Effects of low-level laser irradiation on osteoblast-like cells

La modulazione dei processi biologici legati al rimodellamento osseo tramite laser a bassa dose è una strategia promettente perché semplice, non invasiva e senza apparenti effetti indesiderati. L’ampio range di parametri laser proposti in letteratura rende tuttavia impossibile estrapolare linee guida univoche per la pratica clinica. L’obiettivo è stato quindi quello di determinare la dose ottimale di irradiazione laser sugli osteoblasti, cellule chiave nel processo di rimodellamento osseo. Sono stati valutati in vitro gli effetti di diverse dosi di laser su cellule umane simil-osteoblastiche Saos-2, analizzando vitalità cellulare, contenuto di DNA e rilascio di alcune proteine importanti per rimodellamento osseo e neoangiogenesi. Le dosi risultate più biostimolanti sono state poi utilizzate per indagare gli effetti del laser su migrazione e proliferazione di cellule Saos-2 sottoposte ad un protocollo di microferita in vitro, su espressione genica e rilascio di alcune proteine legate al metabolismo osseo, su vitalità cellulare e contenuto di DNA. La vitalità cellulare è stata modulata in maniera dose-dipendente dalla irradiazione singola con laser GaAlAs (915 nm) per 10, 48, 96, 193 e 482 secondi usando dosi di 1, 5, 10, 20 e 50 J∕cm2, rispettivamente. Complessivamente, i dati ottenuti indicavano un effetto biostimolante della dose 10 J/cm2 e uno bioinibitorio delle dosi 20 e 50 J∕cm2. A seguito di irradiazione singola di cellule Saos-2 sottoposte ad un protocollo di microferita in vitro per 0, 48, 96 e 144 secondi, raggiungendo rispettivamente dosi di 0, 5, 10 e 15 J/cm2, le cellule irradiate presentavano una maggiore capacità di guarigione rispetto a quelle non irradiate. La dose 15 J/cm2 risultava però meno stimolante, suggerendo una sua ridotta capacità di indurre la guarigione. Complessivamente, i dati ottenuti indicavano che il laser fosse in grado di stimolare la guarigione di microferite in vitro agendo principalmente su migrazione cellulare e deposizione di collagene.The modulation of the biological processes underlying bone remodeling by low-level laser irradiation is a highly promising strategy because it is easy to administrate, noninvasive and safe. Several parameters of laser irradiation have been proposed and this makes it difficult to obtain unambiguous clinical guidelines. The aim of the present study was to in vitro apply a wide range of doses in order to identify the laser settings responsible for biostimulatory or bioinhibitory effects on Saos-2 human osteoblast-like cells by means of morphology, viability, DNA synthesis analyses and release of relevant key molecules affecting bone remodeling and neoangiogenesis. The maximally biostimulating doses were also used in an in vitro scratch-wound healing assay in order to analyze the influence of laser irradiation on the migration and proliferation of osteoblast-like cells and to evaluate modulation by laser irradiation of cell viability, DNA synthesis, differential gene expression and release of bone metabolism related proteins. The viability of Saos-2 cells was modulated in a dose-dependent manner by a single GaAlAs laser irradiation (915 nm) for 10, 48, 96, 193 e 482 seconds reaching doses of 1, 5, 10, 20 e 50 J∕cm2, respectively. A dose of 10 J∕cm2 induced a biostimulatory cell response whereas doses of 20 or 50 J∕cm2 determined a bioinhibitory effect. After a single irradiation for 0, 48, 96 e 144 seconds reaching doses of 0, 5, 10, e 15 J∕cm2, respectively, laser significantly improved wound healing compared with non-irradiated controls. The 15 J∕cm2 laser-irradiated group showed a tendency toward increased wound area compared with that of other laser-treated groups at each experimental time, suggesting a decreased healing ability for this dose. Laser irradiation at 915 nm promoted wound healing mainly through stimulation of cell migration and collagen deposition by osteoblasts

Unusual Presentation of Juvenile Rhabdomyosarcoma in the Temporomandibular Area: A Case Report

Rhabdomyosarcoma frequently affects the craniofacial region with a rapid growing pattern that usually results in swelling of the interested area. The present paper describes a peculiar occurrence of rhabdomyosarcoma in a 12-year-old boy and the importance of a careful evaluation of clinical history to choose the correct diagnostic strategy. The patient was evaluated in the orthodontics section of the Dental School of the University of Bologna by an orofacial pain specialist, with a compliance of excruciating pain around the right ear that occurred 4 months earlier after a sports trauma. The patient had been previously evaluated by a pediatrician and an ENT specialist who requested a computerized tomography that did not show pathological conditions in the head/neck district. The drug therapy for pain control was not effective. The clinical examination showed a severe limitation of mouth opening, periauricular paresthesia and mandibular hyperalgesia on the right side. The patient reported intermittent, very intense stabs of pain occurring every 5 min, with a continuous dull pain in the temporal area. A nuclear magnetic resonance was requested and showed the presence of a solid expansive lesion in the right pterygoid area that eroded the cranial base and the medial portion of the mandibular condyle. An incisional biopsy led to the diagnosis of embryonal rhabdomyosarcoma. This case report emphasizes the importance of not underestimating the presence of pain in young subjects, suggesting a proper approach to apparently simple clinical cases

Effect of fixed orthodontic appliances on salivary properties

Objective. The purpose of this study was to evaluate the effect of fixed orthodontic appliances on the salivary flow rate, pH and buffer capacity after 1 year from bracket placement. Material and methods.The study population consisted of 20 healthy patients (mean age 16.5 \ub1 4 years) scheduled for fixed orthodontic treatment. Salivary samples were taken just before bracket placement (T0; baseline assessment) and after 1 year of treatment (T1; treatment assessment) using the GC Saliva-Check Kit (GC Corp., Belgium). Results. No statistically significant differences were detected for all the examined salivary properties between T0 and T1. Conclusions. Fixed orthodontic appliances did not have any effect on the flow rate, pH and buffer capacity of saliva after 1 year of fixed orthodontic treatment in the study sample

The Effect of Different Archwires on Initial Orthodontic Pain Perception: A Prospective Controlled Cohort Study

The early stages of orthodontic treatment are frequently associated with pain that can vary in intensity and duration, representing one of the main reasons for treatment discontinuation. Whilst the use of drugs is recognised as being effective to control orthodontic pain, there are no reliable data indicating the best first archwire for efficacy and minimum discomfort. A prospective controlled cohort study was conducted to compare the intensity and the characteristics of orthodontic pain during the first 15 days of treatment with 2 archwires. Fifty subjects were enrolled and divided into two groups: one received 0.012 inch stainless steel (SS) as the first archwire; the other, a 0.014 inch super-elastic nickel–titanium (Ni-Ti) archwire. Patients compiled a visual analogue scale to measure pain intensity over 15 days, a questionnaire for pain characteristics, the Somatosensory Amplification Scale and the State-Trait Anxiety Inventory to control the psychosocial component of pain. Dental casts were digitally analysed to evaluate the initial arch length discrepancy. In the first 3 days of treatment, the mean VAS values of the SS group were significantly lower than those of the Ni-Ti group (p < 0.05). No significant differences emerged between the groups concerning pain characteristics. The 0.012 inch SS archwire could be used at the beginning of orthodontic treatment to minimise pain perception and improve compliance

The Effect of Bite Raise on AHI Values in Adult Patients Affected by OSA: A Systematic Review with Meta-Regression

Obstructive sleep apnea (OSA) is a highly prevalent sleep breathing disorder characterized by the collapse of the pharyngeal walls that entails recurrent episodes of cessation of breathing or decrease in airflow while sleeping. This results in sleep fragmentation, decreased oxygen saturation and an increase in the partial pressure of carbon dioxide, causing excessive daytime sleepiness, hypertension and increased prevalence of cardiovascular morbidity and mortality. Mandibular advancement devices (MAD) represent a valid alternative therapy to Continuous Positive Airway Pressure, thrusting the mandible forward, increasing the lateral diameter of the pharynx and reducing the collapsibility of the airway. Several investigations have focused on the detection of the best mandibular advancement amount in terms of effectiveness and tolerance, but few and contrasting data are available on the role of occlusal bite raise in reducing the apnea/hypopnea index (AHI). The aim of this systematic review with meta-regression analysis was to investigate the effect of the bite raise of MAD on AHI values in adult patients affected by OSA. An electronic search was performed in MEDLINE, the Cochrane Database, Scopus, Web of Science and LILACS. Randomized controlled trials (RCT) investigating the effectiveness of MAD in OSA patients were included. The quality of evidence was evaluated with the Grading of Recommendations Assessment, Development and Evaluation (GRADE) and the risk of bias with the Cochrane risk-of-bias tool for randomized trials (RoB2). Six RCT were included. The success rate of each study was computed: (mean baseline AHI − mean post treatment AHI)/mean baseline AHI. The GRADE scores indicated that the quality of evidence was very low. The meta-regression analysis showed that there was no correlation between the occlusal bite raise and the AHI improvement

Prevalence of temporomandibular disorders in adult obstructive sleep apnoea patients: A cross-sectional controlled study

Background: Obstructive sleep apnoea (OSA) is characterised by partial or complete obstruction of the upper airways during sleep and it has been associated with temporomandibular disorders (TMDs) on the basis of several pathophysiological hypotheses. Objectives:To assess the prevalence of TMDs in a population of patients affected by OSA compared to a control group of subjects not affected by OSA. MethodsA cross-sectional controlled study was conducted on a group subjects studied by polygraphy (PG) at the snoring section of the ENT department, Sant'Orsola-Malpighi Hospital - University of Bologna. Patients who received a diagnosis of OSA were included in the study group and subjects with a negative PG diagnosis for Sleep Disordered Breathing and PG respiratory pattern that did not suggest the occurrence of sleep disorders were enrolled in the control group. Both the subjects included in the study group and the control group underwent an examination following the Diagnostic Criteria for Temporomandibular Disorders Axis I and II. Results: Forty-three OSA patients (29 M, 16 F, mean age 52.26 +/- 11.40) and 43 healthy controls (25 M, 18 F, mean age 49.95 +/- 7.59) were included in the study. No significant differences were found between groups in demographic data. TMD prevalence and Axis II results did not differ between groups. Conclusions: This paper does not highlight a higher prevalence of TMDs in adults with OSA compared to healthy controls. Further high-quality studies are needed to confirm the results and to give possible pathophysiological explanations, providing reliable evidence

Effect of orthopedic and functional orthodontic treatment in children with obstructive sleep apnea: A systematic review and meta-analysis

: Orthodontic treatment is suggested in growing individuals to correct transverse maxillary deficiency and mandibular retrusion. Since, as a secondary effect, these orthodontic procedures may improve pediatric obstructive sleep apnea (OSA), this systematic review assessed their effects on apnea-hypopnea index (AHI) and oxygen saturation (SaO2). Twenty-five (25) manuscripts were included for qualitative synthesis, 19 were selected for quantitative synthesis. Five interventions were analyzed: rapid maxillary expansion (RME, 15 studies), mandibular advancement (MAA, five studies), myofunctional therapy (MT, four studies), and RME combined with MAA (one study). RME produced a significant AHI reduction and minimum SaO2 increase immediately after active treatment, at six and 12 months from baseline. A significant AHI reduction was also observed six and 12 months after the beginning of MAA treatment. MT showed positive effects, with different protocols. In this systematic review and meta-analysis of data from mainly uncontrolled studies, interceptive orthodontic treatments showed overall favorable effects on respiratory outcomes in pediatric OSA. However, due to the low to very low level of the body evidence, this treatment cannot be suggested as elective for OSA treatment. An orthodontic indication is needed to support this therapy and a careful monitoring is required to ensure positive improvement in OSA parameters

Sleep Bruxism and Orofacial Pain in Patients with Sleep Disorders: A Controlled Cohort Study

Background: The gold standard for the diagnosis of sleep bruxism (SB) is laboratory polysomnography (L-PSG) recording. However, many clinicians still define SB using patients' self-assessment and/or clinical tooth wear (TW). The purpose of this cross-sectional controlled study was to compare the prevalence of TW, head-neck muscles sensitivity and Temporomandibular Disorders (TMD) between SB and non-SB patients diagnosed with L-PSG in a cohort of patient with sleep disorders (SD). Methods: 102 adult subjects with suspected SD underwent L-PSG recording to assess the presence of sleep disorder and SB. TW was clinically analyzed using TWES 2.0. The pressure pain threshold (PPT) of masticatory muscles were assessed using a Fisher algometer. Diagnostic criteria for TMD (DC/TMD) were used to evaluate the presence of TMD. SB self-assessment questionnaires were administered. TWES score, PPT, TMD prevalence and questionnaire results were compared between SB and non-SB patients. Results: 22 SB patients and 66 non-SB patients with SD were included. No significant differences emerged between groups in regards to TW, the PPT values, or SB's self-assessment questionnaires as well the prevalence of TMD. Conclusion: in a SD population, TW is not pathognomonic of active SB and SB self-assessment is not reliable. There seems to be no correlation between SB, TMD and head/neck muscle sensitivity

Oral appliances for obstructive sleep apnea

Importance: Obstructive sleep apnea (OSA) is a major public health issue that can have serious medical consequences. Although continuous positive airways pressure (CPAP) is currently the first-line treatment for OSA, there is increasing evidence on the effectiveness of oral appliances (OAs) which show higher treatment adherence compared with CPAP. This review focuses on indications, effectiveness and side effects of treatment with OAs in adult OSA patients. The role of dentists in the multidisciplinary diagnosis and management of OSA is also discussed and the most up-to-date scientific evidence for an evidence-based clinical decision-making process is summarized. Observations: Qualified dentists in dental sleep medicine can screen patients for OSA using questionnaires and evaluating the presence of anatomic risk factors during routine examinations. Sleep physicians confirm the diagnosis of OSA, determine whether treatment is indicated and may recommend OAs. Qualified dentists evaluate patients for suitability of OAs and begin therapy with the proper device. A collaborative follow-up should be performed during treatment, with patients being periodically monitored by sleep physicians for objective sleep testing and, also, by qualified dentists for OA adjustment and management of any side effect. Conclusion and Relevance: Custom-made and titratable OAs are indicated for adult OSA patients who do not tolerate or who are not good candidates for CPAP. A multidisciplinary approach allows to establish the least possible amount of mandibular advancement while achieving the highest reduction of OSA severity, thus optimizing the treatment effectiveness, reducing the occurrence of side effects and decreasing the risk of treatment discontinuation

Die Anwendung von Protrusionsschienen zur Behandlung des obstruktiven Schlafapnoe-Syndroms bei erwachsenen Patienten The use of oral appliances in the treatment of obstructive sleep apnea syndrome in adult patients

Obstructive sleep apnea (OSA) is characterized by repetitive episodes of complete or partial closure of the upper airway during sleep leading to sleep fragmentation and oxygen desaturation. This sleep-related breathing disorder is associated with daytime sleepiness, impaired quality of life, poor work performance, neurocognitive decline, increased risk of motor vehicle accidents and, in the long term, an increased risk of cardio-vascular disease and mortality. Nasal continuous positive airway pressure (nCPAP) maintains a positive pressure in the upper airway through a nose mask worn during sleep and is currently the most effective treatment option for OSA patients. Nevertheless, adherence to this therapy is low. The availability of alternative treatment options is therefore of the utmost importance. Mandibular advancement devices (MADs), which hold the mandible forward with the aim of preventing collapse of the upper airway during sleep provide a less invasive, more comfortable, and less costly treatment alternative for patients with mild to moderate OSA who do not tolerate, do not respond to, or are not appropriate candidates for treatment with nCPAP. Forward repositioning of the mandible increases the upper airway volume, widens the lateral dimension of the velopharynx, it stretches tongue muscles counteracting tongue's retrolapse during sleep, and it moves the hyoid bone anteriorly and stabilizes epiglottis and soft palate preventing the posterior rotation of the jaw. The therapy with a mandibular advancement device (MAD) represents a treatment option to obtain this anterior jaw repositioning. In this article, we will review the indications, the efficacy, the role in the clinical practice and the adverse effects of MADs for the management of OSA