Mutations in the latent TGF-beta binding protein 3 (LTBP3) gene cause brachyolmia with amelogenesis imperfecta.

Inherited dental malformations constitute a clinically and genetically heterogeneous group of disorders. Here, we report on four families, three of them consanguineous, with an identical phenotype, characterized by significant short stature with brachyolmia and hypoplastic amelogenesis imperfecta (AI) with almost absent enamel. This phenotype was first described in 1996 by Verloes et al. as an autosomal recessive form of brachyolmia associated with AI. Whole-exome sequencing resulted in the identification of recessive hypomorphic mutations including deletion, nonsense and splice mutations, in the LTBP3 gene, which is involved in the TGF-beta signaling pathway. We further investigated gene expression during mouse development and tooth formation. Differentiated ameloblasts synthesizing enamel matrix proteins and odontoblasts expressed the gene. Study of an available knockout mouse model showed that the mutant mice displayed very thin to absent enamel in both incisors and molars, hereby recapitulating the AI phenotype in the human disorder.

Increased Anxiety-Like Behavior in the Acute Phase of a Preclinical Model of Periodontal Disease.

Periodontal disease (PD) is an infectious-inflammatory oral disease that is highly prevalent among adolescence and adulthood and can lead to chronic orofacial pain and be associated with anxiety, stress and depression. This study aimed to identify anxiety-like behaviors in the ligature-induced murine preclinical model of PD in different phases of the disease (i.e., acute vs. chronic). Also, we investigated orofacial mechanical allodynia thresholds and superficial cortical plasticity along the orofacial motor cortex in both disease phases. To this aim, 25 male Wistar rats were randomly allocated in acute (14 days) or chronic (28 days) ligature-induced-PD groups and further divided into active-PD or sham-PD. Anxiety-like behavior was evaluated using the elevated plus maze, mechanical allodynia assessed using the von Frey filaments test and superficial motor cortex mapping was performed with electrical transdural stimulation. We observed increased anxiety-like behavior in active-PD animals in the acute phase, characterized by decreased number of entries into the open arm extremities [t (1,7) = 2.42, p = 0.04], and reduced time spent in the open arms [t (1,7) = 3.56, p = 0.01] and in the open arm extremities [t (1,7) = 2.75, p = 0.03]. There was also a reduction in the mechanical allodynia threshold in all active-PD animals [Acute: t (1,7) = 8.81, p < 0.001; Chronic: t (1,6) = 60.0, p < 0.001], that was positively correlated with anxiety-like behaviors in the acute group. No differences were observed in motor cortex mapping. Thus, our findings show the presence of anxiety-like behaviors in the acute phase of PD making this a suitable model to study the impact of anxiety in treatment response and treatment efficacy.

Características físicas e bucais na síndrome do X frágil: revisão de literatura / Physical and oral characteristics of fragile X syndrome: literature review

Introdução: A síndrome do cromossomo X frágil é uma síndrome genética que acomete principalmente indivíduos do sexo masculino. O nome desta síndrome ocorre como consequência de um estreitamento da extremidade distal do braço longo do cromossomo X, local chamado de sítio frágil. O presente trabalho apresenta uma revisão de literatura, apresentando etiologia, prevalência, métodos de diagnósti-co, características comportamentais, características físicas gerais e de interesse odontológico, além das considerações acerca do atendimento, realizado pelo cirurgião-dentista, em portadores da síndrome do X frágil. Revisão de literatura: As principais características comportamentais são o déficit de atenção, a dificuldade na interação social, a timidez, a ansiedade, a labilidade emocional e os movimentos este-reotipados de mãos. Os achados de interesse odontológico mais prevalentes na literatura foram palato ogival, prog-natismo mandibular, macroglossia, hipoplasia de esmalte e má oclusão. Discussão: Não foram encontrados muitos artigos voltados para a análise facial e odontológica destes pacientes. O atendimento deste público é um desafio para o cirurgião-dentista devido às características comportamentais e fisiológicas apresentadas. Conclusão: o conhecimento das características desta síndrome pelo profissional é impor-tante, pois a síndrome comumente se associa à doenças sistêmicas que podem influenciar no plano de tratamento, além de alterações orofaciais importantes.

Introduction: The fragile X syndrome is a genetic syn-drome that mainly affects males. The name of this syn-drome occurs as a consequence of a narrowing of the distal end of the long arm of the X chromosome, a site called the fragile site. This paper presents a review of the literature, presenting etiology, prevalence, diagnostic methods, behavioral characteristics, general physical characteristics and dental interest, as well as considera-tions about the care provided by the dentist in patients with fragile X syndrome. Literature review: The main behavioral characteristics are attention deficit, difficulty in social interaction, shyness, anxiety, emotional lability and stereotyped hand movements. The most prevalent findings of dental interest in the literature were the ogival palate, mandibular prognathism, macroglossia, enamel hypoplasia and malocclusion. Discussion: There were not many articles focused on facial and dental analysis of these patients. The care of this public is a challenge for the dentist due to the behavioral and physiological characteristics presented. Conclusion: professional know-ledge of the characteristics of this syndrome is important, as the syndrome is commonly associated with systemic diseases that may influence the treatment plan, as well as major orofacial changes.

Oral mucositis prevention by low-level laser therapy in head-and-neck cancer patients undergoing concurrent chemoradiotherapy: a phase III randomized study.

PURPOSE: Oral mucositis is a major complication of concurrent chemoradiotherapy (CRT) in head-and-neck cancer patients. Low-level laser (LLL) therapy is a promising preventive therapy. We aimed to evaluate the efficacy of LLL therapy to decrease severe oral mucositis and its effect on RT interruptions. METHODS AND MATERIALS: In the present randomized, double-blind, Phase III study, patients received either gallium-aluminum-arsenide LLL therapy 2.5 J/cm(2) or placebo laser, before each radiation fraction. Eligible patients had to have been diagnosed with squamous cell carcinoma or undifferentiated carcinoma of the oral cavity, pharynx, larynx, or metastases to the neck with an unknown primary site. They were treated with adjuvant or definitive CRT, consisting of conventional RT 60-70 Gy (range, 1.8-2.0 Gy/d, 5 times/wk) and concurrent cisplatin. The primary endpoints were the oral mucositis severity in Weeks 2, 4, and 6 and the number of RT interruptions because of mucositis. The secondary endpoints included patient-reported pain scores. To detect a decrease in the incidence of Grade 3 or 4 oral mucositis from 80% to 50%, we planned to enroll 74 patients. RESULTS: A total of 75 patients were included, and 37 patients received preventive LLL therapy. The mean delivered radiation dose was greater in the patients treated with LLL (69.4 vs. 67.9 Gy, p = .03). During CRT, the number of patients diagnosed with Grade 3 or 4 oral mucositis treated with LLL vs. placebo was 4 vs. 5 (Week 2, p = 1.0), 4 vs. 12 (Week 4, p = .08), and 8 vs. 9 (Week 6, p = 1.0), respectively. More of the patients treated with placebo had RT interruptions because of mucositis (6 vs. 0, p = .02). No difference was detected between the treatment arms in the incidence of severe pain. CONCLUSIONS: LLL therapy was not effective in reducing severe oral mucositis, although a marginal benefit could not be excluded. It reduced RT interruptions in these head-and-neck cancer patients, which might translate into improved CRT efficacy.

Efficacy of low-level laser therapy and aluminum hydroxide in patients with chemotherapy and radiotherapy-induced oral mucositis.

This study evaluated the efficacy of low-level laser therapy (LLLT) and aluminum hydroxide (AH) in the prevention of oral mucositis (OM). A prospective, comparative and non-randomized study was conducted with 25 patients with head and neck cancer subjected to radiotherapy (RT) or radiochemotherapy (RCT). Twelve patients received LLLT (830 nm, 15 mW, 12 J/cm²) daily from the 1st day until the end of RT before each sessions during 5 consecutive days, and the other 13 patients received AH 310 mg/5 mL, 4 times/day, also throughout the duration of RT, including weekends. OM was measured using an oral toxicity scale (OTS) and pain was measured using the visual analogue scale (VAS). EORTC questionnaires were administered to the evaluate impact of OM on quality of life. The LLLT group showed lower mean OTS and VAS scores during the course of RT. A significant difference was observed in pain evaluation in the 13th RT session (p=0.036). In both groups, no interruption of RT was needed. The prophylactic use of both treatments proposed in this study seems to reduce the incidence of severe OM lesions. However, the LLLT was more effective in delaying the appearance of severe OM.

Efficacy of low-level laser therapy and aluminum hydroxide in patients with chemotherapy and radiotherapy-induced oral mucositis

This study evaluated the efficacy of low-level laser therapy (LLLT) and aluminum hydroxide (AH) in the prevention of oral mucositis (OM). A prospective, comparative and non-randomized study was conducted with 25 patients with head and neck cancer subjected to radiotherapy (RT) or radiochemotherapy (RCT). Twelve patients received LLLT (830 nm, 15 mW, 12 J/cm²) daily from the 1st day until the end of RT before each sessions during 5 consecutive days, and the other 13 patients received AH 310 mg/5 mL, 4 times/day, also throughout the duration of RT, including weekends. OM was measured using an oral toxicity scale (OTS) and pain was measured using the visual analogue scale (VAS). EORTC questionnaires were administered to the evaluate impact of OM on quality of life. The LLLT group showed lower mean OTS and VAS scores during the course of RT. A significant difference was observed in pain evaluation in the 13th RT session (p=0.036). In both groups, no interruption of RT was needed. The prophylactic use of both treatments proposed in this study seems to reduce the incidence of severe OM lesions. However, the LLLT was more effective in delaying the appearance of severe OM.

Este estudo avaliou a eficácia da terapia do laser de baixa potência (LBP) e hidróxido de alumínio (HA) na prevenção da mucosite oral (MO). Um estudo prospectivo, comparativo e não-aleatorizado foi conduzido com 25 pacientes com câncer de cabeça e pescoço submetidos a radioterapia (RT) ou radioquimioterapia (RT/QT). Doze pacientes receberam LBP (830 nm, 15 mW, 12 J/cm²) diariamente desde o primeiro dia até o final da RT antes de cada sessão durante 5 dias consecutivos, e os outros 13 pacientes receberam HA 310 mg/5 mL, 4 vezes ao dia, também por toda a duração da RT, incluindo finais de semana. MO foi mensurada usando uma escala de toxicidade oral (ETO) e dor foi mensurada usando a escala visual analógica (EVA). Questionários da EORTC foram administrados para a avaliação do impacto da MO na qualidade de vida. O grupo LBP mostrou menores médias dos escores da ETO e EVA durante o curso da RT. Uma diferença significante foi observada na avaliação da dor na 13ª sessão de RT (p=0,036). Em ambos os grupos, nenhuma interrupção da RT foi necessária. O uso profilático de ambos os tratamentos propostos neste estudo parece reduzir a incidência de lesões severas de MO. No entanto, o LBP foi mais efetivo no atraso do aparecimento da MO severa.