensitivity was associated with either protocol. The results of dental bleaching on both sides were maintained after 15 days. The results shown in the present case report suggest that there may be no need to renew the gel during in-office dental bleaching.

Associative Protocol for Dentin Hypersensitivity Using Nd:YAG Laser and Desensitizing Agent in Teeth with Molar-Incisor Hypomineralization.

Objective: The aim of this article was to describe and discuss a clinical case in which the Nd:YAG laser and a desensitizing agent were associated in a protocol for dentin hypersensitivity (DH) in teeth with molar-incisor hypomineralization (MIH). Background data: DH is a common condition among the population, being one of the main reasons for patients to seek for a dental treatment. MIH can be considered a condition that induces DH. Methods: The patient was referred for evaluation, complaining of hypersensitivity during eating or drinking cold foods. Clinical evaluation revealed the presence of MIH on the first lower molars. Aiming to treat DH, two strategies for dentin desensitization were associated: the use of a high-power laser (Nd:YAG laser, 1.064 nm; Lares Research), with a 300 µm quartz optical fiber, 1 W of power, 100 mJ of energy, 10 Hz of repetition rate, and 85 J/cm2 of energy density, followed by the application of two layers of a desensitizing agent (Gluma Desensitizer). Results: DH was evaluated immediately, after 1 week and after 1 month of the treatment. Clinical outcomes were satisfactory, confirming the efficacy and considerable durability of the protocol used for the reduction of DH originated from MIH. Conclusions: The association of Nd:YAG laser and a desensitizing agent for controlling DH was effective, showing to be an interesting protocol.

Photobiomodulation with Low-Level Laser in the Treatment of Trismus After Radiotherapy: A Case Report.

Background: Radiotherapy is one of the treatments for cancer, which leads to many oral side effects that affect the quality of life of the patient; among them, trismus is considered. Objective: Considering the various therapies to treat this collateral effect of radiotherapy, photobiomodulation (PBM) with low-level laser is a contemporary alternative. Methods: In this article, an all-clinical case report is presented in which the patient was given trismus after radiotherapy and PBM with low-level laser. The measurement of the buccal opening was evaluated in each treatment session with a digital caliper, and the pain was evaluated through the visual analog scale (VAS). Results: The efficacy of the PBM protocol on the trismus after radiotherapy was evidenced by the decrease of pain and increase of the buccal opening. Conclusions: The use of PBM with low-level laser is an option for the treatment of trimus after radiotherapy.