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1.
L G Farkas J C Posnick T M Hreczko G E Pron 《The Cleft palate-craniofacial journal》1992,29(4):318-324
Age-related growth changes in the nasolabial region were analyzed through six measurements taken between 1 year and 18 years of age in 1,593 North American Caucasians. By 1 year of age, the length of the cutaneous portion of the upper lip and the width of the nose showed the highest levels of development compared with their adult size, 80.3 and 79.5%, respectively. By 5 years, the developmental level of the nasolabial region except nasal tip protrusion approached their maturation level. Our nasal measurements indicated that growth of the nose between 5 and 18 years was significantly greater than that of the upper lip, which revealed significantly greater growth increments between 1 and 5 years of age. The cutaneous upper lip height reached its adult size in 3-year-old females (12.7 mm) and 6-year-old males (14.4 mm). Nose width and height were fully developed in females by age 12 and in males by age 14 or 15. Rapid growth occurred in the upper lip, nose height, and nasal tip protrusion between the ages of 1 and 4 years. Knowledge of these age-related morphologic variations within the nose and upper lip may be useful in planning the time and type of reconstructive surgery and in anticipating further change in the operated regions after the surgical reconstruction. 相似文献
2.
Age-related growth changes in the face and the relationships between its parts were calculated by using three vertical, two horizontal, and two projective surface measurements from 1,594 healthy North American Caucasians between 1 and 18 years of age. By 1 year, the width of the mandible was highly developed (80.2%) while its height reached only 66.6% of the eventual adult size. The mandible's height and width showed significant development between 1 and 5 years, while the face height, upper face height, face width, and the two face depth measurements exhibited continuous gradual growth after 5 years of age. In general, the face matured between 12 and 15 years in males and 2 years earlier in females. At 12 years, the upper face height, the mandible height, and the width of the face reached their mature size in females. At 15 years, the face height, mandible height, face width, and the depth of the mandible reached maturity in males. 相似文献
3.
Elias G Katsavrias Demetrios J Halazonetis 《American journal of orthodontics and dentofacial orthopedics》2005,128(3):337-346
INTRODUCTION: The purpose of this investigation was to study the shapes of the condyle and the glenoid fossa in patients with Class II Division 1, Class II Division 2, and Class III malocclusions. METHODS: Axially corrected tomograms of 189 patients were used (109 Class II Division 1, 47 Class II Division 2, and 33 Class III). Five points on the condyle and 7 on the outline of the fossa were digitized. Size was assessed by the centroid size of each structure, and measurements of shape were made by principal component analysis of the Procrustes residuals. RESULTS AND CONCLUSIONS: Inspection of the principal components of shape showed that shape variability of the condyle was mainly related to inclination of the condylar head; shape variability of the fossa was related to inclination of the eminence and fossa height. Centroid size was correlated to age in the Class III group only. Condylar and fossa shapes were found to be different between the groups; the Class III group had a more elongated and anteriorly inclined condylar head and a wider and shallower fossa. In the Class III group, the condyle was closer to the roof of the fossa. The 2 Class II divisions differed only in the position of the condyle in the fossa, which was situated more anteriorly in the Class II Division 1 group. 相似文献
4.
Spolidorio LC Spolidorio DM Holzhausen M Nassar CA Nassar PO 《Brazilian dental journal》2007,18(1):24-28
Cyclosporin A (CsA) is a potent immunosuppressor used in organ transplantation and in the management of various autoimmune diseases. Recent studies have shown that CsA stimulates deposition of cementum on root surfaces. The aim of this study was to evaluate the periapical cementum thickness and the apical foramen width in CsA-treated rats. Rats weighing 50 g were treated with a daily injection of 10 mg/kg body weight of CsA in the chow for 60 days. The cementum of the mandibular 1st molars was histologically and morphometricaly examined by analysis of 5-microm-thick serial buccolingual paraffin sections stained with hematoxylin and eosin. Histometric and stereologic analyses revealed the presence of large amounts of cementum in all root surfaces, particularly abundant in the periapical region and obliterating the foramen. The volume density of cementoblasts did not increase. Five to 90 days after the termination of CsA therapy, there was no reduction of cementum thickness. These results suggest that cementum deposition is not reversible after cessation of CsA treatment. 相似文献
5.
Amir LR Becking AG Jovanovic A Perdijk FB Everts V Bronckers AL 《Clinical oral implants research》2006,17(4):417-425
Vertical distraction osteogenesis has received considerable interest as a way to augment bone prior to implant placement. However, very little is known regarding the appropriate distraction protocols in the human mandible. In this study, we evaluate the effect of the distraction rate and the duration of neutrofixation on bone formation and closure of the gap in the human mandible. Vertical distraction was performed in the atrophic mandible of 16 edentulous patients, aged 62+/-6 years. The bone was distracted for approximately 10 mm at a rate of either 0.5 or 1 mm/day. Bone biopsies were taken after 7-20 weeks of neutrofixation. Histological analysis demonstrated newly formed bone in the distraction gap in all biopsies. The bone was predominantly of the woven type. After 10 weeks of neutrofixation, the gap was bridged by new bone in two out of three intact samples in the 0.5 mm/day group, but not in two intact samples of the 1 mm/day group. Histomorphometry revealed longer bone trabeculae (P=0.02) and a somewhat increased bone volume in the area where new bone formation started (P=0.07) in the group of patients having the 0.5 mm/day of distraction rate than in the 1 mm/day group. We conclude that in elderly patients, a distraction rate of 0.5 mm/day results in faster osteogenesis in the distraction gap than a rate of 1 mm/day. A minimum of 10 weeks of neutrofixation seems to be needed to close a 10 mm gap after cessation of distraction. 相似文献
6.
Effect of low masticatory function on condylar growth: a morphometric study in the rat. 总被引:2,自引:0,他引:2
S Kiliaridis B Thilander H Kjellberg N Topouzelis A Zafiriadis 《American journal of orthodontics and dentofacial orthopedics》1999,116(2):121-125
The aim of this study was to estimate the influence of functional alterations on the size of the mandibular condyle and to elucidate in detail, by means of histomorphometric analysis, the effect of changing the consistency of the diet on different portions of the condylar cartilage in growing rats. Forty growing rats were randomly divided into 2 groups. One group received the normal hard diet for rats; the other group received a standardized soft diet. The experimental period was 28 days. Ten animals from each group were used for gross morphometric analysis; the other 10 animals were used for histologic analysis of the condyle. The morphometric analysis of the condylar cartilage was based on the 25th, 50th, and 75th percentiles of the mediolateral sections of the condyles. The sections were divided into 3 parts: the anterior, intermediate, and posterior part; 4 measurements were performed in each. Significant differences were found in the condylar length and width between the groups, the soft diet group having a smaller condyle. The histomorphometric analysis of cartilage thickness showed significant differences between the 2 groups, being thinner in the anterior part and thicker in the posterior part of the condyle in the soft diet group. These routine histologic findings cannot explain the gross morphologic differences in the condylar size between the groups; this means that increased condylar cartilage thickness is not necessarily evidence of increased condylar growth. The results from this study indicate that a low masticatory function leads to decreased growth of the condyle and changes in the thickness of the cartilage. This may be the effect of an alteration in the stress distribution in the temporomandibular joint area, because of the absence of large masticatory forces. 相似文献
7.
Nery LR Moreira CR Cestari TM Taga R Damante JH 《Journal of applied oral science : revista FOB》2010,18(5):509-514
Objective
To analyze and to quantify morphological acinar postmortem changes in rat sublingual glands (SLG).Material and Methods
Fifty rats were divided into two groups of 25 animals each. Group I was used for morphological and morphometric evaluations and group II for the determination of gland density and processed gland volume. Acinar autolytic changes were studied at 0 (control group), 3, 6, 12 and 24 h postmortem periods. The morphometric analysis of the volume density (Vv) and total volume (VT) of intact (ia) and autolyzed (aa) acini was performed under light microscopy using a Zeiss II integration grid with 100 symmetrically distributed points.Results
Morphologically, temporal progressive nuclear alterations and gradual loss of the structural architecture of acinar cells were found. Regarding quantitative results, both the Vvaa and the Vvia showed statistically significant differences among all postmortem periods (p<0.05). Vvaa increased from 0.42% at 0 h to 75.84% at 24 h postmortem and Vvia decreased from 71.16% to 0% over the same period. For VTaa and VTia, no statistically significant differences occurred between 12-24 h and 0-3 h (p>0.05), respectively. Vtaa increased from 0.18 mm3 at 0 h to 38.17 mm3 at 12 h, while Vtia showed a decrease from 33.47 mm3 to 0 mm3 between 3-24 h postmortem. Data concerning VTaa were adjusted by twovariable linear regression, obtaining the equation: y=-3.54 + 3.38x (r2=0.90). The VTaa growth rate calculated by this equation was 3.38 mm3/h between 0-12 h.Conclusion
Acinar autolysis on rat SLG demonstrated the most significant signs during the first 6 h postmortem and was widely spread through the gland at 12 h. 相似文献8.
《Journal of cranio-maxillo-facial surgery》2023,51(2):107-116
In this retrospective case series, patients undergoing surgery to treat isolated orbital floor fractures were morphometrically analyzed. Cloud Compare was used to compare mesh positioning with a virtual plan, using the distance-to-nearest-neighbor method. To assess the accuracy of mesh positioning, a mesh area percentage (MAP) parameter was introduced and three distance ranges were defined as the outcome measures: the ‘high-accuracy range’ included MAPs at a distance of 0–1 mm from the preoperative plan; the ‘intermediate-accuracy range’ included MAPs at a distance of 1.1–2 mm from the preoperative plan; the ‘low-accuracy range’ included MAPs at a distance of >2 mm from the preoperative plan.To complete the study, morphometric analysis of the results was combined with clinical judgment (‘excellent’, ‘good’, or ‘poor’) of mesh positioning by two independent blind observers.In total, 73 of 137 orbital fractures met the inclusion criteria. In the ‘high-accuracy range’ the mean, minimum, and maximum MAP values were 64%, 22%, and 90%, respectively. In the ‘intermediate-accuracy range’, the mean, minimum, and maximum values were 24%, 10%, and 42%, respectively. In the ‘low-accuracy range’, the values were 12%, 1%, and 48%, respectively.Both observers classified 24 cases of mesh positioning as ‘excellent’, 34 as ‘good’, and 12 as ‘poor’.Within the limitations of the study, it seems that virtual surgical planning and intraoperative navigation has the potential to add quality to the repair of the orbital floor and, therefore, should be taken into consideration whenever appropriate. 相似文献
9.
Undifferentiated pleomorphic sarcoma of the orbital region 总被引:1,自引:1,他引:0
Müller-Richter UD Kohlhof JK Reichert TE Roldán JC 《The British journal of oral & maxillofacial surgery》2008,46(4):325-327
Undifferentiated pleomorphic sarcoma (formerly known as malignant fibrous histiocytoma) has been established as an entity in the WHO-classification of soft tissue tumors since 2002. Before this the term "malignant fibrous histiocytoma" has been a collective term for soft tissue malignancies that had no distinct components and included most soft tissue sarcomas (40%). With the new classification they account for only about 5%, and tumors arising in the head and neck contribute only about 1-3% of all undifferentiated pleomorphic sarcomas. We report a rare case in which the orbital region was involved. 相似文献
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12.
Microcracks and microdamage have been associated with bone remodelling. The aim of this study was to investigate the role of microcracks as a trigger for alveolar bone remodelling after the application of an orthodontic load. In 25 3-month-old male Danish land-race pigs, the lower right first molar was moved buccally with a force of 130 cN. The contralateral molar was not treated and was used as an internal control. After 1, 2, 4, 7 and 15 days of treatment, the regions containing the right and left molars were excised and en bloc stained in basic fuchsin. The presence of microcracks on the buccal and lingual sides of both treated and untreated teeth was detected and expressed as crack density (number/mm2). The buccal treated side showed significantly more cracks than the buccal untreated side at day 1. This difference was significantly larger than that observed at days 2, 7 and 15. The same side showed significantly more microcracks than the lingual treated side at day 1, and this difference was larger compared with that observed at days 4 and 15. The presence of more microcracks on the treated side than on the untreated side suggests a role for microcracks in the initiation of bone remodelling after orthodontic loading. The increased presence of microcracks on the side towards which the tooth was moved, and where bone resorption is usually observed, suggests that microcracks could represent the first damage induced by orthodontic force that has to be repaired by bone remodelling. Finally, the strain levels in the alveolar bone during the orthodontic load transfer in the experiment were examined by finite element (FE) analysis. Although this showed that the strains were very low (10-100 microstrain), it should be noted that occlusal loading was not taken into account. In addition, high-resolution microtomography of the alveolar bone/periodontal ligament (PDL) interface revealed that the actual surface of the alveolar bone was very rough, predisposing it to high local stress/strain peaks. 相似文献
13.
Sforza C Elamin F Dellavia C Rosati R Lodetti G Mapelli A Ferrario VF 《The Journal of craniofacial surgery》2012,23(1):198-202
The orbital region of subjects with Down syndrome (DS) has been scanty described so far. We wanted to detail the morphologic characteristics of the soft tissue orbital region in Italian and North Sudanese subjects with DS. The three-dimensional coordinates of 10 landmarks on the orbital soft tissues were obtained using computerized anthropometry in 53 Italian and 64 North Sudanese subjects with DS aged 4 to 52 years, and in 461 (Italian) and 682 (North Sudanese) sex- and age-matched controls. From the landmarks, linear distances, ratios, areas, and angles were calculated, z scores computed, and compared by t-tests and analyses of covariance. In North Sudanese DS subjects, intercanthal width and height-to-length ratio were increased; biorbital width, eye height, length, and area were reduced. Eye fissure and orbital inclinations relative to Frankfort plane were reduced, whereas orbital inclinations versus the true horizontal were increased. In Italian DS men, orbital height and height-to-length ratio were increased, eye length was decreased; orbital inclination versus the true horizontal was increased. For almost all measurements, a significant effect of age was found. No effects of sex were found. Ethnic group influenced orbital height, area, and orbital inclination versus Frankfort plane. All paired measurements had similar discrepancies on both sides. The orbital soft tissues of North Sudanese DS subjects differed from those of their reference subjects, but this was only partially true for Italian subjects. The 2 ethnic groups had different alterations in their soft tissue orbital regions that were influenced by age, but not by sex. 相似文献
14.
Ozdemir H, Kara MI, Erciyas K, Ozer H, Ay S. Preventive effects of thymoquinone in a rat periodontitis model: a morphometric and histopathological study. J Periodont Res 2012; 47: 74–80. © 2011 John Wiley & Sons A/S Background and Objective: Thymoquinone has a variety of pharmacologic properties, including antihistaminic, antibacterial, antihypertensive, hypoglycemic, anti‐inflammatory and anti‐oxidative activities. Through its anti‐inflammatory and antioxidant properties, thymoquinone may play an important role in preventing periodontal diseases. The aim of this study was to evaluate the effectiveness of thymoquinone in preventing the initiation and progression of periodontitis in a rat periodontitis model. Material and Methods: Twenty‐four rats were randomly divided into three experimental groups: a nonligated (NL) treatment group (n = 8), a ligature‐only (LO) treatment group (n = 8) and a ligature plus thymoquinone (10 mg/kg, daily for 11 d) (TQ) treatment group. In order to induce experimental periodontitis, a 4/0 silk suture was placed at the gingival margin of the right‐mandibular first molars of the rats. Thymoquinone was administered by gastric feeding until the animals were killed on day 11. Changes in the alveolar bone levels of rats in each group were measured clinically, and tissues of rats in each group were examined histopathologically to determine inflammatory cell infiltration (ICI), osteoblast and osteoclast activities, and osteoclast morphology. Results: Alveolar bone loss around the mandibular molar tooth was significantly higher in the LO group compared with NL and TQ groups (p < 0.05). The ratio of the presence of ICI and osteoclast numbers was significantly higher in the LO group than in the NL and TQ groups (p < 0.05). Osteoblastic activity was significantly lower in the LO group than in the NL and TQ groups (p < 0.05). Conclusion: The present study showed that the oral administration of thymoquinone diminishes alveolar bone resorption in a rat periodontitis model. 相似文献
15.
Two groups of females, one with normal anteroposterior jaw-base relationships and the other with distal jaw-base relationships, were selected at age 6 and compared longitudinally up to age 18. The purposes of this study were, first, to reveal morphological factors that caused or contributed to a distal jaw-base relationship, and second, to compare growth in the two groups. A distal jaw-base relationship is not a morphological entity caused by some specific aberration in the cranial base or jaws. Rather, it is the result of a combination of predisposing deviations with varying degrees of gravity. A short mandibular corpus and a large MP-SN angle were the only deviations with significant group differences. Distal jaw-base relationships generally worsened with age as compared with normal anteroposterior jaw-base relationships. Inadequate increase in mandibular corpus length in the 6- to 12-year period contributed to the worsening, as did the mandible growing more vertically than normal after age 12. 相似文献
16.
M. Sashima 《Journal of oral pathology & medicine》1986,15(10):507-512
Age changes of the submandibular glands (SMG) of male rats were studied morphometrically and ultrastructurally from youth to old age. The most conspicuous feature of the aged SMG was regressive changes of the granular ducts. The extent and height of the granular ducts decreased as well as the content of mature secretory granules. These changes may play an important role for an individual rat, because the granular duct synthesizes many biological factors. Cytoplasmic crystalloids, salivary deposits and oncocytic transformation were also found in the SMG of rats more than 22-months-old. It was noticeable that the intercalated duct cells were especially affected by both crystalloid formation and oncocytic transformation. 相似文献
17.
M Sashima 《Journal of oral pathology》1986,15(10):507-512
Age changes of the submandibular glands (SMG) of male rats were studied morphometrically and ultrastructurally from youth to old age. The most conspicuous feature of the aged SMG was regressive changes of the granular ducts. The extent and height of the granular ducts decreased as well as the content of mature secretory granules. These changes may play an important role for an individual rat, because the granular duct synthesizes many biological factors. Cytoplasmic crystalloids, salivary deposits and oncocytic transformation were also found in the SMG of rats more than 22-months-old. It was noticeable that the intercalated duct cells were especially affected by both crystalloid formation and oncocytic transformation. 相似文献
18.
Measurement of orbital volume by a 3-dimensional software program: an experimental study. 总被引:4,自引:0,他引:4
M Deveci S Oztürk M Sengezer Y Pabu?cu 《Journal of oral and maxillofacial surgery》2000,58(6):645-648
PURPOSE: This study reports a simple method with high accuracy for determining orbital volume from computed tomography (CT) scans. MATERIALS AND METHODS: The volume of 20 orbits was evaluated in 20 dry skulls by use of a 3-dimensional software program in General Electric High-Speed Advantage CT/I (Milwaukee, WI), and compared with the volume obtained by direct measurement using the water displacement method. Accuracy of volume measurement by this software program was assessed statistically by paired samples t-test. RESULTS: The mean volume was found to be 28.37 mL +/- 2.15 by direct impression and 28.41 mL +/- 2.09 by the software program. Volume difference between the 2 methods averaged 0.93 +/- 1.08 mL for each orbit (P < .01). The correlation between the techniques was found to be high (r = 0.887, P < .01). There was no significant volume discrepancy between the 2 methods. CONCLUSION: Measurement by the technique described is an easy and accurate method of assessing the volume of the orbit. 相似文献
19.
R. Schreurs L. Dubois A.G. Becking T.J.J. Maal 《International journal of oral and maxillofacial surgery》2018,47(3):395-402
Intraoperative navigation is frequently used to assess the position of the implant in orbital reconstruction. Interpretation of the feedback from the navigation system to a three-dimensional position of the implant needs to be done by the surgeon, and feedback is only gathered after the implant has been positioned. An implant-oriented navigation approach is proposed, with real-time intuitive feedback during insertion. A technical framework was set up for implant-oriented navigation, with requirements for planning, implant tracking, and feedback. A dedicated navigation instrument was designed and a software tool was developed in order to meet the technical requirements. An accuracy study was performed to investigate the accuracy of the method in comparison to the regular navigation pointer. A proof of concept was provided. The results showed a translation error of 1.12–1.15 mm for implant-oriented navigation with regular registration (pointer 0.71–0.98 mm) and 0.81 mm with accurate registration (pointer 0.54 mm). Rotational error was found to be small (<3°). Quantitative and intuitive qualitative feedback could be provided to the surgeon in real-time during insertion of an orbital implant. Following this proof of concept and accuracy study, the implications for the clinical workflow should be evaluated. An implant-oriented approach may form the foundation for augmented reality or robotic-aided implant insertion. 相似文献