Human prenatal palatal shelf elevation related to craniofacial skeletal maturation.

Much attention has been focused on the mechanisms responsible for the elevation and fusion of the palatal processes during formation of the secondary palate. In a former publication this closure, defined as fusion of the palatal shelves along their length, was described as occurring at a period in osseous palatal development characterized by incipient ossification of the maxillae and palatine bones, and at a stage in early mandibular development when the mandibular condyle has not developed. The purpose of the present study was to examine the osseous maturation of the cranial base at the time of palatal closure. The investigation was based on 62 human embryos and fetuses, CRL 22-57 mm, and general skeletal hand and foot maturation CNO = 0-0 to CNO = 8-1 (CNO, Composite Number of Ossified bones in hand and foot). From the fetuses, cranial tissue was dissected out and skeletal maturity was determined radiographically according to formerly described skeletal maturity stages in the cranial base. The study revealed that the soft tissue palatal shelves always elevate and fuse along their length at a specific, well-defined stage of maturity in the cranial base. The cranial base development in this stage is characterized by unossified cartilage. This information is essential for understanding abnormal skeletal development of the oral and nasal cavities.     

Chromosomal aberrations in adenomatoid hyperplasia of palatal minor salivary gland

Adenomatoid hyperplasia of minor salivary glands is rare, idiopathic, and benign, and typically presents as a tumour-like mass in the hard or soft palate. Its exact nature is not clear and histological examination usually shows an excess of normal-appearing minor salivary glands. To our knowledge, cytogenetic analysis of it in a minor salivary gland of the palate has not previously been reported. We present the cytogenetic analysis of adenomatoid hyperplasia in the hard palate of a 52-year-old woman.     

腭部不同微种植体植入位置的骨质情况研究

目的:研究腭部骨质情况,提供腭部微种植植入参考图。方法:硬腭部测量时,纳入148例研究对象;腭侧牙槽骨测量时,筛选出其中的86名研究对象,使用CBCT分别测量其骨质情况。结果:硬腭部的骨质厚度在前磨牙间冠状面处最大;腭侧牙根间间距随着远离牙槽嵴顶而逐渐增加。结论:硬腭部微种植体植入部位推荐在前磨牙间冠状面植入。腭侧牙槽骨前牙区推荐在侧切牙与尖牙间距离牙槽嵴顶6 mm以上水平植入;前磨牙区推荐在距离牙槽嵴顶4 mm以上水平植入;磨牙区推荐斜形植入,高于牙槽嵴顶8 mm时需注意上颌窦的影响。     

正常(牙合)成年人硬腭部骨质厚度初探

目的 测量正常(牙合)成年人硬腭部骨质厚度,以期为腭部支抗种植体的安全植入提供基础数据.方法 选择32名正常(牙合)、无正畸治疗史的成年人(男性16人,女性16人),年龄(30.1±6.5)岁.拍摄锥体束CT(cone beam computerized tomography,CBCT),以经过切牙孔后缘的冠状线为基线,向后与(牙合)平面垂直、与基线平行、在正中矢状线上每隔3 mm对硬腭部进行重建,选取7个与(牙合)平面垂直的冠状面,第1层为切牙孔后缘冠状面,第7层为距离切牙孔后缘18 mm的冠状面.在每个冠状面上确定位于正中矢状线上的腭中缝点为M点,左右侧硬腭水平部最外缘点为D点,均分M点与D点连线为4等份,从内到外依次命名为A、B、C点.测量各点对应处硬腭部骨质厚度.结果 硬腭部第1～7层骨质厚度的差异有统计学意义,骨质厚度从前向后逐渐递减;最厚处为12.6 mm,位于第1层冠状面D点;最薄处为2.7 mm,位于第7层冠状面B点;第2、3层冠状面骨质厚度最高为10.5 mm,最低为5.8 mm.硬腭部左右两侧骨质厚度差异均无统计学意义(P＞0.05).结论 正常(牙合)成年人硬腭部距切牙孔后缘6 mm内可植入长度为5～10 mm的支抗种植体.

Abstract：

Objective To investigate the palatal bone thickness in adult with normal occlusion Methods The cone beam computerized tomography records of 32 adults with normal occlusion ( 16 males and 16 females), mean age (30. 1 ±6. 5) years, were used to measure the bone thickness at midpalatal area and the right and left palatal sides. Coronal slices at 3 mm intervals were generated. Slice 1 was the coronal slice through the posterior border to the incisive foramen, while Slice 7 was the coronal slice 18 mm away from the incisive foramen. At each coronal slice, the midpalatal sites were Site M and the sites on the exterior margin of the hard palatal were Site D. Four equally divided parts on the line linking Site M to Site D were named Site A, B, C from the interior to the exterior respectively. Palatal bone thickness were measured at these sites. Results Significant differences were noted from Slice 1 to Slice 7, the bone thickness of palate tended to decrease from the front to the back. The thickest site at hard palatal was 12. 6 mm, locating at Site D of Slice 1, while the thinnest site was 2. 7 mm, locating at Site B of Slice 7.The palatal bone thickness ranged from 10. 5 mm(maximum) to 5. 8 mm(minimum) at Slice 2 and Slice 3. No statistical significance was found between the left and right sides ( P ＞ 0. 05 ). Conclusions The favorable sites for miniscrew placement were the anterior region of the hard palate in adult. The length of miniscrew ranged from 5 mm to 10 mm can be placed from 6 mm posterior to the incisive foramen.     

18三体及正常NMRI小鼠腭皱发育的形态学研究

目的 通过对18三体伴及不伴腭裂NMRI胚鼠和正常胚鼠的腭皱形态的比较形态学观察研究,认识其腭皱发育的不同特点。方法 60只Han-NMRI母鼠及11只具有Rb(2.18)6Rma/Rb(1.18)Rma染色体结构的雄鼠被用于该研究,从569只子代活胚中选择82只整倍体鼠胚,17只18三体不伴腭裂鼠胚和32只18三体伴腭裂鼠胚,对其腭皱形态进行形态学观察和分类。结果 非腭裂小鼠腭皱有四种不同的表现型,整倍体小鼠腭皱表型以I类为主,18三体小鼠腭皱则以IV类多见,18三体伴腭裂小鼠腭皱有两种不同类型,其中以I类多见,结论 18三体小鼠的过量基因不仅可导致其子代腭裂发生率的增高,也使其腭皱发育呈现明显的不连续及个别缺失畸形,18三体不伴腭裂小鼠的腭皱发育与正常NMRI小鼠有明显区别。     

维甲酸对口腔黏膜上皮细胞增殖的影响

目的探讨不同浓度维甲酸对体外培养的口腔黏膜上皮增殖的影响。方法将第二代人口腔黏膜上皮细胞以4×104个/cm2接种于玻片上,在含钙1.2 mmol/L的无血清角朊细胞培养基中培养,将其按培养基中的维甲酸浓度分为0、10-8、10-7、10-6、2×10-6mmol/L共5组。对各组细胞进行硝酸银染色,观察核仁区相关嗜银蛋白(AgNOR s)的着色情况,并对细胞核AgNOR s面积进行图像分析,以评价维甲酸对口腔上皮细胞增殖能力的影响。结果高钙培养基中维甲酸浓度为10-7~10-6mmol/L时,体外培养的上皮细胞内AgNOR s面积与维甲酸浓度0、10-8mmol/L 2个实验组有显著差异(P<0.01)。结论维甲酸可有效地拮抗因钙离子诱导上皮细胞分化所致增殖抑制。     

锥形束CT测量不同矢状骨面型青少年腭部骨厚度

目的：研究锥形束CT（CBCT）测量青少年患者腭部不同区域骨厚度的差异,分析在腭部相同区域中Ⅰ、Ⅱ、Ⅲ类矢状骨面型青少年患者骨厚度的差异,为临床腭种植支抗的植入提供参考。方法选取90例垂直骨面型为均角的12～16岁青少年患者,依照矢状骨面型分为Ⅰ、Ⅱ、Ⅲ类三组,每组男女各15例,进行CBCT扫描。以切牙孔后缘与后鼻棘点连线作为水平基准平面,在切牙孔后4.0、8.0、12.0、16.0、20.0、24.0 mm冠状向截面上,距腭中线0.0、2.0、4.0、6.0 mm矢状向截面上,测量两基准线的24个交点的垂直骨厚度。结果（1）腭部骨厚度在腭中缝处由前往后逐渐增加,在腭侧区及腭旁区由前往后逐渐减少（P＜0.05）;（2）腭部骨厚度在前份区域从腭中缝往两侧逐渐增加,在中份及后份区域由腭中缝往两侧逐渐减少（P＜0.05）;（3）在腭部的相同区域中,不同矢状骨面型青少年患者腭部骨厚度差异有统计学意义（P＜0.05）。在腭中缝前份、腭中缝中份、腭中缝后份、腭侧区前份、腭旁区前份区域中,Ⅰ、Ⅱ类青少年患者腭部骨厚度大于Ⅲ类青少年患者;腭侧区中份、腭侧区后份、腭旁区中份、腭旁区后份区域中,仅Ⅱ类青少年患者腭部骨厚度大于Ⅲ类青少年患者。结论（1）腭部微种植支抗的最佳植入部位为腭旁区前份;（2）在相同腭部植入区域中,Ⅲ类青少年患者骨厚度小,穿通鼻底风险更大,建议Ⅲ类青少年患者选择更短的腭种植支抗。     

Epithelial-mesenchymal interaction in palatal shelf fusion.: An in vitro study

A bstract — Cleft palate is the result of a number of deviations from normal facial development, including failure of the paired palatal shelves to fuse in the midline. By the use of in vitro techniques it is possible to isolate and study fusion alone. This study investigates some of the epithelial-mesenchymal interactions involved and finds that contact between two epithelial covered surfaces is essential for fusion.     

应用锥形束CT评估腭部种植体的植入部位

目的 对腭部种植体支抗植入部位的骨厚度和骨密度进行定量研究,为临床安全、稳定地植入腭部种植体提供参考依据.方法 测量34例正畸患者(18～35岁)腭部20个兴趣区的骨厚度、种植体可植入率高的10个部位的骨密度,将34例患者的头颅锥形束CT扫描数据导入EZ种植分析软件获得三维重建图像,以骨厚度、骨密度为指标的数据进行K均值聚类分析.结果 将可植入率高的10个部位分为3类(Ⅰ～Ⅲ类),骨厚度:Ⅱ类(8.3±0.4 mm)>Ⅰ类(6.2±0.5 mm)、Ⅲ类(5.4±0.4 mm);骨密度:Ⅲ类(638.6±42.5 HU)>Ⅰ类(514.6±63.6 HU)>Ⅱ类(414.8±11.1 HU):3类骨厚度、骨密度比较,差异有统计学意义(P<0.05).结论 应用锥形束CT评估腭部种植体支抗的植入部位,在一定程度上有助于种植体安全、稳定.     

替牙期儿童腭部形态的分析研究

目的：通过测量替牙期正常殆儿童的腭部标志点,来评价其腭部形态。方法：通过普查获得87例替牙期正常殆儿童的牙齿模型（男41例,女46例）,用3DSS-Ⅱ彩色结构光扫描系统扫描入电脑进行测量,利用方差分析比较各年龄组问的腭部形态差异。结果：矢状面和水平面上,腭部各测量值的变化均无统计学意义。冠状面上,最大腭高度和腭指数均随年龄增加而增大了,差异有统计学意义（P〈0．05）。结论：在替牙期,随着年龄的增加,腭穹窿的前部变化不是很明显,腭穹窿的后部变得更加高拱,这可能与前牙区和后牙区牙槽嵴的生长速度不一致有关。     

Dynamics and risk indicators of intrasinus elevation height following transalveolar sinus floor elevation with immediate implant placement: a longitudinal cohort study

Successful intrasinus graft consolidation is essential for the treatment outcome of transalveolar sinus floor elevation (SFE). This study was performed to examine the dynamics and risk indicators related to the elevation height after transalveolar SFE with grafting material and simultaneous implant placement. Fifty-two patients with 55 sites undergoing transalveolar SFE with immediate implant placement were enrolled retrospectively. Cone beam computed tomography (CBCT) images were collected and saved in DICOM format, at the following time-points: pre-surgery (T0), immediately post-surgery (T1), and 6 months post-surgery (T2). Voxel-based CBCT superimposition was performed to measure the sinus width, residual alveolar height, implant protrusion length, total elevation height, and apical graft height. The change in total elevation height from T1 to T2 was defined as the study outcome. Clinical and linear variables were analysed using linear regression. From T1 to T2, the total elevation height showed an average reduction of 1.0 ± 1.1 mm, while 10.9% sites showed an increased elevation height. Univariate regression analysis showed no significant correlation between tested clinical or linear variables and the study outcome. The results suggest that the change in elevation height was not influenced by the alveolar or sinus dimensions, graft materials, implant diameter, implant protrusion length, or the total elevation height at T1.     

Epithelial cell kinetics of rat palatal mucosa in organ culture.

The dynamic behaviour of the epithelial cells was evaluated in explants of rat palatal mucosa maintained in a chemically-defined medium in organ culture for periods up to 28 days. Epithelial mitotic activity, comparable with that in vivo, was observed after 5 h in vitro but after 24 h had increased to 4 times the initial value. This increased activity persisted for 4 days and then gradually declined until at 10 days levels comparable with that at the start of the experiment were reached. During the initial period in culture, the thickness of the nucleated cell layer of the epithelium increased slowly, reaching a maximum after 4 days, and then decreased to the initial values by 12 days. The number of nucleated cells per square millimetre of surface also showed a transient increase but such changes did not correspond with changes in thickness. The changes in average cell volume were interpreted as a change in the relative sizes of the different epithelial compartments. It is suggested that the changes are caused by the surgical wounding of the tissues during excision; consequently, rat palatal mucosa maintained in this organ culture system provides a reliable model system for the study of oral mucosa only after a minimum period of 10 days.     

Immunofluorescent detection of actin in non-muscle cells of the developing mouse palatal shelf

Cryostat sections of foetal mouse heads, taken at 14–15 days in utero, were incubated first in serum containing smooth muscle auto-antibody and then in fluorescein-conjugated rabbit or goat IgG directed against human IgG. A positive fluorescent reaction was observed in epithelial and mesenchymal cells of the secondary palate, oral mucosa, nasal septum and tongue. Incubating the auto-antibody-containing serum with highly purified actin blocked the auto-antibody and produced no reaction, suggesting that the contractile protein detected in non-muscle cells of the developing palatal shelf contain the muscle protein, actin.     

Deficient cell proliferation in palatal shelf mesenchyme of CL/Fr mouse embryos

How secondary palate formation is affected in the cleft lip genotype remains poorly understood. The purpose of this study was to analyze regional patterns of cell proliferation in CL/Fr mouse embryos with or without cleft lip. Pairs of palatal shelves were dissected at E13.5 from CL/Fr normal embryos (CL/Fr-N), CL/Fr embryos with bilateral cleft lip (CL/Fr-BCL), and a control strain of C57BL embryos (C57BL). The explants were examined histologically after 48 hrs of organ culture. Cell kinetics for proliferation in the palatal shelves was examined at E13.5 by the bromodeoxyuridine method in vivo. The CL/Fr-BCL palates fused as well as the CL/Fr-N palates in vitro. There were inter-group differences in the absolute number of BrdU-positive cells and the ratio of positive/(positive+negative) cells in the palate's mesenchyme (C57BL > CL/Fr-N > CL/Fr-BCL) and epithelium (C57BL > CL/Fr-N = CL/Fr-BCL). These findings indicate that a cleft palate follows reduced cell proliferation of secondary palatal mesenchyme in CL/Fr mice.     

上颌窦底提升的研究进展

上颌窦底提升是有效解决上颌骨后部骨量不足的方法之一,能为后期种植体的成功植入提供保证。长期以来,利用自体髂骨提升上颌窦底被视为"金标准"。但取髂骨术后,疼痛、感染是其常见并发症。组织工程技术和细胞因子的应用,克服了传统方法的不足,成为上颌窦提升的新进展。本文就此作一综述。     

Epithelial mitotic activity during the induction of palatal candidosis in the Wistar rat

Palatal candidosis was produced in 15 Wistar rats by fitting them with an acrylic appliance that covered the palatal mucosa and simultaneously inoculating this site with Candida albicans 3091 (serotype A). A further 15 rats were fitted with the appliance only. Five animals in each group were killed at 1, 2 and 4 weeks, 4·5h after being injected with vinblastine sulphate, as were 5 normal control animals at the start of the experiment. Palatal mucosa was dissected free, fixed, sectioned and stained prior to counting the number of arrested mitotic figures in the basal epithelial layer and measuring the mean thickness of epithelium. The results were expressed as the number of mitotic figures per 1000 basal cells, per unit length of basement membrane and per square millimetre of epithelial surface. After an initial reduction in thickness, the palatal epithelium in both experimental groups became thicker than that of normal control animals, more markedly so in the animals infected with Candida albicans. Similar patterns of mitotic activity were found regardless of the reference unit used as a basis for the calculations. An initial decrease in both experimental groups was followed by a sharp and significant rise, again being more marked in the animals infected with Candida albicans .     

上颌窦提升术

上颌窦提升术是解决上颌后牙区骨量不足的常用方法。上颌窦提升术可分为上颌窦侧壁开窗术（上颌窦外提升术）和经牙槽嵴入路的上颌窦冲顶提升术（上颌窦内提升术）。本文就上颌窦提升相关解剖、上颌窦提升抗生素选择、上颌窦提升适应证把握、植骨方案选择、促生长因子的作用、上颌窦提升术的常见并发症和吸烟的影响作一论述。     

Epithelial mitotic activity during the induction of palatal candidosis in the Wistar rat

Palatal candidosis was produced in 15 Wistar rats by fitting them with an acrylic appliance that covered the palatal mucosa and simultaneously inoculating this site with Candida albicans 3091 (serotype A). A further 15 rats were fitted with the appliance only. Five animals in each group were killed at 1, 2 and 4 weeks, 4 X 5 h after being injected with vinblastine sulphate, as were 5 normal control animals at the start of the experiment. Palatal mucosa was dissected free, fixed, sectioned and stained prior to counting the number of arrested mitotic figures in the basal epithelial layer and measuring the mean thickness of epithelium. The results were expressed as the number of mitotic figures per 1000 basal cells, per unit length of basement membrane and per square millimetre of epithelial surface. After an initial reduction in thickness, the palatal epithelium in both experimental groups became thicker than that of normal control animals, more markedly so in the animals infected with Candida albicans. Similar patterns of mitotic activity were found regardless of the reference unit used as a basis for the calculations. An initial decrease in both experimental groups was followed by a sharp and significant rise, again being more marked in the animals infected with Candida albicans.