2014 年 27 巻 3 号 p. 360-369
Although the alteration of bone level and density around functional dental implants was well documented, there was little information about their alteration in dental implants procedures.
The aim of the present study was to evaluate the postsurgical bone level around the submerged dental implants before the secondary operation. The digital intraoral radiographs taken for 52 implants were used in this study. The digital radiographs were obtained at the time immediately after the first surgery, and at 3 and 6 months after the surgery, but before the second surgery, by a digital intraoral radiography system. The digital images were manipulated by EMAGO, and then linear and logarithmic digital subtraction images were produced. The subtraction images were analyzed by ImageJ. The data was analyzed using one-way ANOVA, and a p-value of less than 0.05 was considered statistically significant.
As for the results, regarding the bone losses around the implants, the bone losses around the implants of 3.75 mm diameter were significantly higher than those around the implants of 5.0 mm diameter, both at 3 and 6 months after the first surgery (p<0.05). The bone losses around the implants of twist types were significantly higher than those around the implants of cylinder type (p<0.05). The bone losses in mandible were significantly higher than those in maxilla (p<0.05). The bone losses in women were significantly higher than those in men (p<0.05).
The results suggested that the alteration of bone level around the implants was dependent on the diameter and shape of the implants, the distinction between the maxilla and mandible, and gender. Therefore, these factors should be considered in the planning of dental implant procedures.