Temperature Changes during Implant Osteotomy Preparations in Human Cadaver Tibiae Comparing MIS® Straight Drills with Densah® Burs

Abstract

(1) Background: Several studies showed a sustained temperature of 47 °C or 50 °C for one minute resulted in vascular stasis and bone resorption with only limited bone regrowth over a 3–4-week healing period. The purpose of the present study was to evaluate the temperature changes (ΔΤ) that occur during the preparation of dental implant osteotomies using MIS® straight drills versus Densah® burs in a clockwise (cutting) drilling protocol. (2) Methods: Two hundred (240) osteotomies of two different systems’ drills were prepared at 6 mm depth at 800, 1000, and 1200 revolutions per minute (RPM), in fresh, unembalmed tibiae, obtained by a female cadaver. ΔΤ was calculated by subtracting the baseline temperature on the tibial surface, from the maximum temperature-inside the osteotomy (ΔT = Tmax − Tbase). The variables were evaluated both for their individual and for their synergistic effect on ΔΤ with the use of one-, two-, three- and four-way interactions; (3) Results: An independent and a three-way interaction (drill design, drill width, and RPM) was found in all three RPM for the Densah® burs and at 1000 RPM for the MIS® straight drills. As Densah® burs diameter increased, ΔΤ decreased. The aforementioned pattern was seen only at 1000 RPM for the MIS® straight drills. The usage of drills 20 times more than the implant manufacturers’ recommendation did not significantly affect the ΔΤ. A stereoscopic examination of the specimens confirmed the findings. (4) Conclusions: The independent and synergistic effect of drills’ diameter, design and RPM had a significant effect on ΔΤ in human tibiae, which never exceeded the critical threshold of 47 °C.

Effects of Osseodensification on Primary Stability of Cylindrical and Conical Implants—An Ex Vivo Study

“…When comparing the techniques, OD showed improved parameters for both conical and cylindrical implant macrogeometries. These results are in accordance with previous published in vitro and ex vivo animal studies [18,19,[28][29][30][31][32]42,47] which aimed to compare initial implant stability with/without OD bone instrumentation.…”

“…However, if we consider OD, these materials are not the best choice for a real evaluation, as there is no collagen in the synthetic blocks, and it has been established that this is crucial for the technique [18]. Therefore, studies of OD carried out on synthetic blocks usually do not show the same results as ex vivo animal [18,19,28,29,42,47,64], in vivo animal [20][21][22][23][30][31][32][33] or clinical studies [24][25][26][34][35][36][37][38][39][40]53,54].…”

“…A human cadaver study [29] tested the temperature changes during conventional and OD instrumentation, concluding that neither of the preparation systems tested caused an increasing in temperature that would interfere negatively with the osseointegration process.…”

Effect of Er:YAG Laser Exposure on the Amorphous Smear Layer in the Marginal Zone of the Osteotomy Site for Placement of Dental Screw Implants: A Histomorphological Study

“…Failure to meet the aforementioned conditions can result in bone overheating, leading to protein denaturation, enzyme inactivation, osteoblastic and osteoclastic necrosis and bone resorption. These factors can disrupt bone-implant integration and eventually lead to implant osseointegration failure [18,27]. According to several authors, controlling the heat generated during the procedure contributes to predictable and successful osseointegration [18].…”

“…The authors discuss the importance of not exceeding the temperature limit of 47 • C to prevent bone necrosis [1,17]. Various measures are being explored to reduce heat generation during osteotomy, including drill geometry and design, bone density and cortical thickness, single-stage or reciprocating drilling, use of reusable drills, internal or external cooling and the pressure applied by the operator during osteotomy [18].…”