Delgado-Ruiz Rafael Arcesio, Calvo-Guirado Jose Luis, Abboud Marcus, Ramirez-Fernandez Maria Piedad, Maté-Sánchez de Val José Eduardo, Negri Bruno, Gomez-Moreno Gerardo, Markovic Aleksa
Department of Prosthodontics and Digital Technology, School of Dental Medicine, Stony Brook University, Stony Brook, NY, USA.
Department of Implant Dentistry, Faculty of Medicine and Dentistry, Murcia University, Murcia, Spain.
Clin Implant Dent Relat Res. 2015 Aug;17(4):667-80. doi: 10.1111/cid.12161. Epub 2013 Oct 10.
To describe contact, thickness, density, and orientation of connective tissue fibers around healing abutments of different geometries by means of a new method using coordinates.
Following the bilateral extraction of mandibular premolars (P2, P3, and P4) from six fox hound dogs and a 2-month healing period, 36 titanium implants were inserted, onto which two groups of healing abutments of different geometry were screwed: Group A (concave abutments) and Group B (wider healing abutment). After 3 months the animals were sacrificed and samples extracted containing each implant and surrounding soft and hard tissues. Histological analysis was performed without decalcifying the samples by means of circularly polarized light under optical microscope and a system of vertical and horizontal coordinates across all the connective tissue in an area delimited by the implant/abutment, epithelium, and bone tissue.
In no case had the connective tissue formed a connection to the healing abutment/implant in the internal zone; a space of 35 ± 10 μm separated the connective tissue fibers from the healing abutment surface. The total thickness of connective tissue in the horizontal direction was significantly greater in the medial zone in Group B than in Group A (p < .05). The orientation of the fibers varied according to the coordinate area so that internal coordinates showed a higher percentage of parallel fibers in Group A (p < .05) and a higher percentage of oblique fibers in Group B (p < .05); medial coordinates showed more oblique fibers (p < .05); and the area of external coordinates showed the highest percentage of perpendicular fibers (p < .05). The fiber density was higher in the basal and medial areas (p < .05).
Abutment geometry influences the orientation of collagen fibers; therefore, an abutment with a profile wider than the implant platform favors oblique and perpendicular orientation of collagen fibers and greater connective tissue thickness.
通过一种新的坐标法描述不同几何形状愈合基台周围结缔组织纤维的接触、厚度、密度和方向。
从6只猎狐犬双侧拔除下颌前磨牙（P2、P3和P4），经过2个月的愈合期后，植入36枚钛种植体，在其上拧上两组不同几何形状的愈合基台：A组（凹形基台）和B组（更宽的愈合基台）。3个月后处死动物，提取包含每个种植体及周围软硬组织的样本。通过光学显微镜下的圆偏振光以及在由种植体/基台、上皮组织和骨组织界定区域内横跨所有结缔组织的垂直和水平坐标系统，对样本进行不脱钙的组织学分析。
在内侧区域，结缔组织在任何情况下都未与愈合基台/种植体形成连接；结缔组织纤维与愈合基台表面之间有35±10μm的间隙。B组内侧区域结缔组织在水平方向的总厚度显著大于A组（p<0.05）。纤维的方向根据坐标区域而变化，因此内侧坐标显示A组平行纤维的百分比更高（p<0.05），B组斜纤维的百分比更高（p<0.05）；内侧坐标显示更多斜纤维（p<0.05）；外侧坐标区域垂直纤维的百分比最高（p<0.05）。基底和内侧区域的纤维密度更高（p<0.05）。
基台几何形状影响胶原纤维的方向；因此，轮廓比种植体平台宽的基台有利于胶原纤维的倾斜和垂直方向以及更大的结缔组织厚度。
