Background and aims: It is said that the average frequency of bone fracture in hospitalized children with severe cerebral palsy (unable to remain seated) is 1% (0.2 to 2.0%). Cerebral palsy patients' bones are known to be vulnerable to fracture, and refractory bone atrophy may be observed. However, the effect of low level laser therapy (LLLT) on bone density or bone metabolism has not been fully investigated. In recent years, tests for bone density or bone metabolism markers have become available.
Material and Methods: In this study, we evaluated changes in bone density and bone metabolism markers in 4 children with severe cerebral palsy who underwent LLLT for an average of 22 days.
Results: B-ALP, a marker of ossification, increased 1 month after the start of irradiation in 3 of the 4 subjects and returned to a level close to the pre-irradiation level 2 months after the start of irradiation. In the remaining subjects in whom B-ALP failed to increase, B-ALP had been low before irradiation. Urinary N-terminal telopeptide (NTx) levels, a marker of bone resorption, decreased in 3 of the 4 subjects after the start of irradiation and remained low even 10 months later. Serum NTx levels tended to decrease in 3 of the 4 subjects. The levels of serum NTx/Crea, Deoxy-Pyridinoline (DPd) and DPd/Crea (DPd/Crea) also decreased in 3 of the 4 subjects. Transient decreases in intact parathyroid hormone (PTH) levels were observed in all 4 cases. Changes were particularly apparent in 2 cases: one with high NTx levels, which showed enhanced bone resorption, and one with high PTH levels, probably due to a vitamin D (VitD) deficiency. Although the metacarpal bone density measured by DIP was found to be lower than in normal children, there were no changes due to LLLT.
Conclusions: These results suggest that LLLT has a positive influence on bone metabolism in that it temporarily increases bone formation and suppresses bone resorption while also tending to improve secondary hyperparathyroidism caused by VitD deficiency. Enhanced bone resorption in the case with high NTx levels was noteworthy, together with marked changes in the case with high PTH levels due to VitD deficiency. These positive influences on bone metabolism merit attention as potential new indications of LLLT.

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Introduction: Maintaining deciduous teeth as long as possible represents a goal in pediatric dentistry and avoids a plethora of health problems. Er:YAG carious decay treatment may help for prevention as well as during the curative processes.
Materials and Methods: An Er:YAG laser was used to ablate 30 carious lesions on primary teeth. Diagnosis being conventionally dressed, treatment was conducted in respect of the following parameters: Er:YAG laser (Lite Touch, Syneron): output power from 300 mJ (enamel) to 200 mJ (dentine), frequency 20 Hz, sapphire tip (diameter 1.3 mm), air water spray ratio 8 (39 ml/min), pulse duration 50 μsec., theoretical fluence ranging from 15.08 J/cm ² for dentin to 22.61 J/cm ² for enamel. Then cavity depth was controlled (observation + probe). Glass-ionomer cement (GC Fuji Triage capsule) or flowable composite resin or compomer were used to fill the cavities. Children's acceptance to Er-YAG laser treatment was evaluated. According to predefined criteria, each case was followed up for one month after treatment and then with further monthly follow-ups for one year.
Results: Clinical cases illustrate the validity of this clinical approach. The benefit of laser dental treatment has been shown to be the greatest in children. However, the lack of studies evaluating laser ablation capability in primary teeth restrains the adoption of this technology. The interaction between the Er:YAG laser and primary enamel and dentin depends on the composition of the tissues - a higher presence of water and lower presence of minerals- comparative to the permanent enamel and dentin. Thus, photoablation of primary enamel and dentin requires lower energy. This study shows that the laser parameters used (300 mJ/20 Hz for enamel and 200 mJ/20 Hz for dentin) are efficient enough for the ablation of tissues of deciduous teeth and moreover demonstrates to be well accepted by young patients.

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Background and aims: To determine if tooth structure or dental pulp of normal healthy human premolar teeth to be extracted for orthodontic reasons exhibit morphological or histological changes following dental anaesthesia by pulsed Nd:YAG laser and subsequent cavity preparation (CP).
Materials (Subjects) and Methods: 54 bilateral paired of human, healthy premolar teeth identified for inclusion in a clinical trial of Nd:YAG-induced anaesthesia and subsequently extracted for orthodontic reasons, were randomly divided into 4 treatment groups: Group 1 - teeth (n=44) were irradiated with 150 μs pulsed Nd:YAG laser-1064 nm (American Dental Laser, dLase300, Sunrise Technologies Inc., Folsom, CA, USA; Average power: 1.1 ± 0.2 W, power density: 3.9+ 0.7 W/cm ², area 0.28 cm ², 15 Hz; energy density:0. 260+ 0.047 J/cm ²) +Sham EMLA (cream without active component) followed by cavity preparation (CP); Group 2 - Teeth (n=44) - were treated with EMLA + Sham Laser (1 mW 632.8-nm He:Ne laser aiming beam only) with CP; Group 3 Teeth (n=10)- were irradiated with pulsed Nd:YAG laser as above but minus CP; Group 4 (n=10)- was a Control group with teeth untreated (no Laser, EMLA or CP). Clinical anaesthesia was assessed by electric pulp testing (EPT) and CP. Teeth in each of the 4 groups were processed for examination by i) scanning electron microscopy (SEM); ii) longitudinal undecalcified ground sectioning (LUGS); iii) light microscopy of pulpal tissues or iv) dye penetration.
Results: Both Laser and EMLA groups demonstrated no alteration to mineralized tooth structure and dentinal permeability. Mild superficial pulpal changes were found in both groups (3/18 teeth) and of no statistical difference (>0.99, the McNemar test). Neither Laser nor the Control groups minus CP, showed pulpal changes.
Conclusions: Low-power pulsed Nd:YAG laser dose, as used in the clinical trial to induce anaesthesia, does not cause morphological damage to the mineralized tooth structure. Both Laser and EMLA groups showed minor superficial pulpal change following cavity preparation which was not statistically significant. Laser and Control groups minus preparation had no pulpal changes.

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Objectives: Recently, photodynamic therapy (PDT) has been introduced as a new modality in oral bacterial decontamination. Besides, the ability of laser irradiation in the presence of photosensitizing agent to lethal effect on oral bacteria is well documented. Current research aims to evaluate the effect of photodynamic killing of visible blue light in the presence of plaque disclosing agent erythrosine as photosensitizer on Porphyromonas gingival is associated with periodontal bone loss and Fusobacterium nucleatum associated with soft tissue inflammation, comparing with the near infrared diode laser.
Materials and methods: Standard suspension of P. gingivalis and F. nucleatum were exposed to Light Emitting Diode (LED) (440-480 nm) used to photopolymerize composite resine dental restoration in combination with erythrosine (22 μm) up to 5 minutes. Bacterial sample were also exposed to a near-infrared diode laser (wavelength, 830 nm), using identical irradiation parameters for comparison. Bacterial samples from each treatment groups (radiation-only group, erythrosineonly group and light or laser with erythrosine group) were subcultured onto the surface of agar plates. Survival of these bacteria was determined by counting the number of colony forming units (CFU) after incubation.
Results: Exposure to visible blue light and diode laser in conjugation with erythrosine significantly reduced both species examined viability, whereas erythrosine-treated samples exposed to visible light suggested a statically meaningful differences comparing to diode laser. In addition, bactericidal effect of visible light or diode laser alone on P. gingivalis as black-pigmented bacteria possess endogenous porphyrins was noticeably.
Conclusion: Our result suggested that visible blue light source in the presence of plaque disclosing agent erythrosine could can be consider as potential approach of PDT to kill the main gramnegative periodontal pathogens. From a clinical standpoint, this regimen could be established as an additional minimally invasive antibacterial treatment of plaque induced periodontal pathologies.

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Background and Aims: Chronic knee joint pain is one of the most frequent complaints which is seen in the outpatient clinic in our medical institute. In previous studies we have reported the benefits of low level laser therapy (LLLT) for chronic pain in the shoulder joints, elbow, hand, finger and the lower back. The present study is a report on the effects of LLLT for chronic knee joint pain.
Material and Methods:Over the past 5 years, 35 subjects visited the outpatient clinic with complaints of chronic knee joint pain caused by the knee osteoarthritis-induced degenerative meniscal tear. They received low level laser therapy. A 1000 mW semi-conductor laser device was used to deliver 20.1 J/cm² per point in continuous wave at 830nm, and four points were irradiated per session (1 treatment) twice a week for 4 weeks.
Results: A visual analogue scale (VAS) was used to determine the effects of LLLT for the chronic pain and after the end of the treatment regimen a significant improvement was observed (p <0.001). After treatment, no significant differences were observed in the knee joint range of motion. Discussions with the patients revealed that it was important for them to learn how to avoid postures that would cause them knee pain in everyday life in order to have continuous benefits from the treatment.
Conclusion: The present study demonstrated that 830 nm LLLT was an effective form of treatment for chronic knee pain caused by knee osteoarthritis. Patients were advised to undertake training involving gentle flexion and extension of the knee.

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Background and Aims: Pregnancy tumours (PTs) are a non-neoplastic, reactive, inflammatory conditional gingival enlargement which occurs in the oral cavity during pregnancy. The lesion most frequently occurs on the gingiva but may also develop on the lip, tongue, oral mucosa and palate. When a large PT develops, it can interfere with mastication, speech, maintenance of oral hygiene and can be aesthetically disfiguring. The treatment of PTs depends upon the size of the lesion; smaller lesions can regress after parturition however large lesions need to be surgically removed. Conventional surgical techniques have the disadvantage of more bleeding from the surgical site and delay in healing of the scar tissue. The diode laser is a relatively new alternative to conventional surgical technique in intra-oral areas with the added advantage of bloodless procedures and rapid healing.
Case report: The purpose of the present study is to highlight the management of a PT in a 25-year-old female using a diode laser delivering a painless, bloodless procedure with rapid postoperative healing.
Conclusions: Diode laser excision of a persistent pregnancy tumour in a postpartum patient was safe and effective with minimal bleeding, good coagulation, and good wound healing. Among other lasers, the diode laser can therefore be considered for excisional treatment of persistent PTs.

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