Juvenile Hyaline Fibromatosis Management With a Diode Laser: A Rare Case Report.

Juvenile hyaline fibromatosis (JHF) is an unknown hereditary disorder with variable penetrance. The characterizations of this disease consist of different signs and symptoms such as multiple tumorous (tumor-like) muco-cutaneous proliferation, gingival hypertrophy, perianal lesions, articular contractures, and osteolytic lesions. A 3-year-old girl with numerous painless nodular masses on her gingival, ear and anal areas is presented in this case report. Based on characteristic histological features, the diagnosis of JHF was made. The patient underwent surgery following general anesthesia and the above areas were surgically operated with appropriate laser parameters, and the patient was able to eat and wash away after a day and was discharged with an antibiotic prescription after one day in the hospital and returned to normal after a week. The recurrence occurred in other areas a year later, especially in the cheek, the ears and the anal area. Therefore, this rare case is presented with recurrence.

Evaluation of laser fluorescence in combination with photosensitizers for detection of demineralized lesions.

BACKGROUND AND OBJECTIVES: Early detection of caries plays an important role in its prognosis. This study sought to assess the efficacy of laser fluorescence alone and in combination with photosensitizers for detection of demineralized smooth-surface lesions of permanent teeth. MATERIALS AND METHODS: This in vitro experimental study was conducted on 60 extracted sound premolars. Four windows measuring 2 x 2 mm were created on each tooth. Forty out of 60 teeth were subjected to demineralization cycle. All teeth were then sectioned and subjected to DIAGNOdent Pen (Kavo, Biberach, Germany) alone and in combination with 0.2-mM tetrakis N-methylpyridyl porphyrin (TMPyP) fluorescent dye, 2% methylene blue and 2% new methylene blue photosensitizers. The results of histological analysis of sections served as the gold standard. The correlation of the results with the gold standard was assessed using the Pearson's correlation coefficient and receiver operating characteristic (ROC) curve. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of the four techniques were evaluated as well. RESULTS: The correlation between the results of DIAGNOdent laser with TMPyP dye and the gold standard was significant (P < 0.05). Also, this technique had the highest sensitivity while DIAGNOdent laser alone had the highest specificity. CONCLUSION: Laser fluorescence with TMPyP fluorescent dye has suitable efficacy for early detection of initial enamel lesions.

Transected sciatic nerve repair by diode laser protein soldering.

BACKGROUND AND OBJECTIVE: Despite advances in microsurgical techniques, repair of peripheral nerve injuries (PNI) is still a major challenge in regenerative medicine. The standard treatment for PNI includes suturing and anasthomosis of the transected nerve. The objective of this study was to compare neurorraphy (nerve repair) using standard suturingto diode laser protein soldering on the functional recovery of transected sciatic nerves. STUDY DESIGN/MATERIALS AND METHODS: Thirty adult male Fischer-344 Wistar rats were randomly assigned to 3 groups: 1. The control group, no repair, 2. the standard of care suture group, and 3. The laser/protein solder group. For all three groups, the sciatic nerve was transected and the repair was done immediately. For the suture repair group, 10.0 prolene suture was used and for the laser/protein solder group a diode laser (500mW output power) in combination with bovine serum albumen and indocyanine green dye was used. Behavioral assessment by sciatic functional index was done on all rats biweekly. At 12weeks post-surgery, EMG recordings were done on all the rats and the rats were euthanized for histological evaluation of the sciatic nerves. The one-way ANOVA test was used for statistical analysis. RESULTS: The average time required to perform the surgery was significantly shorter for the laser-assisted nerve repair group compared to the suture group. The EMG evaluation revealed no difference between the two groups. Based on the sciatic function index the laser group was significantly better than the suture group after 12weeks (p<0.05). Histopathologic evaluation indicated that the epineurium recovery was better in the laser group (p<0.05). There was no difference in the inflammation between the suture and laser groups. CONCLUSION: Based on this evidence, laser/protein nerve soldering is a more efficient and efficacious method for repair of nerve injury compared to neurorraphy using standard suturing methods.

Comparison of laser and power bleaching techniques in tooth color change.

BACKGROUND: Laser-assisted bleaching uses laser beam to accelerate release of free radicals within the bleaching gel to decrease time of whitening procedure. The aim of this study was to compare the efficacy of power bleaching using Opalescence Xtra Boost® and laser bleaching technique using LaserSmile gel and diode laser as an activator in their tooth whitening capacity. MATERIAL AND METHODS: Student t test showed that the laser bleaching group significantly outperformed the power bleaching group in changing ∆E (p=0.977). RESULTS: Similarly, while comparing the groups in changing ∆L, the laser bleaching group indicated significantly superior results (p=0.953). Statistical data from student t test while comparing the groups in changing the parameter of yellowness indicated that samples in laser bleaching group underwent a more significant reduction than power-bleached samples (p=0.85). Correspondingly, changes in whiteness were statistically tested through student t test, showing that laser bleaching technique increased whiteness of the samples significantly more than those treated by power bleaching (p=0.965). The digital color evaluation data was in accordance with spectrophotometry and showed that laser bleaching outperformed power bleaching technique. Both techniques were able to increase whiteness and decrease yellowness ratio of the samples. ΔE decrease for laser bleaching and power bleaching groups were 3.05 and 1.67, respectively. Tooth color change in laser bleaching group was 1.88 times more than that of power bleaching group (p<0.001). CONCLUSIONS: It could be concluded that under the conditions of this study, both laser-assisted and power bleaching techniques were capable of altering tooth color change, but laser bleaching was deemed a more efficient technique in this regard. Key words:Laser, power bleaching, tooth color introduction.

Evaluation of therapeutic laser influences on the healing of third-degree burns in rats according to different wavelengths.

INTRODUCTION: One of the most important innovative methods for tissue repair promotion is therapeutic lasers with photobiomodulution effects. The aim of this study was to investigate the effect of four different wavelengths of therapeutic laser (405, 532, 660 and 810 nm) on healing of third-degree burns from both clinical and pathological standpoints in rats. MATERIALS AND METHODS: 60 male Wistar rats were used. Animals were anesthetized and dorsal hairs were shaved and third-degree skin burns were created by use of a 95°C copper stamp. Lesions were irradiated with 1.5 J/cm2 energy densities and 200 mW/cm2 power densities. RESULTS: Statistical analyses of the "wound contraction" changes between five groups during the study showed more reduction in wound size in all laser groups in comparison with the control group; but these differences were not statistically significant except between red and blue lasers on the last day of experiment. DISCUSSION: Results of our study showed that using therapeutic lasers with green, blue, red, and infrared wavelengths may accelerate healing process. This trend is more obvious in red and infrared groups especially after acute phase, however, this effect was neither statistically nor clinically significant.

Effects of the bleaching procedures on enamel micro-hardness: Plasma Arc and diode laser comparison.

BACKGROUND AND AIMS: One of the major side effects of vital bleaching is the reduction of enamel micro-hardness. The purpose of this study was to evaluate the influence of two different bleaching systems, Plasma Arc and GaAlAs laser, on the enamel micro-hardness. MATERIALS AND METHODS: 15 freshly extracted human third molars were sectioned to prepare 30 enamel blocks (5×5 mm). These samples were then randomly divided into 2 groups of 15 each (n=15): a plasma arc bleaching group (: 350-700 nm) + 35% Hydrogen Peroxide whitening gel and a laser bleaching group (GaAlAs laser, λ: 810 nm, P: 10 W, CW, Special Tip) + 35% Hydrogen Peroxide whitening gel. Samples were subjected to the Vickers micro-hardness test (VHN) at a load of 50 g for 15s before and after treatment. Data were statistically analyzed by a Mann-Whitney test (p≤0.05). RESULTS: In the GaAlAs laser group, the enamel micro-hardness was 618.2 before and was reduced to 544.6 after bleaching procedures. In the plasma arc group, the enamel micro-hardness was 644.8 before and 498.9 after bleaching. Although both techniques significantly reduced VHN, plasma arc bleaching resulted in a 22.62% reduction in VHN for enamel micro-hardness, whereas an 11.89% reduction in VHN was observed for laser bleaching; this difference is statistically significant (p<0.001). CONCLUSION: Both bleaching techniques reduced enamel micro-hardness, although the reduction is much less significant with the GaAlAs laser than with the plasma arc. Therefore GaAlAs laser bleaching has fewer harmful effects than plasma arc in respect to enamel micro-hardness reduction.

A comparison of Er, Cr: YSGG laser with ultrasonic preparation on the seal of retrograde cavities.

BACKGROUND AND AIM: The aim of this in vitro study was to compare Er, Cr: YSGG laser with ultrasonic preparation on the seal of retrograde cavities. MATERIALS AND METHODS: Twenty-eight maxillary anterior teeth were used in this study. After removing the crowns, the canals were prepared with the step-back technique and filled with guttapercha. Three millimeters below the apex; each root was cut with a fissure diamond bur. The root surfaces were then covered with nail polish and three millimeters deep retrograde class I cavities were prepared, using Er, Cr: YSGG laser (group L=12 roots) or ultrasonic retro-tip (group U=12 roots). Four roots were arranged for negative and positive control groups. Retrograde cavities were then filled with mineral trioxide aggregate (MTA) and teeth were placed in 2% methylene blue dye for 72 hours. The amount of dye penetration in sagittal sections of each tooth was measured with a stereomicroscope. An independent sample t-test was used for statistical analysis. RESULTS: Cavities prepared with the Er, Cr: YSGG laser (1.61 + 0.81) showed significantly less micro-leakage than those prepared with the ultrasound (2.55+ 1.84) (P value =0.02). CONCLUSIONS: Under the conditions of this research, the use of Er, Cr: YSGG laser for retrograde cavity preparation causes significantly less apical leakage and may increase the success rate of endodontic surgeries.

The effect of red, green and blue lasers on healing of oral wounds in diabetic rats.

BACKGROUND AND OBJECTIVE: Many studies have demonstrated that low-level laser therapy (LLLT) can improve wound healing in non-diabetic and diabetic animals. We compared the effects of red, green, and blue lasers in terms of accelerating oral wound healing in diabetic rats. MATERIAL AND METHODS: Diabetes was successfully induced in 32 male Wistar rats using intraperitoneal injection of Streptozotocin (150 mg/kg). After intraperitoneal injection of the anesthetic agent, a full-thickness oral wound (10 mm × 2 mm) was created aseptically with a scalpel on hard palate of the diabetic rats. The study was performed using red (630 nm), green (532 nm), and blue (425 nm) lasers and a control group. We used an energy density of 2J/cm2 and a treatment schedule of 3 times/week for 10 days. The area of wounds was measured and recorded on a chart for all rats. On the 10th day, the samples were then sacrificed and a full-thickness sample of wound area was prepared for pathological study. RESULTS: We observed a significant difference (p<0.001) in the mean slope values of wound healing between treatment and control groups. Moreover, the mean slope of wound healing differed significantly between red laser and two other lasers - blue and green (p<0.001). The mean slopes of wound healing were not significantly different between blue laser and green laser (p=0.777). CONCLUSION: The results of the present study provide evidence that wound healing is slower in control rats compared to the treatment groups. Moreover, the findings suggest that wound healing occurs faster with red laser compared to blue and green lasers.

Pyogenic Granuloma: Surgical Treatment with Er:YAG Laser.

INTRODUCTION: Pyogenic granuloma (PG) is a common tumor-like growth of the oral cavity, considered to be of non-neoplastic nature, often caused by constant low-grade trauma as well as poor oral hygiene and maybe due to hormonal disturbances. Surgical excision, and removal of underlying cause in some cases, is the preferred method of treatment as it is only a benign lesion.In order to remove this lesion, scalpel, cryosurgery and laser are used. Currently different lasers, with adequate parameters, are used for the surgery of PG, which include CO2 (Carbon Dioxide Laser), Nd:YAG (Neodymium-Doped Yttrium Aluminium Garnet), Diode and Er Family amongst others. In this present case, due to the proximity of the lesion with dental hard tissue, Er:YAG (Erbium-Doped Yttrium Aluminum Garnet) laser appears to be the more appropriate laser. The application of Laser is also a newly recommended technique. The aim of this study is to assess the stages of treatment, recovery and recurrence of PG when the Er:YAG laser is used. Furthermore this study aims to also evaluate the friendliness of this method with regards to the surgeon (therapist). CASE REPORT: A 24-year-old female was referred to the Laser Research Center of Dentistry of Tehran University of Medical Sciences with a complaint of gingival overgrowth and bleeding. This lesion was in the buccal and palatal side of the 5 and 6 maxillary teeth. Treatment plan included an excisional biopsy of the lesion using Er:YAG laser (3W, 300mJ, 10Hz, Short pulse, with contact headpiece). The bones were then cleaned of soft tissue before being smoothed using a curette. The excised specimen was preserved and sent for histopathological examination. RESULTS: The patient reported no pain after surgery and did not use any systemic antibiotics. The patient was satisfied after the surgery. Chlorhexidine mouthwash was given to the patient. Pathology results confirmed Pyogenic granuloma.After 2 weeks, complete healing was observed. The 9-month follow-up was also carried out in order to check the process of healing as well as the recurrence. CONCLUSION: Excisional surgery is the preferred treatment method for PG. The application of laser can be considered as an effective and safe technique for excision of this lesion with minimal invasion and many clinical advantages such as less intra-operative bleeding, hemostasis and reduced pain and times of healing.