Abstract Objectives: Odontogenic infections are frequent and can spread, leading to complications such as sepsis and the need for admission to an Intensive Care Unit (ICU). The purpose of this study was to perform a computed tomography analysis of the fascial space involvement and correlate with personal data, laboratory tests, length of hospital stays and admission to the ICU in patients with odontogenic infections who required hospitalization. Methods: Patients with odontogenic infections admitted between June 2017 and May 2018 were prospectively evaluated. The fascial spaces involved were studied using computed tomography with contrast. The possible correlations of tomographic findings with comorbidities, nutritional status, the causative tooth, laboratory tests, length of hospital stays and admission to the ICU were analyzed. Results: We identified 66 cases of odontogenic infections which were admitted in the period analyzed. The involvement of primary spaces (86.7%) predominated, followed by secondary ones (8.7%), and cervical (4.6%). The most frequently involved fascial spaces were submandibular (27.1%), buccal (20.8%), sublingual (18.3%), submental (16.7%), and others (17.1%). There were significant differences between laboratory tests (p < 0.001), mean hospital stays (p < 0.001), and admissions to the ICU (p < 0.001) depending on the number of fascial spaces involved. There was no influence of comorbidities, nutritional status, or causative tooth on fascial space involvement. Conclusion: There was a relationship between greater involvement of fascial spaces assessed by computed tomography and higher values of laboratory tests, more extended hospitalization stays and admission to the ICU. Level of evidence: Level 2b.

Aim To describe cone-beam computed tomography (CBCT) features in patients with temporomandibular disorders (TMDs), in terms of degenerative changes, condylar excursions and positioning as well as their possible correlations with signs and symptoms. Methods Clinical records of patients diagnosed with TMD who were seen between January 2018 and December 2019 were retrospectively evaluated. These patients were divided into the following groups based on the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD): arthralgia, myalgia, and arthralgia and myalgia groups. The CBCT examination findings of the patients were evaluated in relation to degenerative changes, estimates of condylar excursion, and condylar positioning. The likelihood ratio test was used to verify the possible differences among the three groups, whereas the chi-square test was used to verify the possible differences among the signs and symptoms for the tomographic findings (p ≤ 0.050). Results In this study, 65 patients with TMD were included. These patients were predominantly female (84.6%) with a mean age of 40.6 years. Tomographic findings of flattening, hyperexcursion and posterior condylar positioning were frequent. A significant correlation was noted between osteophyte and lateral capsule pain (p = 0.027), erosion and posterior capsule pain (p = 0.026), and flattening, pseudocysts (p < 0.050) and condylar excursion (p < 0.001) with mouth opening. Conclusion Few correlations were noted between degenerative changes and signs of joint pain as well as degenerative changes and condylar hypoexcursion with mouth opening. These correlations were likely associated with division by diagnosis, whereas condylar positioning did not correlate with signs and symptoms.

ABSTRACT Purpose: to evaluate the occurrence of loss of sensitivity of the inferior alveolar nerve, and to monitor the remission of this change in patients with mandibular fractures subjected to surgical treatment. Methods: patients with mandibular fractures, surgically treated within one year, were prospectively evaluated. Data regarding etiology, fracture location, type and displacement, and surgical access, were obtained. The tactile and thermal tests were applied at eighteen points in the mental region, within a period of six months. Statistical tests were applied to compare the categories of variables and the period of observation (p ≤ 0.050). Results: during the study, 37 patients were included. There were 24 bilateral and 13 unilateral fractures. Sensory changes occurred in 56.8% of the patients in the preoperative period, in 83.8% of the patients, in the postoperative period, and 35.1% of the patients presented complete remission during the final period of the study. Conclusion: sensory changes occurred in about half of the patients, due to the fracture, increasing greatly in the postoperative period, with complete remission in about one third of the cases. The fracture type, degree of displacement and surgical access type influenced the occurrence of sensory alterations.

Introdução: o deslocamento do disco articular sem redução com abertura limitada é uma desordem intracapsular que envolve o complexo côndilo-disco. Na posição de boca fechada, o disco articular se encontra numa posição anterior em relação à cabeça da mandíbula e não sofre redução com a abertura de boca. Essa desordem está associada à abertura mandibular limitada e persistente.Caso clínico:o paciente relatava travamento da mandíbula que não permitia uma abertura completa da boca, interferindo, assim, na capacidade de se alimentar. Também era possível observar-se uma abertura assistida (alongamento passivo) com uma distância vertical menor que 40 mm entre os incisivos. A ressonância magnética foi o método de escolha para o diagnóstico das desordens temporomandibulares.Conclusão:por meio da descrição de um caso raro de deslocamento anterior do disco articular sem redução e com abertura limitada, após exodontia traumática do terceiro molar inferior, em que foi realizada a redução manual do disco articular da articulação temporomandibular, provou-se ser essa uma técnica eficaz no rápido restabelecimento dos movimentos mandibulares.

Introduction: Disc displacement without reduction with limited opening is an intracapsular biomechanical disorder involving the condyle-disc complex. With the mouth closed, the disc is in an anterior position in relation to the condylar head and does not reduce with mouth opening. This disorder is associated with persistent limited mandibular opening.Case report:The patient presented severe limitation to fully open the mouth, interfering in her ability to eat. Clinical examination also revealed maximum assisted jaw opening (passive stretch) with less than 40 mm of maximum interincisal opening. Magnetic resonance imaging was the method of choice to identify the temporomandibular disorders.Conclusion: By means of reporting this rare case of anterior disc displacement without reduction with limited opening, after traumatic extraction of a mandibular third molar, in which manual reduction of temporomandibular joint articular disc was performed, it was possible to prove that this technique is effective in the prompt restoration of mandibular movements.

The purpose of this retrospective study was to evaluate contributing factors in patients requiring surgical retreatment of mandibular fractures. Of all the patients with mandibular fractures who were treated using internal fixation at a trauma hospital over a seven-year period, 20 patients (4.7%) required a second surgery and thus composed the “reoperated” group. The control group comprised 42 consecutive patients with mandibular fractures who were treated at the same clinic and who healed without complications. Medical charts were reviewed for gender, age, substance abuse history, dental condition, etiology, location of fracture, degree of fragmentation, fracture exposure, teeth in the fracture line, associated facial fractures, polytrauma, time elapsed between trauma and initial treatment, surgical approach and fixation system. Statistical analyses were performed using the Statistical Package for Social Sciences (SPSS) version 20.0; descriptive statistics and the chi-squared test were used to determine differences between groups. Significant differences in substance abuse (p = 0.006), dental condition (p < 0.001), location of fracture (p = 0.010), degree of fragmentation (p = 0.003) and fracture exposure (p < 0.001) were found. With regard to age and time elapsed between trauma and initial treatment, older patients (31.4 years, SD = 11.1) and a delay in fracture repair (19.1 days, SD = 18.7) were more likely to be associated with reoperation. It was concluded that substance abuse, age, dental condition, location of fracture, degree of fragmentation, fracture exposure and the time between trauma and initial treatment should be considered contributing factors to the occurrence of complications that require surgical retreatment of mandibular fractures.

This study analyzed the effects of unilateral detachment of the temporal muscle and coronoidotomy on facial growth in young rats. Thirty one-month-old Wistar rats were distributed into three groups: detachment, coronoidotomy and sham-operated. Under general anesthesia, unilateral detachment of the temporal muscle was performed for the detachment group, unilateral coronoidotomy was performed for the coronoidotomy group, and only surgical access was performed for the sham-operated group. The animals were sacrificed at three months of age. Their soft tissues were removed, and the mandible was disarticulated. Radiographic projections-axial views of the skulls and lateral views of hemimandibles-were taken. Cephalometric evaluations were performed, and the values obtained were submitted to statistical analyses. There was a significant homolateral difference in the length of the premaxilla, height of the mandibular ramus and body, and the length of the mandible in all three groups. However, comparisons among the groups revealed no significant differences between the detachment and coronoidotomy groups for most measurements. It was concluded that both experimental detachment of the temporal muscle and coronoidotomy during the growth period in rats induced asymmetry of the mandible and affected the premaxilla.

OBJETIVO: Avaliar a simetria facial de ratos tratados com metotrexato (MTX), em dose alta e baixa, submetidos à fratura experimental do processo condilar com desvio por meio de mensurações cefalométricas. MÉTODOS: Cem ratos Wistar machos foram submetidos a procedimento cirúrgico utilizando modelo experimental de fratura de côndilo do lado direito. Os animais foram distribuídos em quatro grupos: A - soro fisiológico (1mL/semana); B - dexametasona (DEX) (0,15mg/Kg); C - MTX baixa dose (3mg/Kg/semana); D - MTX alta dose (30mg/Kg). Os períodos de sacrifício foram de 1, 7, 15, 30 e 90 dias de pós-operatório (n=5). O peso dos animais foi documentado. Foram realizadas mensurações lineares da maxila e da mandíbula, bem como angulares do desvio mandibular. Os dados foram submetidos a análises estatísticas entre os grupos, períodos de sacrifício e entre os lados em cada grupo (α=0,05). RESULTADOS: Os animais recuperaram peso ao longo do tempo, exceto no grupo D. Houve redução no comprimento mandibular com alterações também na maxila e desvio progressivo da mandíbula em relação à base do crânio no grupo D. CONCLUSÃO: O tratamento com metotrexato em alta dose teve efeito deletério na simetria facial de ratos submetidos à fratura do processo condilar.

PURPOSE: To investigate the facial symmetry of high and low dose methotrexate (MTX) treated rats submitted to experimentally displaced mandibular condyle fracture through the recording of cephalometric measurements. METHODS: One hundred male Wistar rats underwent surgery using an experimental model of right condylar fracture. Animals were divided into four groups: A - saline solution (1mL/week); B - dexamethasone (DEX) (0,15mg/Kg); C - MTX low dose (3 mg/Kg/week); D - MTX high dose (30 mg/Kg). Animals were sacrificed at 1, 7, 15, 30 and 90 days postoperatively (n=5). Body weight was recorded. Specimens were submitted to axial radiographic incidence, and cephalometric mensurations were made using a computer system. Linear measurements of skull and mandible, as well as angular measurements of mandibular deviation were taken. Data were subjected to statistical analyses among the groups, periods of sacrifice and between the sides in each group (α=0.05). RESULTS: Animals regained body weight over time, except in group D. There was reduction in the mandibular length and also changes in the maxilla as well as progressive deviation in the mandible in relation to the skull basis in group D. CONCLUSION: Treatment with high dose methotrexate had deleterious effect on facial symmetry of rats submitted to experimentally displaced condylar process fracture.

OBJETIVO: Investigar a simetria facial de ratos submetidos à fratura experimental de côndilo mandibular e com desnutrição protéica (8% de proteína) por meio de mensurações cefalométricas. MÉTODOS: 45 ratos Wistar adultos foram distribuídos em três grupos: grupo fraturado, submetido a fratura condilar sem alteração na dieta; grupo fraturado desnutrido, submetido a dieta hipoprotéica e fratura condilar; grupo desnutrido, mantido até o final do experimento, sem fratura condilar. Fraturas com desvio foram feitas no côndilo direito com anestesia geral. Os espécimes foram submetidos à incidência radiográfica axial, e mensurações cefalométricas foram feitas por meio de um sistema de computador. Os valores obtidos foram submetidos a análises estatísticas entre os grupos e entre os lados em cada grupo. RESULTADOS: Houve redução significante nos valores de proteínas séricas e de albumina no grupo fraturado desnutrido. Houve desvio da linha média da mandíbula em relação à linha média da maxila, significativo no grupo fraturado desnutrido, assim como assimetria da maxila e da mandíbula, em especial no final do período experimental. CONCLUSÃO: A fratura do côndilo mandibular em ratos com desnutrição protéica induziu uma assimetria na mandíbula, também com consequências na maxila.

PURPOSE: To investigate the facial symmetry of rats submitted to experimental mandibular condyle fracture and with protein undernutrition (8% of protein) by means of cephalometric measurements. METHODS: Forty-five adult Wistar rats were distributed in three groups: fracture group, submitted to condylar fracture with no changes in diet; undernourished fracture group, submitted to hypoproteic diet and condylar fracture; undernourished group, kept until the end of experiment, without condylar fracture. Displaced fractures of the right condyle were induced under general anesthesia. The specimens were submitted to axial radiographic incidence, and cephalometric mensurations were made using a computer system. The values obtained were subjected to statistical analyses among the groups and between the sides in each group. RESULTS: There was significative decrease of the values of serum proteins and albumin in the undernourished fracture group. There was deviation of the median line of the mandible relative to the median line of the maxilla, significative to undernutrition fracture group, as well as asymmetry of the maxilla and mandible, in special in the final period of experiment. CONCLUSION: The mandibular condyle fracture in rats with proteic undernutrition induced an asymmetry of the mandible, also leading to consequences in the maxilla.

OBJETIVO: A técnica de levantamento de seio maxilar apresenta como possível complicação a perfuração da membrana sinusal. O presente trabalho teve por objetivo comparar duas técnicas que utilizam a cirurgia ultrassônica para realização de enxerto autógeno para levantamento de seio maxilar. MÉTODOS: Dez coelhos foram utilizados no estudo, sendo que um deles não foi submetido a procedimento cirúrgico. Os nove coelhos operados tiveram os seios maxilares preenchidos com enxertos autógenos coletados de díploe externa de calota craniana, nas formas particulado do lado direito e raspado do lado esquerdo, ambos com aparelho ultrassônico. Os dados de densidade óssea nos seios maxilares esquerdo e direito, obtidos por meio de tomografia computadorizada nos sentidos transversal e longitudinal, registrados 90 dias após a realização dos enxertos foram comparados estatisticamente. RESULTADOS: não houve diferenças estatisticamente significantes entre as técnicas de enxerto que utilizaram osso raspado e particulado coletado por meio de dispositivo ultrassônico da calota craniana de coelhos. CONCLUSÃO: A avaliação clínica dos procedimentos nos levou a concluir que o ultrassom piezoelétrico mostrou-se um instrumento clinicamente seguro na abordagem cirúrgica do seio maxilar de coelhos, permitindo a manutenção da integridade da membrana sinusal durante as manobras de ostectomia da parede lateral da maxila e divulsão da membrana sinusal.

PURPOSE: Maxillary sinus lifting is a technique, in which, a possible complication is sinus membrane perforation. The aim of this study was to compare two techniques using ultrasound surgery to perform autogenous graft for maxillary sinus lifting. METHODS: Ten rabbits were used in the study, one of them did not undergo surgery. The other nine rabbits had their maxillary sinuses filled with autogenous bone grafts collected from the external skull diploe in particulate form on the right side, and shaved on the left side, both with ultrasonic device. Data on bone density in left and right maxillary sinus, obtained by computed tomography in transverse and longitudinal sections, recorded 90 days after the grafts, were statistically compared. RESULTS: There were no statistically significant differences between the two techniques that used shaved and particulate bone collected by means of ultrasonic device from rabbit skulls. CONCLUSION: Assessment of operative procedures led to the conclusion that piezoelectric ultrasound was shown to be a safe tool in the surgical approach to the maxillary sinus of rabbits, allowing sinus membrane integrity to be maintained during surgical procedures.

TEMA: ferimentos causados por projéteis de arma de fogo apresentam alta incidência na região da cabeça e face. A articulação temporomandibular pode estar envolvida, além de estruturas anatômicas importantes como o nervo facial, necessitando de equipe multidisciplinar para efetuar tratamento adequado. PROCEDIMENTOS: apresentação de caso clínico de fratura condilar cominutiva causada por projétil de arma de fogo tratado de forma não-cirúrgica associado à terapia miofuncional orofacial. Paciente encaminhado para avaliação e procedimentos fonoaudiológicos após conduta da equipe de cirurgia bucomaxilofacial, sem remoção do projétil, alojado superficialmente, próximo da origem do músculo esternocleidomastóideo à direita, com fratura condilar cominutiva e lesão do nervo facial. Foram aspectos observados em avaliação: mordida aberta anterior, importante redução da amplitude dos movimentos mandibulares com desvios para o lado acometido, ausência de lateralidade contralateral, dor muscular, paralisia e parestesia em terço médio e superior da hemiface direita. Realizadas sessões de terapia miofuncional seguindo protocolo específico para traumas de face constando de: drenagem de edema; manipulações na musculatura levantadora da mandíbula ipsilateral; ampliação e correção dos movimentos mandibulares; procedimentos específicos referentes à paralisia facial e reorganização funcional direcionada. RESULTADOS: após oito semanas de terapia os resultados obtidos mostram restabelecimento de amplitude e da simetria dos movimentos mandibulares, reorganização da mastigação, adequação da deglutição e fala, remissão da sintomatologia dolorosa e remissão da paralisia do terço médio. CONCLUSÃO: o tratamento conservador da fratura por meio da terapia miofuncional orofacial resultou na reabilitação funcional da mandíbula e face dirigindo os movimentos e estimulando a adequação das funções estomatognáticas.

BACKGROUND: firearm wounds are relatively frequent and show high incidence at the head and face area. Temporomandibular joint may be involved, and also some important anatomic structures as the facial nerve directing the need for an interdisciplinary team in order to promote an efficient treatment. PROCEDURES: a case report related to a comminuted condyle fracture caused by firearms with a nonsurgical treatment associated to myofunctional therapy. The patient was referred to Speech and Language Pathologist after the conduct of oral and maxillofacial surgery team, without removing the bullet, lodged superficially near the origin of the sternocleidomastoid muscle on the right side; with comminuted condyle fracture and facial nerve damage. Myofunctional evaluation found an important reduction in the mandibular movement amplitude with severe deviations as for the affected side, no contralateral laterality, muscle pain; paralysis and paresthesia on the right side of the face. Myofunctional therapy followed a specific protocol for facial trauma including: drainage of edemas, specific ipsilateral manipulations on jaw muscles; correction and enlargement of the mandibular movements, specific procedures related to facial paralysis and directed functional reorganization. RESULTS: after eight therapy sessions we obtained: mandibular movements with adequate amplitude and symmetry, chewing reorganization, adequacy of swallowing and speech, remission of painful symptoms and remission of paralysis in the medium third of the face. CONCLUSION: the conservative treatment for comminuted condyle fracture through myofunctional therapy resulted in functional rehabilitation of the jaw and face, directing the movements and stimulating the adequacy of the sthomatognatic functions.

OBJETIVO: Avaliar os efeitos do descolamento e reposicionamento do músculo pterigoideo medial no crescimento da maxila e mandíbula em ratos jovens por meio de cefalometria. MÉTODOS: Foram utilizados 30 ratos Wistar com um mês de idade, distribuídos em três grupos: experimental, controle-operado e controle. No grupo experimental, o descolamento unilateral e reposicionamento do músculo pterigoideo medial foi realizado. O grupo controle-operado foi submetido somente ao acesso cirúrgico e para o grupo controle nenhum procedimento foi realizado. Os animais foram sacrificados aos três meses de idade. Os tecidos moles foram removidos e a mandíbula foi desarticulada. Radiografias axiais do crânio e laterais das hemimandíbulas foram obtidas e a cefalometria foi realizada. Os valores obtidos foram submetidos a análises estatísticas entre os grupos e entre os lados em cada grupo. RESULTADOS: Houve diferenças significantes no comprimento da mandíbula relativo ao processo angular no grupo experimental e na altura do corpo mandibular no grupo controle operado. CONCLUSÃO: O descolamento e reposicionamento experimental do músculo pterigoideo medial durante o período de crescimento em ratos comprometeu o crescimento na região de ângulo, resultando em assimetria da mandíbula.

PURPOSE: To analyze the effects of detachment and repositioning of the medial pterygoid muscle on the growth of the maxilla and mandible of young rats through cephalometry. METHODS: Thirty one-month-old Wistar rats were used, distributed into three groups: experimental, sham-operated and control. In the experimental group, unilateral detachment and repositioning of the medial pterygoid muscle was performed. The sham-operated group only underwent surgical access, and the control group did not undergo any procedure. The animals were sacrificed at the age of three months. Their soft tissues were removed and the mandible was disarticulated. Radiographs of the skull in axial projection and the hemimandibles in lateral projection were obtained, and cephalometry was performed. The values obtained were subjected to statistical analyses among the groups and between the sides in each group. RESULTS: There were significant differences in the length of the mandible relative to the angular process in the experimental group and in the height of the mandibular body in the sham-operated group. CONCLUSION: The experimental detachment and repositioning of the medial pterygoid muscle during the growth period in rats affected the growth of the angle region, resulting in asymmetry of the mandible.

This study analyzed the effects of the unilateral removal and dissection of the masseter muscle on the facial growth of young rats. A total of 30 one-month-old Wistar rats were used. Unilateral complete removal of the masseter muscle was performed in the removal group, and detachment followed by repositioning of the masseter muscle was performed in the dissection group, while only surgical access was performed in the sham-operated group. The animals were sacrificed at three months of age. Axial radiographic projections of the skulls and lateral projections of the hemimandibles were taken. Cephalometric evaluations were made and the values obtained were submitted to statistical analyses. In the removal group, there were contour alterations of the angular process, and a significant homolateral difference in the length of the maxilla and a significant bilateral difference in the height of the mandibular body and the length of the mandible were observed. Comparison among groups revealed significance only in the removal group. It was concluded that the experimental removal of the masseter muscle during the growing period in rats induced atrophic changes in the angular process, as well as asymmetry of the maxilla and shortening of the whole mandible.

OBJETIVO: avaliação clínica dos procedimentos de expansão cirurgicamente assistida da maxila. METODOLOGIA: foram avaliados 10 pacientes tratados através da expansão ortopédica com auxílio cirúrgico, conhecida como expansão cirurgicamente assistida da maxila (ECAM). Avaliou-se a efetividade deste procedimento cirúrgico no auxílio à expansão transversal da maxila proporcionada através de aparelho do tipo Hyrax, a estabilidade desta expansão, as ocorrências pós-operatórias, a quantidade e qualidade da expansão conseguida e alterações estéticas deste procedimento. RESULTADOS E CONCLUSÕES: concluiu-se, com um acompanhamento a longo prazo, que a ECAM trata-se de um procedimento eficiente, estável, que proporciona mudanças funcionais e pouca alteração estética facial.

AIM: clinical evaluation of surgically assisted maxillary expansion. METHODS: the present study evaluated 10 patients who underwent surgically assisted maxillary expansion. The efficacy of the surgical procedure helping transverse maxillary expansion given by the Hyrax, expansion stability, post-operatory discomfort during the activation of the device, the quantity and quality of the expansion achieved, the age of the patients, nasal base alteration, and nasal breathing were analyzed. RESULTS AND CONCLUSIONS: from the results, it was possible to observe that surgically assisted maxillary expansion is an efficient and stable treatment, which offers functional changes and minimal aesthetic alterations.

O objetivo deste trabalho foi avaliar os efeitos da injeção de dois agentes flogísticos, ou seja, carragenina ou formalina, na ATM do rato, e a evolução do quadro inflamatório provocado por essas substâncias. Foram utilizados 45 ratos, divididos em dois grupos experimentais e um grupo controle. Os animais foram sacrificados em lotes de três de cada grupo após três horas, 24 horas, três dias, sete dias e 15 dias da injeção. Histologicamente a reação inflamatória em ambos os grupos experimentais iniciou-se com infiltrado inflamatório agudo, tornando-se misto e depois crônico. Sinais de hiperplasia da membrana sinovial foram observados aos três dias, intensos aos sete dias, estando presentes aos 15 dias somente no grupo da formalina. A injeção de solução salina (grupo controle) não provocou reação inflamatória. No presente trabalho foi concluído que uma injeção local única na região da ATM de carragenina ou de formalina foi suficiente para induzir reação inflamatória na articulação e nos tecidos moles periarticulares. As reações inflamatórias resultantes da injeção desses agentes flogísticos foram semelhantes, mas o grupo da formalina mostrou infiltrado inflamatório mais persistente.

The aim of this study was to evaluate the effects of the injection of two phlogistic agents, carrageenan and formalin, in the rat TMJ, and the inflammatory process induced by these substances. In this study, a total of 45 adult rats were distributed in two experimental groups and a control group. The animals were sacrificed after three hours, 24 hours, three days, seven days, and 15 days after a single injection of each substance. Histological data initially demonstrated an inflammatory process represented by acute infiltration, which later became mixed, and finally chronic in both experimental groups. Hyperplasia of the synovial membrane was observed after three days, being intense at seven days, and present after 15 days only in the formalin group. Local saline injection in the control group caused no inflammatory reaction. It was concluded that a single local injection of carrageenan or formalin was enough to induce inflammatory reaction in the TMJ and periarticular soft tissues, and that the resulting processes were similar, but more persistent in the formalin group.

OBJETIVO: Analisar as conseqüências no crescimento de maxila e mandíbula de defeito ósseo cirúrgico simulando fratura no ramo da mandíbula. MÉTODOS: Foram utilizados 25 ratos Wistar com um mês de idade. Sob anestesia geral e por meio de incisão submandibular. Foi realizada osteotomia vertical no ramo da mandíbula do lado direito com emprego de motor cirúrgico. Após período de dois meses os animais foram sacrificados, os tecidos moles retirados e as hemimandíbulas desarticuladas. Foram realizadas incidências radiográficas axiais para o crânio e laterais para as hemimandíbulas. A seguir, por intermédio de um sistema de computador foram obtidas medidas lineares da maxila e das hemimandíbulas. Foi empregado o teste "t" de Student para verificação da significância da diferença entre os lados experimental e controle. RESULTADOS: A diferença foi significante para a altura do ramo (p=0,010) e comprimento da mandíbula referente ao côndilo (p=0,015) e ao ângulo (p<0,001), não havendo diferença significante para as mensurações da maxila. CONCLUSÃO: As conseqüências do defeito ósseo cirúrgico experimental no ramo da mandíbula na fase de crescimento foram a diminuição da altura do ramo e do comprimento da mandíbula.

PURPOSE: To analyse the consequences on the growth of maxilla and mandible of a surgical bone defect that simulates a mandibular ramus fracture. METHODS: A group of 25 one-month-old Wistar rats were used in this study. Under general anesthesia, and through a submandibular incision, a vertical osteotomy on the right side of the mandibular ramus was made using a surgical drill. The animals were sacrificed after two months, soft tissues removed, and the mandible disarticulated. The skull was submitted to axial radiograph and the hemimandibles to a lateral radiograph. With these, cephalometric mensurations were made through a computer system, and the obtained values submitted to Student's t-test. RESULTS: The height of the mandibular ramus presented significant difference (p=0,010) as well as the length of mandible, both to the condyle (P=0,015) and the angle (p=0,001). There was no significant difference to the mensurations of the maxilla. CONCLUSION: The consequences of the experimental surgical bone defect on the mandibular ramus in the growing period were the lessening of the mandibular height and length.