[A new technique for transcrestal sinus floor elevation with press-fit bone cylinders (dowel lift): short communication of the first in vitro results]

Rupture length of the sinus membrane after 1.2 mm puncture and surgical sinus elevation: an experimental animal cadaver study

OBJECTIVES

To evaluate the rupture length of the sinus membrane after applying a defined 1.2 mm defect comparing 3 different techniques: Summers lift, balloon-assisted technique (BASL), and hydrodynamic ultrasonic cavitational sinus lift (HUCSL).

STUDY DESIGN

Thirty fresh sheep heads (60 maxillary sinuses) were investigated. The sinus membrane was ruptured using a 1.2 mm pilot drill. Then Summers lift, BASL, and HUCSL were each performed on 20 sinuses, creating a 5 mm vertical lift of the sinus membrane. The length of the ruptured sinus membrane was measured before and after the experiment. The results of the different sinus lift techniques were compared using t tests.

RESULTS

The t test showed that the Summers lift leads to a significantly higher rupture length (P = .05) than BASL. The comparison between Summers lift and HUCSL showed a significantly higher rupture length with the Summers lift (P < .005). The same significance (P < .005) was found when BASL was compared with HUCSL. Comparing the increasing rupture length of the sinus membrane during the experiment, the t test showed a significantly greater rupture using BASL or the Summers lift compared with HUCSL.

CONCLUSIONS

The HUCSL technique yielded the lowest increase of rupture length compared with BASL and Summers lift. The technique therefore shows the lowest risk of a growing rupture of the sinus membrane in case of an iatrogenic puncture during preparation of the transcrestal approach.

Hydrodynamic ultrasonic sinus floor elevation--an experimental study in sheep

PURPOSE

The aim of the present study was to evaluate the pressure forces appearing to elevate the sinus membrane by comparing the hydraulic and pneumatic pressure. Also, the relation between the time and volume of the applied liquid and the achieved lift-volume were determined.

MATERIALS AND METHODS

A total of 190 fresh, half sheep heads were used for the present investigation. An ultrasound surgical device (Piezotome; Acteon, Bordeaux, France) was tested to evaluate the pressure increase at different flow rates. The elevation volume at different flow rates and activation times of the ultrasound hand piece were measured.

RESULTS

To detach the sinus membrane pneumatically from the sinus floor, a mean average pressure of 29.54 millibars was required. Using the hydraulic technique, a mean average pressure of 19.8 millibars was determined. Comparing the different flow rates, the elevated volume increased to 0.52 mL when a flow of 60 mL/minute was used. Using an activation time of 20 seconds, a lifted volume of 3.92 mL could be measured on average. If the flow was set to a maximum of 60 mL/minute, the created volume increased to 5.58 mL. A comparison using the chi(2) test showed a significant correlation (P = .03) between the application time and the created sinus lift volume. Even at high flow rates of 60 mL/minute of the activated Piezotome for a 20-second period, no rupture of the sinus membrane of the sheep heads occurred in 190 experiments.

CONCLUSION

From these results, we have concluded that hydrodynamic ultrasound could be used as an alternative method for sinus floor elevations of any size and volume with a mere 3-mm-diameter transcrestal approach, if findings from clinical investigations confirm the results of the present animal study.