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1.
BMC Oral Health ; 24(1): 88, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38229117

RESUMO

OBJECTIVE: The aim of this study was to present an innovative surgical protocol, navigation-based endoscopic enucleation (NBEE) for the treatment of large mandibular cystic lesions involving the mandibular ramus. METHODS: Twelve patients who presented with a large mandibular cystic lesion involving the mandibular ramus were enrolled in this study. Preoperative planning and intraoperative navigation were performed in all 12 patients. RESULTS: All patients in this study were treated with navigation-based endoscopic enucleation successfully. The follow-up period ranged from 7 to 10 months. Bone regenerated was found in all patients postoperatively. Three patients experienced temporary mandibular nerve palsy, and all relieved within 2 months. No pathological bone fracture was found during surgery. CONCLUSIONS: The use of navigation-based endoscopic enucleation (NBEE) for the treatment of large mandibular cystic lesions involving the ramus proved to be an effective method for complete and precise enucleation of the cystic lesion that also preserved the surrounding tissue.


Assuntos
Endoscopia , Mandíbula , Humanos , Mandíbula/cirurgia , Endoscopia/métodos , Osteotomia/métodos
2.
Surg Radiol Anat ; 44(4): 551-558, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35303119

RESUMO

OBJECTIVES: The purpose of this study was to investigate short- and long-term postoperative changes of both morphology and transverse stability in mandibular ramus after intraoral vertical ramus osteotomy (IVRO) in patients with jaw deformity using three-dimensional (3D) orthognathic surgery planning treatment software for measurement of distances and angles. STUDY DESIGN: This retrospective study included consecutive patients with skeletal Class III malocclusion who had undergone intraoral vertical ramus osteotomy and computed tomography images before (T0), immediately after (T1), and 1 year after (T2) surgery. Reference points, reference lines and evaluation items were designated on the reconstructed 3D surface models to measure distances, angles and volume. The average values at T0, T1, T2 and time-dependent changes in variables were obtained. RESULTS: After surgery, the condylar length, ramal height, mandibular body length and mandibular ramus volume were significantly decreased (P < 0.01), while clinically insignificant change was observed from T1 to T2. The angular length was increased immediately after surgery (P < 0.05), but it was decreased 1 year after surgery (P < 0.05). Lateral ramal inclination showed significant increase after surgery (P < 0.05) and maintained at T2. CONCLUSION: Changes in the morphology of the mandibular ramus caused by IVRO do not obviously bring negative effect on facial appearance. Furthermore, despite position and angle of mandibular ramus changed after IVRO, good transverse stability was observed postoperatively. Therefore, IVRO technique can be safely used without compromising esthetic results.


Assuntos
Osteotomia Sagital do Ramo Mandibular , Prognatismo , Cefalometria/métodos , Humanos , Mandíbula/diagnóstico por imagem , Mandíbula/cirurgia , Osteotomia Sagital do Ramo Mandibular/métodos , Prognatismo/cirurgia , Estudos Retrospectivos
3.
Clin Oral Implants Res ; 31(4): 328-340, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31898345

RESUMO

OBJECTIVES: To report the clinical and radiographic outcomes of patients presenting with edentulous and atrophic ridges and treated with autogenous mandibular bone blocks and rehabilitated with implant-supported prostheses. MATERIALS AND METHODS: From 1997 to 2015, 75 patients presenting with bone defects of the jaws were grafted with autogenous mandibular bone blocks. One-hundred eighty-two implants were placed 4 to 12 months later and loaded 3 to 10 months later: the mean follow-up was 10 years (range: 3-16 years). The following outcomes were recorded: (a) complication rate of the reconstructive procedure; (b) bone graft resorption before implant placement; (c) peri-implant bone resorption; (d) implant-related complications; and (e) implant survival and success rates. RESULTS: Postoperative recovery was uneventful in the majority of patients. An early dehiscence occurred in three patients, but with no significant bone loss, while 3 experienced temporary paraesthesia. The mean vertical and horizontal bone resorption before implant placement was 0.18 mm (standard deviation [SD] = 0.43) and 0.15 mm (SD = 0.42), respectively. The mean peri-implant bone loss ± standard deviation was 1.06 ± 1.19 (range: 0.00-5.05) at patient level and 1.11 ± 1.26 (range: 0.00-5.20) at implant level. Two implants in 2 patients lost integration and were removed; 10 implants in 7 patients developed peri-implantitis, but healed after surgical treatment. The cumulative implant survival and success rates were 98.11% and 85.16%, respectively. CONCLUSION: Implants placed in areas reconstructed with mandibular bone blocks presented survival rates consistent with those obtained for implants placed in native bone.


Assuntos
Aumento do Rebordo Alveolar , Implantes Dentários , Animais , Transplante Ósseo , Bovinos , Colágeno , Implantação Dentária Endóssea , Prótese Dentária Fixada por Implante , Falha de Restauração Dentária , Seguimentos , Humanos , Minerais , Estudos Retrospectivos , Resultado do Tratamento
4.
Surg Radiol Anat ; 41(6): 663-667, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30903207

RESUMO

OBJECTIVE: The purpose of this article was to assess the anatomical relationship between the lingula and the antilingula by measuring the projection of lingula on the lateral side of the ramus on CBCT. METHODS: This study collected CBCT images of 204 mandibular halves in 102 Chinese patients without any damage. We projected the lingula to the lateral side of the mandibular ramus and examined the distance and position relationship between the projection point and the antilingula using three-dimensional computed tomography (3DCT) created by image software. RESULTS: In 204 sides the antilingula appeared in 92 cases, 52 on right and 40 on left. The antilingula was used as a fixed point, in four cases the lingula projection in the anterior superior part, 38 cases in the posterior superior part, 45 cases in the posterior inferior part and zero case in the anterior inferior part. Scatter plots diagrammatic representation in four quadrants centered on the antilingula showed that 79% cases (73/92) lied in a 90° fan shape ranged in 5-10 mm radius in the posterior superior and inferior quadrant. CONCLUSION: The lingula mainly located in the posterior superior and inferior part from the antilingula in a 90° fan shape ranged in 5-10 mm radius. The osteotomy incision should be avoided in this area.


Assuntos
Mandíbula/anatomia & histologia , Nervo Mandibular/anatomia & histologia , Povo Asiático , Tomografia Computadorizada de Feixe Cônico , Humanos , Imageamento Tridimensional , Mandíbula/diagnóstico por imagem , Mandíbula/cirurgia , Traumatismos do Nervo Mandibular/etiologia , Traumatismos do Nervo Mandibular/prevenção & controle , Osteotomia Sagital do Ramo Mandibular/efeitos adversos , Osteotomia Sagital do Ramo Mandibular/métodos
5.
Surg Radiol Anat ; 41(9): 1071-1074, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30701271

RESUMO

Anatomical variations of the mandibular canal as well as the presence of accessory canals and foramina are common findings in the human mandible. Here, we present a previously unreported type of anatomical variation, consisting of a large full-thickness bone defect of the right mandibular ramus, observed in a young male unearthed from a mediaeval cemetery located in North-Eastern Italy. The defect was located very close to, yet not directly connected with, the mandibular canal. Awareness of the existence of deviations from the anatomical norm such as that we describe here is strategic to avoid diagnostic misinterpretations, minimise technical hitches, and prevent clinical complications during invasive procedures in the region of the mandible.


Assuntos
Variação Anatômica , Restos Mortais/anormalidades , Mandíbula/anormalidades , Tomografia Computadorizada de Feixe Cônico , História Medieval , Humanos , Itália , Masculino , Paleopatologia , Adulto Jovem
6.
Surg Radiol Anat ; 41(4): 455-460, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30701272

RESUMO

PURPOSE: The purpose of this study was to investigate the Gonial angle in relation to the position of the lingula using computerized image analysis to guide the oral surgeons to prevent injury to the inferior alveolar nerve and peripheral blood vessels during surgery. METHODS: We measured Gonial angle sizes of bilateral rami and the distances from the lingula tip to the mandibular notch (LN), the anterior (LA) and posterior (LP) margin of the mandibular ramus, the mandibular base (LB) and the occlusive plane (h) in 407 Chinese adults with CBCT. RESULTS: In males, the mean distance of LN was 17.64 mm in the low Gonial angle group while 16.76 mm in the high Gonial angle group, which was significantly different between two groups (P < 0.001). The distance of LA in LGA group was obviously longer than that in HGA group (P < 0.001). The mean distance LP of men was 17.94 mm in LGA group while 16.9 mm in HGA group (P < 0.001). In females, the mean distance of LB in LGA group was 33.32 mm and 32.37 mm in HGA group (P < 0.01). CONCLUSION: We discovered that the segment of the mandibular branch, between the mandibular lingula and the mandibular angle, was obviously smaller in the HGA group than that in the LGA group.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Mandíbula/anatomia & histologia , Mandíbula/diagnóstico por imagem , Nervo Mandibular/anatomia & histologia , Nervo Mandibular/diagnóstico por imagem , Adulto , Pontos de Referência Anatômicos , Feminino , Humanos , Masculino , Fatores Sexuais
7.
Stomatologiia (Mosk) ; 98(3): 94-96, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31322603

RESUMO

The study samples included 12 anatomical specimens taken from the fixed corpses of various gender and age. Pterygomandibular space topography was assessed by macro - and micropreparation methods. The landmarks for the universal way of mandibular anesthesia were defined associated with low risk of medial pterygoid muscle, lingual nerve, inferior alveolar neurovascular bundle damage. The study results allow increasing the efficiency and safety of anesthesia of the lower jaw teeth.


Assuntos
Anestesia Dentária , Nervo Mandibular , Humanos , Nervo Lingual , Mandíbula , Nervo Mandibular/anatomia & histologia , Músculos Pterigoides
8.
Folia Morphol (Warsz) ; 77(4): 711-716, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29569700

RESUMO

BACKGROUND: Medial depression of the mandibular ramus (MDMR) is an anatomical depression with unknown aetiology and described as a result of a slender mandibular ramus in the area of the mandibular notch. It is suggested that MDMR may be due to variations in muscle functions. The aim of this study is to compare the bite force of patients with and without MDMR detected on panoramic radiographs. MATERIALS AND METHODS: One hundred and ten patients (55 women and 55 men; mean age 22.69 ± 2.85 years) participated in this study. Patients were divided into two groups based on the presence of MDMR. Bite force of 55 patients with MRMD and 55 patients without MDMR were determined using a bite force sensor. Non-parametric tests were used to assess differences between groups. RESULTS: Measurements showed statistically significant differences in bite force between genders (p = 0.00) with men having higher values (535.98 ± 187.85 N) than women (363.59 ± 139.56 N). The mean bite force in the sides with and without MDMR was 538.19 ± 196.94 N and 396.22 ± 157.69 N, respectively. There was a statistically significant difference between groups with and without MDMR (p = 0.00). There was no statistically significant difference in bite force between groups according to Angle's classification (p = 0.581). CONCLUSIONS: This study suggests that the presence of MDMR may be an indicator of high muscle activity. Patients with MDMR should be carefully examined for the risk of relapse prior to any surgical intervention.


Assuntos
Força de Mordida , Mandíbula/anatomia & histologia , Mandíbula/fisiologia , Feminino , Humanos , Masculino , Mandíbula/diagnóstico por imagem , Adulto Jovem
9.
Folia Morphol (Warsz) ; 76(1): 82-86, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27665949

RESUMO

BACKGROUND: The identification of an individual from skeletal remains plays a vital role in forensic investigation as it is essential for the identification of the individual's age, sex, and/or race and further analysis. Skeletal characteristics differ from one population group to another since population-specific osteometric standards exist for sex determination. Since the mandible is the largest, strongest and most durable compact facial bone, it is the best preserved after death. While sexual dimorphism of the mandible is indicated by its shape and size, morphometric analysis is more accurate in the determination of sex from the skull. The aim of this study was to evaluate the morphometric parameters of the mandible in the Durban Metropolitan population. MATERIALS AND METHODS: Various morphometric parameters of the mandible were measured and assessed in 265 digital panoramic radiographs aged between 16 and 30 years (n = 530). Each parameter recorded was statistically analysed using SPSS to determine if a relationship existed between the parameter, and sex and age. RESULTS: In this study the morphometric parameters of the male mandibles were greater than that of the females. This concurred with the findings of previous studies. The length of the mandibular ramus on the right and left sides was statistically significant with sex. CONCLUSIONS: This correlated with previous studies, indicating that the length of the mandibular ramus generally has higher sexual dimorphism than any other morphometric mandibular parameter (p = 0.000). However, only the length of the right mandibular body was statistically significant when compared with sex (p = 0.040). The findings of this study may assist forensic investigators, anatomists, anthropologists and maxillo-facial surgeons.


Assuntos
Mandíbula/diagnóstico por imagem , Caracteres Sexuais , Adolescente , Adulto , Feminino , Humanos , Masculino , Radiografia , África do Sul
10.
Cranio ; 34(1): 58-63, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25371100

RESUMO

OBJECTIVES: To consider the biologic behaviors of keratocystic odontogenic tumors (KCOTs) and ameloblastomas and dentigerous cysts. METHODS: A 63-year-old Japanese man presented with swelling and discomfort in the left cheek during jaw movement. Examination revealed a multilocular lesion within the mandible extending from the left second premolar to the left mandibular ramus and coronoid process; the lesion contained a deviated impacted tooth. The tumor had expanded beyond the bone and was invading the masseter and medial pterygoid muscles. Marginal mandibulectomy with a free iliac bone graft was performed. RESULTS: No recurrence was observed during a 7-year follow-up. DISCUSSION: The histopathological diagnosis of the lesion showed it was a KCOT. These tumors usually grow within the bone, causing bone expansion. However, this tumor had expanded beyond the bone and invaded surrounding muscles. Thus, KCOTs can, in rare cases, manifest themselves as described here. Evaluating preoperative images and histopathological findings is important to determine the optimal treatment strategy.


Assuntos
Mandíbula/patologia , Neoplasias Mandibulares/patologia , Cistos Odontogênicos/patologia , Tumores Odontogênicos/patologia , Dente Impactado/patologia , Tecido Adiposo/diagnóstico por imagem , Tecido Adiposo/patologia , Ameloblastoma/patologia , Povo Asiático , Dente Pré-Molar/patologia , Transplante Ósseo , Bochecha , Cisto Dentígero/patologia , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Mandíbula/diagnóstico por imagem , Mandíbula/cirurgia , Neoplasias Mandibulares/diagnóstico por imagem , Neoplasias Mandibulares/cirurgia , Osteotomia Mandibular/métodos , Músculo Masseter/patologia , Pessoa de Meia-Idade , Cistos Odontogênicos/complicações , Cistos Odontogênicos/diagnóstico por imagem , Cistos Odontogênicos/cirurgia , Tumores Odontogênicos/complicações , Tumores Odontogênicos/diagnóstico por imagem , Tumores Odontogênicos/cirurgia , Músculos Pterigoides/patologia , Tomografia Computadorizada por Raios X
11.
J Prosthodont ; 25(8): 670-674, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27272018

RESUMO

PURPOSE: Curvature of the posterior border of the mandibular ramus at the occlusal plane has been described as a morphological trait for males. Controversy over the accuracy of this method remains among researchers; studies employing similar methods report accuracy rates for successful gender identification ranging from 59% to 99%. This blind study assessed evaluators' ability to determine gender based on the presence or absence of curvature of the posterior margin of the mandibular ramus through panoramic radiographs. MATERIALS AND METHODS: Randomly selected panoramic radiographs were obtained from The Ohio State University College of Dentistry for 413 adult male (M) and female (F) subjects. Two evaluators separately assigned ratings using a similar method to the Loth and Henenberg methodology to each subject on the right and left sides of mandibular rami. The ratings were based upon three criteria: (1) presence of curvature at the occlusal plane (M), (2) presence of curvature but not at the occlusal plane (F), and (3) lack of curvature (F). Pearson exact chi-squared test was used to evaluate the statistical strength of the ratings. RESULTS: The evaluators were only in agreement for both the right and left rami in roughly two-thirds (66.8%) of cases when there was no excessive tooth loss (ETL); however, the inter-observer agreement improved to 82.1% for those rami associated with ETL. Inter-observer agreement occurred in 72.9% of female rami and in only 64.4% of male rami. CONCLUSION: The results of this study indicated that assessment of posterior border curvature of  mandibular rami through panoramic radiographs was not a reliable indicator of gender and was further plagued by unacceptably high levels of inter-observer disagreement.


Assuntos
Oclusão Dentária , Mandíbula/anatomia & histologia , Análise para Determinação do Sexo , Feminino , Humanos , Masculino , Mandíbula/diagnóstico por imagem , Radiografia Panorâmica
12.
J Oral Implantol ; 41 Spec No: 366-71, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24702157

RESUMO

The aim of the present study was to use cone-beam computerized tomography (CBCT) to assess horizontal bone augmentation using block grafts, harvested from either the iliac crest (IC) or mandibular ramus (MR) combined with particulate xenograft and a collagen membrane for in the severe maxillary anterior ridge defects (cases Class III-IV according to Cadwood and Howell's classification). Fourteen healthy partially edentulous patients requiring extensive horizontal bone reconstruction in the anterior maxilla were selected for the study. Nineteen onlay block grafts (from IC or MR) were placed. The amount of horizontal bone gain was recorded by CBCT at 3 levels (5, 7, and 11 mm from the residual ridge) and at the time of bone grafting as well as the time of implant placement (≈5 months). Both block donor sites provided enough ridge width for proper implant placement. Nonetheless, IC had significantly greater ridge width gain than MR (Student t test) (4.93 mm vs 3.23 mm). This was further confirmed by nonparametric Mann-Whitney test (P = .007). Moreover, mean pristine ridge and grafted ridge values showed a direct association (Spearman coefficient of correlation = .336). A combination of block graft, obtained from the IC or MR, combined with particulate xenograft then covered with an absorbable collagen membrane is a predictable technique for augmenting anterior maxillary horizontal ridge deficiency.


Assuntos
Aumento do Rebordo Alveolar/métodos , Autoenxertos/transplante , Transplante Ósseo/métodos , Tomografia Computadorizada de Feixe Cônico/métodos , Xenoenxertos/transplante , Maxila/cirurgia , Implantes Absorvíveis , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Atrofia , Autoenxertos/diagnóstico por imagem , Substitutos Ósseos/uso terapêutico , Colágeno , Xenoenxertos/diagnóstico por imagem , Humanos , Ílio/cirurgia , Mandíbula/cirurgia , Maxila/diagnóstico por imagem , Maxila/patologia , Membranas Artificiais , Pessoa de Meia-Idade , Minerais/uso terapêutico , Procedimentos de Cirurgia Plástica/métodos , Coleta de Tecidos e Órgãos/métodos , Sítio Doador de Transplante/cirurgia , Adulto Jovem
13.
Ann Anat ; 253: 152229, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38367950

RESUMO

BACKGROUND: The study examines a sample of patients presenting for viscerocranial computer tomography that does not display any apparent signs of asymmetry, assesses the three-dimensional congruency of the mandibular ramus, and focuses on differences in age and gender. METHODS: This cross-sectional cohort study screened viscerocranial CT data of patients without deformation or developmental anomalies. Segmentations were obtained from the left and right sides and superimposed according to the best-fit alignment. Comparisons were made to evaluate three-dimensional congruency and compared between subgroups according to age and gender. RESULTS: Two hundred and sixty-eight patients were screened, and one hundred patients met the inclusion criteria. There were no statistical differences between the left and right sides of the mandibular ramus. Also, there were no differences between the subgroups. The overall root mean square was 0.75 ± 0.15 mm, and the mean absolute distance from the mean was 0.54 ± 0.10 mm. CONCLUSION: The mean difference was less than one millimetre, far below the two-millimetre distance described in the literature that defines relative symmetry. Our study population displays a high degree of three-dimensional congruency. Our findings help to understand that there is sufficient three-dimensional congruency of the mandibular ramus, thus contributing to facilitating CAD-CAM-based procedures based on symmetry for this specific anatomic structure.


Assuntos
Imageamento Tridimensional , Mandíbula , Humanos , Estudos Transversais , Imageamento Tridimensional/métodos , Mandíbula/diagnóstico por imagem , Mandíbula/anormalidades , Face , Cefalometria/métodos
14.
Rev Cient Odontol (Lima) ; 12(2): e194, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39119124

RESUMO

Objective: This study aims to identify fracture patterns on the lingual aspect of the mandible following Bilateral Sagittal Osteotomy of the Mandibular Ramus and correlate these patterns with mandibular anatomical characteristics in patients with cleft lip and palate. Methods: Two hundred cone beam CT scans were analyzed, with 100 scans in the preoperative period to assess mandibular anatomy and 100 in the postoperative period to evaluate the course of fractures on the lingual surface after surgery. Results: Statistical analysis revealed no correlation between the depth of the mandibular fossa and the type of fracture after bilateral sagittal osteotomy. Similarly, there was no association between the height and angle of the mandibular body and the type of fracture. The most common fracture type observed was the type 3 pattern, characterized by a line running through the mandibular canal. Furthermore, no relationship was identified between the studied anatomical aspects and the occurrence of undesired fractures. Conclusions: The anatomical data presented in this study can assist surgeons in selecting the safest surgical techniques and optimal osteotomy sites, particularly in patients with cleft lip and palate.


Objetivo: Este estudio tiene como objetivo identificar los patrones de fractura en la superfície lingual de la mandíbula después de la osteotomía sagital bilateral de la rama mandibular y correlacionar estos patrones con las características anatómicas mandibulares en pacientes com fisura labiopalatina. Métodos: Se analizaron doscientas tomografías computarizadas de haz cónico, con cien tomografías en el período preoperatorio para evaluar la anatomía mandibular y cien en el período postoperatorio para evaluar el curso de las fracturas en la superficie lingual después de la cirugía. Resultados: El análisis estadístico no reveló correlación entre la profundidad de la fosa mandibular y el tipo de fractura después de la osteotomía sagital bilateral. Del mismo modo, no hubo asociación entre la altura y el ángulo del cuerpo mandibular y el tipo de fractura. El tipo de fractura más común observado fue el patrón tipo 3, caracterizado por una línea que atraviesa el canal mandibular. Además, no se identificó relación entre los aspectos anatómicos estudiados y la ocurrencia de fracturas no deseadas. Conclusiones: Los datos anatómicos presentados en este estudio pueden ayudar a los cirujanos a seleccionar las técnicas quirúrgicas más seguras y los sitios de osteotomía óptimos, especialmente en pacientes con fisura labiopalatina.

15.
Cureus ; 16(8): e67715, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39318915

RESUMO

OBJECTIVES: To investigate the ethnic variations concerning the lingula and ramus of the mandible, with particular emphasis on sagittal split ramus osteotomy (SSRO) in orthognathic surgery. MATERIALS AND METHODS: This study examined Cone beam computed tomography (CBCT) scans from the Kenyan and Malay populations. Lingula morphology was classified into four categories. Morphometric measurements included lingula size, height above the occlusal plane, distance to the second mandibular molar, and distance from its apex to all four mandible borders. Regarding the ramus of the mandible, the thickness of each cortical plate, trabecular bone, and overall thickness were determined at two points. Furthermore, points of fusion of cortical plates were determined in both the vertical and horizontal planes. RESULTS: Among Kenyans, the triangular shape was most common (46.5%, n = 80 sides), while truncated was most common among Malays (34.4%, n = 57 sides). The overall mean size of lingula differed significantly between Kenyan (7.37 ± 2.19 mm) and Malay (4.14 ± 2.50 mm) populations (p<0.001). The lingula was more located postero-superiorly in Kenyans compared to Malays (p < 0.001). The mean distance from the distal aspect of the second mandibular molar to the lingula was 38.37 ± 4.98 mm among Kenyans, in contrast to 31.95 ± 0.03 mm among Malays (p < 0.001). The Malays exhibited a thicker mandible with a larger trabecular distance (5.99 ± 1.41 mm and 3.41 ± 1.29 mm, respectively) than Kenyans (5.28 ± 1.39 mm and 1.98 ± 0.98 mm, respectively) (p < 0.001). The points of fusion of the cortical plates differed significantly between Kenyans and Malays. CONCLUSION: This study focuses on two ethnic groups, Kenyans and Malays, and brings to light the ethnic-based differences in the position of the lingula and the dimensions of the mandibular ramus, both of which are essential considerations in orthognathic surgery. Preoperative consideration of such variations is warranted, potentially mitigating iatrogenic injuries and enhancing successful patient outcomes.

16.
Quant Imaging Med Surg ; 14(2): 1652-1659, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38415165

RESUMO

Background: Sagittal split ramus osteotomy is an established procedure used in oral and maxillofacial surgery. Major bleeding is representative intraoperative complication involves vessels such as the inferior alveolar, facial, and maxillary arteries and accompanying veins, in particular the retromandibular vein (RMV). We previously described the RMV course patterns using embalmed cadavers. However, owing to the possible influence of formalin fixation and unclear skeletal classification of the jaws, the present study aimed to use contrast-enhanced computed tomography to confirm the RMV in patients with defined jaw deformities. Methods: Twenty patients with orthognathic jaw deformities (40 sides) were included. The RMV and the lateral and posterior views of the mandible were evaluated using contrast-enhanced computed tomography. Course patterns and RMV positions were classified as previously reported. Results: Three patterns were identified in the lateral view. Type A: RMV posterior to the posterior border of the ramus (n=25; 62.5%). Type B: adjoining the posterior border of the ramus (n=12; 30.0%). Type C: anterior to the posterior border of the ramus (n=3; 7.5%). Five course patterns were identified in the posterior view. Pattern I: rectilinear course running medial to the posterior border of the ramus (n=3; 7.5%). Pattern II: diagonal course running medially from immediately posterior to posterior border of the ramus (n=11; 27.5%). Pattern III: rectilinear course running immediately posterior to the posterior border of the ramus (n=12; 30.0%). Pattern IV: diagonal course running from lateral to medial relative to the posterior border of the ramus (n=8; 20.0%). Pattern V: diagonal course running from lateral to immediately posterior relative to the posterior border of the ramus (n=6; 15.0%). In the no-course pattern group, the RMV inferior to the lingula was lateral to its position and superior to that of the lingula. In half of the cases, the left and right sides exhibited different running patterns. We observed no correlation between the skeletal patterns of jaw deformities and the course of the RMV. Conclusions: Type B/Pattern II that runs in a straight line bordering the posterior margin of the ramus requires the most attention during surgery. These findings suggest the possibility of predicting intraoperative bleeding risk.

17.
Korean J Orthod ; 53(3): 185-193, 2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-37113038

RESUMO

Objective: The growth and development of the mandible strongly depend on modeling changes occurring at its ramus. Here, we investigated covariance patterns between the morphology of the ramus and the rest of the face. Methods: Lateral cephalograms of 159 adults (55 males and 104 females) with no history of orthodontic treatment were collected. Geometric morphometrics with sliding semi-landmarks was used. The covariance between the ramus and face was investigated using a two-block partial least squares analysis (PLS). Sexual dimorphism and allometry were also assessed. Results: Differences in the divergence of the face and anteroposterior relationship of the jaws accounted for 24.1% and 21.6% of shape variation in the sample, respectively. Shape variation was greater in the sagittal plane for males than for females (30.7% vs. 17.4%), whereas variation in the vertical plane was similar for both sexes (23.7% for males and 25.4% for females). Size-related allometric differences between the sexes accounted for the shape variation to a maximum of 6% regarding the face. Regarding the covariation between the shapes of the ramus and the rest of the face, wider and shorter rami were associated with a decreased lower anterior facial height as well as a prognathic mandible and maxilla (PLS 1, 45.5% of the covariance). Additionally, a more posteriorly inclined ramus in the lower region was correlated with a Class II pattern and flat mandibular plane. Conclusions: The width, height, and inclination of the ramus were correlated with facial shape changes in the vertical and sagittal planes.

18.
Front Pediatr ; 11: 1157607, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37138574

RESUMO

Introduction: This study aims to quantitively analyze mandibular ramus and body deformities, assessing the asymmetry and progression in different components. Methods: This is a retrospective study on hemifacial microsomia children. They were divided into mild/severe groups by Pruzansky-Kaban classification and into three age groups (<1 year,1-5 years, 6-12 years old). Linear and volumetric measurements of the ramus and the body were collected via their preoperative imaging data to compare between the different sides and severities, using independent and paired tests, respectively. The progression of asymmetry was assessed by changes in affected/contralateral ratios with age using multi-group comparisons. Results: Two hundred and ten unilateral cases were studied. Generally, the affected ramus and body were significantly smaller than those on the contralateral side. Linear measurements on the affected side were shorter in the severe group. Regarding affected/contralateral ratios, the body was less affected than the ramus. Progressively decreased affected/contralateral ratios of body length, dentate segment volume, and hemimandible volume were found. Discussion: There were asymmetries in mandibular ramus and body regions, which involved the ramus more. A significant contribution to progressive asymmetry from the body suggests treatment focus in this region.

19.
J Oral Maxillofac Pathol ; 27(1): 66-70, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37234315

RESUMO

Background: In medico-legal investigations identification of skeletal remains is of utmost importance. The skeletal remains most commonly investigated are pelvic and skull bones with the mandible an important element to analyze sexual dimorphism. Mandibular ramus can differentiate between the two genders as the stages of mandibular development, growth rates, and duration are different in both genders. Metric analysis on the radiographs is found to be of higher values when skeletal sex determination is considered. Aims and Objectives: 1) To compare and evaluate the various measurements of the mandibular ramus on digital OPG's. 2) To assess the usefulness of mandibular ramus as an aid in gender determination in the Bagalkot population. Materials and Methods: A retrospective study was conducted on 80 patients (40 males & 40 females) using Kodak 8000 C digital panoramic radiographs of the Bagalkot population with ages ranging from 18 to 58 years. Five parameters namely coronoid ramus height, condyle ramus height, condyle coronoid breadth, maximum ramus breadth, and minimum ramus breadth were taken into consideration, the values were measured and data were analyzed. Statistical analysis was done using SPSS software. Results: In the present study, all the measurements of the mandibular ramus on digital panoramic radiographs showed a statistically significant difference between both the genders except for minimum ramus breadth which was found to be insignificant. Conclusion: Discriminant analysis of mandibular ramus using panoramic radiography can be used as an effective tool in gender determination and can be used as an aid in forensic sciences.

20.
J Dent (Shiraz) ; 24(1): 1-6, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36864988

RESUMO

Statement of the Problem: Medial depression of the mandibular ramus (MDMR) as a normal anatomical variation might complicate orthognatic surgeries that involve ramus. When planning an orthognatic surgery, it is clinically valuable to notice MDMR in osteotomy site to decrease the risk of failure. Purpose: The aim of present study was to evaluate the prevalence as well as characteristics of MDMR in three skeletal sagittal classifications. Materials and Method: This cross sectional study evaluated 530 cone beam computed tomography (CBCT) scans, of which 220 were enrolled. The skeletal sagittal classification, the presence of MDMR, the shape, depth, and width of MDMR were recorded for each patient by two examiners. Chi-square test was performed to determine the differences between three skeletal sagittal groups and between two genders. Results: The overall prevalence of MDMR was 60.45%. MDMR was mostly detected in class III (76.92%), followed by class II (76.66%), and class I (54.87%). In the analyzed CBCT scans, semi-lunar was the most common shape detected (42.85%), followed by triangular (30.82%), circular (18.04%), and tear-drop (8.27%). The depth of MDMR was not significantly different between three sagittal groups and between genders; however, the width of MDMR was higher in class III group and in male patients. In the present study, MDMR was found to be more common in patients with class II and class III skeletal classifications. Although, MDMR was more frequent in class III, the difference between class II and class III was not significant. Conclusion: More caution is needed during orthognatic surgery in patients with dentoskeletal deformities during the splitting of the ramus. Moreover, higher width of MDMR in class III and male patients should be concerned when planning an orthognatic surgery for these patients.

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