Comparison of the Effectiveness of CO2 and Diode Lasers for Gingival Melanin Depigmentation: A Randomized Clinical Trial.

Introduction: Gingival hyperpigmentation is an esthetic concern for some individuals. This study compared the effectiveness of CO2 and diode lasers for gingival depigmentation. Methods: This randomized, split-mouth, clinical trial consisted of 12 patients with the chief complaint of hyperpigmented gingival areas. The upper right and left anterior segments and the mandibular anterior segment were randomly allocated to one of the treatment groups. The segments in group 1 underwent gingival depigmentation with a diode laser (810 nm) at 6 W and pulsed mode, whereas group 2 was ablated with a diode laser at 3 W and continuous mode. The removal of gingival pigments in group 3 was contemplated with a CO2 laser (10600 nm, 3 W, continuous mode). The operation chair time, bleeding during the procedure and post-operative pain were recorded. The gingival color and esthetic appearance were measured before the operation and at 1 week and 6 months later. Results: There was no significant difference in the bleeding scores, pain level, and color alteration values between the groups (P>0.05). The operation chair time was significantly shorter when the diode laser was applied at pulsed mode (P<0.05). The segments treated with the diode laser (pulsed or continuous mode) showed a higher esthetic appearance at the 6-month follow-up compared to those ablated with the CO2 laser (P<0.05). Conclusions: Higher esthetic appearance is expected when using the diode laser for gingival depigmentation compared to the CO2 laser. The application of the diode laser at pulsed mode could be recommended for gingival depigmentation, as it produced pleasing esthetic outcomes at reduced chair time.

Effectiveness of an 810-nm Diode Laser in Addition to Non-surgical Periodontal Therapy in Patients With Chronic Periodontitis: A Randomized Single-Blind Clinical Trial.

Introduction: This study evaluated the effectiveness of an 810-nm diode laser as an adjunct to scaling and root planning (SRP) in improving periodontal parameters in patients with chronic periodontitis. Methods: This randomized clinical trial consisted of 36 patients (16 females and 20 males) with chronic periodontitis and pocket depths of 4-6 mm. The quadrants were randomly divided into two sides; one side of each patient was selected as the laser group (SRP + laser) and the other side served as the control group (SRP alone). An 810-nm diode laser was applied in the laser side to remove the outer gingival epithelium (1.5 W, CW) as well as the inner epithelium of the periodontal pockets (1 W, CW). The clinical parameters including bleeding on probing (BOP), probing depth (PD), plaque index (PI), and clinical attachment level (CAL) were measured at baseline and 6 and 18 weeks after therapy. Results: In both groups, there was a significant improvement in BOP, PD, PI and CAL over the course of the experiment (P < 0.001). Significantly lower BOP was found in the SRP + laser group than the SRP alone group after 6 and 18 weeks of intervention (P < 0.05). The difference in other parameters was not significant between the two groups, neither at 6 nor at 18 weeks after the treatment (P > 0.05). Conclusion: Within the limitations of this study, the association of the diode laser with standard non-surgical periodontal therapy (SRP) provided minimal additional benefits for patients with moderate chronic periodontitis.

Low level laser therapy, Er,Cr:YSGG laser and fluoride varnish for treatment of dentin hypersensitivity after periodontal surgery: A randomized clinical trial.

This clinical trial aimed to compare the effects of low-level laser therapy (LLLT), Er,Cr;YSGG laser, and fluoride varnish, as compared to the placebo laser on decreasing dentin hypersensitivity (DH). This randomized, double-blinded clinical trial included 60 jaw quadrants in 24 patients who underwent periodontal surgery. The quadrants were randomly assigned to 4 groups and received treatments as follows. Group 1: LLLT with a combination of red and infrared wavelengths, group 2: Er,Cr:YSGG laser (0.25 W and 0.5 W), group 3: fluoride varnish, and group 4: placebo laser. The sensitivity response to the cold spray was recorded using visual analogue scale (VAS) at baseline, immediately, and 1 week post-treatment. The data were analyzed by repeated measures analysis at the significance level of P<0.05. There was a significant reduction in DH after treatment by low-level lasers, Er,Cr:YSGG laser, or fluoride varnish compared to the baseline data (P<0.05), but the placebo group displayed no significant alteration in DH (P=0.069). At 1 week, the VAS score in the Er,Cr:YSGG laser group was significantly lower than that of the LLLT (P= 0.043) and placebo (P<0.001) groups. Furthermore, the subjects who received fluoride varnish exhibited significantly lower DH compared with the placebo group (P = 0.023). Er,Cr:YSGG laser was the most effective strategy in dealing with DH, as it caused the greatest pain reduction over the study period and showed a significant superiority over LLLT and placebo groups. Alternatively, the application of fluoride varnish could be recommended for attenuating DH following periodontal surgery.

The validity of laser fluorescence (LF) and near-infrared reflection (NIRR) in detecting early proximal cavities.

OBJECTIVES: Diagnosing cavitated proximal lesions is important for therapeutic decisions. This clinical study aimed to determine the validity of laser fluorescence (LF) and near-infrared reflection (NIRR) techniques for detecting early proximal cavities. MATERIALS AND METHODS: The study included 43 proximal surfaces in 15 females who had limited radiolucent lesions in their bitewing radiographs. The approximal areas of interest were assessed by DIAGNOdent Pen (LF) and the Proxi interchangeable head of VistaCam iX intraoral camera (NIRR). Finally, orthodontic separators were placed in the contact points to provide enough space between the teeth. The sensitivity, specificity, and accuracy of diagnosing cavitated proximal surfaces were calculated for LF and NIRR against direct visual and tactile examination as the reference standard. RESULTS: On the basis of the reference standard, 34 surfaces (79.1%) were not cavitated, whereas 9 surfaces (20.9%) were cavitated and in need of restoration. The sensitivity, specificity, and accuracy of LF were 44.4%, 61.8%, and 58%, and those of NIRR were 88.9%, 14.7%, and 30%, respectively. CONCLUSIONS: The VistaCam iX Proxi was more sensitive and DIAGNOdent Pen was more specific in detection of proximal cavities. However, none of the techniques was accurate enough to be recommended as a sole approach for proximal caries detection. CLINICAL RELEVANCE: LF showed an overall superior diagnostic performance to NIRR for diagnosing proximal cavitation in permanent posterior teeth. Within the limitations of this study, neither VistaCam iX Proxi nor DIAGNOdent Pen could be considered a suitable device for diagnosing proximal cavities.

Effectiveness of Low-Level Laser Irradiation in Reducing Pain and Accelerating Socket Healing After Undisturbed Tooth Extraction.

Introduction: This study aimed to determine the effect of low-level laser therapy (LLLT) on reducing complications following tooth extraction. Methods: This randomized clinical trial consisted of 40 subjects who underwent lower molar extraction. The patients were randomly assigned to 4 groups. Group 1 was irradiated with a 660 nm laser (200 mW, 30 seconds radiation to lingual, buccal and occlusal surfaces of the socket, 6 J/area). In group 2, an 810 nm laser was applied similar to group 1. In group 3, a combination of 660 and 810 nm lasers was used. The patients in group 4 served as a placebo group. LLLT was performed after 0.5-1 hour of extraction and 2 days later. The participants were asked to record pain degree using a visual analogue scale (VAS) over 7 days. The amount of wound healing was evaluated on the third and seventh days. Results: There was no significant difference in pain scores among the groups at any of the assessment intervals (P >0.05). The between-group differences in wound healing scores were small and insignificant (P >0.05). Conclusion: LLLT with 660 nm or 810 nm lasers or their combination had no greater effect than the placebo laser for reducing the complications of tooth extraction.

The efficacy and complications of several bleaching techniques in patients after fixed orthodontic therapy. A randomized clinical trial.

This study aimed to evaluate the efficacy and complications of several bleaching methods in patients with discolored teeth after orthodontic treatment. This randomized clinical trial involved 60 volunteers (31 women, 29 men) aged 14 to 30 years, who finished fixed orthodontic therapy at least three months before the study commencement and complained of discoloration on upper front teeth. The subjects were divided into four groups by treatment. The patients in group 1 received home bleaching, whereas those in groups 2 to 4 underwent in-office bleaching using a diode laser, a plasma arc and no light source, respectively. Tooth color was measured at baseline, one hour after the end of the bleaching procedure, and one week later, and the color alteration between different stages was compared among the groups. The severity of tooth sensitivity and the occurrence of other post-treatment complications were recorded. The color change between baseline and one week after treatment was greatest in the home-bleaching and the laser-assisted bleaching groups, and lowest in the plasma-arc bleaching group, although the difference between the groups was not significant (p > 0.05). Tooth sensitivity over 24 hours after bleaching was lowest in subjects who had undergone laser-assisted bleaching and highest in those who had received in-office bleaching without light (p < 0.05). All methods were effective in managing tooth discoloration after orthodontic treatment. Home bleaching produced favorable color alteration. Amongst the in-office approaches, laser-assisted bleaching should be considered as the best option, as it produced effective results with lowest tooth sensitivity and over a shorter period of time.

A randomized clinical trial comparing the efficacy of low-level laser therapy (LLLT) and laser acupuncture therapy (LAT) in patients with temporomandibular disorders.

This study compared the efficacy of low-level laser therapy (LLLT) versus laser acupuncture therapy (LAT) in patients with temporomandibular disorders (TMDs). In this randomized, double-blind clinical trial, 45 TMD patients were randomly divided into three groups. In group 1 (LLLT), a GaAlAs laser was applied on painful masticatory muscles and TMJs (810 nm, 200 mW, 30 s per point, Gaussian beam, spot size 0.28 cm2, 21 J/cm2) two times a week for 5 weeks. In group 2 (LAT), the laser was emitted bilaterally on acupuncture points (ST6, ST7, LI4) with the same settings as the LLLT group. Group 3 (placebo) underwent treatment with sham laser. The patients were evaluated before treatment (T1), after 5 (T2) and 10 (T3) laser applications, and 1 month later (T4). The mandibular range of motion as well as pain intensity in masticatory system was recorded at each interval. There was no significant difference in mouth opening between the groups (p > 0.05), but the amount of lateral excursive and protrusive movements was significantly greater in LLLT and LAT groups than the placebo group at some intervals (p < 0.05). The overall pain intensity and pain degree at masticatory muscles (except temporal muscle) and TMJs were significantly lower in both experimental groups than the placebo group at most intervals after therapy (p < 0.05). Both LLLT and LAT were effective in reducing pain and increasing excursive and protrusive mandibular motion in TMD patients. LAT could be suggested as a suitable alternative to LLLT, as it provided effective results while taking less chair time.

Mineral trioxide aggregate and portland cement for direct pulp capping in dog: a histopathological evaluation.

Background and aims. Mineral trioxide aggregate and calcium hydroxide are considered the gold standard pulp-capping materials. Recently, Portland cement has been introduced with properties similar to those of mineral trioxide aggregate. Histopathological effects of direct pulp capping using mineral trioxide aggregate and Portland cements on dog dental pulp tissue were evaluated in the present study. Materials and methods. This histopatological study was carried out on 64 dog premolars. First, the pulp was exposed with a sterile bur. Then, the exposed pulp was capped with white or gray mineral trioxide aggregates and white or gray Portland cements in each quadrant and sealed with glass-ionomer. The specimens were evaluated under a light microscope after 6 months. Statistical analysis was carried out using Kruskal-Wallis test. Statistical significance was defined at α=5%. Results. There was no acute inflammation in any of the specimens. Chronic inflammation in white and gray mineral trioxide aggregates and white and gray Portland cements was reported to be 45.5%, 27.3%, 57.1% and 34.1%, respectively. Although the differences were not statistically significant, severe inflammation was observed mostly adjacent to white mineral trioxide aggregate. The largest extent of increased vascularization (45%) and the least increase in fibrous tissue were observed adjacent to white mineral trioxide aggregate, with no significant differences. In addition, the least calcified tissue formed adjacent to white mineral trioxide aggregate, although the difference was not significant. Conclusion. The materials used in this study were equally effective as pulp protection materials following direct pulp capping in dog teeth.