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180 result(s) for "Maxillary Sinus - growth "
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Development of maxillary sinuses in relation to the development of cranium in children on computed tomography imaging
There are available studies assessing the development of maxillary sinuses in relation to the viscerocranium. However, there are no publications analyzing the development of maxillary sinuses in relation to the development of the cranium, i.e. both the viscerocranium and the neurocranium. The aim of the study was to analyze the correlation between the dimensions of maxillary sinuses and anthropometric measurements of the cranium in children. The study was retrospective and was conducted at the based on the results of head computed tomography investigation. The study group included 180 girls and 180 boys, aged from birth to 18 years. To assess the correlation between the degree of development of the paranasal sinuses and the growth of the cranium, standard anthropometric points on the skull and strictly defined dimensions of the height, length, width, and volume of right and left maxillary sinuses were used. In the study group, both in girls and boys, a statistically significant positive correlation was found at the significance level of p  < 0.0001 between: the height, length, width and volume of right and left maxillary sinuses, and cranial maximum length (glabella-opisthocranion), its maximum width (euryon-euryon), height (basion-bregma) and the length of the cranial base (basion-nasion) and the dimension of the subspinale-opisthocranion in children. Our study showed a statistically significant positive correlation between the development of maxillary sinuses and the growth of the cranium in children.
Efficacy of Alveolar Ridge Preservation after Maxillary Molar Extraction in Reducing Crestal Bone Resorption and Sinus Pneumatization: A Multicenter Prospective Case-Control Study
Aim. To evaluate, with three-dimensional analysis, the effectiveness of alveolar ridge preservation (ARP) after maxillary molar extraction in reducing alveolar bone resorption and maxillary sinus pneumatization when compared to unassisted socket healing. Methods. Patients were included in the study following inclusion criteria and underwent minimally traumatic maxillary molar extraction followed by ARP using synthetic nanohydroxyapatite (Fisiograft Bone, Ghimas, Italy) (test group) or unassisted socket healing (control group). Cone-beam computerized tomographies (CBCT) were performed immediately after tooth extraction (T0) and 6 months postoperatively (T1). CBCTs were superimposed by using a specific software (Amira, Thermo Fisher Scientific, USA) and the following items were analyzed in both groups: (i) postextractive maxillary sinus floor expansion in coronal direction and (ii) postextractive alveolar bone dimensional changes (both vertical and horizontal). All data were tested for normality and equality of variance and subsequently analyzed by independent samples T-test and Mann–Whitney test. Results. Thirty patients were treated by three centers and twenty-six (test n=13; control n=13) were included in the final analysis. Mean sinus pneumatization at T1 was 0.69±0.48 mm in the test group and 1.04±0.67 mm in the control group (p=0.15). Mean vertical reduction of the alveolar bone at T1 was 1.62±0.49 mm in the test group and 2.01±0.84 mm in the control group (p=0.08). Mean horizontal resorption of crestal bone at T1 was 2.73±1.68 mm in test group and 3.63±2.24 mm in control group (p=0.24). Conclusions. It could be suggested that ARP performed after maxillary molar extraction may reduce the entity of sinus pneumatization and alveolar bone resorption, compared to unassisted socket healing. This technique could decrease the necessity of advanced regenerative procedures prior to dental implant placement in posterior maxilla.
Automatic maxillary sinus segmentation and age estimation model for the northwestern Chinese Han population
Background Age estimation is vital in forensic science, with maxillary sinus development serving as a reliable indicator. This study developed an automatic segmentation model for maxillary sinus identification and parameter measurement, combined with regression and machine learning models for age estimation. Methods Cone Beam Computed Tomography (CBCT) images from 292 Han individuals (ranging from 5 to 53 years) were used to train and validate the segmentation model. Measurements included sinus dimensions (length, width, height), inter-sinus distance, and volume. Age estimation models using multiple linear regression and random forest algorithms were built based on these variables. Results The automatic segmentation model achieved high accuracy, which yielded a Dice similarity coefficient (DSC) of 0.873, an Intersection over Union (IoU) of 0.7753, a Hausdorff Distance 95% (HD95) of 9.8337, and an Average Surface Distance (ASD) of 2.4507. The regression model performed best, with mean absolute errors (MAE) of 1.45 years (under 18) and 3.51 years (aged 18 and above), providing relatively precise age predictions. Conclusion The maxillary sinus-based model is a promising tool for age estimation, particularly in adults, and could be enhanced by incorporating additional variables like dental dimensions.
The Association between Maxillary Sinus Dimensions and Midface Parameters during Human Postnatal Growth
Objective. The aim of the study based on CT images was to assess the age-related changes in maxillary sinus diameters in relation to diameters of the facial skeleton. Materials and Methods. The retrospective analysis of CT images of the head of 170 patients aged 0–18 years (85 females and 85 males) was performed. Specific orientation points (zy, zm, pr, ns, n, and P) were identified in every patient and the following distances were measured: zy-zy, maximum facial width; zm-zm, midfacial width; n-pr, upper facial height; ns-pr, alveolar facial height; and ns-P, distance not indicated in craniometry. Results. The maxillary sinuses of every patient were bilaterally measured in three planes. Three diameters were obtained: maximum transverse (horizontal) diameter called MSW, maximum vertical diameter called MSH, and maximum anteroposterior diameter (length) called MSL. In females, the correlation of MSW, MSH, and MSL and zy-zy, as well as n-pr distances, is very strong. Moreover, the significant correlation was found between all measurements of maxillary sinus and ns-pr as well as ns-P distances in females. The correlation between MSL and all measurements of midface as well as MSH and MSW and all measurements except ns-P is stronger in females than in males. In males, all measurements of maxillary sinus correlate with ns-P distance very strongly. Conclusions. The statistical analysis (correlation and determination coefficient) showed that all measurements of maxillary sinuses correlate with midface dimensions.
Maxillary Sinus Augmentation with Decellularized Bovine Compact Particles: A Radiological, Clinical, and Histologic Report of 4 Cases
Background. One of the most problematic regions for endosseous implants is the posterior maxilla, not only having poor bone density, but also lacking adequate vertical height as a result of sinus pneumatization. The purpose of the present study was a radiologic, histological, and histomorphometrical evaluation, in humans, of specimens retrieved from sinuses augmented with decellularized bovine compact particles, after a healing period of 6 months. Methods. Four patients, with atrophic resorbed maxillas, underwent a sinus lift augmentation with decellularized bovine compact bone from bovine femur. The size of the particles used was 0.25–1 mm. A total of four grafts and 5 biopsies were retrieved and processed to obtain thin ground sections with the Precise 1 Automated System. Results. The mean volume after graft elevation calculated for each of the 4 patients was 2106 mm3 in the immediate postoperative period (5–7 days), ranging from 1408.8 to 2946.4 mm3. In the late postoperative period (6 months) it was 2053 mm3, ranging from 1339.9 to 2808.9 mm3. Histomorphometry showed that newly formed bone was 36±1.6% and marrow spaces were 34±1.6%, while the residual graft material was 35±1.4%. Conclusion. In conclusion, based on the outcome of the present study, Re-Bone® can be used with success in sinus augmentation procedures and 6 months are considered an adequate time for maturation before implant placement.
BM-MSCs and Bio-Oss complexes enhanced new bone formation during maxillary sinus floor augmentation by promoting differentiation of BM-MSCs
Bone marrow-derived mesenchymal stem cells (BM-MSCs) have been recognized as a new strategy for maxillary sinus floor elevation. However, little is known concerning the effect of the biomechanical pressure (i.e., sinus pressure, masticatory pressure, and respiration) on the differentiation of BM-MSCs and the formation of new bone during maxillary sinus floor elevation. The differentiation of BM-MSCs into osteoblasts was examined in vitro under cyclic compressive pressure using the Flexcell® pressure system, and by immunohistochemical analysis, qRT-PCR, and Western blot. Micro-CT was used to detect bone formation and allow image reconstruction of the entire maxillary sinus floor elevation area. Differentiation of BM-MSCs into osteoblasts was significantly increased under cyclic compressive pressure. The formation of new bone was enhanced after implantation of the pressured complex of BM-MSCs and Bio-Oss during maxillary sinus floor elevation. The pressured complex of BM-MSCs and Bio-Oss promoted new bone formation and maturation in the rabbit maxillary sinus. Stem cell therapy combined with this tissue engineering technique could be effectively used in maxillary sinus elevation and bone regeneration.
Pneumosinus dilatans, pneumocoele or air cyst? A case report and literature review
Pathological paranasal sinus expansion secondary to air is uncommon. However, this condition may be symptomatic or cosmetically apparent, requiring surgical intervention. Various terms have been used to describe this condition, and nomenclature is controversial. An 18-year-old man presented with right facial pain, and was subsequently found to have pneumosinus dilatans of the maxillary sinus. A search was conducted of the PubMed, Medline and Embase databases, using the key words 'pneumosinus dilatans', 'pneumoc(o)ele', 'pneumatoc(o)ele' and 'maxillary sinus'. Articles were also hand-searched. Relevant articles published in English were reviewed. The literature review identified 36 cases involving the maxillary sinus (including the present case), with 19 cases reported as pneumosinus dilatans, 12 as pneumocoeles, two as pneumatocoeles, two as pneumosinus dilatans multiplex and one as an air cyst. However, based on the strict classification described by Urken et al., the majority of these cases should be reclassified as pneumocoeles. Whilst the nomenclature of this pathology is confusing, distinctions of terminology do not alter the management. Hence, we support the use of the term 'air cyst', to incorporate all these lesions.
Growth Pattern of the Maxillary Sinus in the Miniature Pig (Sus scrofa)
The biological role of the paranasal sinuses is obscure, can be elucidated through a cross-sectional growth study of the maxillary sinus in miniature pigs. The maxillary sinus area was obtained from lateral cephalograms of left skull halves of 103 female miniature pigs of known ages, from newborn to 24 months. Out of several nonlinear models, the growth of the maxillary sinus was best described with the Gompertz model. The first derivative of the Gompertz curve revealed an increase in the growth rates of the maxillary sinus until 4 months, after which sinus growth slowed down. The eruption of the permanent molars did not seem to have a significant influence on this growth pattern. Furthermore, growth in maxillary sinus size in the miniature pig does not follow growth in skull size closely, which showed the highest growth rates in newborn animals. In addition, a correlation analysis revealed that the relationship between maxillary sinus area and different characteristics of the masticatory apparatus (including linear cranial dimensions, and the dry weight of the masseter and zygomatico-mandibularis muscles) were influenced greatly by skull size. These results suggest that the existence of pneumatic cavities within the mammalian skull is not satisfactorily explained solely by an architectural theory. Epigenetic factors are likely to influence the final shape of the maxillary sinus.
A CT Study of the Course of Growth of the Maxillary Sinus: Normal Subjects and Subjects with Chronic Sinusitis
We measured the maxillary sinus volume of normal children and those with bilateral chronic sinusitis by coronal CT scan of the paranasal sinus, and compared the results with findings previously obtained from adult patients. The distribution of mean maxillary sinus volume by age group from 4–9 to 70–79 years exhibited a monomodal pattern with a peak in the 20s in both the normal group and the surgical therapy group. The maxillary sinus volumes of children aged 10–15 years and adults tended to be smaller in the surgical therapy group than in the normal group; this tendency was more prominent in the adult group. These findings appear to support the hypothesis that the ethmoid infundibulum and middle meatus are narrowed by inflammation of the ostiomeatal complex and by various bony anatomic variations in the nasal cavity, leading to impaired pneumatization of the maxillary sinus.
A Longitudinal Study of the Growth Pattern of the Maxillary Sinus in the Pig-Tailed Macaque (Macaca nemestrina)
The ontogeny of sexual dimorphism in maxillary sinus size in a nonhuman primate was studied longitudinally for a period of 8 years in 25 female and 25 male Macaca nemestrina via lateral cephalograms. The maxillary sinus was traced and its area digitized. The growth of female maxillary sinuses was described with a Gompertz model; the best fit to the male data was obtained by the logistic model. Growth curves and confidence intervals revealed that the sinuses grew in a similar fashion for 3–4 years in both sexes. After this, female sinuses achieved a plateau in their development while male sinuses continued to grow. Confidence intervals suggested that size dimorphism appeared at the age of 6.3 years. Lowess regression indicated growth spurts in both sexes. Females experienced an earlier and smaller spurt than males. Sexual dimorphism in maxillary sinus size seems to represent a combination of differences in velocity and length of growth. This study indicates that growth of the maxillary sinus follows closely the growth in body size. Nevertheless, due to the variation in sinus size in Macaca, it is questionable if body size is the main determinant of maxillary sinus size. It is suggested that Macaca, with its wide geographic range and different environments, is an especially appropriate genus to use to test hypotheses about the evolution of skull pneumatization in primates.