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1.
J Hum Evol ; 168: 103210, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35617847

RESUMO

Differences in morphology among modern humans and African apes are frequently used when assessing whether hominin fossils should be attributed to a single species or represent evidence for taxic diversity. A good understanding of the degree and structure of the intergeneric, interspecific, and intraspecific variation, including aspects such as sexual dimorphism and age, are key in this context. Here we explore the variation and differences shown by the maxilla of extant hominines, as maxillary morphology is central in the diagnosis of several hominin taxa. Our sample includes adults of all currently recognized hominine species and subspecies, with a balanced species sex ratio. In addition, we compared the adults with a small sample of late juveniles. The morphology of the maxillae was captured using three-dimensional landmarks, and the size and shape were analyzed using geometric morphometric methods. Key observations are that 1) the maxillae of all extant hominine species and subspecies show statistically significant differences, but complete separation in shape is only seen at the genus level; 2) the degree of variation is not consistent between genera, with subspecies of Gorilla being more different from each other than are species of Pan; 3) the pattern of sexual shape dimorphism is different in Pan, Gorilla, and Homo, often showing opposite trends; and 4) differentiation between maxillary shapes is increased after adjustment for static intraspecific allometry. These results provide a taxonomically up-to-date comparative morphological framework to help interpret the hominin fossil record, and we discuss the practical implications in that context.


Assuntos
Hominidae , Animais , Fósseis , Gorilla gorilla/anatomia & histologia , Hominidae/anatomia & histologia , Humanos , Maxila/anatomia & histologia , Caracteres Sexuais
2.
BMC Oral Health ; 22(1): 166, 2022 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-35524244

RESUMO

BACKGROUND: A thorough understanding of the original root and canal anatomy is a critical technical prerequisite for performing cleaning and shaping treatments. Therefore, this research aimed to characterize maxillary first premolar teeth' root morphology and canal architecture. METHODS: One hundred forty-two extracted human adult maxillary first premolar teeth have been retrieved. The extracted teeth were thoroughly cleaned and irrigated to eliminate any remaining debris or blood. They were then preserved in formalin solution until they were eligible for screening. To begin, a visual examination was employed to ascertain the number of roots and their geometry in each sample. Then, utilizing digital radiography in two plains, mesiodistal and distomesial, to further determine those parameters. Finally, a sectioning technique had been used to have the samples cut mesiodistally into slices to validate the internal root canal architecture and identify the number of root canals and their varieties in accordance with Vertucci's categorization system. The canal layout, the pulp chamber, and the root canals were all highlighted (marked) using a fine tip marker in a permanent orange hue to make the canal features more accessible and accurate to visualize. All of the processes were conducted by two highly qualified dentists. The sample size was estimated statistically using the Sealed Envelope program, and the percentage of each configuration was derived in proportion to the overall sample size in order to establish the percentage of each type in each configuration. RESULTS: From the 142 teeth examined, 42 (29.57%) had one root, 97 (68.31%) had two roots, and only three premolars (2.12%) had three roots. Concerning canal configurations, 100 teeth (70.43%) had type (IV) canal configuration, followed by 37 teeth (26.05%) had types (V), three teeth (2.12%) had type (VIII), and one tooth (0.70%) for each of type (I) and type (II). CONCLUSIONS: The anatomical pattern of inspected maxillary first premolars are mainly two rooted and predominantly have a type (IV) canal morphology.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Raiz Dentária , Adulto , Dente Pré-Molar/anatomia & histologia , Dente Pré-Molar/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico/métodos , Cavidade Pulpar/anatomia & histologia , Cavidade Pulpar/diagnóstico por imagem , Humanos , Maxila/anatomia & histologia , Maxila/diagnóstico por imagem , Radiografia Dentária Digital , Raiz Dentária/anatomia & histologia , Raiz Dentária/diagnóstico por imagem
3.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 57(4): 352-357, 2022 Apr 09.
Artigo em Chinês | MEDLINE | ID: mdl-35368161

RESUMO

Objective: To explore the relationship between the width ratios of maxillary anterior teeth, the width/height ratios of maxillary central incisor and the esthetic proportions among individual normal occlusion, and to provide reference for the esthetic design of anterior teeth. Methods: A total of 300 Shanxi Medical University students who were residents from Shanxi province with normal occlusion (110 males, 190 females, aged 18-30 years) were recruited in this study from October 2020 to March 2021. Standardized digital photographs of the maxillary anterior tooth in natural head position were obtained, the perceived width of the maxillary anterior teeth (maxillary central incisors, lateral incisors and canines) on the left and right sides and height of maxillary central incisor were measured on the standardized digital photographs, then the width ratios of adjacent maxillary anterior teeth including the lateral incisor/central incisor width ratio (LI∶CI), the canine/lateral incisor width ratio (C∶LI), and the width/height ratios (W/H ratio) of the maxillary central incisor were calculated. The independent sample t test was used to compare the sex differences of each measurement project, Single sample t test was used to compare the difference of adjacent maxillary anterior teeth width ratios with golden proportion (0.618 and 0.618), Preston proportion (0.66 and 0.84), the recurring esthetic dental (RED) proportion (0.70 and 0.70). The percentage of anterior tooth width/intercanine width was calculated, the number and proportion of teeth conforming to golden percentage (25%, 15%, 10%)±1% or modified golden percentage (22.5%, 15.0%, 12.5%)±1% were calculated. The number and proportion of width/height ratio of maxillary central incisor ranged from 0.75 to 0.85 was counted. Results: The widths of maxillary central incisor, lateral incisor and canine were (8.50±0.52), (6.23±0.53) and (5.18±0.55) mm, respectively, the corresponding tooth of male [(8.74±0.49), (6.37±0.52), (5.41±0.47) mm] was significantly higher than that of female [(8.37±0.50), (6.15±0.52), (5.04±0.54) mm] (t=6.40, 3.55, 6.23,P<0.05). The width ratio of maxillary lateral incisor/central incisor was 0.73±0.05, and there was no significant difference between genders (t=-1.06, P>0.05). The width ratio of canine/lateral incisor was 0.84±0.10, and it was significantly higher in male (0.85±0.10) than in female (0.82±0.10) (t=2.42, P<0.05). Two width ratios of maxillary anterior teeth were significantly different from golden proportion and the RED proportion (t=38.50, 35.74, 11.48, 22.20, P<0.05). The lateral incisor/central incisor was significantly different from that of Preston proportion (t=24.66, P<0.05), while the canine/lateral incisor was not significantly different from that of Preston proportion (t=-0.92, P>0.05). In this study, a total of 0% (0/600) of central incisors, 63.0% (378/600) of lateral incisors and 5.8% (35/600) of canines met the golden percentage±1%. There were 42.8% (257/600) of central incisors, 63.0% (378/600) of lateral incisors and 56.7% (340/600) of canines met the modified golden percentage±1%. The width/height ratio of maxillary central incisors was 0.86±0.08, and there was no significant difference between genders (t=-0.88, P>0.05). Only 36.3% (218/600) of the subjects in this study ranged from 0.75 to 0.85. Conclusions: Gender differences should be considered in the esthetic design of anterior teeth; for the width ratios of maxillary anterior teeth, the golden proportion, the RED proportion and golden percentage do not accord with the natural tooth morphological characteristics of Shanxi nationality college students in normal occlusion. Preston proportion and modified golden percentage are of more reference value. The width/height ratio of maxillary central incisors is different from 0.75-0.85.


Assuntos
Dente Canino , Estética Dentária , Dente Canino/anatomia & histologia , Feminino , Humanos , Masculino , Maxila/anatomia & histologia , Odontometria , Estudantes
4.
Stomatologiia (Mosk) ; 101(1): 66-69, 2022.
Artigo em Russo | MEDLINE | ID: mdl-35184536

RESUMO

OBJECTIVE: High precise evaluation of the nasopalatine canal morphology is essential to perform detailed diagnosis and treatment plans in implantology and the orthodontic field. We aimed to study morphometric analysis measurements of the nasopalatine canal. MATERIAL AND METHODS: In this cross-sectional study, maxillary CBCT images from 125 patients were evaluated in the Maxillofacial Radiology department between 2014-2021. Sagittal views were assessed to determine nasopalatine canal morphology and dimensions. The difference in canal diameter and length between genders was evaluated using an One Way ANOVA test. RESULTS: There was no significant sex difference among all 125 cases in nasopalatine canal diameter, length, anterior bone plate width. The average length of the nasopalatine canal was 16.49±2.8 mm in male, 16.20±2.9 mm in female, incisive foramen diameter in the sagittal plane was 4.04±0.9 mm in male, 4.02±0.9 mm in female, nasopalatine foramen diameter was 4.63±1.4 mm in male, 4.75±1.2 mm in female. The width of the bone anterior to the canal was 5.89±1.4 mm in males, 5.69±1 mm in females. CONCLUSION: 16-48 aged Mongolian average length of the nasopalatine canal was 16.3 mm, and average incisive foramen width was 4.08 mm, the average width of the bone anterior to the canal was 5.76 mm. Anterior retraction treatment for upper incisor root can be done safely without root resorption around 5.5 mm in the premaxillary alveolar bone.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Maxila , Idoso , Estudos Transversais , Assistência Odontológica , Feminino , Humanos , Masculino , Maxila/anatomia & histologia , Maxila/diagnóstico por imagem , Raiz Dentária
5.
ScientificWorldJournal ; 2022: 7226998, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35185395

RESUMO

BACKGROUND: Initial bone thickness has a substantial impact on the success of dental implant treatments. The objective of the current study was to analyze the thickness of the buccal and alveolar bone at the central incisors using CBCT in relation to gender and side to determine the anatomical features and choose the best implant treatment option for minimizing the surgical complications. METHODS: One hundred CBCT images were investigated (50 females and 50 males, aged 20 to 50 years old). The buccal bone thickness and alveolar bone thickness were evaluated for right and left sides of each subject at three sites; C: crest (3 mm); M: middle (6 mm); A: apical (9 mm) from the cementoenamel junction. RESULTS: The mean thickness of buccal bone was less than 2 mm on the incisors according to side and gender. Buccal bone thickness revealed a statistically significant difference between right and left sides at the apical point in both females and males with p values of (p ≤ 0.001) and (0.001), respectively. The buccal bone thickness displayed statistically significant differences between genders at all sites. The alveolar thickness demonstrated similar significant differences between genders except for the crest site. CONCLUSIONS: Iraqi participants had about 1 mm buccal bone thickness at 3 mm apical from the CEJ in right and left central incisors with a progressive rise in bone thickness to be less than 2 mm at the apex. Alveolar bone also showed the same increase in bone thickness from crest to apex. Bone thickness was greater in males than females. The present study provided valuable CBCT data on bone thickness of the esthetic maxillary region as a preoperative analysis for establishing an immediate implant treatment plan with aesthetically pleasing long-term outcomes.


Assuntos
Processo Alveolar/diagnóstico por imagem , Incisivo/diagnóstico por imagem , Maxila/diagnóstico por imagem , Adulto , Processo Alveolar/anatomia & histologia , Tomografia Computadorizada de Feixe Cônico , Feminino , Humanos , Incisivo/anatomia & histologia , Iraque , Masculino , Maxila/anatomia & histologia , Pessoa de Meia-Idade , Adulto Jovem
6.
Biomed Res Int ; 2022: 8381436, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35187172

RESUMO

INTRODUCTION: We aimed (1) to measure the mesiodistal and buccolingual widths of the permanent dentition in Iranian orthodontic patients, (2) to determine cut-off points for sex identification based on the mesiodistal and buccolingual diameters, and (3) to calculate Bolton indices. METHODS: The mesiodistal and buccolingual dimensions of 28 maxillary and mandibular permanent teeth in 331 Iranian nonsyndromic orthodontic patients (dental casts and radiographs) aged 12 to 35 years old with fully erupted permanent dentitions (except the third molars and some sporadic cases of a few teeth missing or excluded) were measured. The anterior, posterior, and overall Bolton ratios were calculated in cases with no missing teeth in the 6-to-6 range. Potentially associated factors (the skeletal Angle classes, crowding, sex, jaws, sides, and age), as well as the value of these measurements for sex determination and cut-off points for sex identification based on these measurements were assessed using receiver-operator characteristic (ROC) curves, analysis of variance (ANOVA), Tukey, unpaired t-test, partial and Pearson correlation coefficients, and multiple linear regression (α = 0.05). RESULTS: Sex dimorphism was very frequent (P ≤ 0.05 in 41 out of 56 measurements). Only the buccolingual widths of the maxillary lateral and the mandibular central and lateral differed across the Angle classes (ANOVA/Tukey, P < 0.05). Cut-off points were estimated for 38 dental measurements, which were proper for sex identification (P < 0.05), with 8 (2 maxillary and 6 mandibular) measurements being highly appropriate (having areas under ROC curves ≥ 64%, P < 0.05). Both the mandibular canines were the only teeth with all four measurements highly appropriate for this purpose. Controlling for the role of sex, aging was associated negatively with several crown dimensions (the buccolingual widths of the maxillary first and second premolar and mandibular second premolar and first molar; the mesiodistal diameters of the maxillary central, canine, first premolar, and first molar, mandibular central, lateral, first premolar, and first molar, P ≤ 0.05, partial correlation coefficient). There were significant correlations among crown sizes. All the 28 (right/left-averaged) measurements were smaller in microdontia cases (P ≤ 0.002). The anterior, posterior, and overall Bolton indices were 78.05, 105.42, and 91.87, respectively. There were correlations between the overall Bolton ratio with the other two Bolton ratios (Pearson R = 0.696, R = 0.740, P < 0.0005) but not between the anterior and posterior Bolton ratios (R = 0.045, P = 0.459). The skeletal Angle classes might not be associated with the overall and anterior Bolton ratios (ANOVA, regression, Pearson, P > 0.05). However, the posterior Bolton ratio was smaller in class II cases compared to classes I or III (Tukey, P ≤ 0.045). In the whole sample, there was no sex dimorphism in Bolton ratios (t-test, P > 0.05). However, in Angle class II patients, the anterior Bolton ratio was greater in men than in women (P = 0.014). CONCLUSIONS: Sex dimorphism might be very common in the dentition of Iranians, with aging significantly reducing some measurements. The buccolingual widths of some incisors might differ across the skeletal Angle classes. Mandibular canines are the most appropriate teeth for sex identification. The Angle classes might not be associated with the anterior and overall Bolton ratios; nevertheless, the posterior Bolton ratio might be smaller in class II cases compared to others. In general, sex might not affect Bolton ratios; however, in class II patients, the anterior Bolton ratios might be larger in men.


Assuntos
Dentição Permanente , Odontometria/métodos , Caracteres Sexuais , Dente/anatomia & histologia , Adolescente , Adulto , Criança , Feminino , Humanos , Irã (Geográfico) , Masculino , Mandíbula/anatomia & histologia , Maxila/anatomia & histologia
7.
Plast Reconstr Surg ; 149(4): 731e-742e, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35171849

RESUMO

BACKGROUND: Visual impairment secondary to orbital and periorbital dysmorphology is frequent in Pfeiffer syndrome patients. The etiopathogenesis of this aberrancy, however, remains unclear. METHODS: Untreated Pfeiffer syndrome patients (n = 31) and normal control subjects (n = 43) were compared. Craniometric and volumetric analyses related to the orbital and periorbital anatomy were performed using Materialise (Leuven, Belgium) software. RESULTS: Overall, orbital cavity volume of Pfeiffer patients is reduced by 28 percent (p < 0.001), compared to normal, starting before 3 months of age (p = 0.004). Globe volume was diminished by 10 percent (p = 0.041) before 3 months of age, yet tended to catch up thereafter. However, the retrobulbar soft-tissue volume remained smaller beyond 1 year of age (17 percent, p = 0.003). Globe volume projection beyond the bony orbit increased in all observed ages (82 percent, p < 0.001). The volumes of sphenoid bone, maxilla, and mandible proportionately were restricted by 24 to 25 percent (p = 0.003 to 0.035) before 3 months of age. The volume of maxilla and mandible gradually approximate normal; however, the sphenoid bone volume in Pfeiffer patients remains less than normal (p = 0.002) into childhood. The anteroposterior length of both the zygoma and the maxilla was reduced by 14 percent (p < 0.001). Anterior positioning of the zygoma is less by 23 percent (p < 0.001) in Pfeiffer patients overall, with anterior positioning of maxilla reduced similarly by 23 percent (p < 0.001). CONCLUSIONS: Pfeiffer syndrome patients develop decreased retrobulbar soft-tissue and globe volume, along with a restricted orbital cavity volume in infancy. Significant hypoplasia of the sphenoid bone is associated with more severe central facial (maxilla) retrusion, compared to lateral facial structures (zygoma). CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, II.


Assuntos
Acrocefalossindactilia , Acrocefalossindactilia/complicações , Acrocefalossindactilia/diagnóstico por imagem , Cefalometria , Criança , Humanos , Maxila/anatomia & histologia , Órbita/anormalidades , Zigoma
8.
Pain Physician ; 25(1): E127-E132, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35051160

RESUMO

BACKGROUND: Previous studies of variations of the infraorbital foramen (IOF) demonstrated conflicting results regarding to the side and gender in which specific variations occur. Significant differences in some measurement points between genders have been found, whereas, other studies did not report such differences. The presence of an accessory IOF (AIOF) can result in incomplete anesthesia or treatment failure. Previous studies have demonstrated variable results regarding the prevalence of an AIOF ranging from 16.9% to 47.6%. OBJECTIVES: The purpose of this study was to perform a morphological and morphometric study of the IOF and AIOF based on images of 3-dimensional (3D) facial bone computed tomography (CT) scans. STUDY DESIGN: Retrospective study. METHODS: Identification and analysis of patients who have undergone facial bone 3D CT were performed using Clinical Data Warehouse v 2.5 (CDW, Planit Healthcare, Seoul, Korea). The search term that we used with the CDW for analysis was "facial bone 3D CT."First, the region below the infraorbital rim was examined to determine the presence of the IOF and AIOF. Second, the shape of the IOF was determined and categorized as circular or oval. Third, the vertical (VD) and horizontal (HD) diameters of the IOF were determined. Lastly, the distances between important anatomic landmarks and the IOF were measured. RESULTS: A single IOF with a circular shape was most common. The HD and VD of the IOF were significantly larger in men than in women. The distance between the IOF and the infraorbital margin was similar between men and women. The distances measured from the lateral nasal aperture (LNA) to the IOF and the anterior nasal spine (ANS) to the IOF, at both sides, were significantly shorter in women than in men. The prevalence of the AIOF on the right and left side was 7.3% and 8.9%, respectively. The most commonly observed position of the AIOF was on the inferior medial side of the IOF. LIMITATIONS: This study had an imbalance in the number of male and female patients. CONCLUSIONS: The size of the IOF was larger in men than in women. The distance of the IOF from the infraorbital margin was similar for men and women, whereas, the distances between the IOF and the ANS and the IOF and LNA were shorter in women than in men.


Assuntos
Maxila , Órbita , Feminino , Humanos , Masculino , Maxila/anatomia & histologia , Órbita/anatomia & histologia , Órbita/diagnóstico por imagem , República da Coreia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
9.
ScientificWorldJournal ; 2022: 4766305, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35087327

RESUMO

The aim of this study was to evaluate the root canal morphology of permanent maxillary molars by cone-beam computed tomography (CBCT) using the classifications of Weine et al. and Vertucci and to correlate the findings with sex, age, position in the dental arch, and prevalence of a second canal in the mesiobuccal root (MB2). A total of 414 scans were evaluated, corresponding to 1,000 teeth. The assessment consisted of coronal, axial, and sagittal reconstructions using i-CAT Workstation®. Type 0 was assigned when neither classification could be applied. The data were entered into an Excel spreadsheet and analyzed using SPSS. The chi-squared test or Fisher's exact test was used to compare the distribution of root canal morphology classified using the two systems. Analysis of the distribution of Weine types showed a predominance of type III in mesiobuccal roots, while type 0 predominated in distobuccal and palatal roots. Vertucci type IV predominated in mesiobuccal and distobuccal roots and type VII in palatal roots. There was no difference in the distribution of morphological canal types in permanent maxillary molars evaluated by CBCT according to sex, age group, or position in the dental arch of the patients. MB2 canals were identified in 68.4% of the teeth evaluated.


Assuntos
Variação Anatômica , Tomografia Computadorizada de Feixe Cônico/estatística & dados numéricos , Cavidade Pulpar/diagnóstico por imagem , Maxila/diagnóstico por imagem , Dente Molar/diagnóstico por imagem , Adolescente , Adulto , Idoso , Criança , Cavidade Pulpar/anatomia & histologia , Feminino , Humanos , Masculino , Maxila/anatomia & histologia , Pessoa de Meia-Idade , Dente Molar/anatomia & histologia
10.
Ear Nose Throat J ; 101(2): NP45-NP49, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32757996

RESUMO

OBJECTIVE: To study anterior nasal spine fractures, including the incidence, missed diagnosis rates, and relationship with shapes using computed tomography (CT). METHODS: Two hundred cases of axial CT images performed for maxillofacial trauma were reviewed. The incidence, correct, and missed diagnosis rates of anterior nasal spine fractures were studied. The relationship between the fracture and the shape of the anterior nasal spine was also analyzed. RESULTS: The rate of anterior nasal spine fractures was 22.00% (44 of 200). The diagnostic accuracy was 4.55% (2 of 44) and the missed diagnosis rate was 95.45% (42 of 44). The fracture rates of the double rod, single rod, triangle, and irregular anterior nasal spine were 33.85% (22 of 65), 32.26% (10 of 31), 12.24% (12 of 98), and 0.00% (0 of 6), respectively. The double and single rod types of anterior nasal spine were most likely to be fractured than the type of triangle (χ2 = 11.05, 6.67, P < .0167). No fracture was found in the irregular type of anterior nasal spine. CONCLUSION: Anterior nasal spine fractures are not rare and the high missed diagnostic rate results from unfamiliarity with the structure. Double and single rod types of anterior nasal spines are easy to fracture. Bony reconstruction and thin thickness of CT images are necessary for diagnosis.


Assuntos
Fraturas Maxilares/diagnóstico por imagem , Nariz/diagnóstico por imagem , Nariz/lesões , Tomografia Computadorizada por Raios X , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Incidência , Masculino , Maxila/anatomia & histologia , Maxila/diagnóstico por imagem , Fraturas Maxilares/epidemiologia , Fraturas Maxilares/etiologia , Pessoa de Meia-Idade , Diagnóstico Ausente , Nariz/anatomia & histologia , Adulto Jovem
11.
Med Sci Monit ; 27: e933450, 2021 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-34934039

RESUMO

BACKGROUND In the field of forensic medicine, sex estimation is a critical step in personal identification. Teeth are the hardest tissue and have high temperature resistance and corrosion resistance. In cases such as an airplane crash or the corpse of an unknown person, teeth often play a crucial role in identification. This study applied 3-dimensional technology to obtain odontometrics of permanent maxillary teeth and to examine the sexual dimorphism, finding suitable discriminant indicators to construct appropriate equations for sex estimation. MATERIAL AND METHODS A total of 204 participants (104 men and 100 women) from the Han population in Kashgar were included. Plaster models of their maxillary dentition were obtained to scan and measure through an accepted and commonly used 3-dimensional digital method. Descriptive statistics, t tests, and discriminant analyses were statistically analyzed using IBM SPSS 23.0 software. RESULTS This study showed high intra- and interexaminer reliability (intraclass correlation coefficient >0.950). There were statistically significant sex-related differences (P<0.05), with male values generally being higher for buccolingual distance, mesiodistal distance, intercanine distance, crown area, crown module, crown index, and maxillary canine index. Compared with other measurements, mesiodistal distance and crown area indicator exhibited distinct sexual dimorphism. In addition, several appropriate equations were constructed through different discriminant analyses that could be used to estimate sex in our specific population. CONCLUSIONS Three-dimensional digital technology offers a promising method for odontometry. Combining mesiodistal distance and buccolingual distance of particular teeth or using maxillary canine index in discriminant functions are acceptable auxiliary tools for sex estimation in the forensic field.


Assuntos
Imageamento Tridimensional , Maxila/anatomia & histologia , Odontometria/métodos , Adolescente , Adulto , Feminino , Humanos , Imageamento Tridimensional/métodos , Masculino , Caracteres Sexuais , Dente/anatomia & histologia , Adulto Jovem
12.
Dokl Biol Sci ; 501(1): 171-176, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34962601

RESUMO

The remains of the white-toothed shrew Crocidura kornfeldi Kormos, 1934 (one skull fragment with almost complete dentition, the fragmental rostral part of a skull with the left upper incisor, a maxillary fragment, five mandibular fragments and an isolated upper incisor) from the Lower Pleistocene deposits of the Taurida cave in the central Crimea (Belogorsk district, Zuya village) are described. This earliest European species of the genus Crocidura was quite common in the Early Pleistocene of Central Europe and the Mediterranean; for the first time, it is described from Crimea and the entire Eastern Europe.


Assuntos
Fósseis , Musaranhos , Animais , Europa (Continente) , Maxila/anatomia & histologia , Crânio
13.
Proc Natl Acad Sci U S A ; 118(44)2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-34716275

RESUMO

The anterior end of the mammalian face is characteristically composed of a semimotile nose, not the upper jaw as in other tetrapods. Thus, the therian nose is covered ventrolaterally by the "premaxilla," and the osteocranium possesses only a single nasal aperture because of the absence of medial bony elements. This stands in contrast to those in other tetrapods in whom the premaxilla covers the rostral terminus of the snout, providing a key to understanding the evolution of the mammalian face. Here, we show that the premaxilla in therian mammals (placentals and marsupials) is not entirely homologous to those in other amniotes; the therian premaxilla is a composite of the septomaxilla and the palatine remnant of the premaxilla of nontherian amniotes (including monotremes). By comparing topographical relationships of craniofacial primordia and nerve supplies in various tetrapod embryos, we found that the therian premaxilla is predominantly of the maxillary prominence origin and associated with mandibular arch. The rostral-most part of the upper jaw in nonmammalian tetrapods corresponds to the motile nose in therian mammals. During development, experimental inhibition of primordial growth demonstrated that the entire mammalian upper jaw mostly originates from the maxillary prominence, unlike other amniotes. Consistently, cell lineage tracing in transgenic mice revealed a mammalian-specific rostral growth of the maxillary prominence. We conclude that the mammalian-specific face, the muzzle, is an evolutionary novelty obtained by overriding ancestral developmental constraints to establish a novel topographical framework in craniofacial mesenchyme.


Assuntos
Evolução Biológica , Face/anatomia & histologia , Ossos Faciais/anatomia & histologia , Animais , Anuros/anatomia & histologia , Embrião de Galinha , Cabeça/anatomia & histologia , Arcada Osseodentária/anatomia & histologia , Lagartos/anatomia & histologia , Mamíferos , Mandíbula/anatomia & histologia , Maxila/anatomia & histologia , Camundongos , Camundongos Endogâmicos C57BL
14.
ScientificWorldJournal ; 2021: 8993734, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34650346

RESUMO

OBJECTIVES: This study aimed at finding out whether anterior teeth angulation and inclination have a relationship with the maxillary teeth and dental arch dimensions. METHODS: Fifty study models with normal occlusion were selected from the archive of the Department of Orthodontics at Baghdad Dental Faculty. Maxillary dental arch width and length at different points were determined in addition to measuring anterior teeth angulation, inclination, crown thickness, overjet, overbite, and Bolton's ratios. The unpaired t-test and Pearson's correlation coefficient test were used for data analysis. RESULTS: No statistical gender differences were reported in all measurements except the dental arch widths and length where males had significantly higher mean values. Only the maxillary incisor's inclination showed a direct weak significant correlation with the total arch length. CONCLUSIONS: The inclination of upper incisors had a minimal effect on increasing dental arch length.


Assuntos
Arco Dental/anatomia & histologia , Oclusão Dentária , Maxila/anatomia & histologia , Dente/anatomia & histologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
15.
PLoS One ; 16(9): e0257427, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34506601

RESUMO

Squamates are ideal subjects for investigating relationships between diet and dental patterns because they exhibit wide dietary diversity, marked variation in dental shape, and are taxonomically abundant. Despite this, well-established links between diet and dental morphology are primarily qualitative in nature, with specific patterns of squamate dental complexity remaining largely unknown. Here, we use quantitative methods and a broad taxonomic dataset to quantify key patterns in squamate dental morphology, including re-examining the relationship between dentition and diet, testing for differences in complexity between dentigerous elements, and exploring the effect of ontogenetic dietary shifts in dental complexity in two iguanid genera. Our findings support previous research by demonstrating that species consuming more plant material possess more complex teeth. We did not find significant complexity differences between the left and right dentigerous elements nor the upper and lower jaws, with the exception of Amblyrhynchus cristatus, the marine iguana, which possesses significantly more complex dentary teeth than premaxillary and maxillary teeth. We find discordant patterns when testing for dental complexity changes through ontogeny. Amblyrhynchus, which is primarily herbivorous throughout its lifetime, increases dental complexity through ontogeny, whereas Ctenosaura, which is generally insectivorous as juveniles and herbivorous as adults, decreases dental complexity. Although preliminary, this research documents and quantifies novel patterns of squamate dental complexity and exhibits the possibilities for further research on the diversity of squamate dental morphology.


Assuntos
Dentição , Dieta , Lagartos/anatomia & histologia , Lagartos/fisiologia , Dente/anatomia & histologia , Animais , Trato Gastrointestinal , Herbivoria , Arcada Osseodentária/anatomia & histologia , Mandíbula/anatomia & histologia , Maxila/anatomia & histologia , Especificidade da Espécie
16.
J Hum Evol ; 157: 103031, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34246049

RESUMO

Facial orientation (projection and degree of prognathism) and form in hominins is highly variable, likely related to evolutionary modifications of the microscopic process of bone modeling (the simultaneous cellular activities of bone formation and resorption) during ontogeny. However, in anteriorly projected faces such as those of early hominins, little is known about the link between bone modeling and facial developmental patterns. Similarly, these aspects have been infrequently investigated in extant great apes. In this study, quantitative methods were applied to a cross-sectional ontogenetic sample of 33 chimpanzees (Pan troglodytes verus) and 59 modern humans (Homo sapiens) to compare the development of maxillary prognathism to orthognathism at both microscopic and macroscopic (or morphological) scales using surface histology and geometric morphometric techniques. Chimpanzees express on average lower amounts of bone resorption than humans on the maxillary periosteum throughout ontogeny; however, the premaxilla is consistently resorbed from early stages on. The presence of bone resorption in the chimpanzee premaxilla, such as that seen in some early hominins, suggests a more ape-like pattern of maxillary bone modeling in these specimens. However, this shows that similarities in bone modeling patterns can lead to variations in shape, suggesting that other aspects of facial growth (such as modifications of rates and timings of development, as well as sutural growth) also played a crucial role in facial evolution.


Assuntos
Maxila/anatomia & histologia , Pan troglodytes/anatomia & histologia , Prognatismo , Adulto , Envelhecimento , Animais , Criança , Estudos Transversais , Feminino , Humanos , Masculino
17.
Biomed Res Int ; 2021: 5599949, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34124250

RESUMO

The growth and development of facial bones are closely related to each other. The present study investigated the differences in the nasomaxillary and mandibular morphology among different skeletal patterns. Cephalograms of 240 participants were divided into 3 groups based on the skeletal pattern (Class I, Class II, and Class III). The dimensions of nasomaxilla (nasal bone length, nasal ridge length, nasal depth, palatal length, and maxillary height) and mandible (condylar length, ramus length, body length, symphysis length, and entire mandibular length) were measured. One-way analysis of variance and Pearson's correlation test were used for statistical analysis. No significant differences were observed among the skeletal patterns in terms of nasal bone length, palatal length, maxillary height, or condylar length. Class II had a significantly shorter ramus, mandibular body, and entire mandibular length compared with those of Class I and Class III. Nasal ridge length exhibited a significant moderate correlated with nasal bone length (correlation coefficient: 0.433) and maxillary height (correlation coefficient: 0.535). The entire mandibular length exhibited a significant moderate correlated with ramus length (correlation coefficient: 0.485) and body length (correlation coefficient: 0.536). In conclusion, nasal and maxillary dimensions exhibited no significant difference among the 3 skeletal patterns. Mandibular body and entire mandibular lengths were significantly positively correlations with Class III skeletal patterns.


Assuntos
Cefalometria , Mandíbula/anatomia & histologia , Maxila/anatomia & histologia , Osso Nasal/anatomia & histologia , Adolescente , Adulto , Feminino , Humanos , Masculino
18.
PLoS One ; 16(6): e0253283, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34133463

RESUMO

AIM: Bone quality is evaluated using bone density for qualitative classification, a characteristic that may be delicate to evaluate. Contemporary implantology that relies on modern measurement techniques, needs a more quantitative estimate of the bone quality. MATERIALS AND METHODS: PubMed and EMBASE databases were searched with no time restriction. Clinical and radiographic studies reporting on alveolar ridge dimensions and its parameters in different areas of the dentate and edentulous jaws were included. A meta-analysis was performed using random effect models to report a combined mean for alveolar ridge and its parameters. Meta regression statistical tests were performed in order to identify differences in those outcome parameters. RESULTS: 30 studies were included. The majority of the selected studies (total of 27) used live human subjects and CBCT to analyze alveolar ridge dimensions and its parameters. Using the combined mean obtained from the meta-analysis, a typical portrait of the alveolar ridge was constructed, and a geometrically based quantitative bone classification proposed. The quantitative classification was found to match the existing qualitative classification. CONCLUSION: A geometry-based analysis was constructed that yields valuable insights on the bone type based on its components and on the dynamics of the dentate / edentulous states.


Assuntos
Arcada Osseodentária/anatomia & histologia , Processo Alveolar/anatomia & histologia , Processo Alveolar/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico , Humanos , Arcada Osseodentária/diagnóstico por imagem , Arcada Edêntula/diagnóstico por imagem , Arcada Edêntula/patologia , Mandíbula/anatomia & histologia , Mandíbula/diagnóstico por imagem , Maxila/anatomia & histologia , Maxila/diagnóstico por imagem
19.
Laryngoscope ; 131(11): E2764-E2769, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34142721

RESUMO

OBJECTIVES/HYPOTHESIS: The prevalence of tympanostomy tube surgery (TTS) in patients with a cleft deformity was investigated, in relation to cleft width and cleft type. STUDY DESIGN: Retrospective review of medical health records. METHODS: Retrospective review of medical health records. Seventy-eight patients with non-syndromic cleft deformity of the palate and/or alveolus and lip between 2003 and 2017 were investigated. All available medical documents were analyzed. The study group was divided into subgroups: 1) patients with isolated cleft palate (CP) and patients with a cleft palate with cleft lip and alveolus (CLP). 2) According to Veau's classification (I-IV), further subgroups were defined. Cleft width was measured using plaster cast models. RESULTS: TTS was performed in 55% of the patients (n = 43). Considering Veau's classification, TTS was conducted as follows: Veau I 65.2% (n = 15/23), Veau II 55.0% (n = 11/20), Veau III 47.6% (n = 10/21), and Veau IV 50.0% (n = 7/14). Cleft classifications, maxillary arch width, and absolute/relative cleft width had no statistical impact on TTS occurrence. Although no significant correlation could be found, patients in our study group with CP (Veau I and II) underwent TTS more often (60.5%, n = 26/43) than patients with CPL (Veau III and IV; 48.6%, n = 17/35) during a three-year follow-up. CONCLUSION: None of the cleft characteristics examined had a significant impact on the proportion of patients who received TTS. Nevertheless, patients with lower Veau classification and CP received tympanostomy tubes more often. Therefore, otolaryngologists and pediatricians treating children with cleft palate should maintain a high level of suspicion for chronic middle ear effusion, even in patients with small clefts. LEVEL OF EVIDENCE: 3 Laryngoscope, 131:E2764-E2769, 2021.


Assuntos
Encéfalo/anormalidades , Fenda Labial/complicações , Fissura Palatina/complicações , Ventilação da Orelha Média/estatística & dados numéricos , Otite Média com Derrame/cirurgia , Encéfalo/patologia , Estudos de Casos e Controles , Moldes Cirúrgicos/normas , Fenda Labial/classificação , Fenda Labial/diagnóstico , Fenda Labial/patologia , Fenda Labial/cirurgia , Fissura Palatina/classificação , Fissura Palatina/diagnóstico , Fissura Palatina/patologia , Fissura Palatina/cirurgia , Arco Dental/anatomia & histologia , Feminino , Seguimentos , Perda Auditiva/diagnóstico , Perda Auditiva/etiologia , Humanos , Lactente , Masculino , Maxila/anatomia & histologia , Ventilação da Orelha Média/métodos , Otite Média com Derrame/complicações , Otite Média com Derrame/diagnóstico , Otorrinolaringologistas , Pediatras , Prevalência , Estudos Retrospectivos
20.
Sci Rep ; 11(1): 13196, 2021 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-34162932

RESUMO

Although a functional relationship between bone structure and mastication has been shown in some regions of the rabbit skull, the biomechanics of the whole cranium during mastication have yet to be fully explored. In terms of cranial biomechanics, the rabbit is a particularly interesting species due to its uniquely fenestrated rostrum, the mechanical function of which is debated. In addition, the rabbit processes food through incisor and molar biting within a single bite cycle, and the potential influence of these bite modes on skull biomechanics remains unknown. This study combined the in silico methods of multi-body dynamics and finite element analysis to compute musculoskeletal forces associated with a range of incisor and molar biting, and to predict the associated strains. The results show that the majority of the cranium, including the fenestrated rostrum, transmits masticatory strains. The peak strains generated over all bites were found to be attributed to both incisor and molar biting. This could be a consequence of a skull shape adapted to promote an even strain distribution for a combination of infrequent incisor bites and cyclic molar bites. However, some regions, such as the supraorbital process, experienced low peak strain for all masticatory loads considered, suggesting such regions are not designed to resist masticatory forces.


Assuntos
Simulação por Computador , Mastigação/fisiologia , Modelos Biológicos , Coelhos/anatomia & histologia , Crânio/anatomia & histologia , Animais , Fenômenos Biomecânicos , Cefalometria , Análise de Elementos Finitos , Incisivo , Músculo Masseter/fisiologia , Maxila/anatomia & histologia , Maxila/fisiologia , Dente Molar , Coelhos/fisiologia , Crânio/fisiologia , Estresse Mecânico , Suporte de Carga
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