7 research outputs found
Height difference between the vestibular and palatal walls and palatal width: a cone beam computed tomography approach
Background: The objective of this study was to measure two parameters involved in tri-dimensional implant planâ
ning: the position of the buccal and palatal bone wall and the palatal thickness.
Methods: Cone beam computed tomography (CBCT) images (Planmeca ProMax 3D) of 403 teeth (208 upper teeth
and 195 lower teeth) were obtained from 49 patients referred to the Dental School of Seville from January to Decemâ
ber 2014. The height diference between the palatal and buccal walls was measured on the most coronal point of
both walls. The thickness of the palatal wall was measured 2 mm from the most coronal point of the palatal wall.
Results: The mean values in the maxilla were 1.7±0.9 mm for central and lateral incisors, 2.2±1.7 mm for canines,
1.6±0.9 mm for premolars and 1.9±1.5 mm for molars. In the lower jaw, the mean values were 1.3±0.8 mm for inciâ
sors, 1.7±1.2 mm for canines, 2.3±1.3 mm for premolars, and 2.6±1.7 mm for molars. In the upper jaw, more than
55% of maxillary teeth (excluding second premolars and molars) presented mean height diferences greater than
1 mm. In the mandible, more than 60% of incisors showed a buccal bone thickness of 1 mm from the apical to lingual
aspect. All teeth except the second premolar presented a buccal wall located more than 1 mm more apically than the
lingual bone wall.
Conclusions: The buccal bone wall is located more apically (greater than 1 mm) than the palatal or lingual table in
most of the cases assessed. The thickness of the palatal or lingual table is also less than 2 mm in the maxilla and manâ
dible, except in the upper canines and premolars and the lower molars
Relevant Design Aspects to Improve the Stability of Titanium Dental Implants
Post-extractional implants and immediate loading protocols are becoming much more
frequent in everyday clinical practice. Given the existing literature about tapered implants, the
objective of this paper was to understand whether implant shape had a direct influence on the
results of the insertion torque (IT) and implant stability quotient (ISQ). Seven tapered implant
prototypes were developed and distributed into three groups and compared with a control cylindrical
implantâVEGA by Klockner Implant System. The implants were inserted into bovine bone type III
according to Lekholm and Zarb Classification. The sample size was n = 30 for the three groups. Final
IT was measured with a torquemeter, and the ISQ was measured with Penguin Resonance Frequency
Analysis (RFA). Modifications done to the Prototype I did not reveal higher values of the ISQ and IT
when compared to VEGA. In the second group, when comparing the five prototypes (IIâVI) with
VEGA, it was seen that the values of the ISQ and IT were not always higher, but there were two
values of the ISQ that were statistically significantly higher with the 4.0 mm diameter Prototypes II
(76.3 ± 6.1) and IV (78 ± 3.7). Prototype VII was the one with higher and significant values of the ISQ
and IT. In both diameters and in both variables, all differences were statistically significant enough
to achieve the higher values of primary stability values (IT and ISQ). Given the limitations of this
study, it can be concluded that when there is an increase of the diameter of the implant and body
taper, there is an increase of the ISQ and IT, showing that the diameter of the implant is an important
criteria to obtain higher values of primary stability
Is It Possible to Monitor Implant Stability on a Prosthetic Abutment? An In Vitro Resonance Frequency Analysis
In order to apply the âone-abutmentâone-timeâ concept, we evaluated the possibility of
measuring resonance frequency analysis (RFA) on the abutment. This trial aimed to compare the
Implant Stability Quotient (ISQ) values obtained by the PenguinRFA when screwing the transducer
onto the implant or onto abutments with different heights and angulations. Eighty implants (VEGAÂź,
Klockner Implant System, SOADCO, Les Escaldes, Andorra) were inserted into fresh bovine ribs.
The groups were composed of 20 implants, 12 mm in length, with two diameters (3.5 and 4 mm).
Five different abutments for screwed retained restorations (PermanentÂź) were placed as follows:
straight with 1, 2, and 3 mm heights, and angulated at 18⊠with 2 and 3 mm heights. The mean value
of the ISQ measured directly on the implant was 75.72 ± 4.37. The mean value of the ISQ registered
over straight abutments was 79.5 ± 8.50, 76.12 ± 6.63, and 71.42 ± 6.86 for 1, 2, and 3 mm height
abutments. The mean ISQ over angled abutments of 2 and 3 mm heights were 68.74 ± 4.68 and
64.51 ± 4.53 respectively. The present study demonstrates that, when the ISQ is registered over the
straight abutments of 2 and 3 mm heights, the values decrease, and values are lower for angled, 3 mm
height abutments