Fig. 6. Comparison between short and high collar length (A and B)
Fig. 6. Comparison between short and high collar length (A and B)
Fig. 5. Mean rate ± SD of removal torque loss (%) between groups and results of ANOVA test for loss ratio of removal torque value between groups
Fig. 5. Mean rate ± SD of removal torque loss (%) between groups and results of ANOVA test for loss ratio of removal torque value between groups
Fig. 4. Application of cyclic loading with universal testing machine
Fig. 4. Application of cyclic loading with universal testing machine
Fig. 3. 3D scanning for abutment and designing for metal tube
Fig. 3. 3D scanning for abutment and designing for metal tube
Fig. 2. a Stainless steel split cylindrical mold with implant fixture screwed to abutment. b Implant fixture unscrewed from abutment after polymerization. c Implant fixture centralized vertically and perpendicular to the base with platform flushed with resin block level
Fig. 2. a Stainless steel split cylindrical mold with implant fixture screwed to abutment. b Implant fixture unscrewed from ...
Fig. 1. Different abutment angulations and collar lengths
Fig. 1. Different abutment angulations and collar lengths
N
Groups
Subgroups
Initial RTV
Postload RTV
Initial RTL
Postload RTL
...
Collar length
Subgroups
T test
A (2 mm collar length)
B (4 mm collar length)
t
P value
Initial RTV
...
Initial RTV
Postload RTV
Difference between initial and postload RTV
Mean ± SD
Subgroups
GIA
...
%initial RTL
%postload RTL
%difference between initial and postload RTL
Mean ± SD
Subgroups
GIA
...
El-Sheikh, M.A.Y., Mostafa, T.M.N. & El-Sheikh, M.M. Effect of different angulations and collar lengths of conical hybrid implant abutment on screw loosening after dynamic cyclic loading.
Int J Implant Dent 4, 39 (2018). https://doi.org/10.1186/s40729-018-0149-z
Download citation
Received: 07 May 2018
Accepted: 11 October 2018
Published: 03 December 2018
DOI: https://doi....
Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were m...
Not applicable
Not applicable.
Mai El-sheikh, Tamer Mostafa, and Mohamed El-Sheikh declare that they have no competing interests.
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Prosthodontic Department, Faculty of Dentistry, Tanta University, Elgeish St., Tanta, Egypt
Mai Ahmed Yousry El-Sheikh, Tamer Mohamed Nasr Mostafa & Mohamed Maamoun El-Sheikh
You can also search for this author in
PubMed Google Scholar
You can also search for this author in
PubMed Google Scholar
You can also search for this author in
...
Not applicable
Not applicable.
The authors declare that they have full control on all data and materials of this study.
Bickford JH, Nassar S. Handbook of bolts and bolted joints. New York: Marcel Dekker, Inc; 1998.
Dixon DL, Breeding LC, Sadler JP, McKay ML. Comparison of screw loosening, rotation, and deflection among three implant designs. J Prosthet Dent. 1995;74:270–8.
Hsu ML, Chung TF, Kao HC. Clinical applications of angled abutments - a literature review. Chin Dent J. 2005;24:15–21.
Morsch CS, Rafael...
Cavallaro JG, Greenstein G. Angled implant abutments. A Practical Application of Available Knowledge J Am Dent Assoc. 2011;142:150–8.
Kallus T, Henry P, Jemt T, Jorneus L. Clinical evaluation of angulated abutments for the Branemark system: a pilot study. Int J Oral Maxillofac Implants. 1990;5:39–45.
Herrero-Climent M, Romero-Ruiz MM, Diaz-Castro CM, Bullon P, Rios-Santos JV. Influence of tw...
Prado CJ, Neves FD, Soares CJ, Dantas KA, Dantas TS, Naves LZ. Influence of abutment screw design and surface coating on the bending flexural strength of the implant set. J Oral Implantol. 2014;40:123–8.
Goodacre CJ, Bernal G, Rungcharassaeng K, Kan JY. Clinical complications with implants and implant prostheses. J Prosthet Dent. 2003;90:121–32.
Michalakis KX, Calvani PL, Muftu S, Pissiotis ...
Within the limitations of this in vitro study, it can be concluded that:
Screw loosening increases with increasing abutment angulation and collar length after 100,000 cycles of dynamic cyclic loading.
Results of this study showed that conical hybrid connection design provides more biomechanically stable screw joint with straight abutments than angled abutments.
Several studies have been conducted on this type of implant–abutment connection [23, 34]. Sutter et al. [35] demonstrated reverse torque values of this hybrid implant–abutment connection that were 124% of the initial tightening torque. These authors suggested that cold welding occurred in the conical hybrid implant–abutment connection.
Schmitt et al. [36] compared conical and nonconical imp...
The increase in RTL with increasing abutment angulation can be attributed to the off-axis force as loading on angled abutments is mostly off-axis, which raises the concern of how angled abutments generally perform with such an unfavorable loading regimen [28]. Forces applied off-axis may be expected to overload the bone surrounding single-tooth implants, as shown by means of finite element analysi...
In the current study, the results showed that there is a significant difference in %RTL before and after application of dynamic cyclic loading for all angulations and collar lengths. These results are in an agreement with previous researches that found a significant difference between %initial and %postload RTL after mechanical cyclic loading [24, 25]. This result was explained by Bickford et al. ...
Conical hybrid connection was used in this study as it was proven that the conical hybrid demonstrated the best stress distribution [20]. This connection has a conical union between the implant fixture and the abutment. In the conical abutment, lateral force is resisted by the taper design of the Morse taper connection. Thus, the stress concentration is resisted by the side-wall contact surface of...
One-way ANOVA and pair-wise Tukey’s post hoc tests showed that %initial RTL among the groups was not significantly different (P > .05), while %postload RTL was significantly different among the three groups (P
Removal torque loss ratio before loading (%initial RTL)
Removal torque loss ratio after loading (%postload RTL)
Removal torque loss ratio between before and after loading (%difference between initial and postload RTL)
Student T test and ANOVA were used to compare mean of %initial and %postload RTL between different groups and subgroups followed by pair-wise Tukey’s post hoc tests at 0.05 leve...
Self-adhesive resin cement (G- CEM, USA) was used for fixing of metal tube to the abutment. A customized rigid metal mounting jig was designed, as a holding device, to ensure solid fixation of the sample while recording the measures.
Abutment screws were tightened in all the groups to 30 Ncm using a digital torque gauge (HTG2 - 200Nc, IMADA, Toyohashi, Japan) according to the manufacturer’s re...
Total 90 stock titanium abutments (Anyridges; MEGAGEN, Seoul, Korea) with different angulations and collar lengths were used in this study and divided into three groups, 30 each according to the degree of abutment angulations GI 0° abutment, GII 15° abutment, and GIII 25°. Each group was divided into two subgroups, 15 each according to implant abutment collar lengths: subgroup A (2 mm) and sub...
To date, there are limited publications regarding the investigation of screw loosening according to abutment angulations and collar lengths before and after dynamic cyclic loading. Sethi and colleagues [19] noted no implant fractures or screw loosening during a 96-month monitoring period for 2261 implants (N = 467 patients) with angulations ranging from 0 to 45°. While Asvanund and colleagues...
Collar length is the distance between the implant platform and the gingival margin. Sometimes, significant vertical space that has not been corrected with vertical ridge augmentation may necessitate selection of longer abutments, which would lead to an increased vertical cantilever. Furthermore, selection of the length of abutment collar would be affected if different distances between the implant...
When the implant set is submitted to functional loads, occlusal forces to the connection are concentrated at the abutment screw; consequently, the optimum preload is critical for joint stability and to avoid screw loosening [7].
Several factors related to screw design and fabrication can affect the risk of abutment or prosthetic screw loosening in a metal-to-metal screw system; these primarily ar...
Successful implant therapy requires a dynamic equilibrium between biological and mechanical factors. The mechanical factors are generally considered multifactorial which are involved in the success of implant rehabilitation. Majority of implant complications nowadays are caused by mechanical factors rather than the implant itself. Mechanical complications of the implant-prosthetic system include l...
The purpose of this in vitro study was to evaluate the effect of different angulations and collar lengths of the implant abutment on screw loosening by measuring removal torque value (RTV) before and after dynamic cyclic loading using digital torque gauge.
A total 90 sets of 4.5 mm diameter × 10 mm length bone level implants with conical hybrid connection were used. They were divided equally...
Fig. 8. Change in RTVs according to the numbers of mechanical loading cycles
Fig. 8. Change in RTVs according to the numbers of mechanical loading cycles
Fig. 7. Schematic diagram for experimental procedure
Fig. 7. Schematic diagram for experimental procedure
Fig. 6. Specimen mounted in a 30°-angled steel holder
Fig. 6. Specimen mounted in a 30°-angled steel holder
Fig. 5. Specimen mounted in a 30°-angled steel holder in ElectroPuls E1000 dynamic testing machine
Fig. 5. Specimen mounted in a 30°-angled steel holder in ElectroPuls E1000 dynamic testing machine
Fig. 4. Tightening the abutment screw and measuring the RTVs
Fig. 4. Tightening the abutment screw and measuring the RTVs
Fig. 3. Implant assembly embedded in resin block
Fig. 3. Implant assembly embedded in resin block
Fig. 2. Schematic of test setup according to The ISO 14801 recommendations
Fig. 2. Schematic of test setup according to The ISO 14801 recommendations
Fig. 1. Cone connection combined with octalobular index (Octatorx)
Fig. 1. Cone connection combined with octalobular index (Octatorx)
Benjaboonyazit, K., Chaijareenont, P. & Khongkhunthian, P. Removal torque pattern of a combined cone and octalobule index implant-abutment connection at different cyclic loading: an in-vitro experimental study.
Int J Implant Dent 5, 1 (2019). https://doi.org/10.1186/s40729-018-0154-2
Download citation
Received: 17 September 2018
Accepted: 20 December 2018
Published: 14 Jan...
Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were m...
Not applicable.
Not applicable.
Kanyarin Benjaboonyazit, Pisaisit Chaijareenont, and Pathawee, Khongkhunthian declare that they have no competing interests.
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Center of Excellence for Dental Implantology, Faculty of Dentistry, Chiang Mai University, Chiang Mai, Thailand
Kanyarin Benjaboonyazit
Department of Prosthodontics, Faculty of Dentistry, Chiang Mai University, Chiang Mai, Thailand
Pisaisit Chaijareenont
Center of Excellence for Dental Implantology, Faculty of Dentistry, Chiang Mai University, Suthep, A. Muang, Chiang Mai, 50200, Thailand
Pat...
The authors sincerely thank Mr. Anucharte Srijunbarl, Dental Material Research Center, Faculty of Dentistry, Chulalongkorn University for his assistance in the experimental part, Dr.Thanapat Sastraruji, Dental Research Center, Faculty of Dentistry, Chiang Mai University for his help in the meteorological data analysis and Dr. M. Kevin O Carroll, Professor Emeritus of the University of Mississippi ...
Khraisat A, Abu-Hammad O, Dar-Odeh N, Al-Kayed AM. Abutment screw loosening and bending resistance of external hexagon implant system after lateral cyclic loading. Clin Implant Dent Relat Res. 2004;6:43–164.
Guzaitis KL, Knoernschild KL, Viana MAG. Effect of repeated screw joint closing and opening cycles on implant prosthetic screw reverse torque and implant and screw thread morphology. J Pros...
Cibirka RM, Nelson SK, Lang BR, Rueggeberg FA. Examination of the implant-abutment interface after fatigue testing. J Prosthet Dent. 2001;85:268–75.
Khraisat A, Hashimoto A, Nomura S, Miyakawa O. Effect of lateral cyclic loading on abutment screw loosening of an external hexagon implant system. J Prosthet Dent. 2004;91:326–34.
Delben JA, Gomes EA, Barao VA, Assuncao WG. Evaluation of the eff...
Maeda Y, Satoh T, Sogo M. In vitro differences of stress concentrations for internal and external hex implant-abutment connections: a short communication. J Oral Rehabil. 2006;33:75–8.
Ma T, Nicholls JI, Rubenstein JE. Tolerance measurements of various implant components. Iny J Oral Maxillofac Implants. 1997;12:371–5.
Merz BR, Hunenbart S, Belser UC. Mechanics of the implant-abutment connect...
Pjetursson BE, Asgeirsson AG, Zwahlen M, Sailer I. Improvements in implant dentistry over the last decade: comparison of survival and complication rates in older and newer publications. Int J Oral Maxillofac Implants. 2014;29(Suppl):308–24.
Jung RE, Pjetursson BE, Glauser R, Zembic A, Zwahlen M, Lang NP. A systematic review of the 5-year survival and complication rates of implant-supported sing...
According to the conditions for the fatigue test set out in ISO 14801:2007, the RTVs of the combined cone and octalobule index reduced significantly after 50,000 cycles and did not change significantly until 2,000,000 cycles.
In addition, further studies are suggested to examine the relation between the settling value [38] and the preload value of the screw. It would be helpful for evaluating the stability of the implant-abutment connection after functional loading. The decreasing pattern of RTVs after cyclic loading was specific to the design of the implant-abutment connection, so more studies are recommended in other...
Tzenakis et al. [42] reported that retightening of the screw is strongly recommended, but the appropriate timing of retightening is still not clear. Cho et al. [39] recommended retightening abutment screws in the early stage of functional loading, at the first week in vivo, in internal type implants because they found no significant difference in RTVs between 20,000 and 100,000 cycles of loading...
Although the reduction in RTVs was observed after mechanical cyclic loading, no screw loosening occurred after 2,000,000 cycles of loading, which it assumed represents 3 years of function in worse scenario setting according to ISO 14801 in vivo [23]. Our study presents similar results to those of Binon and McHugh, who reported that the 30-N-cm insertion torque can maintain screw-joint stabilit...
From the study, the RTVs of the control group, which was left unloaded for 10 min after second tightening decreased 7.78% from the tightening torque. Previous studies have shown a 2 to 10% loss of screw preload [21]. These results can be explained by the settling effect as follows [16]. Firstly, the tightening torque is used to overcome the friction of the contacting metal surface connection [32...
The RTV data were normally distributed (Shapiro-Wilk test). The mean RTVs (N cm) of all groups are shown in Table 1. The RTVs in all groups decreased. The mean initial RTV of the control group was 27.67 N cm, a decrease of 7.78% compared to the insertion torque. After mechanical cyclic loading, all experimental groups from 50,000 to 2,000,000 cycles of loading showed significant decreases i...
Statistical analysis was performed using one-way ANOVA for the overall effect of the numbers of mechanical loading cycles on the RTVs of the abutment screw as well as the post hoc Tukey’s HSD test SPSS 20 (IBM SPSS, Chicago, IL, USA) was used, and differences at P
This study was conducted in accordance to the international standard fatigue test (ISO 14801:2007) for endosseous dental implants in vitro (Fig. 2). Eighty-four implants (PW Plus implant system, PW Plus Company) were prepared, which had a diameter of 3.75 mm and a length of 10 mm, with the Octatorx-cone implant-abutment connection. All were embedded in individual epoxy resin blocks (Chockfast ...
Bickford has explained how the screw is loosened in two stages [19]. Firstly, an external force causes micromovement and slipping between the abutment screw thread and the implant, decreasing the screw preload. Secondly, if the preload value falls below a critical level, and the external force exceeds the joint separating force, then screw loosening occurs. Consequently, the higher the preload val...
The occlusal force does not load only on the screw. The internal conical connection interface also helps to transfer and distribute the loading force to the implant [13]. The axial compressive component of occlusal force during oral function causes axial displacement of the abutment to the implant connection, increasing the frictional resistance and screw joint stability of the dental implant [7, ...
Dental implant placement has shown high survival and success rates [1, 2]. According to one study, the overall 5-year prosthetic survival rate for implant treatment has increased from 93.5 to 97.1% during the past 10 years [1]. Despite the high survival rate of implants, technical complications, such as screw loosening, are frequently reported [1,2,3]. The 5-year complication rate for screw loos...
Despite the high survival rate of dental implants, screw loosening is frequently reported. Screw loosening can cause a misfit of the implant-abutment connection leading to peri-implantitis or abutment screw fracture. Therefore, studies about related factors and mechanism of screw loosening are needed. The aim of this study was to evaluate the decreasing pattern of removal torque values (RTVs) of a...