Figure 3. Comparison of standard and over-dimensioned protocol. The figure displayed shows the comparison between standard and over-dimensioned protocol. a Displays the measurements obtained by RFA. The unit is ISQ with a range of 0 to 100 (minimum to maximum stability). b Displays the results obtained by the torque in and c by the torque out test. Although, there was no statistically s...
Figure 2. Over-dimensioned protocol. The over-dimensioned protocol was conducted by a final drill of 1 mm narrower than the implant diameter. The final drill for implants of 3.3. mm was 3.2 mm and of implants measuring 3.75 mm, it was 3.65 mm. Within this study, an over-dimensioned protocol was defined as a final drill larger than recommended by the company, which is in this case 4 o...
Figure 1. Standard protocol. This figure shows the implant types and drilling protocol used within this study. Standard protocol was conducted by a final drill of 2.80 mm for 3.3 mm implants, 3.20 mm for 3.75 mm implants, and 3.65 mm for 4.2 mm implants. Permissions for reproducing the figures were received from HI-TEC IMPLANTS LTD. Source: Product Catalogue 12th Edition [40]
3.3 mm
3.75 mm
4.2 mm
Mean (SD)
CI
Mean (SD)
CI
Mean (SD)
CI
ISQ
66.33 (4.59)
63.79–68.88
69.00 (5.98)
64.72–73.28
69.87 (8.88)
64.94–74.78
IT (Ncm)
102.65 (28.42)
86.91–118.39
90.97 (27.54)
71.27–110.67
78.19 (33.28)
59.76–96.62
TO (Ncm)
94.54 (29.09)
78.43–110.65
81.28 (28.89)
60.67–101.88
100.86 (36....
8.0 mm
10.0 mm
11.5 mm
13.0 mm
16.0 mm
Mean (SD)
CI
Mean (SD)
CI
Mean (SD)
CI
Mean (SD)
CI
Mean (SD)
CI
ISQ
65.5 (8.40)
58.48–72.52
73.17 (3.60)
69.39–76.95
67.11 (6.09)
62.43–71.79
66.15 (8.15)
59.43–73.07
70.67 (4.97)
66.84–74.49
IT (Ncm)
98.23 (18.56)
82.71–113.74
99.49 (43.73)
53.60–145.48
101.02 (36.80)
72.74–...
Insertion mode — manual insertion
Insertion mode — machine-driven insertion
n
Mean (SD)
CI
n
Mean (SD)
CI
ISQ
45
68.33 (6.83)
66.14–70.51
45
70.25 (5.52)
68.38–72.12
IT (Ncm)
45
90.56 (31.27)
80.56–100.56
45
83.94 (31.81)
73.17–94.7
TO (Ncm)
45
93.59 (32.3)
83.27–103.92
45
89.80 (37.32)
77.18–102.43
ISQ impla...
Drilling sequence — standard protocol
Drilling sequence — over-dimensioned protocol
n
Mean (SD)
CI
n
Mean (SD)
CI
ISQ
45
68.33 (6.83)
66.14–70.51
30
68.5 (8.82)
65.08–71.92
IT (Ncm)
45
90.56 (31.27)
80.56–100.56
30
63.74 (48.61)
44.89–82.59
TO (Ncm)
45
93.59 (32.3)
83.27–103.92
30
58.35 (40.43)
42.67–74.02
ISQ im...
Contrary to the research hypothesis, there was no difference in primary stability between manually and machine-driven inserted implants. To date, little is known about the influence of the insertion mode on the dental implant primary stability. Novsak et al. assumed a better primary stability in implants inserted manually and suspected that this behavior was related to a higher tac...
However, caution is recommended when using under-dimensioned drilling protocols: although high insertion torques ensure a greater initial implant stability and prevent adverse micromotions under loading, the induced over-compression could jeopardize the healing process. In addition, high stress is known to alter angiogenesis and impair new vessel formations, to induce local hypoxia and n...
Discussion
This study was performed in order to investigate changes in primary stability within an experimental setup of different insertion protocols and insertion modes. In order to obtain a high level of diagnostic certainty, three different methods for measurement of primary stability were recorded. As a secondary outcome parameter, potential differences between implants of different le...
Results
Drilling protocol: standard versus over-dimensioned
No statistically significant difference in RFA could be measured (Cohen’s d = − 0.022, effect size r = 0.011, p = 0.260), whereas IT values were significantly higher in implants inserted via SP (90.56 ± 31.27 Ncm) in comparison with the ODP (63.74 ± 48.61 Ncm, p = 0.002; Cohen’s d = 0.656, effect size r = 0.312). T...
Preparation protocol for oversized osteotomies (ODP)
This protocol repeated the steps of the standard protocol but then added a larger final drill. For the 3.3-mm implants, the final drill size was 3.2 mm; for the 3.75-mm implants, the final drill size was 3.65 mm (Fig. 2).
RFA
To analyze the data, an Osstell® SmartPeg threaded transducer (implant diameter 3.3 and 3.75 mm: SmartPeg Type ...
Methods
Bone specimens
Twenty mandibles from fresh porcine cadavers were obtained from a local slaughterhouse. The animals did not show any macroscopic signs of any pathologic bone conditions. After removal of the surrounding soft tissue, the surfaces of the bone samples were thoroughly cleaned. Each sample was checked macroscopically for irregularities and a minimum thickness of 20 mm at th...
Analyzing those, a decrease in primary and an increase in secondary stability with a shorter healing period for implants became apparent. Kim et al. compared the effect of oversized drilling sockets regarding bone-to-implant contact and bone density after 4 and 8 weeks in an in vivo dog model. They used a final drill of 4.00 mm for implants with a diameter of 4 mm in the oversized group and a ...
With increasing stiffness of the bone-implant interface, the vibration frequency of the sensor increases. While RFA is expressed in hertz, implant stability quotient (ISQ) is the scale used to quantify RFA values (range 1–100).
Even though RFA has been reported to be a reliable, reproducible, and objective method to measure the stiffness of bone-implant-complex, it has also been reported that R...
Background
A reliable option for replacing teeth is the insertion of osseointegrated implants. Dental implant primary stability (DIS) has also been reported to be a fundamental prerequisite for long-term success of dental implants, even though osseointegration has also been achieved without a certain amount of primary stability. Primary stability has been defined as the ability to withstand axi...
Abstract
Background
Dental implant primary stability is thought to be a fundamental prerequisite for the long-term survival and success. The aim of this study was to analyze the influence of protocol and insertion mode on dental implant stability ex vivo. One hundred and twenty implants were inserted either manually or machine-driven into porcine mandibles by a standard or over-dimensioned pro...