Pediatric maxillary expansion has a positive impact on hearing? A systematic review and meta-analysis.

OBJECTIVE: Hearing loss is a highly prevalent condition in the pediatric population. Pediatric maxillary expansion is a widespread treatment to address transverse maxillary deficiency. First reports describing an association between improvements for patients with HL and PME initiated in the 1960s. In this systematic review and meta-analysis we aim to review the role of maxillary expansion in reducing conductive hearing loss in pediatric population. REVIEW METHODS: Pubmed (Medline), the Cochrane Library, EMBASE and Trip Database were checked. Main outcome was expressed as the difference between air-bone gap, compliance, ear volume and conductive hearing thresholds before and after treatment and the 95% confidence interval. RESULTS: A total of 10 studies (218 patients) met inclusion criteria. The pooled data in the meta-analysis under a random effects model shows a statistically significant difference of 10.57dB mean reduction after palatal expansion. The air-bone gap was significantly reduced by 5.39dB (CI 95% 3.68, 7.10). Compliance and volume were assessed in three studies, with a non-significant positive difference in the compliance (0.14) and a statistically significant difference for volume (0.80) after palatal expansion. CONCLUSION: This systematic review and meta-analysis found a positive effect of pediatric maxillary expansion in conductive hearing loss in well-select children. However, results cannot be extrapolated for children with conductive hearing loss without an accompanying orthodontic indication (maxillary constriction). It showed that the existing prospective studies exhibited qualitative pitfalls, limiting the ability to obtain conclusive evidence about the role of pediatric maxillary expansion on conductive hearing loss in children.

Cytokine-based Predictive Models to Estimate the Probability of Chronic Periodontitis: Development of Diagnostic Nomograms.

Although a distinct cytokine profile has been described in the gingival crevicular fluid (GCF) of patients with chronic periodontitis, there is no evidence of GCF cytokine-based predictive models being used to diagnose the disease. Our objectives were: to obtain GCF cytokine-based predictive models; and develop nomograms derived from them. A sample of 150 participants was recruited: 75 periodontally healthy controls and 75 subjects affected by chronic periodontitis. Sixteen mediators were measured in GCF using the Luminex 100™ instrument: GMCSF, IFNgamma, IL1alpha, IL1beta, IL2, IL3, IL4, IL5, IL6, IL10, IL12p40, IL12p70, IL13, IL17A, IL17F and TNFalpha. Cytokine-based models were obtained using multivariate binary logistic regression. Models were selected for their ability to predict chronic periodontitis, considering the different role of the cytokines involved in the inflammatory process. The outstanding predictive accuracy of the resulting smoking-adjusted models showed that IL1alpha, IL1beta and IL17A in GCF are very good biomarkers for distinguishing patients with chronic periodontitis from periodontally healthy individuals. The predictive ability of these pro-inflammatory cytokines was increased by incorporating IFN gamma and IL10. The nomograms revealed the amount of periodontitis-associated imbalances between these cytokines with pro-inflammatory and anti-inflammatory effects in terms of a particular probability of having chronic periodontitis.

In situ neutralisation of the antibacterial effect of 0.2% Chlorhexidine on salivary microbiota: Quantification of substantivity.

OBJECTIVE: To quantify the substantivity of a single 0.2% Chlorhexidine mouthwash in saliva after its neutralisation with tooth-brushing and 1% acetic acid, in order to identify the effect of Chlorhexidine substantivity in regard to the re-growing period of the salivary bacteria. METHODS: Unstimulated saliva samples were collected from a group of 15 healthy individuals at baseline (BS), and then 30s and 1, 3, 5 and 7h after the following protocols were performed: a single sterile water mouthwash (M-WATER) (negative control), a single 0.2% Chlorhexidine mouthwash (M-0.2% CHX) (positive control) and a single 0.2% Chlorhexidine mouthwash followed by a complete and detailed tooth-brushing, and a single 1% acetic acid mouthwash (M-0.2% CHX+NP). The samples were analysed using an epifluorescence microscope in combination with LIVE/DEAD(®) BacLight™ fluorescence solution. RESULTS: After the M-0.2% CHX treatment, the bacterial vitality was significantly lower than BS until 7h (87.6 ± 6.5% vs. 73.6 ± 8.8%; p<0.001). However, after M-0.2% CHX+NP, the bacterial vitality remained significantly lower until 3h with regard to BS (81.4 ± 3.8% vs. 68.1 ± 10.6%; p=0.001), increasing at 5 and 7h (no differences from BS). CONCLUSION: The immediate antibacterial effect of a single 0.2% Chlorhexidine mouthwash is so potent that the bacterial population needs more than 3h to return to baseline bacterial vitality levels. The substantivity of a 0.2% Chlorhexidine mouthwash is a property that significantly increases its antibacterial activity from the first hour and contributes to extend the duration of its effect by at least double.

Efecto del estrés sobre el movimiento dental / Effect of stress on dental movement

Introducción. Es bien conocido que la actividad remodeladora del hueso alveolar en los tejidos periodontales ocurre bajo ciertas circunstancias. Factores sistémicos pueden estar involucrados en la regulación de la actividad degradadora tisular. La reabsorción ósea es regulada por las citoquinas, que se encuentran dentro de las células medulares, que median la activación y formación de osteoclastos. Material y método. Veinticuatro ratas fueron asignadas al azar en cuatro grupos de seis ratas cada uno: grupo control, grupo estrés, grupo con movimiento dental y grupo de movimiento dental y estrés. Para ejercer la fuerza ortodóncica se utilizó un método modificado por Kohno et al. Las ratas fueron sometidas a una banda ancha de ruidos de 100 dB diarios por 5 segundos cada minuto durante períodos de 1 a 3 horas alrededor de la medianoche, en el pico de la actividad diurna. Se midió el movimiento dentario por un método modificado que fue descrito previamente por King et al (1991).Resultados. A los siete y catorce días se observó un aumento estadísticamente significativo del movimiento dental en animales sujetos a estrés comparados con aquellos no estresados. Discusión. Estudios recientes han sugerido que la regulación de la remodelación ósea puede estar influenciada por el sistema inmune a través de la producción de citoquinas por las células inflamatorias presentes tras la aplicación de fuerzas ortodóncicas. Numerosos estudios interdisciplinarios psicoinmunológicos han evidenciado que estímulos externos que generan repuestas de estrés emocional pueden influir y modular al sistema inmune por la vía del sistema nervioso y neuroendocrino (AU)

Introduction. The active remodeling of alveolar bone in periodontal tissues is well known to occur in various kinds of conditions. Systemic factors may be involved in the regulation of the tissue-degrading activity. Bone resorption is regulated by the cytokines within marrow cells that mediate osteoclast formation and activation. Psychological responses to stressors have been shown to modulate the immune system though the neural and endocrine system in at least three different pathways. Material and method. Twenty-four rats, were randomly assigned into four groups of six rats each, control, stress, dental movement, stress and dental movement. To exert orthodontic force we used a modified method described by Kohno et al. The rats were subjected to a broad band noise at 100 dB daily for 5 seconds every minute during a 1 or 3-h period around midnight, at the height of the diurnal activity cycle. Unstimulated rats were exposed only to the normal activity of the animal room. Tooth movement assessed by extra-oral cephalometric radiographic view from the superior, by a modified method that was previously described by King et al (1991).Results. At seven and fourteen days we observed a statistically significant increase of dental movement in the animals subject to stress compared to those not stressed. Discussion. Recent studies have suggested that the regulation of bone remodeling can be influenced by the immune system though cytokine production from inflammatory cells present after the application of orthodontic forces. Numerous interdisciplinary psychoimmunological studies have provided evidence that external stimuli generating emotional stress responses may influence and modulate the immune system via nervous and neuroendochrine system (AU)

Arco recto de baja fricción: sistema Synergy (1. ª parte) / Straight wire low friction: Synergy system

The SWLF is a diagnostic and therapeutic upgrade in accordance with the latest technological advances in our specialty (orthodontic practice), and combines the use of Synergy low friction brackets (RMO), superelastics and thermoelastics latest generation wires, beta III-titanium finishing wires, hooks and elastic modules to close spaces and microscrews as a means ob bone anchorage. The special design of the Synergy bracket, the new prescription SWLF and the latest generation wires facilitate easier alignment, allows the rapid rectangular arch wire fit and better wire-slot interaction. The new arch wires with their wide range of action allow us to space out patient appointments and reduce the treatment time which uses fixed apparatus. Selective friction control (CSF) is established according to the following criteria: wire selection, ligature (composition, type and design) and the placement and control hooks (crimpable­hook) which may be placement in any arch with special pliers. The technique has a series of diagnostic and therapeutic protocols and includes a clear archwires selection policy. The general philosophy of the technique is to standardize our treatments, simplifying biomechanical aspects and optimizing the biological tooth movement by appling continius and long lasting light forces. The SWLF is an attempt to bring orthodontic practice in line with the demands of patients, making shorter, faster and ergonomic treatment possible

La straight wire low friction (SWLF), representa la última generación de las técnicas de arco recto y se basa en el concepto de control selectivo de la fricción (CSF), tratando de superar los problemas derivados de la fricción estática y dinámica que acontecen en las técnicas de SW con brackets tradicionales. La SWLF es una actualización diagnóstica y terapéutica acorde con los últimos avances tecnológicos en nuestra especialidad y combina el empleo de brackets de baja fricción Synergy (RMO), alambres superelásticos y termoelásticos de última generación, alambres de terminación de beta III-titanio, postes y módulos elásticos para el cierre de espacios y microimplantes como fuente de anclaje óseo. El diseño especial del Synergy, la nueva prescripción SWLF y los alambres de última generación facilitan el alineamiento, permiten la temprana inserción de alambres rectangulares y una mejor interacción alambre-ranura. Los nuevos alambres con su amplio rango de acción nos permiten espaciar las visitas y acortar la duración del tratamiento con aparatos fijos. El control selectivo de la fricción se establece en función de la selección del alambre, la ligadura (composición, tipo y diseño) y la colocación y manejo de los postes (crimpable-hooks) que se pueden colocar en cualquier arco mediante unos alicates especiales. La técnica tiene una serie de protocolos diagnósticos y terapéuticos e incluye una clara selección de arcos de alambre. La filosofía general de la técnica es estandarizar nuestros tratamientos, simplificando la biomecánica y optimizando la biología del movimiento dentario al aplicar fuerzas ligeras, constantes y de larga duración. La SWLF pretende hacer una ortodoncia acorde con las demandas de nuestros pacientes, haciendo tratamientos más cortos rápidos y ergonómicos

Prospective evaluation of an oral appliance in the treatment of obstructive sleep apnea syndrome.

The purpose of this study was to investigate the effects of an oral appliance (OA), with and without mandible advance, in the treatment of obstructive sleep apnea syndrome (OSA). Twenty-four patients diagnosed with OSA agreed to participate in this study. The patients were treated for 3 months (with a removable soft elastic silicone positioner customized with thermoplastic silicone and with a 5-mm opening). Patients were selected, using a randomized design, to receive an OA model either with (12 patients) or without advance (12 patients). Before treatment, a snoring questionnaire, the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36), the Functional Outcomes of Sleep Questionnaire (FOSQ), the Epworth Sleepiness Scale (ESS), and polysomnography were completed. Fifteen subjects completed the protocol (13 men, two women). With respect to basal values, the mandible-advanced OA group presented a decrease in the mean apnea-hypopnea index (AHI) (33.8+/-4.7 versus 9.6+/-2.1; p<0.01), number of arousals per hour (33.8+/-13.9 versus 16.0+/-1.5; p<0.05), ESS score (14.7+/-5.1 versus 5.1+/-1.9; p<0.05), snoring score (15.4+/-1.9 versus 10.1+/-3.2; p<0.05), and total FOSQ score (78.1+/-22.6 versus 99.3+/-14.4; p<0.05). After treatment, the non-advanced group presented a decrease in the mean AHI (24.0+/-12.2 versus. 11.7+/-7.9; p<0.05). However, no significant differences were found in the number of arousals per hour, ESS score, snoring, and total FOSQ score in the non-advanced group. Neither study group showed significant difference in mean SF36 scores. Oral appliances, especially those that advance the mandible, offer an effective treatment for OSA.

Diastemas in primary dentition and their relationships to sex, age and dental occlusion.

AIM: The prevalence of interincisive and primate spaces in the primary dentition, relating them to age and sex, was studied. An analysis was made as to what extent various occlusal aspects of the arches affect the existence of spacing. MATERIALS AND METHODS: A population of 267 children, 153 males and 114 females, aged 2.2-8.2 years, was evaluated. All were white Caucasian, apparently healthy and lacking any congenital malformations; they had complete primary dentition and no erupted permanent teeth, without existing dental malformation and not having undergone any type of orthodontic treatment. Cast models were fabricated from impressions taken of all the children. Tooth sizes and interdental spaces were measured on these models and the various occlusal aspects were noted. RESULTS: The prevalence of spacing was high in the primary dentition, being independent of the chronological age of each child. Spacing was more frequent in males than in females. The presence or absence of spacing was not directly related to occlusion except in cases of posterior cross-bite, where it was less frequently, and open-bites, in which spaces appeared more often than usual. CONCLUSION: Spaces in the primary dentition were very common among the population studied and more frequent in male children than in females. Primate spaces were more frequent at the earliest ages, but chronological age had no influence on the presence of interincisive spacing. The lack of the spaces in the maxillary arches, typical of the primary dentition, prevailed among individuals with posterior cross-bite, contrary to what normally happens in the rest of the population.

The diastemas in deciduous dentition: the relationship to the tooth size and the dental arches dimensions.

Tooth size and different arch parameters were studied for influence in the presence or absence of diastemas in the primary dentition. The size of teeth scarcely influences the presence or absence of diastemas, but the dental arch dimensions are closely connected with diastemas.

Otic ganglion parasympathetic neurons innervate the pulp of the mandibular incisor of the guinea pig.

Neurons innervating the pulp of the lower incisor of the guinea pig have been traced using the fluorochrome Fast blue. Besides those located in the ipsilateral Gasser's ganglion, a small number of parasympathetic cells in the ipsilateral otic ganglion were also found to innervate the pulp (chiefly the deepest region) via the inferior alveolar nerve. This is the first anatomical evidence of the presence of parasympathetic fibers in the teeth of mammals. It is suggested that these parasympathetic neurons stimulate the vasodilation of the arterioles supplying the tooth pulp.

The postganglionic parasympathetic fibers originating in the otic ganglion are distributed in several branches of the trigeminal mandibular nerve: an HRP study in the guinea pig.

Application of HRP to the proximal stumps of the ramifications of the trigeminal nerve shows that all those belonging to the mandibular branch contain parasympathetic fibers originating in the otic ganglion. The nerve with the largest proportion of these fibers is the auriculotemporal nerve (50-60% of all labeled neurons), while the smallest percentages are found in the lingual nerve and motor root (about 5% each). The presence of otic fibers in the inferior alveolar, mylohyoid, buccal and motor branches of the trigeminal nerve has not hitherto been reported.