ABSTRACT
Objectives@#The stability of crestal bone has been reported as a major factor in the success of dental implants. Implants can be placed in an equicrestal (crestal) or subcrestal position. The aim of this study was to evaluate the effect of implant depth placement on marginal bone loss. @*Materials and Methods@#The study was created in a split-mouth design. Immediately after implant surgery, digital parallel radiographs were prepared and levels of bone were measured where marginal bone loss and bone level changes occurred. These measurements were repeated at 3-month and 6-month follow-up periods. @*Results@#In this interventional study, 49 implants were evaluated in 18 patients. Primary bone height was not significant between the intervention and control groups in both mesial and distal aspects at 3 months and 6 months from the baseline. The mean marginal bone loss on the mesial side was 1.03 mm in the subcrestal group and 0.83 mm in the crestal group. In addition, mean marginal bone loss on the distal side was 0.88 mm and 0.81 mm in the subcrestal and crestal groups, respectively. Marginal bone loss was not significantly different between sexes, the maxilla or mandible, and in the anterior or posterior regions as well as between different lengths and diameters of implants. @*Conclusion@#Based on the results of this study, there was no significant difference in terms of marginal bone loss between crestal and subcrestal implants.
ABSTRACT
Contemporary cephalometric analysis in orthodontics is based on comparison between craniofacial portions and reference planes. One of these planes is Frankfort Horizontal [FH] Plane that can be made by anatomic portion or machine portion. The aim of this study was to determine and compare the angle between Anatomic Frankfort Horizontal plane [AFH] and True Horizontal [TH] with the angle formed by Machine Frankfort Horizontal plane [MFH] and TH. Materials. In this Analytical-descriptive study, digital lateral cephalograms were taken in Natural Head Position from 50 orthodontic patients with the minimum age of 14 and class I malocclusion [Viazis analysis on Onyx Ceph software was employed to confirm the class I malocclusion]. Then on each cephalogram, two FH planes were constructed using machine and anatomic portions. Then the angle between each FH plane and TH plane was measured and recorded. Finally, the data were analyzed by paired Mest [a=0.05]. Machine Frankfort Horizontal plane [MFH] and Anatomic Frankfort Horizontal plane [AFH] showed significant differences of-5,66 and -1.58 degrees with True Horizontal plane [TH] respectively [P<0.001]. For cephalometric evaluation in orthodontic patients if the Frankfurt plane be used, it is better to use anatomical portion, because the difference between the Anatomic Frankfort Horizontal plane [AFH] and True Horizontal plane [TH] is significantly less than the difference between the Machine Frankfort Horizontal plane [MFH] and True Horizontal plane [TH]