Quality of life in young and middle age adult temporomandibular disorders patients and asymptomatic subjects: a systematic review and meta-analysis.

AIMS: To compare the difference in the quality of life between temporomandibular disorders (TMD) patients and non-TMD subjects diagnosed with the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) or the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD). METHODS: Medical Literature Analysis and Retrieval System Online (MEDLINE), Excerpta Medica database (EMBASE) and Latin American and Caribbean Health Sciences Literature (LILACS) databases were searched in studies published in English and Portuguese. The search was performed by two independent reviewers in duplicate. A manual search and the gray literature were also included. The inclusion criteria were clinical studies that used the RDC/TMD axis I and quality of life with standard questionnaires in young and middle-aged adult population (18-55 years). The data were analyzed quantitatively by combining the results in a meta-analysis using forest plots. The measure of effect used was the standardized mean difference (SMD) in depression levels. The Newcastle-Ottawa Scale (NOS) was used to evaluate the quality of the studies. The publication bias was assessed by funnel plots. The initial search included 806 articles without duplications. RESULTS: Twenty-four articles were included in the final systematic review. Of these, 9 were included in the meta-analysis, where it was shown a statistically significant in all axis I groups: (a) global TMD-groups I, II and III combined, N = 3829, SMD (95% CI) = 1.06 (0.65-1.51), p = 0.000; (b) group I-muscle disorders, N = 3,056, SMD (95% CI) = 0.82 (0.45-1.18), p = 0.000; (c) group II-disc displacements, N = 3,184, SMD (95% CI) = 0.59 (0.26-0.91), p = 0.000; and (d) group III-arthralgia/arthritis/arthrosis, N = 2781, SMD (95% CI) = 0.98 (0.59-1.36), p = 0.000. When compared to controls. CONCLUSIONS: Quality of life is affected in all axis I TMD patients, especially in groups I and III with higher pain intensity and disability as compared to group II.

Efficacy of laser therapy in the management of bisphosphonate-related osteonecrosis of the jaw (BRONJ): a systematic review.

Bisphosphonate-related osteonecrosis of the jaw is a well-known potential side effect of long-term bisphosphonate therapy; the primary objective of the treatment should be to improve patient quality of life through pain and infection management, to prevent the development of new lesions, and to slow disease progression. In recent years, the use of laser for bisphosphonate-related osteonecrosis of the jaw has become more widespread, due to its use of administration and widely reported beneficial effects on tissue healing. The present systematic review of the literature sought to elucidate whether low-level laser therapy has positive effects on the treatment of bisphosphonate-related osteonecrosis of the jaw. We conducted a systematic search of the PubMed, EMBASE, and Cochrane Library electronic databases, with no restrictions on language or year of publication. Search strategies were formulated using keywords and Boolean operators. The electronic search strategy retrieved 55 records. From 55 articles, 16 were selected for full-text review, and of these, 10 were ultimately included for data analysis in this review. Our findings show that treatment modalities including laser were associated with superior outcomes in terms of cure or improvement of bisphosphonate-related osteonecrosis of the jaw lesions as compared with conventional surgical and/or conservative drug therapy. It can be concluded that combined treatment with antibiotics, minimally invasive surgery (including Er:YAG laser surgery), and low-level laser therapy in the early stages of the disease should be the gold standard for bisphosphonate-related osteonecrosis of the jaw management.

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). The experiment group received infrared laser irradiation (830 nm, 4 J, 100 mW, 10.1 s) over the right paw immediately after implantation and every 48 h thereafter, for a maximum of seven sessions. The control group was not irradiated. Both groups were divided into three subgroups according to the observation period (5, 15, or 30 days), after which animals were euthanized. The results observed in the left paw of experimental animals were compared with the left paws of control animals. We also compared the right and left paws of experimental animals so as to compare local and potential systemic effects. Bone specimens were analyzed to assess the extent of peri-implant bone formation, quantitative analysis revealed greater bone formation in the left tibia of experimental animals as compared to controls on 5-day follow-up. Descriptive analysis revealed slightly larger and thicker trabeculae in the irradiated animals at 5 days post-procedure. There were no significant differences at any other point in time. As used in this study, LLLT had a positive systemic effect on the early stages of bone formation.

Depression and the risk of developing temporomandibular disorders in different diagnostic groups: A systematic review with meta-analysis.

OBJECTIVE: To evaluate the role of depression in the development of TMD groups. METHODS: This systematic review with meta-analysis compared the prevalence and scores of depression between TMD groups and controls. RESULTS: The results showed that depression was a significant risk factor in the development of RDC/TMD axis I muscle disorders (group I) and arthralgia/osteoarthritis/osteoarthrosis (group III), and non-significant for disc displacements (group II). Severe depression had almost four times the risk of developing TMD as compared to moderate depression. CONCLUSION: These findings suggest that addressing psychological factors in general, and depression in particular, in the managemenof TMD is crucial, especially in those TMD groups with higher pain levels (I and III), and the TMD pain reduction is crucial in reducing depression levels.

Assessment of Resorbable and Non-resorbable Fixation Systems in Sagittal Split Ramus Osteotomy: An In vitro Study.

Objective: The internal fixation has been purpose of study for many years, but there is still no consensus on the best method of fixation in relation to resistance for bilateral sagittal split ramus osteotomy (BSSO) using plates. Therefore, the aim of this study was to assess five different methods of osteosynthesis using resorbable and non-resorbable plates and screws in simulated sagittal split osteotomy (SSO) of the mandibular ramus. Materials and Methods: SSO was performed in 25 polyurethane synthetic mandibular replicas. The distal segments were moved forward 5 mm, and the specimens were grouped according to the fixation method: Inion resorbable plate, KLS resorbable plate, standard four-hole titanium miniplate (Medartis), two standard four-hole titanium miniplates (Medartis) and an adjustable titanium miniplate (Slider/Medartis). Mechanical evaluation was performed by applying compression loads to first molar using an Instron universal testing machine up to a 5 mm displacement of the segments. Resistance forces were obtained in Newtons (N), and statistical analysis was performed using the software R v. 3.5 with significance level of 0.05. Linear mixed models were used to compare the force required to move each type of plate. Results: The results showed that the resistance of SSO was better accomplished using two titanium miniplates and KLS resorbable plate showed the least resistance. However, both titanium and resorbable plates behaved similarly in small displacements, which are most commonly observed in BSSO postoperative time. Conclusion: It can be concluded that both resorbable and non-resorbable systems might offer suitable mechanical resistance in the procedures where there are no mechanical postoperative complications.

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

Objective: 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. Methods: 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. The experimental groups EI, EII, and EIII received PBM at an energy density of 5, 2.5, and 10 J/cm2, respectively, per irradiation field. Results: There was no histomorphometric change in any of the groups. Conclusions: PBM, based on the irradiation protocol used in this study, does not cause morphological changes in the thyroid and sublingual glands when used to stimulate peri-implant bone healing in the rabbit mandible.

Neural Regenerative Potential of Stem Cells Derived from the Tooth Apical Papilla.

The regenerative effects of stem cells derived from dental tissues have been previously investigated. This study assessed the potential of human tooth stem cells from apical papilla (SCAP) on nerve regeneration. The SCAP collected from nine individuals were characterized and polarized by exposure to interferon-γ (IFN-γ). IFN-γ increased kynurenine and interleukin-6 (IL-6) production by SCAP, without affecting the cell viability. IFN-γ-primed SCAP exhibited a decrease of brain-derived neurotrophic factor (BDNF) mRNA levels, followed by an upregulation of glial cell-derived neurotrophic factor mRNA. Ex vivo, the co-culture of SCAP with neurons isolated from the rat dorsal root ganglion induced neurite outgrowth, accompanied by increased BDNF secretion, irrespective of IFN-γ priming. In vivo, the local application of SCAP reduced the mechanical and thermal hypersensitivity in Wistar rats that had been submitted to sciatic chronic constriction injury. The SCAP also reduced the pain scores, according to the evaluation of the Grimace scale, partially restoring the myelin damage and BDNF immunopositivity secondary to nerve lesion. Altogether, our results provide novel evidence about the regenerative effects of human SCAP, indicating their potential to handle nerve injury-related complications.

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. The objective of the present study was to assess the level of knowledge of parents or caretakers concerning the management of tooth avulsion and to investigate the association between level of knowledge and schooling, monthly family income and age. We interviewed 107 parents or caretakers using a 12-item questionnaire comprising objective questions whose answers received a score from 0 to 3. The results show that 99% of those interviewed would immediately seek professional help; however, 71% did not know what avulsion was. Only 3% would use milk as storage medium and 16% would attempt replantation of the avulsed tooth. The distribution of final means for the overall level of parent or caretaker knowledge was 44.63% for score 3, 15.88% for score 2, 17.99% for score 1 and 21.47% for score 0, showing a low level of knowledge concerning tooth avulsion. Schooling, monthly family income and age were not associated with the knowledge scores for any of the 12 questions. The level of parent and caretaker knowledge concerning the management of tooth avulsion is low, without association with age, schooling and monthly family income.

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. The apical portion of the roots was then sectioned to obtain two 1 mm thick transversal sections. Epoxy resin replicas of these apical sections were fabricated for an analysis of marginal adaptation. Scanning electron microscopy (SEM) was used to determine gaps in the adaptation of the root-end filling materials at the interface between them and the dentin. The Kruskal-Wallis test and a multiple comparison test were used for statistical data analysis. The Spearman correlation coefficient was used to determine the correlation between the results found for teeth and replicas. RESULTS: Materials containing calcium oxide (MTA and PC) showed similar results. Resin modified glass ionomer cements (GICs) presented similar variations in marginal adaptation, but Vitremer showed significantly greater marginal adaptation when compared to GC Fuji Ortho LC. CONCLUSION: A positive and significant correlation was observed between marginal adaptation values found in the teeth and their replicas. CLINICAL SIGNIFICANCE: The use of ionomers as root-end filling materials may improve clinical outcomes in periradicular surgery.

Analgesic action of laser therapy (LLLT) in an animal model.

OBJECTIVES: To evaluate the analgesic effect of laser therapy on healthy tissue of mice. STUDY DESIGN: Forty-five animals were divided in three groups of 15: A--infrared laser irradiation (830 nm, Kondortech, São Carlos, SP, Brazil); B--red laser irradiation (660 nm, Kondortech, São Carlos, SP, Brazil); C-- ham irradiation with laser unit off. After laser application, the mice remained immobilized for the injection of 30 microl of 2% formalin in the plantar pad of the irradiated hind paw. The time that the mouse kept the hind paw lifted was measured at 5 min intervals for 30 minutes. RESULTS: Results showed statistically significant differences comparing the control group with the infrared laser group at 5, 20, 25 and 30 accumulated minutes, and with the red laser group at all time points. The analysis of partial times, at each 5 minutes, showed statistically significant differences between the control and the laser groups up to 20 minutes. CONCLUSIONS: Laser therapy had an analgesic effect and red laser had the best results.

Histologic study of the effect of laser therapy on bone repair.

AIM: This study used histologic analysis and HE staining to evaluate laser biomodulation of bone repair in cavities made in the femurs of rats that underwent non-ablative laser irradiation. METHODS AND MATERIALS: Eighteen male Wistar rats weighing 300 to 400 grams were randomly assigned to three groups of six animals each. A surgical defect site was produced with a trephine about 2 mm in diameter under abundant irrigation. In Group I the complete surgical protocol to produce a bone defect was followed but without laser radiation (control). In Group II a continuous wave 830 nm infrared laser was used at 10 J/cm2 and 50 mW at each point of the surgical site. In Group III a continuous wave 685 nm infrared laser at 10J/cm2 and 35 mW was used at each point of surgical site. The animals were irradiated at intervals of 48 hours beginning immediately after the preparation of the defect and were sacrificed on the 15th, 21st, and 30th days. Slides were studied by means of descriptive analysis. RESULTS: Greater degrees of new bone formation and vertical regeneration were found in the irradiated groups than in the control group. CONCLUSION: Laser therapy in this study protocol was efficient in promoting bone repair. CLINICAL SIGNIFICANCE: The use of laser technology has been used to improve the clinical results of bone surgeries and to promote a more comfortable postoperative period and quicker healing.

Effect of low-level laser therapy on tissue repair after dental extraction in rats administered zoledronic acid and dexamethasone.

Bisphosphonates (BPs) are being increasingly used for the treatment of metabolic and oncological pathologies involving the skeletal system. Because of the severity of the BP associated osteonecrosis of the jaws, the difficulties of treatment, and patient discomfort, additional support methods for their management are needed. Laser therapy has an easy handling, photobiostimulator effect on tissues healing, so it can be considered a preferred therapy. The aim of this study was to evaluate the influence of low-level laser therapy in the 685- and 830-nm wavelength in the healing process of the bone and soft tissues in rats under BP therapy [zoledronic acid (ZA)] and dexamethasone concomitantly that underwent a surgery for the extraction of upper molars. There were statistically significant differences in the clinical evaluation of the wound and the weight of the animals. Regarding the histological evaluation, it was possible to observe the different maturations of the healing stage between groups. The effect of drug therapy with ZA and dexamethasone in the bone tissue repair process induces osteonecrosis of the jaw in rats and slows down the healing process. In the laser groups, at the stipulated dosimetry, a positive influence on the bone and soft tissue repair process was observed.

Depression, somatization, and sleep disorders as risk factors for temporomandibular disorders development: a population-based case-control study / Depressão, somatização e distúrbios do sono como fatores de risco para o desenvolvimento de disfunções temporomandibulares: um estudo de controle de casos baseado na população / Depresión, somatización y trastornos del sueño como factores de riesgo para el desarrollo de trastornos temporomandibulares: un estudio de casos y controles de base poblacional

The objective of this study was to determine the association between temporomandibular disorders (TMD) with depression, somatization and sleep disorders in the city of Maringá, Brazil. A total of 1,643 participants were selected from the Brazilian Unified Health System (SUS). Of these, the test group consisted of 84 participants who had moderate or severe limitations due to TMD pain and the control group consisted of 1,048 participants with no pain. There was a highly statistically significant difference (p<0.001) between cases and controls regarding depression (82.1 versus 37.4%), somatization (84.5 versus 31.4%), and sleep disorders (84.6 versus 36.4%), in moderate to severe levels. The levels of moderate to severe depression, somatization and sleep disorders were significantly higher in TMD subjects with high TMD pain disability. The risk of developing TMD increased 4 to 5 times when the individual has moderate to severe levels of depression, somatization, and sleep disorders.

O objetivo deste estudo foi determinar a associação entre disfunções temporomandibulares (DTM) com depressão, somatização e distúrbios do sono na cidade de Maringá, Brasil. Foram selecionados 1.643 participantes atendidos no Sistema Único de Saúde (SUS). Desses, o grupo caso foi formado por 84 participantes que apresentaram limitações moderada ou grave devido à dor na DTM e o grupo controle foi formado por 1.048 participantes com ausência de dor. Verificou-se diferença estatisticamente significativa (p<0,001) entre casos e controles em relação à depressão (82,1 versus 37,4%), somatização (84,5 versus 31,4%) e distúrbios do sono (84,6 versus 36,4%), em níveis moderados a graves. Os níveis de depressão moderada a grave, somatização e distúrbios do sono foram significativamente mais altos em indivíduos com DTM com alta incapacidade devido à dor por DTM. O risco de desenvolver DTM aumentou quatro a cinco vezes quando o indivíduo apresenta níveis moderados a graves de depressão, somatização e distúrbios do sono.

El objetivo de este estudio fue determinar la asociación entre los trastornos temporomandibulares (TMD) con la depresión, la somatización y los trastornos del sueño en la ciudad de Maringá, Brasil. Un total de 1.643 participantes fueron seleccionados del Sistema Único de Salud (SUS) de Brasil. (SUS). De estos, el grupo de casos fue formado por 84 participantes que presentaban limitaciones moderadas o graves debido al dolor TMD y el grupo de control estaba formado por 1.048 participantes sin dolor. Hubo una diferencia estadísticamente significativa (p <0,001) entre casos y controles con respecto a depresión (82,1 frente a 37,4%), somatización (84,5 frente a 31,4%) y trastornos del sueño (84,6 frente a 36,4%), en niveles moderados a severos. Los niveles de depresión moderada a grave, somatización y trastornos del sueño fueron significativamente más altos en personas con TMD con alta discapacidad por dolor en TMD. El riesgo de desarrollar TMD aumenta de 4 a 5 veces cuando el individuo tiene niveles moderados a severos de depresión, somatización y trastornos del sueño.

Histopathological, Microbiological, and Radiographic Analysis of Antimicrobial Photodynamic Therapy for the Treatment of Teeth with Apical Periodontitis: A Study in Rats' Molars.

OBJECTIVE: The aim of this study was to evaluate in vivo, by histological and radiographic analysis, the response of apical tissues of rats' teeth with experimentally induced apical periodontitis, after one- and two-session endodontic treatment with and without photodynamic therapy (PDT). A microbiological analysis was also performed to verify bacterial reduction after each treatment. BACKGROUND DATA: Studies carried out in recent years highlighted the antibacterial potential of PDT when associated with conventional endodontic therapy in vitro. Although the antimicrobial effect of PDT is well-established, tissue response to PDT in teeth with apical periodontitis lacks studies. METHODS: Thirty-two rats' root canals were assigned to four groups: one session/PDT-[chemomechanical preparation (CMP)+root canal filling (RCF)]; two sessions/PDT- [CMP+calcium hydroxide (CH) for 14 days+RCF]; one session/PDT+ [CMP+PDT+RCF], and two sessions/PDT+ [CMP+PDT+CH for 14 days+RCF]. For microbiological evaluation, samples were collected before and after proposed treatments. For radiographic and histological analysis, the animals were euthanized after 28 days and the mandibles surgically removed. RESULTS: PDT associated with conventional endodontic therapy was able to promote significant bacterial reduction in root canals with induced apical periodontitis, but this reduction was not significantly different to conventional endodontic therapy alone. Although radiographic evaluation showed no significant differences, histological analysis showed lower scores for neutrophils/eosinophils in PDT-treated groups and macrophages/giant cells in CH groups. CONCLUSIONS: The use of low-level laser as light source did not promote major improvement on radiographic and histological repair, but since the number of inflammatory cells slightly decreased, it may optimize repair by modulating inflammatory process. PDT may be indicated as an adjunct to conventional endodontic therapy for teeth with apical periodontitis, in association with an interappointment dressing with CH, in an attempt to produce better conditions to stimulate repair.

Relined fiberglass post: an ex vivo study of the resin cement thickness and dentin-resin interface.

The aim of this study was to evaluate the thickness of resin cements in the root thirds when using conventional fiberglass posts (CP) and relined fiberglass posts (RP) in weakened roots and to evaluate the morphological characteristics of the dentin-resin interface. Forty human maxillary anterior teeth had the crown sectioned below the cemento-enamel junction. The canals were endodontically treated and weakened with diamond burs. Teeth were divided into four groups (n = 10): Group 1 - CP + RelyX ARC; Group 2 - CP + RelyX U200; Group 3 - RP + RelyX ARC; and Group 4 - RP + RelyX U200. Prior to luting, 0.1% Fluorescein and 0.1% Rhodamine B dyes were added to an adhesive and resin cement, respectively. Slices were obtained from the apical, middle, and cervical thirds of the root. Confocal laser scanning microscopy images were recorded in four areas (buccal, lingual, mesial, distal) of each third. In each area, four equidistant measures of the resin cement were made and the mean value was calculated. The interface morphology was observed. The data were submitted to three-way ANOVA and Tukey's test (α = 0.05). The interaction between fiberglass posts, resin cement, and root thirds was significant (p < 0.0001). The resin cement thicknesses were significantly lower for RP in comparison with CP, except in the apical third. There was no significant difference between the resin cements for RP. There was formation of resin cement tags and adhesive tags along the root for RP. RP favored the formation of thin and uniform resin cement films and resin tags in weakened roots.

Photodynamic therapy in endodontics: a literature review.

Recently, several in vitro and in vivo studies demonstrated promising results about the use of photodynamic therapy during root canal system disinfection. However, there is no consensus on a standard protocol for its incorporation during root canal treatment. The purpose of this study was to summarize the results of research on photodynamic therapy in endodontics published in peer-reviewed journals. A review of pertinent literature was conducted using the PubMed database, and data obtained were categorized into sections in terms of relevant topics. Studies conducted in recent years highlighted the antimicrobial potential of photodynamic therapy in endodontics. However, most of these studies were not able to confirm a significant improvement in root canal disinfection for photodynamic therapy as a substitute for current disinfection methods. Its indication as an excellent adjunct to conventional endodontic therapy is well documented, however. Data suggest the need for protocol adjustments or new photosensitizer formulations to enhance photodynamic therapy predictability in endodontics.

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. The total dose per session was 5 J/cm(2) in E-5, 10 J/cm(2) in E-10, and 20 J/cm(2) in E-20. Animals in C-II and all experimental groups underwent surgical extraction of the mandibular left incisor followed by immediate placement of an osseointegrated implant (Nanotite(®), Biomet 3i(™)) into the socket. Animals in group C-I served as an absolute control for T3, T4, and calcium measurements. The level of significance was set at 5% (p≤0.05). RESULTS: ANOVA with Tukey's post-hoc test revealed significant differences in T3 and calcium levels among experimental groups, as well as significant within-group differences in T3, T4, and calcium levels over time. CONCLUSIONS: Although not reaching abnormal values, LLLT applied to the mandible influenced thyroid function in this model.

Influence of low-level laser therapy on the rate of orthodontic movement: a literature review.

OBJECTIVE: The purpose of this study was to review low-level laser therapy (LLLT) protocols that have been used to date, and to indicate which parameters appear to be most effective to guide future research. BACKGROUND DATA: Studies assessing the influence of LLLT on the rate of orthodontic tooth movement have produced controversial results as a result of methodological differences. METHODS: The MEDLINE(®) database (1975-2012) and the Cochrane library (subject 8) were reviewed. Clinical studies and animal experiments written in English and focusing on the effects of LLLT on the rate of orthodontic movement were browsed. Article selection was conducted by one reviewer and checked by a second investigator. RESULTS: A total of 109 articles were identified, of which 14 were selected for detailed analysis. Diode laser was used in all studies with different energies, frequencies, and doses. In animal studies, the most common and effective energy input was 54 J per session daily; in humans, it was 2 J per session on the first days of each month, with 72-96 h intervals. Orthodontic force also influenced orthodontic movement. A force of 10 g/force seems to be indicated for moving molars in rats, versus 150 g for canines in humans. CONCLUSIONS: Most authors report positive effects of the use of LLLT on speed increase of orthodontic tooth movement when compared with control or placebo groups. Diode laser, especially gallium aluminum arsenide, used continuously and in direct contact with the irradiated areas, was the most frequent protocol. Further studies are warranted to determine the best protocols with regard to energy, dose, and intervention schedule.

Radiopacities of glass ionomer cements measured with direct digital radiographic system.

PURPOSE: The purpose of this study was to determine and compare the radiopacities of 5 glass ionomer cements (GICs) of different thickness using a digital radiographic system-storage phosphor plate. METHODS: The GICs tested were Vitremer, Vitrofil LC, Magic Glass, Vitromolar, and Maxxion, distributed into the orifices of 16 acrylic plates made to a thickness of 2 mm, 3 mm, 5 mm, and 6 mm. Each plate was radiographed 3 times, and the images obtained were processed by computer. The images were read 3 times using the VixWin 2000 program, totaling 720 readings of radiographic density. One-way analysis of variance was applied for statistical analysis with identification of differ- ences using Scheffe's multiple comparisons test (α=5%). RESULTS: All the GICs varied in radiopacity according to thickness. Maxxion showedthe lowest value of radiopacity, whereas Magic Glass displayed the highest level of radiopacity at all thicknesses studied. However, Vitremer and Vitrofil LC showed similar results. CONCLUSION: It is important to know GIC radiopacities to help differentiate them from tooth structure and carious lesions as well as to use them correctly.

Relined fiberglass post: an ex vivo study of the resin cement thickness and dentin-resin interface

Abstract The aim of this study was to evaluate the thickness of resin cements in the root thirds when using conventional fiberglass posts (CP) and relined fiberglass posts (RP) in weakened roots and to evaluate the morphological characteristics of the dentin-resin interface. Forty human maxillary anterior teeth had the crown sectioned below the cemento-enamel junction. The canals were endodontically treated and weakened with diamond burs. Teeth were divided into four groups (n = 10): Group 1 - CP + RelyX ARC; Group 2 - CP + RelyX U200; Group 3 - RP + RelyX ARC; and Group 4 - RP + RelyX U200. Prior to luting, 0.1% Fluorescein and 0.1% Rhodamine B dyes were added to an adhesive and resin cement, respectively. Slices were obtained from the apical, middle, and cervical thirds of the root. Confocal laser scanning microscopy images were recorded in four areas (buccal, lingual, mesial, distal) of each third. In each area, four equidistant measures of the resin cement were made and the mean value was calculated. The interface morphology was observed. The data were submitted to three-way ANOVA and Tukey's test (α = 0.05). The interaction between fiberglass posts, resin cement, and root thirds was significant (p < 0.0001). The resin cement thicknesses were significantly lower for RP in comparison with CP, except in the apical third. There was no significant difference between the resin cements for RP. There was formation of resin cement tags and adhesive tags along the root for RP. RP favored the formation of thin and uniform resin cement films and resin tags in weakened roots.