Systemic Effects of Photobiomodulation on the Morphology of the Thyroid and Sublingual Glands: A Study in Rabbits.

To investigate whether photobiomodulation (PBM) applied in a clinical situation with the purpose of improving the healing process of implants placed in the rabbit mandible would cause any morphological change in the thyroid and sublingual glands as a systemic effect of laser irradiation. Thirty-two New Zealand rabbits were randomly divided into four groups of eight animals each, one control group (CI, nonirradiated animals) and three experimental groups (EI, EII, and EIII) that received PBM postoperatively with an aluminum/gallium/arsenide laser diode (Theralase) at a wavelength of 830 nm (infrared) and 50 mW output power applied to two irradiation fields per session, for a total of seven sessions. All rabbits underwent surgical extraction of the mandibular left incisor, followed by immediate placement of an osseointegrated implant in the fresh socket.

Peri-implant osseointegration after low-level laser therapy: micro-computed tomography and resonance frequency analysis in an animal model.

The purpose of the present study is to evaluate the effects of low-level laser therapy on the osseointegration process by comparing resonance frequency analysis measurements performed at implant placement and after 30 days and micro-computed tomography images in irradiated vs nonirradiated rabbits. Fourteen male New Zealand rabbits were randomly divided into two groups of seven animals each, one control group (nonirradiated animals) and one experimental group that received low-level laser therapy (Thera Lase®, aluminum-gallium-arsenide laser diode, 10 J per spot, two spots per session, seven sessions, 830 nm, 50 mW, CW, Ø 0.0028 cm).

Histomorphometric assessment of the influence of low-level laser therapy on peri-implant tissue healing in the rabbit mandible.

Objective: The purpose of this study was to demonstrate the effect of low-level laser therapy (LLLT) on the peri-implant bone healing process in the rabbit mandible.

Background Data: LLLT has been shown to accelerate tissue repair and osseointegration of implants placed into the rabbit tibia. However, the beneficial effects of LLLT have never been tested in the rabbit mandible, which would more closely mimic the human situation.

Effect of three different protocols of low-level laser therapy on thyroid hormone production after dental implant placement in an experimental rabbit model.

Objective: The purpose of this study was to assess the systemic effects of low-level laser therapy (LLLT) on thyroid gland function and, consequently, calcium regulation - as measured by serum triiodothyronine (T3), thyroxine (T4), and free calcium levels - when administered after dental implant placement in a rabbit model.

Background Data: Protocols for the use of laser therapy in several clinical procedures are currently under investigation, as not all of the actions and systemic effects of laser irradiation have been clearly established.

Materials And Methods: Forty male adult New Zealand rabbits were distributed across five groups of eight animals each: two control groups (C-I and C-II) of unirradiated animals, and three experimental groups (E-5, E-10, and E-20), each exposed to a distinct dose of gallium-aluminum-arsenide (GaAlAs) laser [λ=830 nm, 50 mW, continuous wave (CW)] every 48 h for a total of seven sessions.

Finite element analysis of masticatory stress on neoformed bone tissue after distraction osteogenesis and low-level laser therapy: a pilot study.

Objective: This study aimed to understand the action of masticatory forces on an implant virtually introduced into the sheep mandible after distraction osteogenesis and low-level laser therapy (LLLT) by using finite element analysis.

Background Data: Distraction osteogenesis as an alternative for bone reconstruction that may be used in the treatment of deformities.

Methods: Four ewes underwent distraction osteogenis to elongate the left mandibular body by 15 m, and three of them underwent LLLT with the purpose of improving bone properties.

Systemic effects of LLLT on bone repair around PLLA-PGA screws in the rabbit tibia.

To evaluate the systemic effects of low level laser therapy (LLLT) on the early stages of bone repair after implantation of poly-L-lactic/polyglycolic acid (PLLA-PGA) screws 24 rabbits were randomly allocated to one of two groups, experiment or control. Each animal underwent implantation of one 5 × 1.5 mm PLLA-PGA screw in each tibia (right and left).

Effect of low-level laser therapy on incorporation of block allografts.

Objective: To assess the effect of low-level laser therapy (LLLT) on the incorporation of deep-frozen block allografts in a rabbit model.

Background Data: Studies have shown that LLLT has beneficial effects on tissue repair and new bone formation.

Methods: Bone tissue was harvested from two rabbits, processed by deep-freezing and grafted into the calvaria of 12 animals, which were then randomly allocated into two groups: experimental (L) and control (C).

Assessment of marginal adaptation after apicoectomy and apical sealing with Nd:YAG laser.

Objective: Recurrent periapical disease poses a substantial challenge to the dental practitioner. However, the use of novel methods and materials in periapical surgery has increased the success rates of treatment. The objective of this study was to assess the effects of mineral trioxide aggregate (MTA) retrofilling and apical sealing with Nd:YAG laser (at 10 Hz, 150 mJ, 1.

Assessment for treatment of tripod fractures of the zygoma with microcompressive screws.

Purpose: The present prospective study sought to evaluate a new rigid internal fixation device called a "neck screw," which was applied to patients presenting with a tripod fracture of the zygomaticomaxillary complex.

Patients And Methods: Seventeen patients with tripod fractures received surgical treatment from 2007 to 2010, and had their zygomaticomaxillary complex monofragments fixed using the neck screw protocol. The adequacy of fracture reduction, stability of the zygomatic monofragment after fixation, cosmetic outcomes, and postoperative complications were used to determine the efficacy of this protocol.

Retinoblastoma and p53 protein expression in pre-malignant oral lesions and oral squamous cell carcinoma.

The retinoblastoma (Rb) and p53 genes play a fundamental role in cell cycle mechanisms, and their deregulation is related to many steps of oral cancer carcinogenesis. This study was conducted to evaluate the expression of the p53 and Rb proteins in malignant and pre-malignant oral cavity lesions. This retrospective study was conducted at the Federal University of Bahia, Salvador, Brazil, and the Molecular Biology Laboratory of the Otorhinolaryngology Department at the University of Heidelberg, Heidelberg, Germany.

A preliminary study of hardness and modulus of elasticity in sheep mandibles submitted to distraction osteogenesis and low-level laser therapy.

Objectives: To investigate the quality of newly formed bone in sheep mandibles submitted to distraction osteogenesis and low-level laser therapy (LLLT), based on hardness and modulus of elasticity values. The ideal moment for laser application (during the latency/activation period vs. during the bone consolidation period) was also evaluated.

Histological and physical analysis of bone neoformation by osteogenesis distraction: A preliminary report.

Introduction: Osteogenesis distraction (OD) is a mainstream technique in maxillofacial surgical reconstruction with varied applications. OD technique employs a distractor with the aim to get new bone in the site of interest. Osseous maturation time is necessary before the device can be removed and few patients' complaint of related discomfort, especially when these devices are external, and induces superficial infections, paresthesia, hypertrophic scars and social relationship difficulties.

Analysis of the morphology and composition of tooth apices apicectomized using three different ablation techniques.

Objectives: To investigate apicectomies performed using burs, a CO2 laser or an Er:YAG laser and to evaluate the following aspects: morphology of apicectomized surfaces, presence of failures at the dentin/obturation material interface (marginal fit) of the apical portions of the root canals, and the proportions of chemical elements in the apicectomized surfaces.

Study Design: Twenty-four teeth were divided into three groups of eight and each group underwent apicectomy by one of three different ablation techniques: bur, CO2 laser or Er:YAG laser. The morphology of the apicectomized surfaces was then analyzed using scanning electron microscopy and their chemical composition was analyzed by energy dispersive spectroscopy.

Transference of virtual planning and planning over biomedical prototypes for dental implant placement using guided surgery.

Objectives: This study evaluated the transference of virtual planning and planning over biomedical prototypes for dental implant placement using guided surgery.

Material And Methods: This experiment was conducted with 11 identical replicas of a human edentulous mandible. For each mandible, models and surgical guides were manufactured using stereolithography.

Histological evaluation of the effect of low-level laser on distraction osteogenesis in rabbit mandibles.

Objectives: This study evaluated the action of low level laser therapy (LLLT) on the percentage of newly formed bone in rabbit mandibles that underwent distraction osteogenesis (DO).

Study Design: Ten rabbits underwent bone lengthening according to the following protocol: Latency - 3 days; Activation - 7 days 0.7 mm/d; and Consolidation - 10 days.

CO(2), Er: YAG and Nd:YAG lasers in endodontic surgery.

Objectives: CO(2), Er:YAG and Nd:YAG lasers have been used in endodontic surgery. This in vitro study evaluated 1% Rhodamine B dye penetration using computer-assisted morphometry (ImageTool Software) of 108 endodontically treated human permanent canines.

Material And Methods: Teeth were divided into 9 groups according to the technique used: A: 90-degree apicoectomy with bur, root-end cavity preparation with ultrasound and filled with MTA; B: 90-degree apicoectomy with bur, root-end cavity prepared with ultrasound and filled with MTA, and treatment of apical surface with CO(2) laser (1 W, CW/CW); C: 90-degree apicoectomy with bur, and treatment of apical surface with Nd:YAG laser (150 mJ, 10 Hz); D: 90-degree apicoectomy with bur, and treatment of apical surface with CO(2) laser,(1 W, CW/CW); E: apicoectomy with Er:YAG laser (400 mJ, 10 Hz), root-end cavity prepared with ultrasound and filled with MTA; F: apicoectomy with Er:YAG laser (400 mJ, 10 Hz) and treatment of apical surface with Nd:YAG laser (150 mJ, 10Hz); G: apicoectomy with CO(2) laser (5W, CW/SP), root-end cavity prepared with ultrasound and filled with MTA; H: irradiation of apical end with CO(2) laser (1 W, CW/CW); I: irradiation of apical end with Nd:YAG laser (150 mJ, 10 Hz).

Low-level laser therapy for implants without initial stability.

Objective: This study evaluated the effect of low-level infrared laser on removal torque values of implants with poor initial stability inserted in rabbit tibias.

Background Data: It is important to analyze the effects of laser radiation on bone repair when low-quality bone and implants with poor initial stability are used.

Materials And Methods: Thirty male white New Zealand rabbits (Oryctolagus Cuniculus) about 2 mo old and weighing 1.

Analysis of the systemic effect of red and infrared laser therapy on wound repair.

Objective: To evaluate, using histological analysis, the systemic action and repair process of wounds produced on the back of rats and treated with red, infrared, or both lasers applied directly or indirectly to the wounds.

Background Data: Skin tissue repair and wound healing are complex processes that involve a series of dynamic events. Many benefits are associated with biomodulation using laser therapy.

Effects of diode laser therapy on the acellular dermal matrix.

Acellular dermal matrix (ADM) was subcutaneously implanted into calvarian skin of male Wistar rats (n = 40). Low-level laser (lambda 685 nm, 4 J/cm(2)) was locally applied in experimental group (n = 20) above the skin flap. Grafts were harvested at 1, 3, 7 and 14 days after surgery and underwent histological analyses.

Effects of low-level laser therapy on bone formed after distraction osteogenesis.

This study evaluated the effect of low-level laser therapy (LLLT) on the chemical composition, crystallinity and crystalline structure of bone at the site of distraction osteogenesis. Five rabbits were subjected to distraction osteogenesis (latency = 3 days; rate and frequency = 0.7 mm/day for 7 days; consolidation = 10 days), and three were given LLLT with arsenide-gallium-aluminum (AsGaAl; 830 nm, 40 mW): 10 J/cm(2) dose per spot, applied directly to the distraction osteogenesis site during the consolidation stage at 48 h intervals.

Effect of titanium surface roughness on human bone marrow cell proliferation and differentiation: an experimental study.

Purpose: To assess the proliferation and differentiation of human bone marrow-derived cells cultured on titanium surfaces with different roughness characteristics.

Methods: Cells obtained from the iliac crest of an adult human donor were routinely processed and cultured on titanium surfaces of varying roughness, according to their preparation method: polishing only (smooth surface) and polishing followed by etching with HF/HNO3 for 15 and 30 minutes (rough surfaces). Surfaces were assessed using scanning electronic microscopy and profilometry.

Is 3D-CT reformation using free software applicable to diagnosis of bone changes in mandibular condyles?

Objectives: This study evaluated the agreement of computed tomography (CT) imaging using 3D reformations (3DR) with shaded surface display (SSD) and maximum intensity projection (MIP) in the diagnosis of bone changes in mandibular condyles of patients with rheumatoid arthritis (RA), and compared findings with multiplanar reformation (MPR) images, used as the criterion standard.

Material And Methods: Axial CT images of 44 temporomandibular joints (TMJs) of 22 patients with RA were used. Images were recorded in DICOM format and assessed using free software (ImageJ).

Parent and caretaker knowledge about avulsion of permanent teeth.

Traumatic dentoalveolar injuries are frequent in children and adolescents, affecting teeth, their supporting structures and adjacent soft tissues and contributing to the appearance of major psychosocial and economic problems. Tooth avulsion, the most severe dentoalveolar lesion, is a dental emergency. The prognosis of avulsed teeth significantly depends on prompt and efficient action at the site of the accident, thus requiring that parents or caretakers be knowledgeable about the correct management of this situation.

Marginal adaptation of root-end filling materials: an in vitro study with teeth and replicas.

Aim: The purpose of this investigation was to evaluate the marginal adaptation of five root-end filling materials.

Methods And Materials: Fifty human single-rooted teeth were resected 3 mm from the apex. Root-end cavities were then prepared using an ultrasonic tip and filled with one of the following materials: silver amalgam without zinc, white MTA-Angelus, white Portland cement (PC), Vitremer, and GC Fuji Ortho LC.

Dimensional error of selective laser sintering, three-dimensional printing and PolyJet models in the reproduction of mandibular anatomy.

Background: Selective laser sintering (SLS), three-dimensional printing (3DP) and PolyJet are rapid prototyping (RP) techniques to fabricate prototypes from virtual biomedical images. To be used in maxillofacial surgery, these models must accurately reproduce the craniofacial skeleton.

Purpose: To analyze the capacity of SLS, 3DP and PolyJet models to reproduce mandibular anatomy and their dimensional error.