拔牙窝内植入不同深度骨水平种植体周围软硬组织改建的组织形态变化

目的 比较新鲜拔牙窝内植入不同深度种植体后软、硬组织的变化。方法 6只成年拉布拉多犬的双侧前磨牙拔除后,立即将24颗种植体以不同深度植入拔牙窝内。将Straumann^®骨水平种植体按以下不同深度植入拔牙窝—颊侧牙槽嵴下2 mm,颊侧牙槽嵴下1 mm,与牙槽嵴齐平,以及颊侧牙槽嵴上方1 mm。愈合6个月后采集样本,获得未脱钙切片,进行组织学观察、测量,获得垂直骨吸收和生物学宽度。采用SPSS 19.0软件包对数据进行统计学分析。结果 所有种植体均获得成功骨结合。骨吸收以种植体植入牙槽嵴下2 mm处最显著（P<0.05）。以不同深度植入时,生物学宽度无显著差别。结论 在新鲜拔牙窝内植入种植体时,不同植入深度对骨吸收有影响。当植入深度为骨下2 mm时,骨吸收最多。     

牙种植体即刻种植骨愈合过程的组织学观察

目的：了解即刻种植体的骨愈合过程，验证即刻种植的可行性。方法：在１２只犬下颌前磨牙新鲜拔牙创内立即植入纯钛牙种植体，通过组织学光镜和扫描电镜观察术后２、４、６、８、１２周种植体周围骨缺损修复过程和种植体骨结合形成情况。结果：骨缺损区内血块首先机化，而后沿牙槽窝骨壁向中心方向逐渐骨化形成新骨。小于１ｍｍ骨缺损１２周内可完全修复，种植体骨结合形成；１ｍｍ以上骨缺损则不能完全修复。结论：即刻种植体周围骨缺损的修复和骨结合形成类似于拔牙创的愈合，大于１ｍｍ的骨缺损应争取植骨。     

拔牙创即刻植入牙种植体 HA颗粒36例临床观察

目的　为有效地防止牙槽骨吸收 ,减少手术次数 ,缩短无牙期。方法　在拔除患牙同时修整拔牙窝 ,植入牙种植体及 HA颗粒。结果　对 36例 41个牙种植体经 3年临床观察 ,成功率为 97.5 % ,与 32个延期牙种植体比较无显著性差别。结论　拔牙后即刻植入牙种植体的同时植入 HA颗粒 ,有助于牙种植体的初步稳定和骨愈合 ,同时可以达到与延期种植同样效果。     

种植相关的牙槽嵴保存技术

充足的牙槽骨宽高度和骨质量是种植体植入的前提条件。但拔牙后局部牙槽骨的改建和吸收极易造成骨量和骨质减少,影响种植体植入。牙槽嵴保存技术有利于拔牙后牙槽骨的愈合,减少骨吸收,为后期种植修复创造条件。本文将对近年来牙槽嵴保存的方法、疗效及后期种植体植入效果做一综述。     

Straumann骨水平种植体即刻种植：病例报道

骨内牙种植体已成为临床医师治疗无牙颌和部分无牙颌患者的革命性的方法。传统的种植方法明确规定了拔牙后需要几个月的愈合期，以及在进行最终修复之前需要无负荷愈合期。在过去的10年中．许多研究已经证实在新鲜拔牙区即刻植入种植体，并且进行早期的功能负荷可以促进植入体成功愈合。本研究目的是介绍牙种植体即刻植入和早期负重的临床治疗方案．并且报告在上颌骨或下颌骨新鲜拔牙区植入Straumann亲水性表面种植体的临床和影像学效果。     

拔牙位点保存

目的：探讨拔牙位点保存在种植体植入之前保存拔牙后的牙槽嵴和软组织、预防拔牙后的牙槽嵴吸收,并改善骨和软组织质量的效果。方法：29例前牙和前磨牙单颗牙位点,拔牙后即刻向拔牙窝内植入去蛋白牛骨基质,游离移植腭粘膜瓣覆盖并初期创口关闭。6个月之后植入种植体,4个月之后修复。测量骨的颊舌向厚度和高度变化,以及龈乳头的高度变化。结果：牙槽窝粘膜及骨愈合良好,成功完成最终种植修复。结论：位点保存技术可以成功实现拔牙窝骨愈合,减少因拔牙造成的骨缺损,有利于提高种植的成功率,降低GBR的必要性。     

骨移植牙种植体同期植入的扫描电镜观察

目的：探讨骨移植牙种植体同期植入后骨整合的效果。方法：恒河猴6只随机分三组分别行血管吻合骨移植（Vascularized Bone Graft,VBG)牙种植体同期植入；游离骨移植（Non-Vascularized Bone Graft,NVBG)牙种植体同期植入，拔牙后三个月植入牙种植体，切取标本后扫描电镜观察，结果：VBG组：术后12周移植骨与种植体之间部分为骨性结合界面，16周呈完整的骨性结合，NVBG组：术后12周其界面为纤维结缔组织，少量骨少梁，24周大部分为骨性结合界面，呈完整的骨性结合。结论：VBG或NVBG牙种植体同期植入均能形成骨性整合，但NVBG组形成较晚，临床应用中应予注意。     

拔牙窝位点保存的初步临床观察

目的:观察拔牙同期行拔牙窝植入Bio-ossCollagen位点保存,延期种植体植入的临床疗效。方法:对14例要求拔牙后作牙种植修复的病例,拔牙后牙槽窝内植入Bio-ossCollagen进行位点保存,术后观察软硬组织愈合情况,4-6个月后,在植骨位置行临床和X线检查,确定足够的牙槽骨骨量,行种植体植入术。结果:14例患者植骨区愈合良好,外形丰满,高度和宽度基本保持,顺利完成种植修复。结论:拔牙后牙槽窝即刻植骨位点保存,可有效保持牙槽骨外形,提供足够的牙槽骨高度和宽度。在足够骨量基础上行延期种植近期临床效果满意,长期效果尚需进一步观察。     

牙种植体即刻种植的有关技术问题的处理--附16例观察报告

目的：探讨即刻牙种植过程中有关技术问题的处理方法。方法：对16例患者拔牙后即刻植入Frialit-2种植体21枚，术后定期进行X线片检查种植体骨的结合和牙槽骨变化情况。结果：24个月后2-枚种植体成功，种植体与骨组织结合稳固，19枚未见骨缺损，2枚欠佳。结论：选择合适的Frialit-2种植体、应用骨劈开技术、骨挤压技术和骨组织引导再生(GBR)技术及严密关闭创口是即刻牙种植获得成功的有效方法。     

牙周病患者拔牙后即刻植入骨粉一例报道

目的:报道一例牙周病患者拔牙后即刻植入骨粉的成骨情况及种植修复后效果.方法:患者男性,71岁,下颌余留牙为43.43牙槽骨吸收2/3,Ⅱ度松动,拟拔除43后,刮净肉芽组织,即刻行骨粉植入,择期与33,43位置植入种植体,行覆盖义齿修复.结果:四月后,临床检查34部位牙槽窝愈合情况良好,有部分骨粉未吸收,X线示43牙槽窝底,中1/3骨质密度高,五月后43,33种植体植入,修复后效果良好.讨论:该病例患牙拔除后即刻植入骨粉虽未完全成骨,但对于种植体骨结合和修复后效果未有明显影响.结论:牙周病患者拔牙后若缺骨严重可考虑即刻行骨粉植入,以缩短种植修复时间.     

匹配牙槽窝的根形种植体即刻种植的动物实验研究

目的 探讨更加完善成熟的即刻种植技术和方法。 方法 选用当地生产杂种犬9只,采用自身对照方式,拔除所有动物下颌双侧第三、四前磨牙,每个前磨牙均为2个根即近中根与远中根,在右侧第三、四前磨牙远中根拔牙窝、左侧第三、四前磨牙近中根拔牙窝,直接植入直径与拔牙窝相匹配的种植体为Sim组;在左侧第三、四前磨牙远中根拔牙窝,采用直径小于拔牙窝的种植体和Bio-oss骨粉联合植入为Bio组。分别于术后1个月、2个月、3个月随机处死3只实验动物,制成HE染色组织切片,做光镜及骨组织形态计量学观察。 结果 Sim组种植体成功率高。光镜观察Sim组骨板连续性较好、较厚、周围有大量成骨细胞。骨组织形态计量学观察：Sim组在1个月时的骨性结合率（CLF）、界面新骨生长率(BIF)均大于Bio组,两组之间有显著的统计学差异﹙P＜0.05﹚,Sim组在2个月、3个月时的骨性结合率,界面新骨生长率均稍大于Bio组,两组之间无显著的统计学差异(P＞0.05)。 结论 直接植入与牙槽窝相匹配的根形种植体可加速种植体的骨性结合,其骨结合率高于种植体周围骨缺损充填Bio-oss骨粉。     

Differences between the bony interfaces of titanium and hydroxyapatite-alumina plasma-sprayed titanium blade implants

Histopathologic study was done to reveal the difference of bony interface in the mandibular bone between titanium blade implants and titanium implants coated with the mixture of hydroxyapatite-alumina by the plasma-spray technique, using the improved undecalcified histologic technique and the image analyzing system. In 4 adult shepherd dogs, the implantation was performed in the molar region of the mandible 2 months after tooth extraction. The coated implants and the non-coated ones were inserted respectively in the mandibles. They were sacrificed on the 5th, 7th, 14th and 28th day postoperatively. In 5-day implant after insertion, granulation tissues or fibrous connective tissues were observed around both implants in bone tissues. In 7-day implant, osteoid tissues regenerated around the apex of both implants, but attached a little to them. In 14-day implant, osteoid tissues or woven bone regenerated around both implants and attached more to the coated implant (approximately 13.7%) than the non-coated one (approximately 6.0%). In 28-day implant, regenerative woven or lamellar bone attached much more to the coated implant (approximately 63.4%) than the non-coated one (approximately 8.8%). Bony interface increased remarkably in the coated implants, chronologically. The results showed that the plasma-sprayed hydroxyapatite-alumina coating was effective for the initial fixation of endosseous dental implants.     

Vertical distraction of the severely resorbed mandible. The Groningen distraction device

In this paper, both the surgical procedure and the clinical results of a novel distraction device to augment a severely resorbed anterior edentulous mandible are described. The distraction device is non-voluminous, and consists of two distraction screws and one guide screw. Two months after the last day of distraction, both distraction screws are replaced by endosseous implants and the guide screw is removed. Three months after implantation, the prosthetic treatment can be started. So far three patients have been treated. In all patients, the severely resorbed mandible (mandibular height in the canine region: 5, 6 and 7 mm, respectively) could be sufficiently enlarged to enable reliable insertion of endosseous implants with a length of at least 12 mm. No complications occurred. Biopsies taken from the distraction site revealed formation of lamellar bone parallel to the distraction vector. From this preliminary study it is concluded that the Groningen vertical distraction device has the potential for reliable augmentation of the anterior segment of a severely resorbed edentulous mandible to enable insertion of endosseous implants with adequate length and primary stability.     

Healing‐in of root analogue titanium implants placed in extraction sockets. An experimental study in the beagle dog.

The aim of these animal experiments was to characterize and evaluate the healing-in of root analogue titanium implants fitting with high precision to the alveolar wall. Four beagle dogs were used in the study. The roots of the 3rd and 4th mandibular premolars in both quadrants of 3 dogs and in 1 quadrant of 1 dog (dog 4) were extracted after hemisection. Each root was machine-copied to 1 titanium analogue. In dog 4, however, 2 titanium analogues were fabricated from each of the 4 extracted roots. This enabled insertion of analogues also into the contralateral sockets obtained by extraction of the corresponding roots immediately before implant installation, which was undertaken 2 weeks after the first extractions. Thus, in all, 32 analogues were implanted in their respective (or contralateral) sockets following ridge incision and elevation of mucoperiosteal flaps. The analogues were carefully covered by the repositioned flaps. In dog 4, 2 analogues from the immediate sockets and 2 from the 2-week sockets were surgically exposed and supplied with titanium crowns after a healing period of 2 months. The healing after implantation was evaluated by clinical, radiographic and histological measures after 2, 12 or 36 months. Two analogues (6%) were lost due to early (during the 1st week) exposure to the oral cavity. Another 2 analogues (6%) were, although not exposed, encapsulated by soft tissue and were easily removed with a surgical forceps. Twenty-eight analogues (88%) were healed-in by contact between bone and implant (osseointegration). The mean percentages of bone tissue in contact with the implant of such analogues were 30.5% after 2 months, 64.8% after 12 months and 68.1% after 36 months, as evaluated by histomorphometric analysis. The 4 analogues supplied with titanium crowns carried those with maintained bone anchorage throughout an experimental period of 36 months. The character of the interface between the analogue and the surrounding bone tissue was the same regardless of whether the implantation was performed immediately 1 or 2 weeks after extraction of the roots.     

Vertical distraction of the severely resorbed edentulous mandible: a clinical,histological and electron microscopic study of 10 treated cases

The aim of this study was to evaluate the clinical and histomorphological results of distraction of the severely resorbed edentulous mandible. In a group of 10 edentulous patients suffering from insufficient retention of their mandibular denture related to a severely resorbed mandible, the anterior segment was augmented as a preimplant surgical procedure using the nonvoluminous Groningen Distraction Device (GDD). Two months after the last day of distraction, a bone biopsy was taken with a trephine, both distraction screws were replaced by endosseous implants and the guide screw was removed. The biopsies were examined by means of light microscopy (LM) and transmission electron microscopy (TEM). Radiographical and histomorphological examination of the biopsies revealed the presence of two cortical zones, one at each end of the biopsies, a poorly mineralized, fibrous interzone in the middle of the distraction gap, and two zones of mineralization between the central fibrous and the peripheral cortical zones. Formation of lamellar bone parallel to the distraction vector was clearly visible in the mineralization zone as well as signs of remodelling at the borderline between the native cortical bone and the generate. Clinical examination showed in all patients that the anterior segment distracted from the mandible body was sufficiently enlarged to enable insertion of endosseous implants with a length of at least 12 mm. One implant was lost during the healing phase, but was successfully replaced thereafter. Implant retained overdentures were fabricated 3 months after implantation. All patients have good function 11.2 +/- 4.3 months after the end of treatment. From this study it is concluded that the GDD has proven to be a reliable tool for augmentation of the anterior segment of a severely resorbed edentulous mandible enabling osseointegration of endosseous load-bearing implants.     

Histomorphometric and removal torque analysis for TiO2-blasted titanium implants. An experimental study on dogs

The aim of the present study was to compare the anchorage of TiO2-blasted screw and cylindrical implants with conventionally used machine-produced screw and cylindrical implants inserted immediately in extraction sockets on dogs. 6 adult mongrel dogs had 3rd and 4th mandibular premolars extracted bilaterally and 24 commercial pure titanium implants were placed immediately in extraction sockets and covered with mucoperiosteum. Each dog had inserted 4 implants: 1 screw implant and 1 cylindrical implant blasted with titanium-dioxide-particles; 1 screw implant and 1 cylindrical implant with machine-produced (m.p.) surface (controls). After a healing period of 12 weeks, 16 implants from 4 animals were used for removal torque test, which demonstrated that significantly higher removal torque force was needed to unscrew the implants blasted with titanium-dioxide-particles, than the normal m.p. implants. The medians for the TiO2-blasted screw and cylindrical implants were > 150 Ncm and 105 Ncm, respectively, while the values for the m.p. implants were 60 Ncm and 35 Ncm, respectively. The SEM investigation demonstrated a high irregularity of the TiO2-blasted surface compared to the machined surface. The Ra and Rz values for surface roughness were higher for the TiO2-blasted implants than for the normal m.p. implants. Histomorphometrically, the arithmetic mean of the direct bone-implant contact fraction was 69%. There was no significant difference in direct bone-implant contact length fraction between TiO2-blasted implants and the control implants. The implants blasted with titanium-dioxide-particles in this study showed a better anchorage than implants with a machine-produced surface. The screw implants showed a better anchorage than the cylindrical implants.     

Healing-in of root analogue titanium implants placed in extraction sockets. An experimental study in the beagle dog.

The aim of these animal experiments was to characterize and evaluate the healing-in of root analogue titanium implants fitting with high precision to the alveolar wall. Four beagle dogs were used in the study. The roots of the 3rd and 4th mandibular premolars in both quadrants of 3 dogs and in 1 quadrant of 1 dog (dog 4) were extracted after hemisection. Each root was machine-copied to 1 titanium analogue. In dog 4, however, 2 titanium analogues were fabricated from each of the 4 extracted roots. This enabled insertion of analogues also into the contralateral sockets obtained by extraction of the corresponding roots immediately before implant installation, which was undertaken 2 weeks after the first extractions. Thus, in all, 32 analogues were implanted in their respective (or contralateral) sockets following ridge incision and elevation of mucoperiosteal flaps. The analogues were carefully covered by the repositioned flaps. In dog 4, 2 analogues from the immediate sockets and 2 from the 2-week sockets were surgically exposed and supplied with titanium crowns after a healing period of 2 months. The healing after implantation was evaluated by clinical, radiographic and histological measures after 2, 12 or 36 months. Two analogues (6%) were lost due to early (during the 1st week) exposure to the oral cavity. Another 2 analogues (6%) were, although not exposed, encapsulated by soft tissue and were easily removed with a surgical forceps. Twenty-eight analogues (88%) were healed-in by contact between bone and implant (osseointegration).(ABSTRACT TRUNCATED AT 250 WORDS)     

Guided tissue regeneration ensures osseointegration of dental implants placed into extraction sockets. An experimental study in monkeys.

The aim of the present study was to explore the possibility of achieving osseointegration of dental titanium implants, inserted into alveoli immediately after tooth extraction, by covering the recipient site with a teflon membrane. In each of 7 monkeys, mucoperiosteal flaps were raised on the buccal and palatal aspects of the maxillary molars in both sides of the jaw. The second molars were then extracted and self tapping titanium implants of the screw type (Astra® Dental Implants) were inserted into the sockets of the largest roots. In the coronal portion of the sockets, a void was always present between the implant and the socket walls. In one side of the jaw, a membrane (Gore‐;Tex Aug‐mentation Material@) was adjusted to cover the implant. The implant in the other side of the jaw served as control and was only covered by the tissue flaps. Microscopic analysis after 3 months of healing revealed that soft tissue was facing the coronal portion of the implants to a varying degree in the control side, while osseointegration was consistently observed to the top of the membrane‐covered implants which remained submerged throughout the experimental period. The results suggest that the membrane techniaue can secure complete osseointegration of implants inserted immediately into extraction sockets.     

Comparative study of hydroxyapatite and titanium dental implants in dogs

This study compares the clinical performances and histologic response in dogs to a cylindrical implant with a surface consisting of dense hydroxyapatite (HA) and a threaded titanium implant in functionally loaded and unloaded conditions. Implantation was performed in five dogs, which were killed at 2 or 4 months postfunctional condition (4 or 6 months after implantation). Clinical evaluation showed that neither implant demonstrated significant movement, and assessment of gingival inflammation and sulcus depth showed no significant differences between them. After axial sectioning, the titanium implants were easily removed from the bone, whereas the HA-coated implants were adherent to the bone. Histologically, both implants showed osteogenic ingrowth to the surface in functional and nonfunctional conditions. High-magnification scanning electron micrographs of plastic sections showed that a portion of the interface between the HA-coated implant and the bone showed no gap, whereas gaps were observed at all interfaces with the titanium implant. Histomorphometric analysis by light microscopy indicated that there was no significant difference in the percent bone contact length. Clinically, the two implants behaved similarly.     

种植体周骨缺损时羟基磷灰石颗粒植入的实验研究

目的为研究羟基磷灰石颗粒在即刻人工种植体的愈合过程中的作用。方法作者应用国产ＨＡ层钛种植体植入犬股骨中进行观察，术后１、２、３、４个月处死动物，通过Ｘ线检查及扫描电镜观察标本。结果即刻种植组中，用ＨＡ充填空隙后，其愈合情况在术后３个月与延期种植无明显差异，种植体和骨组织结合紧密；无ＨＡ充填的标本中与延期种植存在差异，４个月时颈部尚有部分骨组织缺损。结论即刻种植术中，在植入种植体的同时植入ＨＡ颗粒。有助于种植体的稳定，对种植体与周围骨组织早期愈合起到较大作用。