Cortical and cancellous bone in mandibular symphysis: implications in osteosynthesis and osteotomy / Hueso cortical y esponjoso en sínfisis mandibular: implicancias en osteotomía y osteosíntesis

The aim of this study was to quantify the presence of cortical and cancellous bone in the mandibular symphysis. A descriptive study was conducted using cone beam computed tomography where skeletal class I and class III subjects were included, defined according to characteristics detected on dental, clinical and dental occlusion x-rays. From the 3D reconstruction, sections were used in relation to the axial axis of the teeth of the anterior sector; the amount of buccal cortical, cortical, lingual, inferior cortical and cancellous bone as well as symphysis height were determined. The measurements were taken using routine methods and analyzed with ANOVA and Tukey's HSD test with p <0.05 for statistical significance. 20 skeletal class I subjects aged 23 years (± 4.5) and 20 class III subjects aged 22 years (± 5.2) were included. Symphysis height was significantly greater in skeletal class III subjects, exceeding by 0.8 mm the height of class I subjects; the buccal cortical bone presented on average 2 mm less at different dental levels, whereas the lingual cortical and inferior basal bones were significantly larger than the buccal cortical bone. The cancellous and cortical bones did not present any significant differences between the two groups (p=0.093). The buccal and basilar cortical bone is smaller than lingual cortical bone.

El objetivo fue determinar la presencia de hueso cortical y esponjoso en sínfisis mandibular. Se realizó un estudio descriptivo en tomografías computadorizadas cone beam donde se analizaron sujetos clase I y clase III esqueletal definidos según características dentales, clínicas y radiográficas de oclusión dental y características radiográficas. Desde la reconstrucción 3D se utilizaron cortes en relación al eje axial de los dientes del sector anterior; en ellos se determinó la cantidad de hueso cortical bucal, cortical, lingual, cortical inferior, hueso esponjoso y altura de sínfisis. Las mediciones fueron realizadas con métodos de rutina y fueron analizados con la prueba ANOVA y HDS Turkey considerando un valor de p <0.05 para considerar significancia estadística. 20 sujetos clase I esqueletal con 23 años (+ 4.5) y 20 sujetos clase III esqueletal con edad de 23 años (+ 4.5) fueron incluidos. La altura de sínfisis fue significativamente mayor en sujetos de clase III esqueletal, superando por 0.8 mm la altura de sujetos clase I; el hueso cortical bucal presento en promedio menor de 2 mm en diferentes niveles dentarios, mientras que la cortical lingual y basal inferior fueron significativamente mayor que la cortical bucal. El hueso esponjoso y hueso cortical no presentó diferencias significativas entre ambos grupos (p=0.093). La cortical bucal y basilar son menores que el hueso cortical lingual.

The use of three-dimensional cephalometric references in dentoskeletal symmetry diagnosis

OBJECTIVE: The aim of this study is to assess dentoskeletal symmetry in cone-beam computed tomography (CBCT) scans of Brazilian individuals with Angle Class I malocclusion. MATERIAL: A total of 47 patients (22 females and 25 males) aged between 11 and 16 years old (14 years) seen in a private radiology service (CIRO, Goiânia, GO, Brazil) were assessed. All CBCT scans were obtained from January, 2009 to December, 2010. Cephalometric measurements were taken by multiplanar reconstruction (axial, coronal and sagittal) using Vista Dent3DPro 2.0 (Dentsply GAC, New York, USA). Minimum, maximum, mean and standard deviation values were arranged in tables, and Student t-test was used to determine statistical significance (P < 0.05). RESULTS: Data were homogeneous, and differences between the right and left sides were not significant. CONCLUSIONS: Cephalometric measurements of Brazilian individuals with Angle Class I malocclusion can be used to establish facial symmetry and three-dimensional standard references which might be useful for orthodontic and surgical planning. .

OBJETIVO: o objetivo deste estudo é avaliar a simetria dentoesqueléticas em imagens de tomografia computadorizada de feixe cônico (TCFC) de indivíduos brasileiros com má oclusão Classe I de Angle. MÉTODOS: quarenta e sete pacientes (22 meninas e 25 meninos), com idades entre 11 e 16 anos (14 anos, em média), foram atendidos em um serviço de radiologia privado. Todas as imagens de TCFC foram adquiridas a partir de janeiro de 2009 a dezembro de 2010. Medições cefalométricas foram realizadas por reconstruções multiplanares (axial, coronal e sagital) usando o VistaDent 3D Pro 2.0 ( Dentsply GAC, Nova Iorque, EUA). O desvio-padrão mínimo, máximo e a média foram descritos em tabelas, e o teste t de Student foi utilizado para definir significância estatística (p < 0,05). RESULTADOS: os dados foram homogêneos e as diferenças entre os lados direito e esquerdo não foram significativas. CONCLUSÕES: as medidas cefalométricas de indivíduos brasileiros com má oclusão Classe I de Angle podem ser usadas para definir a simetria facial e referências de padrão tridimensional, que podem ser úteis para o planejamento ortodôntico e cirúrgico. .

Oral Benign Fibrous Histiocytoma of Chin: A Rare Case Report and Literature Review.

Fibrous histiocytoma is a benign soft tissue neoplasm that may present as a fi brous mass any-where in the human body. Th e involvement of the oral cavity is extremely rare and very few cases have been reported in the literature until date. We here report a case of benign fi brous histiocytoma localized in the oral cavity in mandibular chin region and the treatment approach that need to be followed for such cases. Th e clinical and histological features of the lesion are discussed precisely in the light of a literature review of this pathology occurring in soft tissues in the head and neck region.

Dental and skeletal components of Class II open bite treatment with a modified Thurow appliance

INTRODUCTION: Due to the lack of studies that distinguish between dentoalveolar and basal changes caused by the Thurow appliance, this clinical study, carried out by the School of Dentistry - State University of São Paulo/Araraquara, aimed at assessing the dental and skeletal changes induced by modified Thurow appliance. METHODS: The sample included an experimental group comprising 13 subjects aged between 7 and 10 years old, with Class II malocclusion and anterior open bite, and a control group comprising 22 subjects similar in age, sex and mandibular plane angle. Maxillary/mandibular, horizontal/vertical, dental/skeletal movements (ANS, PNS, U1, U6, Co, Go, Pog, L1, L6) were assessed, based on 14 landmarks, 8 angles (S-N-ANS, SNA, PPA, S-N-Pog, SNB, MPA, PP/MPA, ANB) and 3 linear measures (N-Me, ANS-Me, S-Go). RESULTS: Treatment caused significantly greater angle decrease between the palatal and the mandibular plane of the experimental group, primarily due to an increase in the palatal plane angle. ANB, SNA and S-N-ANS angles significantly decreased more in patients from the experimental group. PNS was superiorly remodeled. Lower face height (ANS-Me) decreased in the experimental group and increased in the control group. CONCLUSIONS: The modified Thurow appliance controlled vertical and horizontal displacements of the maxilla, rotated the maxilla and improved open bite malocclusion, decreasing lower facial height. .

INTRODUÇÃO: devido ao número reduzido de estudos que distinguem entre as mudanças dentoalveolares e ósseas produzidas pelo aparelho de Thurow, esse estudo clínico, conduzido pelo departamento de Ortodontia da Faculdade de Odontologia de Araraquara, foi proposto para avaliar as mudanças dentárias e esqueléticas induzidas pelo aparelho de Thurow modificado. MÉTODOS: a amostra incluiu um grupo experimental de 13 indivíduos, entre 7 e 10 anos de idade, com má oclusão Classe II e mordida aberta anterior, e um grupo controle de 22 indivíduos, com idades, plano mandibular e má oclusão similares. Com base em 14 pontos cefalométricos, 8 ângulos (S-N-ANS, SNA, PPA, S-N-Pog, SNB, MPA, PP/MPA, ANB) e 3 medidas lineares (N-Me, ANS-Me, S-Go), foram avaliados movimentos maxilares e mandibulares horizontais e verticais dentários e esqueléticos (ANS, PNS, U1, U6, Co, Go, Pog, L1, L6). RESULTADOS: o tratamento produziu diminuição significativamente maior no ângulo entre o plano palatino e o plano mandibular do grupo controle, devido ao aumento do ângulo do plano palatino. Os ângulos A-N-B, S-N-A e S-N-ANS diminuíram significativamente mais no grupo tratado. A PNS sofreu remodelação superior. A altura facial inferior (ANS-Me) diminuiu no grupo tratado, ao passo que aumentou no grupo controle. CONCLUSÕES: o aparelho controlou deslocamento vertical e horizontal da maxila, rotacionou a maxila para melhorar a mordida aberta e diminuiu a altura facial inferior. .

Rare foreign bodies in oro-facial regions.

Accidental entry of foreign bodies into the oro-facial region could be due to trauma, therapeutic interventions or iatrogenic. Various foreign bodies and locations have been reported, for example, wood in the orbit, impression material in the maxillary sinus, tooth fragments in the orbit. All these cases presented with inflammatory reaction and formation of infected granuloma, pus discharging sinus and serious complications like intra-cranial abscesses. Foreign bodies sometimes migrate within the tissues and become symptomatic after a certain period of time. In these cases, it is very difficult to correlate the direct relation between the suspected foreign bodies with the present clinical symptoms. The removal of foreign bodies is often a surgical challenge due to a combination of difficulty in access and close anatomical relationship to vital structures. To prevent complications, foreign bodies should be diagnosed and removed on time.

Masseter muscle thickness in different skeletal morphology: An ultrasonographic study.

Background: The thickness of the masseter muscle during relaxation and contraction states was measured by ultrasonography. Subjects were classified according to their sagittal skeletal relationships. The association between muscle thickness and facial morphology was studied. Context: Masseter muscle thickness influences the skeletal patterns. Aim: To measure and compare the thickness of the masseter muscle in individuals with skeletal class I occlusion and skeletal class II malocclusions and to correlate its relationship with craniofacial morphology. Settings and Design: The study was conducted in a hospital setup and was designed to study the thickness of the masseter muscle in different skeletal morphologies. Materials and Methods: Seventy two individuals between the ages of 18 and 25 years were divided into Group I, Group IIA and Group IIB according to their skeletal relationships. Masseter muscle thickness was measured by ultrasonography. Eight linear and six angular cephalometric measurements were assessed. Statistical Analysis Used: Analysis of variance and Pearson's correlation analysis. Results: There was a statistically significant difference in muscle thickness between subjects of different skeletal patterns. Significant positive correlation between masseter muscle thickness and posterior total face height, jarabak ratio, ramus height, mandibular length and significant negative correlations with mandibular plane angle, gonial angle and PP-MP angle were observed. Conclusion: This study indicates the strong association between the masseter muscle and skeletal morphology.

Long term results of mandibular distraction.

Mandibular distraction osteogenesis has become a popular surgical modality due to its many advantages over conventional orthognathic surgical procedures. However, in spite of the technique having been used for over 15 years, no concrete long term results are available regarding the stability of results. We discuss the various studies which have reported either in favour or against the stablility of results after distraction. We report a series of 6 cases (3 unilateral and 3 bilateral distraction) where distraction was carried out before puberty and followed them up to seven years after removal of distractors. This case series shows that results achieved by distraction osteogenesis are unstable or best unpredictable with respect to producing a permanent size increase in the mandible. The role of the distraction osteogenesis in overcoming the pterygomassetric sling is questionable. We suggest a multicenter study with adequate patient numbers treated with a similar protocol and documented after growth cessation to have meaningful conclusions on the debate of distraction osteogenesis versus orthognathic surgery.

Intraosseous schwannoma of mandibular symphysis: case report

Schwannoma (neurilemmoma) is a benign neoplasm originated from the neural sheath and occurring most frequently in the head and neck. Intraosseous schwannomas are rare. The mandible is the most common site of occurrence for these lesions. This article reports the case of an intraosseous schwannoma located in the mandibular symphysis of an 11-year-old boy. The lesion was surgically removed and no radiographic evidence of recurrence was observed after 5 years.

O schwannoma (neurilemoma) é um neoplasma benigno que se origina da bainha neural e ocorre mais freqüentemente na cabeça e pescoço. Schwannomas intra-ósseos são raros. O local mais comumente afetado é a mandíbula. Este artigo documenta um caso de schwannoma intra-ósseo localizado na sínfise mandibular de um menino com 11 anos de idade. A lesão foi removida cirurgicamente e não houve evidências radiográficas de recorrência após 5 anos de acompanhamento.

Fístula odontogénica / Odontogenic cutaneous sinus tract

La fistula odontogénica es una patología que se expresa habitualmente como un nódulo crónico con episodios de superación intermitente localizado en cara. Su sospecha clínica permitirá su diagnóstico. La detección y el tratamiento de la causa que la originó resolverá el cuadro. Se presenta una paciente con fistula odontogénica de cinco meses de evolución al momento de la consulta dermatológica, en quien un correcto examen de su cavidad bucal permitió diagnosticar y tratar el absceso dentoalveolar que la había originado con resolución del cuadro

Cambios pronósticos del tejido blando Nasolabiomentoniano en función de los ocurridos en el componente dental del síndrome de mordida abierta anterior / Prognostic changes of the naso-labio mental soft tissue in function of the ones occurred in the dental component of anterior open bite syndrome

Se realizó una investigación retrospectiva de 46 pacientes operados del síndrome de mordida abierta anterior en el Serivicio de Cirugía Maxilofacial del Hospital Provincial Docente "Saturnino Lora" de Santiago de Cuba durante 1985-1991, con el propósito de determinar los cambios ocurridos en el tejido blando del complejo nasolabiomentoniano en función de los producidos en el componente dental durante la corrección quirúrgica de esta entidad