Fig. 6. Immunohistochemical staining of osteocalcin (a) and collagen I (c) in sections from mini pigs mandible from 9M and IR osteocalcin (b) and collagen I (d). There were statistically significant differences to osteocalcin in 9M samples and no statistically significant differences to collagen I samples. Magnification: ×40 (a, b) and ×100 (c, d)
Fig. 6. Immunohistochemical staining of ost...
Fig. 5. Representative photomicrographs of each third of the peri-implant bone of IR experimental condition (H&E, ×40). a First third (cervical third). b Intermediate third. c Apical third. Note the edges of bone grooving present rounded contour, mainly in the last third
Fig. 5. Representative photomicrographs of each third of the peri-implant bone of IR experimental condition (H&E, ×40). a...
Fig. 4. Representative photomicrographs of each third of the peri-implant bone of 9M experimental condition (H&E, ×40). a First third (cervical third). b Intermediate third. c Apical third. Bone grooving with no altered contour
Fig. 4. Representative photomicrographs of each third of the peri-implant bone of 9M experimental condition (H&E, ×40). a First third (cervical third). b Intermediat...
Fig. 3. Prothesis fixed installed on the three implants
Fig. 3. Prothesis fixed installed on the three implants
9M
IR
Third
Mean
Standard deviation
Mean
...
9M
IR
Third
Mean
Standard deviation
Mean
...
Animal
Mean
Standard deviation
Minimum
Maximum
1
150.1
30.2
122.7
184.4
2
163.3
35.1
132.4
205.3
3
175.2
15.2
153.2
204.6
4
163.6
15.4
157.3
185.1
5
153.3
15.2
146.2
174.2
6
150.3
26.4
129.2
174.6
Table 2 Removal torque value (Ncm) of three implants removed after 9 months (9M) per animal
Animal
Mean
Standard deviation
Minimum
Maximum
1
98.3
5.5
92.2
103.3
2
91.6
9.1
82.1
102.5
3
105.3
8.3
100.4
115.0
4
71.6
10.5
61.2
82.2
5
78.6
5.8
72.7
83.1
6
88.6
6.6
81
93.6
Table 1 Removal torque value (Ncm) of three implants immediate removed (IR) per animal
Silva, R.d., Passador, F. & Caria, P.H.F. Twist removal of healed vs. nonhealed implants—a mechanical and histological study in mini pigs. Int J Implant Dent 2, 23 (2016). https://doi.org/10.1186/s40729-016-0059-x
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Received: 27 April 2016
Accepted: 18 November 2016
Published: 25 November 2016
DOI: https://doi.org/10.1186/s40729-016-0059-x
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...
FOP/UNICAMP, Piracicaba, SP, Brasil
Ricardo de Oliveira Silva & Paulo Henrique Ferreira Caria
CPG São Leopoldo Mandic, Campinas, SP, Brasil
Fabrício Passador
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Correspondence to Ricardo de Oliveira Silva.
We would like to thank Mario Perussi for supplying us with the customized system, implants, and prosthetic components, Dentifix®, FESB, veterinary professors Rafael Rodrigues and Alexander Correa Borghesan, and CAPES for the scholarship and financial support.
ROS conceived the study, held surgical procedures, and drafted the manuscript. FP did the preparation and helped in reading the histologic...
Yun H-M, Ahn S-J, Park K-R, Kim M-J, Kim J-J, Jin G-Z, et al. Magnetic nanocomposite scaffolds combined with static magnetic field in the stimulation of osteoblastic differentiation and bone formation. Biomaterials [Internet]. 2016;85:88–98. [cited 2016 Feb 10] Available from: http://www.sciencedirect.com/science/article/pii/S0142961216000491.
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Aubin JE, Liu F, Malaval L, Gupta AK. Osteoblast and chondroblast differentiation. Bone [Internet]. 1995;17(2):S77–83. [cited 2015 Dec 30] Available from: http://www.sciencedirect.com/science/article/pii/875632829500183E.
Mariano M. Minisuíno (minipig) na pesquisa biomédica experimental. O Minipig br1. Acta Cirúrgica Bras. 2003;18(5):387–91.
Herring SW. How can animal models answer clinic...
Piattelli A, Scarano A, Piattelli M. Microscopical aspects of failure in osseointegrated dental implants: a report of five cases. Biomaterials [Internet]. 1996;17(12):1235–41. [cited 2015 Oct 5] Available from: http://www.sciencedirect.com/science/article/pii/0142961296849441.
Stajčić Z, Stojčev Stajčić LJ, Kalanović M, Đinić A, Divekar N, Rodić M, et al. Removal of dental implants: re...
Assenza B, Scarano A, Perrotti V, Vozza I, Quaranta A, Quaranta M, et al. Peri-implant bone reactions around immediately loaded conical implants with different prosthetic suprastructures: Histological and histomorphometrical study on minipigs. Clin Oral Investig. 2010;14(3):285–90.
Sasaki H, Koyama S, Yokoyama M, Yamaguchi K, Itoh M SK. Bone metabolic activity around dental implants under loadi...
Glauser R, Sailer I, Wohlwend A, Studer S, Schibli M, Schärer P. Experimental zirconia abutments for implant-supported single-tooth restorations in esthetically demanding regions: 4-year results of a prospective clinical study. Int J Prosthodont [Internet]. 2004;17(3):285–90. [cited 2015 Oct 6] Available from: http://www.mendeley.com/catalog/experimental-zirconia-abutments-implantsupported-sing...
Brånemark PI. Osseointegration and its experimental background. J Prosthet Dent. 1983;50(3):399–410.
Chiapasco M, Gatti C. Immediate loading of dental implants placed in revascularized fibula free flaps: a clinical report on 2 consecutive patients. Int J Oral Maxillofac Implants. 2015;19(6):906–12.
Shemtov-Yona K, Rittel D. On the mechanical integrity of retrieved dental implants. J Mech Be...
Implant removal torque should be higher to remove implants with long-time installation than implants removed immediately after installation. Although, removal torque causes microscopical fractures and smooth on the peri-implant bone grooves, it does not compromised the bone healing.
According to Christenson R.H. [24], the bone structure, metabolism, and regulation are reflected by markers of resorption, formation, and/or turnover. Among the markers of bone resorption is the type 1 collagen degradation and maker of bone formation: Osteocalcin. Bone formation markers derive from the osteoblastic activity, formed during the different stages of osteoblasts proliferation, differen...
In order to better use a model which reproduce the natural conditions of dental implant in action, minipigs (BR-1) have been used in this study [44], the nonprimate animal model that is most appropriate for the study of human mastication [45] and commonly used in research because suine and human share important anatomic and physiologic characteristics [46, 47].
The osseointegration process is qui...
Dental implant revolutionized oral rehabilitation, becoming the natural teeth replacement by a titanium implant, a successful alternative to treat total or partial edentulism [14, 26, 27]. Nowadays, dental implants are definitely a current procedure in many dental offices [3, 28, 29]. Despite the long-term success shown by different studies [14, 30], implant failure is inevitable [31–33]. Since,...
Duplicate sections of peri-impant bone were obtained from each implant sample to evaluate the percentage of stained areas in order to differentiate markers of collagen I and osteocalcin within both experimental conditions (Fig. 6). The highest collagen I expression values were observed at the IR experimental condition, and osteocalcin expression was higher at the 9M.
There was a statistically si...
No remarkable complications were found during the healing period. At sacrifice, all 18 implants fixed after 9 months were considered successfully integrated at the time of the removal and none showed any mobility or signal of infection at sacrifice. There was no difference in the healing between animals who had the implants immediately removed after installation, and animal whose implants were re...
Hematoxylin-eosin-stained section images were digitized and analyzed in order to recognize the presence of native bone tissue by the presence of osteocyte lacunae-containing cells and the newly formed bone tissue recognized by the absence of lacunae. Also, the characteristics of peri-implant bone, presence or absence of bone fractures, and the shape and contour of bone grooving resultant of the tr...
The mandibles were sectioned into left and right segments, and each peri-implant bone was sectioned again to individualize them. Each peri-implant bone block was fixed in buffered formalin solution, pH 7.0, for 6 days, demineralized in 10% formic acid, and dehydrated through progressing alcohol concentrations and paraffin-embedded. Paraffin blocks were sectioned at 7-μm thick mounted on poly-l-...
This study was approved by the University Animal Ethics Committee-CEUA/UNICAMP-(Campinas, SP) (no.2730-1/12). Six adult male mini pigs (BR-1 mini pigs, São Paulo, Brazil) with ~36 months old and weighed ~55 kg were used in the experiment. The mini pigs were kept in the Experimental Center of the Veterinary Faculty (FESB-Bragança Paulista, SP) and were allowed to adapt to the environment 1 wee...
Many authors investigated bone reactions around dental implants [17–21]. What happens in the peri-implant bone implants removed is not reported in scientific articles. This study evaluated the peri-implant bone after his immediate removal and after 9 months of osseointegration. The aim of the present study was to evaluate the peri-implant bone after dental implant removal.
Since the discovery of osseointegration by Branemark in Sweden in 1960, where found that when titanium screws left undisturbed in bone, the osteocytes grow in close apposition to the titanium surfaces and provide firm anchorage. This discovery was successfully applied in dental and craniofacial reconstructive surgery in 1965 [1, 2]. Dental implants became a common procedure in the modern dental tr...
The objective of this study was to evaluate the effect of removal torque (reverse torque) of titanium implants in peri-implant bone.
The P1-M1 teeth were extracted bilaterally of 6 mini pigs (BR-1). Each animal received 6 titanium implants, three for each side of mandible. On the right side of mandible, 3 implants reminded 9 months (9M) under masticatory activity and on the left side, other 3 im...
Fig. 5. Mean and standard deviation of the biomechanical data at both observation periods (P > 0.05). a Removal torque. b Removal energy. c Connection stiffness
Fig. 5. Mean and standard deviation of the biomechanical data at both observation periods (P > 0.05). a Removal torque. b Removal energy. c Connection stiffness
Fig. 4. Comparison among secant and tangent methods to calculate the connection stiffness values, which reveals the absence of mathematical discrepancy
Fig. 4. Comparison among secant and tangent methods to calculate the connection stiffness values, which reveals the absence of mathematical discrepancy
Fig. 3. Representative curve of the torque test for implants. a Graph of torque versus angular displacement with linear regression curve, and equation, representing the connection stiffness. b Determination procedure of unscrewing implant work up to test’s maximum torque
Fig. 3. Representative curve of the torque test for implants. a Graph of torque versus angular displacement with linear r...
Fig. 2. Adaptation of Shimadzu universal testing machine for performing removal torque test of dental implants. a General view. b Assembly detail of connection between Allen keys socket and the implant placed in the tibia
Fig. 2. Adaptation of Shimadzu universal testing machine for performing removal torque test of dental implants. a General view. b Assembly detail of connection between Allen...
Fig. 1. Two pairs of implants (10 mm × 4 mm, L × Ø) from each of the experimental groups were placed in each tibia with an alternating fashion in terms of medio-distal positioning regarding the group, but with the first group chosen at random. Implants were placed with an inter-implant distance of 1 cm
Fig. 1. Two pairs of implants (10 mm × 4 mm, L × Ø) from each of...
Removal torque
Removal energy
Connection stiffness
Spearman’s rho
Removal torque
Coefficient
...
Sum of squares
df
Mean square
F
Sig. (P value)
Removal torque
Between groups
...
de Jesus, R.N.R., Carrilho, E., Antunes, P.V. et al. Interfacial biomechanical properties of a dual acid-etched versus a chemically modified hydrophilic dual acid-etched implant surface: an experimental study in Beagles.
Int J Implant Dent 4, 28 (2018). https://doi.org/10.1186/s40729-018-0139-1
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Received: 01 February 2018
Accepted: 29 May 2018
Published: 2...
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...
The animal experimental protocol was approved by the Bioethics Committee for Animal Experimentation (CEUA, protocol no. 098/10) at the Federal University of Uberlândia.
Rainde Naiara Rezende de Jesus, Eunice Carrilho, Pedro V. Antunes, Amílcar Ramalho, Camilla Christian Gomes Moura, Andreas Stavropoulos, and Darceny Zanetta-Barbosa declare that they have no competing interests.
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RNRJ participated in the study concept and design and performed the animal operations, biomechanical test, and data analysis and interpretation. EC, PVA, and AR contributed to define the test protocol and performed the biomechanical test and data analysis. CCGM and DZ participated in the study concept and desig...
Department of Periodontology, Faculty of Odontology, Malmö University, Carl Gustafs väg 34, 205-06, Malmö, Sweden
Rainde Naiara Rezende de Jesus & Andreas Stavropoulos
IBILI, Faculty of Medicine, University of Coimbra, Av. Bissaya Barreto, Bloco de Celas, 3000-075, Coimbra, Portugal
Rainde Naiara Rezende de Jesus & Eunice Carrilho
CEMUC, Mechanical Engineering Department, University of ...
The assistance of fifth-year dental students of the Federal University of Uberlândia in surgeries, including auscultation, and other practicalities is highly appreciated.
The Brazilian Federal Agency for Support and Evaluation of Graduate Education (CAPES research fellow, Full PhD Program, process no. 0975-14.1) provided funding and Neodent® (Curitiba, PR, Brazil) produced the titanium implants...
Kim S, Lee S, Cho I, Kim S, Kim T. Rotational resistance of surface-treated mini-implants. Angle Orthod. 2009;79(5):899–907. https://doi.org/10.2319/090608-466.1.
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de Jesus RNR, Stavropoulos A, Oliveira MTF, Soares PBF, Moura CCG, Zanetta-Barbosa D. Histomorphometric evaluation of a dual acid-etched vs. a chemically modified hydrophilic dual acid-etched implant surface. An experimental study in dogs. Clin Oral Implants Res. 2017;28(5):551–7. https://doi.org/10.1111/clr.12833.
Frost HM. Skeletal structural adaptations to mechanical usage (SATMU): 1. Redefi...
Boyan BD, Cheng A, Olivares-Navarrete R, Schwartz Z. Implant surface design regulates mesenchymal stem cell differentiation and maturation. Adv Dent Res. 2016;28(1):10–7. https://doi.org/10.1177/0022034515624444.
Mamalis AA, Silvestros SS. Analysis of osteoblastic gene expression in the early human mesenchymal cell response to a chemically modified implant surface: an in vitro study. Clin Oral ...
Wall I, Donos N, Carlqvist K, Jones F, Brett P. Modified titanium surfaces promote accelerated osteogenic differentiation of mesenchymal stromal cells in vitro. Bone. 2009;45(1):17–26. https://doi.org/10.1016/j.bone.2009.03.662.
Mamalis AA, Markopoulou C, Vrotsos I, Koutsilirieris M. Chemical modification of an implant surface increases osteogenesis and simultaneously reduces osteoclastogenesis...
Cochran DL, Jackson JM, Jones AA, Jones JD, Kaiser DA, Taylor TD, et al. A 5-year prospective multicenter clinical trial of non-submerged dental implants with a titanium plasma-sprayed surface in 200 patients. J Periodontol. 2011;82(7):990–9. https://doi.org/10.1902/jop.2011.100464.
Wallkamm B, Ciocco M, Ettlin D, Syfrig B, Abbott W, Listrom R, et al. Three-year outcomes of Straumann Bone Level...
Chemically modified sandblasted, large grit, and acid-etched surfaces
Sandblasted, large grit, and acid-etched surfaces
Neodent, Rua Benjamin Lins, 742, Curitiba, PR 80420–100, Brazil
Shimadzu Corporation, Nishinokyo Kuwabara-cho, Nakagyo-ku, Kyoto 604–8511, Japan
IBM Corporation v.23, 1 New Orchard Road, Armonk, New York 10, 504–1722, USA
No significant differences were observed between the specific hydrophilic (SAE-HD) and hydrophobic (SAE) surfaces evaluated in this study, in terms of biomechanical properties during the early osseointegration period.
In fact, the observed lack of differences between the groups could be attributed to the relatively low number of specimens per group. According to the observed data herein, applying a high power (80%) with the present sample size would had revealed a relatively large difference in removal torque equivalent to 43% between the experimental groups. Regarding removal energy and connection stiffness, t...
On the other hand, lack of significant differences between the two groups in the present experiment could be due to the fact that the effect of hydrophilicity, in terms of accelerating bone healing and osseointegration, was unfolded before the first evaluation time-point of 2 weeks, i.e., during the very early healing period. Consistently, pre-clinical investigations show the potential of chemica...
Improving surface wettability aims to increase the implant surface area achieving most favorable protein adsorption and cellular adhesion and thereby to positively regulate the biological response at the initial osseointegration process. Thus, the superior potential of superhydrophilic surfaces in enhancing osseointegration at early stages of bone formation may also enhance their load-bearing capa...
No remarkable events were observed during the surgical procedures and the subsequent healing period. The relative biomechanical performance of both experimental implant surfaces is illustrated in a representative graph of removal torque versus angular displacement. The removal torque, removal energy, and connection stiffness values are described in terms of mean, standard deviation, and 95% confid...
To assess the biomechanical strength of the bone-implant interface, the following parameters were assessed: (a) maximum removal torque (N cm) (primary outcome measure), obtained during the unscrewing process (primary outcome measure); (b) connection stiffness (N cm/rad), corresponding to the ratio between removal torque and angular displacement (secondary outcome measure); and (c) removal energy...
Six male Beagle dogs (~ 1.5 years old), weighting between 13 and 15 kg, were used in the present study. All animals were acclimatized in the experimental animal care facility of Federal University of Uberlândia for 2 weeks previously to the experimental procedures and randomly pair-housed in standard shelters (1 × 1.5 m kennel) to allow environmental enrichment (i.e., variety of toys, ...
The present preclinical in vivo study is reported according to the Animal Research: Reporting of In Vivo Experiments (ARRIVE) guidelines, in regard with relevant items [33]. The animal experimental protocol was approved by the Bioethics Committee for Animal Experimentation (CEUA, protocol no. 098/10) at the Federal University of Uberlândia and followed the normative guidelines of the National Cou...
Evaluation of biological effects and biomechanical properties of innovative technologies in the field of implant dentistry in preclinical animal models, prior to translational research, complies with standard regulations [33]. Thus, the aim of this preclinical animal study was to evaluate the effect of surface microtopography and chemistry on the biomechanical properties of implants with a sandbla...
The progressive evolution of oral implant surface technology (i.e., micro to nanotopography and chemical composition) [1, 2], implant macrogeometry, surgical procedures [3,4,5], and loading protocols [6,7,8] has resulted in high survival and clinical success rates [9]. Accordingly, chemically active micro and nanostructured implant surfaces, presenting moderate surface roughness (Ra/Sa values betw...
In this study, no significant differences were observed between the specific hydrophilic (SAE-HD) and hydrophobic (SAE) surfaces evaluated, in terms of biomechanical properties during the early osseointegration period.
The high survival clinical success rates of osseointegration are requisites for establishing a long-term biomechanical fixation and load-bearing potential of endosseous oral implants. The objective of this preclinical animal study was to evaluate the effect of surface microtopography and chemistry on the early stages of biomechanical rigidity with a sandblasted, dual acid-etched surface, with or w...
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
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Received: 07 May 2018
Accepted: 11 October 2018
Published: 03 December 2018
DOI: https://doi....
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Mai El-sheikh, Tamer Mostafa, and Mohamed El-Sheikh declare that they have no competing interests.
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Prosthodontic Department, Faculty of Dentistry, Tanta University, Elgeish St., Tanta, Egypt
Mai Ahmed Yousry El-Sheikh, Tamer Mohamed Nasr Mostafa & Mohamed Maamoun El-Sheikh
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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
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Received: 17 September 2018
Accepted: 20 December 2018
Published: 14 Jan...
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Kanyarin Benjaboonyazit, Pisaisit Chaijareenont, and Pathawee, Khongkhunthian declare that they have no competing interests.
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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...
Code
IT(N•cm)
RT(N•cm)
ISQ
12S
13.67 (1.88)
11.68 (1.06)
51.40 (2.95)
06D
20.19 (1.61)
17.45 (1.28)
53.77 (2.73)
06S
22.30 (1.78)
20.25 (2.47)
55.66(1.62)
Implant code
Thread type
Pitch (mm)
Lead (mm)
Lead angle (degree)
Total thread length (mm)
12S
Single-threaded
1.2
1.2
8.1
64
06D
Double-threaded
0.6
1.2
8.1
129
06S
Single-threaded
0.6
0.6
4.65
129
Figure 6. Bone debris at the contact interfaces. a Numbers of debris particles. b Number and size of debris particles. Each dot indicates a debris particle, and dashes indicate median particle sizes. Particle sizes: small, < 1000 μm2; medium, 1000–10000 μm2, and large, ≥ 10,000 μm2. c Particle size distribution
Figure 5. Microscopic analysis of contact interfaces. Microscopic observations of the artificial bone-implant and number of debris particles. The small arrows in the panel indicate voids in the implant-bone interface
Figure 4. Torque kinetics. Immediately after insertion terminated, the implant was removed using the same load and rotation speed. Torque kinetics were measured during implant insertion (top) and removal (bottom)
Figure 3. Comparison between IT and RT. Maximum IT value was measured when insertion was terminated. Immediately after insertion, the implant was removed, and the RT value was measured when removal commenced
Figure 2. Insertion torque (IT), removal torque (RT), and implant stability quotient (ISQ)
Figure 1. Implants. Implant code 12S is similar to a commercially available standard single-threaded implant with equal thread pitch and a 1.2-mm lead. The thread length of implant code 06D is doubled by adding the second thread (light blue). The thread length of implant code 06S is doubled by a 50% reduction in pitch and lead angles. Characteristics of each implant are summarized in Table 1
Fi...
References
Javed F, Ahmed HB, Crespi R, Romanos GE. Role of primary stability for successful osseointegration of dental implants: factors of influence and evaluation. Interv Med Appl Sci. 2013;5:162–7.
Falco A, Berardini M, Trisi P. Correlation between implant geometry, implant surface, insertion torque, and primary stability: in vitro biomechanical analysis. Int J Oral Maxillofac Implan...
Although bone models composed of a combination of cortical and cancellous bone are also available, this study used a single bone model with a homogeneous density to eliminate any effect of cortical bone and evaluate only the effect of design features on torque and ISQ values.
Experimental implant placement using artificial bone models is generally conducted to si...
Clinicians are advised to recognize the risk associated with using a multithreaded implant with a high lead angle, which may compromise primary stability because of greater bone tissue damage despite faster insertion. The question of placement speed warrants further consideration. Indeed, another advantage of double-threaded implants is placement speed. The implantation speed...
Moreover, the IT and RT values of 12S were consistent with those of the standard implant (Straumann) measured in our previous study. Here, the RT value of each implant was lower compared with their respective IT values, consistent with other reports. The IT and RT values of 06S were highest, followed by 06D and 12S. In contrast, the differences between RT and IT values were highest for...
In the artificial bone adjacent to 06D, there were more voids compared with those associated with 06S or 12S, which accounts for the increase in torque. The highest numbers and larger sizes of debris particles were associated with 06D, followed by 0S and 12S, indicating the potential for greater tissue damage. These results likely explain the lower (50%) torque value of 06S compared with tho...
Discussion
We show here that increasing thread length and reducing pitch can increase primary implant stability without changing the size of an implant. Compared with the standard single-threaded implant with a 1.2-mm pitch/lead (12S), torque values and ISQ were significantly increased by doubling the thread length by adding the second thread (06D) or by reducing pitch/lead and lead angle o...
Results
The IT, RT, and ISQ values revealed significant differences among the implants (Table 2).
The IT and RT values of 12S were not significantly different compared with published data (IT, 13.13 ± 1.763 N cm; RT, 12.37 ± 1.746 N cm) (Student t test, df = 9, t = 2.91, p < .017). Compared with 12S, the IT and RT values of 06D and 06S were significantly different (147% and 150%, a...
Methods
Implants
Three types of grade-4 titanium cylindrical nonself-tapping implants (codes 12S, 06D, and 06S) were specially designed and manufactured (Suwa Co., Ltd., Fujiyoshida, Yamanashi, Japan) (Fig. 1 and Table 1). The code 12S single-threaded implant served as a reference. Codes 06D and 06S were designed to double the thread length compared to 12S. Code 06D was a double-threated impla...
Introduction
Secure primary stability is positively associated with successful long-term implant integration to ensure a successful clinical outcome. Initial implant stability is defined as biomechanical stability upon insertion, which is influenced by factors such as bone quantity and quality, geometry of the implant, surgical technique, and insertion torque (IT). New bone develops around the ...
Effects of implant thread design on primary stability—a comparison between single- and double-threaded implants in an artificial bone model
Abstract
Background
Primary implant stability is essential for osseointegration. To increase stability without changing the implant size, the thread length must be extended by reducing pitch, using a double-threaded implant, or reducing pitch/lead a...
Figure 5. Torque-time curves of the MK3 and MK4. a Insertion torque. b Removal torque
Figure 4. Torque-time curves of the TE. a Insertion torque. b Removal torque
Figure 3. Torque-time curves of the BL. a Insertion torque. b Removal torque
Figure 2. Torque-time curves of the ST. a Insertion torque. b Removal torque
Figure 1. Compressed longitudinally to one third for characteristics of implant design. ST Straumann standard implant, MK3 Nobel Biocare MKIII, BL Straumann bone level implant, TE Straumann tapered effect implant, MK4 Nobel Biocare MKIV. Outer surface of implant (solid line). Inner surface of implant (dotted line)
Figure 1. Compressed longitudinally to one third for characteristics of implant d...
Initial area
Parallel area
Tapered area
Platform area
ST6
1.42 ± 0.43
0.31 ± 0.14
–
–
ST8
3.57 ± 1.62
0.35 ± 0.09
–
–
ST10
2.49 ± 0.81
0.45 ± 0.05
–
–
BL8
2.16 ± 0.21
0.50 ± 0.08
2.32 ± 0.52
–
BL10
1.96 ± 0.49
0.35+0.04
2.45+0.23
–
BL12
1.82 ± 0.27
0.33 ±...
Code
Insertion torque
Removal torque
Effective thread length (ETL)
(N · cm)
(N · cm)
(×π mm)
ST6
6.19 ± 0.716
5.95 ± 0.718
11.53
ST8
8.06 ± 1.038
9.09 ± 1.093
15.11
ST10
13.13 ± 1.763
12.37 ± 1.746
21.48
BL8
17.67 ± 1.290
16.67 ± 2.140
20.88
BL10
23.56 ± 1.628
21.99 ± 1.530
31....
System
Length
Pitch
Lead
Code
Manufacturer
(mm)
(mm)
(mm)
Standard RN
6, 8, 10
1.2
1.2
ST
Straumann
Bone Level RC
8, 10, 12
0.8
0.8
BL
Straumann
Tapered Effect RN
10
0.8
0.8
TE
Straumann
Brånemark MKIII
10
0.6
1.2
MK3
Nobel Biocare
Brånemark MKIV
10
0.6
1.2
MK4
Nobel Biocare
Abbreviations
BL:
Bone Level RC
IT:
insertion torque value
MK3:
Brånemark MKIII
MK4:
Brånemark MKIV
RT:
removal torque value
ST:
Standard RN
TE:
Tapered Effect RN
References
Friberg B, Sennerby L, Roos J, Johansson P, Strid CG, Lekholm U. Evaluation of bone density using cutting resistance measurements and microradiography. An...
Influence of cortical bone
The reason why a simulation test for only cancellous bone without cortical bone was performed in the present study has already been described. It was reported that bone density and the ratio of cortical bone and cancellous bone have influence on the primary stability of an implant and that higher primary stability is achieved with thread, even at the slightest lev...
Although the removal torque curves measured in the present study had similar shapes to one another, they were divided into two groups upon detailed observation, comprising a group of ST with parallel only, and a group of BL, TE, MK3, and MK4 having tapers and platforms. Since the thread contacts the artificial bone sequentially at the time of insertion, the torque curves showed the character...
This indicates that the friction at the time of rotating and pressing is greater than that at the time of rotating and cutting the bones with a tap and is a reasonable result. In the parallel area, the torque curve was a line with a moderate gradient, and the torque rise rate obtained from the gradient of the line was 0.36 N · cm/s. From this, it is estimated that the torque increase w...
Discussion
Insertion torque curve
In 2000, O’Sullivan reported torque curves for a prosthetic implant for the first time, and evaluated the characteristics of the tapered type by torque curves obtained by inserting five kinds of implants into the maxillary bone of unembalmed human cadavers. In a subsequent review, Meredith cited six kinds of torque curves when the final osteotomy diamete...
For the TE, the lower part of the implant was parallel and the lateral surface and axial surface had the same taper in the cervical region. TE10 in Fig. 4a showed a torque curve with a similar form to BL10 in Fig. 3 and had three kinds of areas. The torque curves for MK3 and MK4 in Fig. 4a had an area in which the torque finally rose suddenly after reaching its critical point and became moderate...
Results
Insertion torque
The insertion torque curve was divided into four regions. The first was the region where the torque rose suddenly immediately after insertion, which was seen in all implant bodies (shown as ① in the figure, and hereinafter called the initial area). The second was the region where the torque rose linearly with a moderate gradient, which was seen in all implant bodie...
Methods
Implants
The type of implant used for the experiments and the characteristics of its design are shown in Table 1 and Fig. 1, respectively. Figure 1 shows that the implant is compressed longitudinally to one third. The outer surface of the implant is indicated with a solid line, and the inner surface of the implant is indicated with a dotted line.
Preparation of an implant socket in ...
Background
Primary stability following implant placement is an essential condition for osseointegration. The primary stability is affected by the implant design, including surface-modifying or implant cavity-forming techniques, as well as by the bone quantity and bone density of the patient. In recent years, the interest of implant manufacturers and clinicians has shifted to the acquisition of ...
Abstract
Background
Primary stability following implant placement is essential for osseointegration and is affected by both implant design and bone density. The aim of this study was to compare the relationships between torque-time curves and implant designs in a poor bone quality model.
Methods
Nine implant designs, with five implants in each category, were compared. A total of 90 implants ...
Figure 6. Bone debris at the contact interfaces. a Numbers of debris particles. b Number and size of debris particles. Each dot indicates a debris particle, and dashes indicate median particle sizes. Particle sizes: small, < 1000 μm2; medium, 1000–10000 μm2, and large, ≥ 10,000 μm2. c Particle size distribution
Figure 5. Microscopic analysis of contact interfaces. Microscopic observations of the artificial bone-implant and number of debris particles. The small arrows in the panel indicate voids in the implant-bone interface
Figure 4. Torque kinetics. Immediately after insertion terminated, the implant was removed using the same load and rotation speed. Torque kinetics were measured during implant insertion (top) and removal (bottom)
Figure 2. Insertion torque (IT), removal torque (RT), and implant stability quotient (ISQ)
Table 2. Implants. Implant code 12S is similar to a commercially available standard single-threaded implant with equal thread pitch and a 1.2-mm lead. The thread length of implant code 06D is doubled by adding the second thread (light blue). The thread length of implant code 06S is doubled by a 50% reduction in pitch and lead angles. Characteristics of each implant are summarized in Table 1....
Code
IT(N•cm)
RT(N•cm)
ISQ
12S
13.67 (1.88)
11.68 (1.06)
51.40 (2.95)
06D
20.19 (1.61)
17.45 (1.28)
53.77 (2.73)
06S
22.30 (1.78)
20.25 (2.47)
55.66(1.62)
Implant code
Thread type
Pitch (mm)
Lead (mm)
Lead angle (degree)
Total thread length (mm)
12S
Single-threaded
1.2
1.2
8.1
64
06D
Double-threaded
0.6
1.2
8.1
129
06S
Single-threaded
0.6
0.6
4.65
129
The question of placement speed warrants further consideration. Indeed, another advantage of double-threaded implants is placement speed. The implantation speed of 06D was twice that of 06S, and implantation was completed twice as fast. Nevertheless, while plastic bottles and emergency valves have double-threaded screws for faster opening and closing, the effect...
Here, the RT value of each implant was lower compared with their respective IT values, consistent with other reports. The IT and RT values of 06S were highest, followed by 06D and 12S. In contrast, the differences between RT and IT values were highest for 12S, followed by 06D, and in 06S. We reported that the RT decreased more than IT. Thus, 06S had the lowest rate of decline (IT...
In the artificial bone adjacent to 06D, there were more voids compared with those associated with 06S or 12S, which accounts for the increase in torque. The highest numbers and larger sizes of debris particles were associated with 06D, followed by 0S and 12S, indicating the potential for greater tissue damage. These results likely explain the lower (50%) torque value of 06S compared wi...
In the artificial bone adjacent to 06D, there were more voids compared with those associated with 06S or 12S, which accounts for the increase in torque. The highest numbers and larger sizes of debris particles were associated with 06D, followed by 0S and 12S, indicating the potential for greater tissue damage. These results likely explain the lower (50%) torque value of 06S compared wi...
Discussion
We show here that increasing thread length and reducing pitch can increase primary implant stability without changing the size of an implant. Compared with the standard single-threaded implant with a 1.2-mm pitch/lead (12S), torque values and ISQ were significantly increased by doubling the thread length by adding the second thread (06D) or by reducing pitch/lead and lead angle o...
Results
The IT, RT, and ISQ values revealed significant differences among the implants (Table 2).
The IT and RT values of 12S were not significantly different compared with published data (IT, 13.13 ± 1.763 N cm; RT, 12.37 ± 1.746 N cm) (Student t test, df = 9, t = 2.91, p < .017). Compared with 12S, the IT and RT values of 06D and 06S were significantly different (147% and 150%, a...
Implants
Three types of grade-4 titanium cylindrical nonself-tapping implants (codes 12S, 06D, and 06S) were specially designed and manufactured (Suwa Co., Ltd., Fujiyoshida, Yamanashi, Japan) (Fig. 1 and Table 1). The code 12S single-threaded implant served as a reference. Codes 06D and 06S were designed to double the thread length compared to 12S. Code 06D was a double-threated implant with t...
Unfortunately, the effects of double- or triple-threaded implants on primary stability are known for only a few procedures, such as finite element analysis. An excessive lead angle for these implants may jeopardize their ability to sustain axial load despite faster insertion. Further, when micromotion is compared among implants with different lead angles with the same thread pitch, single-threaded...
Introduction
Secure primary stability is positively associated with successful long-term implant integration to ensure a successful clinical outcome. Initial implant stability is defined as biomechanical stability upon insertion, which is influenced by factors such as bone quantity and quality, geometry of the implant, surgical technique, and insertion torque (IT). New bone develops around the ...
Abstract
Background
Primary implant stability is essential for osseointegration. To increase stability without changing the implant size, the thread length must be extended by reducing pitch, using a double-threaded implant, or reducing pitch/lead and lead angle to half that of a single-threaded implant.
Materials and methods
We tested the stabilities of these configurations using artificial...