Rahmanivahid Heidari 2021a - Revision history

Rimni at 11:18, 7 March 2022

2022-03-07T11:18:41Z

Show changes

Rimni at 11:07, 7 March 2022

2022-03-07T11:07:00Z

Rimni at 10:10, 4 March 2022

2022-03-04T10:10:52Z

Rimni at 15:38, 3 March 2022

2022-03-03T15:38:51Z

Rimni at 15:51, 2 March 2022

2022-03-02T15:51:14Z

Show changes

Rimni at 13:33, 2 March 2022

2022-03-02T13:33:51Z

Rimni at 13:33, 2 March 2022

2022-03-02T13:33:41Z

Rimni: /* 3.2 Abutment and crown */

2022-03-02T13:33:17Z

‎3.2 Abutment and crown

Rimni at 13:33, 2 March 2022

2022-03-02T13:33:01Z

Rimni at 13:32, 2 March 2022

2022-03-02T13:32:36Z

@@ Line 114: / Line 114: @@
 ===2.4 Implant length===
-The distance between the platform and the apex of dental implants is defined as implant length. In implant dentistry, it is assumed that longer implants are associated with a higher success rate. Though, there is no proven document or investigations that prove the linear relationship between implant success and length. However, a 7 mm length implant has shown the highest failure rate compared to other sizes. Longer dental implants can increase implant stability to a limited certain degree. Since short dental implants have a small contact surface, and occlusal forces need to be contributed over the implant-bone interface area to avoid inappropriate stress levels, short implants are not recommended in dentistry. In a finite element study of Lee et al., it is shown that masticatory forces generate stress over the cortical bone interface and not the cancellous area. Since occlusal forces are usually small in amount, cortical bone can tolerate the generated stress. Therefore, implant diameter especially in the crestal bone area is a more important factor compared to the length. Clinical reports have shown a high failure rate for implants shorter than 7 mm. It is believed that bone type and interface area are more significant parameters in implant stability than implant length. It should be taken into consideration that short dental implants are usually used for the posterior maxilla that has lower bone quality [25].
+The distance between the platform and the apex of dental implants is defined as implant length. In implant dentistry, it is assumed that longer implants are associated with a higher success rate. Though, there is no proven document or investigations that prove the linear relationship between implant success and length. However, a 7 mm length implant has shown the highest failure rate compared to other sizes. Longer dental implants can increase implant stability to a limited certain degree. Since short dental implants have a small contact surface, and occlusal forces need to be contributed over the implant-bone interface area to avoid inappropriate stress levels, short implants are not recommended in dentistry. In a finite element study of Lee et al., it is shown that masticatory forces generate stress over the cortical bone interface and not the cancellous area [25]. Since occlusal forces are usually small in amount, cortical bone can tolerate the generated stress. Therefore, implant diameter especially in the crestal bone area is a more important factor compared to the length. Clinical reports have shown a high failure rate for implants shorter than 7 mm. It is believed that bone type and interface area are more significant parameters in implant stability than implant length. It should be taken into consideration that short dental implants are usually used for the posterior maxilla that has lower bone quality [25].
 In a study by İplikçioğlu and Akça, lower compressive and tensile stresses were seen for wider implants and it was concluded that length does not decrease stress values. In this study, stress levels in two wide supported implants with a diameter of 4.1 mm have been compared with three implants supported prostheses with a 3.75 mm diameter. The magnitude of stress distribution in the surrounding cortical bone was lower for the two-unit supported implants than the three units. The results showed that wider diameter has the greatest effect on stress level and changes in length and number of units do not decrease the magnitude of stress [30].

@@ Line 180: / Line 180: @@
 [4]	Haas R., Mailath‐Pokorny G., Dörtbudak O., Watzek G., Polak C., Fürhauser R. A long‐term follow‐up of 76 Brånemark single‐tooth implants. Clinical Oral Implants Research, 13(1):38-43, 2002.
-[5]	VanSchoiack, L.R., Wu, J.C., Sheets, C.G., Earthman, J.C. Effect of bone density on the damping behavior of dental implants: An in vitro method. Materials Science and Engineering: C, 26(8):1307-1311, 2006.
+[5]	VanSchoiack L.R., Wu J.C., Sheets C.G., Earthman J.C. Effect of bone density on the damping behavior of dental implants: An in vitro method. Materials Science and Engineering: C, 26(8):1307-1311, 2006.
 [6]	Li W., Lin D., Rungsiyakull C., Zhou S., Swain M., Li Q. Finite element based bone remodeling and resonance frequency analysis for osseointegration assessment of dental implants. Finite Elements in Analysis and Design, 47(8):898-905, 2011.
@@ Line 190: / Line 190: @@
 [9]	Åstrand P., Engquist B., Dahlgren S., Gröndahl K., Engquist E., Feldmann H. Astra Tech and Brånemark system implants: a 5‐year prospective study of marginal bone reactions. Clinical Oral Implants Research, 15(4):413- 420, 2004.
-[10]	Moberg L., Sagulin G., Köndell P., Heimdahl A., Gynther, G.W., Bolin, A. Branemark system and ITI dental implant system® for treatment of mandibular edentulism. Clinical Oral Implants Research, 12(5):450-461, 2001.
+[10] Moberg L., Sagulin G., Köndell P., Heimdahl A., Gynther G.W., Bolin A. Branemark system and ITI dental implant system® for treatment of mandibular edentulism. Clinical Oral Implants Research, 12(5):450-461, 2001.
 [11]	Steenberghe D., Mars G., Quirynen M., Jacobs R., Naert I. A prospective split‐mouth comparative study of two screw‐shaped self‐tapping pure titanium implant systems. Clinical Oral Implants Research, 11(3):202-209, 2000.
@@ Line 204: / Line 204: @@
 [16]	Skalak R. Biomechanical considerations in osseointegrated prostheses. Journal of Prosthetic Dentistry, 49(6):843-848, 1983.
-[17]	Hansson S., Werke M. The implant thread as a retention element in cortical bone: the effect of thread size and thread profile: a finite element study. Journal of Biomechanics, 36(9):1247-1258, 2003.
+[17] Hansson S., Werke M. The implant thread as a retention element in cortical bone: the effect of thread size and thread profile: a finite element study. Journal of Biomechanics, 36(9):1247-1258, 2003.
-[18]	Geng J., Ma Q., Xu W., Tan K., Liu, G. Finite element analysis of four thread‐form configurations in a stepped screw implant. Journal of Oral Rehabilitation, 31(3):233-239, 2004.
+[18]	Geng J., Ma Q., Xu W., Tan K., Liu G. Finite element analysis of four thread‐form configurations in a stepped screw implant. Journal of Oral Rehabilitation, 31(3):233-239, 2004.
 [19]	Lee C., Lin S., Kang M., Wu S., Fu P. Effects of implant threads on the contact area and stress distribution of marginal bone. Journal of Dental Sciences, 5(3):156-165, 2010.
-[20]	Patra A.K., DePaolo J.M., D’Souza K.S., DeTolla D., Meenaghan M.A. Guidelines for analysis and redesign of dental implants. Implant Dent., 7(4):355-368, 1998.
+[20]	Patra A.K., DePaolo J.M., D’Souza K.S., DeTolla D., Meenaghan M.A. Guidelines for analysis and redesign of dental implants. Implant Dentistry, 7(4):355-368, 1998.
 [21]	Chun H.J., Cheong S.Y., Han J.H. Evaluation of design parameters of osseointegrated dental implants using finite element analysis. Journal of Oral Rehabilitation, 29:565−74, 2002.
@@ Line 216: / Line 216: @@
 [22]	Albrektsson T., Branemark P.I., Hansson H.A., Kasemo, B. The interface zone of inorganic implants in vivo: titanium implants in bone. Annals in Biomedical Engineering, 11:1–27, 1983.
-[23]	Van Oosterwyck, H., Duyck, J., Van der Sloten, J., Van der Perre, G., De Cooman, M., Lievens S., Puers R., Naert I. The influence of bone mechanical properties and implant fixation upon bone loading around oral implants. Clinical Oral Implants Research, 9:407–418, 1998.
+[23]	Van Oosterwyck H., Duyck J., Van der Sloten J., Van der Perre G., De Cooman M., Lievens S., Puers R., Naert I. The influence of bone mechanical properties and implant fixation upon bone loading around oral implants. Clinical Oral Implants Research, 9:407–418, 1998.
-[24]	Arni, U., Weissberg, I., Gihon, O. Hybrid dual thread screw implant-analytical and experimental research, ARDS Implants, 2007.
+[24]	Arni U., Weissberg I., Gihon O. Hybrid dual thread screw implant-analytical and experimental research. ARDS Implants, 2007.
 [25]	Lee J., Frias V., Lee K., Wright R.F. Effect of implant size and shape on implant success rates: a literature review. Journal of Prosthetic Dentistry, 94(4):377-381, 2005.
-[26]	Kong L., Zhao Y., Hu K., Li, D., Zhou H., Wu Z., Liu, B. Selection of the implant thread pitch for optimal biomechanical properties: a three-dimensional finite element analysis. Advances in Engineering Software, 40(7):474-478, 2009.
+[26]	Kong L., Zhao Y., Hu K., Li D., Zhou H., Wu Z., Liu B. Selection of the implant thread pitch for optimal biomechanical properties: a three-dimensional finite element analysis. Advances in Engineering Software, 40(7):474-478, 2009.
 [27]	Geramy A., Morgano S.M. Finite element analysis of three designs of an implant-supported molar crown. Journal of Prosthetic Dentistry, 92(5):434-440, 2004.
@@ Line 240: / Line 240: @@
 [34]	Hsu C., Chao C., Wang J., Hou S., Tsai Y., Lin J. Increase of pullout strength of spinal pedicle screws with conical core: biomechanical tests and finite element analyses. Journal of Orthopaedic Research, 23(4):788-794, 2005.
-[35]	Kwok A.W.L., Finkelstein J.A., Woodside T., Hearn T.C., Hu R.W. Insertional torque and pull-out strengths of conical and cylindrical pedicle screws in cadaveric bone. Spine, 21(21):2429-34, 1996.
+[35]	Kwok A.W.L., Finkelstein J.A., Woodside T., Hearn T.C., Hu R.W. Insertional torque and pull-out strengths of conical and cylindrical pedicle screws in cadaveric bone. Spine, 21(21):2429-2434, 1996.
 [36]	Abshire B.B., McLain R.F., Valdevit A., Kambic H.E. Characteristics of pullout failure in conical and cylindrical pedicle screws after full insertion and back-out. The Spine Journal, 1(6):408-414, 2001.

@@ Line 242: / Line 242: @@
 [35]	Kwok A.W.L., Finkelstein J.A., Woodside T., Hearn T.C., Hu R.W. Insertional torque and pull-out strengths of conical and cylindrical pedicle screws in cadaveric bone. Spine, 21(21):2429-34, 1996.
-[36]	Abshire B.B., McLain R.F., Valdevit A., Kambic H.E. Characteristics of pullout failure in conical and cylindrical pedicle screws after full insertion and back-out. Spine J. 1:408-1, 2001.
+[36]	Abshire B.B., McLain R.F., Valdevit A., Kambic H.E. Characteristics of pullout failure in conical and cylindrical pedicle screws after full insertion and back-out. The Spine Journal, 1(6):408-414, 2001.
-[37]	Ono A., Brown M.D., Latta L.L., Milne E.L., Holmes D.C. Triangulated pedicle screw construct technique and pull-out strength of conical and cylindrical screws. J Spinal Disord.14:323-9, 2001.
+[37]	Ono A., Brown M.D., Latta L.L., Milne E.L., Holmes D.C. Triangulated pedicle screw construct technique and pull-out strength of conical and cylindrical screws. Journal of Spinal Disorders, 14:323-329, 2001.
-[38]	Choi W, Lee S, Kim JW, Kim JK, Goel V. Assessment of pullout strength of various pedicle screw designs in relation to the changes. In: 48th Annual Meeting of the Orthopaedic Research Society, 2002.
+[38]	Choi W., Lee S., Kim J.W., Kim J.K., Goel V. Assessment of pullout strength of various pedicle screw designs in relation to the changes. In: 48th Annual Meeting of the Orthopaedic Research Society, 2002.
-[39]	Lill CA, Schlegel U, Wahl D, Schneider E. Comparison of the in vitro holding strengths of conical and cylindrical pedicle screws in a fully inserted setting and backed out 180 degrees. J Spinal Disord 13:259-66, 2000.
+[39]	Lill C.A., Schlegel U., Wahl D., Schneider E. Comparison of the in vitro holding strengths of conical and cylindrical pedicle screws in a fully inserted setting and backed out 180 degrees. Journal of Spinal Disorders, 13:259-266, 2000.
-[40]	Rieger M., Adams W. and Kinzel G. A finite element survey of eleven endosseous implants. The Journal of prosthetic dentistry, 63(4):457-465, 1990.
+[40]	Rieger M., Adams W., Kinzel G. A finite element survey of eleven endosseous implants. The Journal of Prosthetic Dentistry, 63(4):457-465, 1990.
-[41]	Rieger M., Fareed K., Adams W. and Tanquist R. Bone stress distribution for three endosseous implants. The Journal of prosthetic dentistry, 61(2):223-228, 1989.
+[41]	Rieger M., Fareed K., Adams W., Tanquist R. Bone stress distribution for three endosseous implants. The Journal of Prosthetic Dentistry, 61(2):223-228, 1989.
-[42]	Bozkaya D. and Müftü S. Mechanics of the tapered interference fit in dental implants, Journal of Biomechanics, 36(11):1649-1658, 2003.
+[42]	Bozkaya D., Müftü S. Mechanics of the tapered interference fit in dental implants. Journal of Biomechanics, 36(11):1649-1658, 2003.
-[43]	Burguete R.L., Johns R.B., King T. and Patterson E.A. Tightening characteristics for screwed joints in osseointegrated dental implants', The Journal of prosthetic dentistry, 71(6): 592-599, 1994.
+[43]	Burguete R.L., Johns R.B., King T., Patterson E.A. Tightening characteristics for screwed joints in osseointegrated dental implants. The Journal of Prosthetic Dentistry, 71(6):592-599, 1994.

@@ Line 167: / Line 167: @@
 ==Acknowledgement==
-We acknowledge Global College of Engineering and Technology of Oman for supporting this study
+We acknowledge Global College of Engineering and Technology of Oman for supporting this study.
 ==References==

@@ Line 163: / Line 163: @@
 ==Conclusion==
-Dental implants are used to replace partial or fully edentulous patients. The dental implant industry will probably produce screw-shaped implants with different thread configurations and dissimilarity in surface roughness. The marketing demands have caused improvement in implant design. According to marketing demands, the design of dental implants has concentrated on modification of shape, size, material, and surface topography of primary designs. Since the introduction of osseointegrated dental implants, the popularity of these implants has been increased, however, time dependant bone resorption is inevitable. Implant design controls the stress concentration at the bone-implant interface and shapes bone biological response. The growth of the roughness of the implant surface causes an increase in the contact area and a reduction in stress and strain level in the vicinity of the implant. The magnitude of strains in the bony area surrounding the implant must be kept within physiological levels to preserve bone mass. At present, dental implants in the market are made of metal alloys covered by biocompatible surface coating to enhance osseointegration and the healing process. Since the integration of bone-implant has been highlighted in dentistry investigations, improving implant design depends on the prediction of mechanical reactions and remodeling response of bony tissues around implants
+Dental implants are used to replace partial or fully edentulous patients. The dental implant industry will probably produce screw-shaped implants with different thread configurations and dissimilarity in surface roughness. The marketing demands have caused improvement in implant design. According to marketing demands, the design of dental implants has concentrated on modification of shape, size, material, and surface topography of primary designs. Since the introduction of osseointegrated dental implants, the popularity of these implants has been increased, however, time dependant bone resorption is inevitable. Implant design controls the stress concentration at the bone-implant interface and shapes bone biological response. The growth of the roughness of the implant surface causes an increase in the contact area and a reduction in stress and strain level in the vicinity of the implant. The magnitude of strains in the bony area surrounding the implant must be kept within physiological levels to preserve bone mass. At present, dental implants in the market are made of metal alloys covered by biocompatible surface coating to enhance osseointegration and the healing process. Since the integration of bone-implant has been highlighted in dentistry investigations, improving implant design depends on the prediction of mechanical reactions and remodeling response of bony tissues around implants.
 ==Acknowledgement==

@@ Line 149: / Line 149: @@
 {| style="text-align: center; border: 1px solid #BBB; margin: 1em auto; width: auto;max-width: auto;"
 |-
-|style="padding:10px;"| [[File:Review_594900599680_4372_Untitled.jpg|200px]]
+|style="padding:10px;"| [[File:Review_594900599680_4372_Untitled.jpg|400px]]
 |- style="text-align: center; font-size: 75%;"
 | colspan="1" style="padding:10px;"| '''Figure 7'''. Different implant–abutment attachment methods [42]

@@ Line 142: / Line 142: @@
 In a study by Cehreli et al. on Branemark, ITI, and Astra Tech dental implants, compressive and tensile strain under vertical and oblique loads of 100 and 150 N were measured [1]. According to Saint Venant’s principle, when the load distribution at the end of a structure is changing while the resultant load is constant, only the stress magnitudes in the adjacent area close to the end will change. Therefore, the position and amount of stresses in the marginal bone surrounding the implant are essential. Consequently, conical designs demonstrated lower stress magnitudes than cylindrical designs according to finite element results. He reported insignificant differences between cylindrical and conical implants under 100 N and 150 N loads for Astra Tech, Branemark, and ITI. However, these results approve an even slightly better distribution of strain and stress for conical shapes compared to cylindrical ones with the same geometrical characteristics [1,2].The study of Hsu et al. exhibited a linear relationship between mineral bone density with pullout strength and insertion torque [34]. The higher the bone density, the more significantly higher pullout and insertion torque for conical shape implants. Tapered design implants in denser bone compared to straight cylindrical implants could better compact the bone in the insertion process and show higher maximal pullout strength. The obtained results demonstrate that the maximal insertion torque is related to the pullout strength [34]. Rieger et al. conducted a finite element study on conical shape dental implants. Based on his findings, the conical shape implants with high elastic modulus are the most suitable choice for singular implants [40]. It was concluded that tapered design dental implants with a high module of elasticity are the most appropriate implants; however, to avoid bone resorption the design must be in a way to reduce the peak stress concentration in the implant neck. In another study, Rieger et al. concluded that tapered dental implants are a better choice than cylindrical implants in case of punching stresses [41]. He reported that truncated retentive elements such as fins, threads, or serrations are a better choice than the un-truncated ones.
-==3.2       Abutment and Crown==
+===3.2 Abutment and crown===
-A dental implant consists of an implant root that is placed into the jawbone; an abutment that connects the dental prosthesis to the main body once the implant is osseointegrated successfully with the bone. The implant abutment connection could be a screw or clamped mechanism that depends on the design structure. There are two types of implant-abutment mating systems; screw system and tapered-interface fit which is also called Morse taper. In Fig. 7, different abutment systems of commercial dental implants are displayed. Branemark and Astra implant systems have screw-type mating, Ankylos and ITI use a screw with a tapered ending system, and Bicon only uses tapered-interface fit [42].
+A dental implant consists of an implant root that is placed into the jawbone; an abutment that connects the dental prosthesis to the main body once the implant is osseointegrated successfully with the bone. The implant abutment connection could be a screw or clamped mechanism that depends on the design structure. There are two types of implant-abutment mating systems; screw system and tapered-interface fit which is also called Morse taper. In [[#img-7|Figure 7]], different abutment systems of commercial dental implants are displayed. Branemark and Astra implant systems have screw-type mating, Ankylos and ITI use a screw with a tapered ending system, and Bicon only uses tapered-interface fit [42].
-<div class="center" style="width: auto; margin-left: auto; margin-right: auto;">
+<div id='img-7'></div>
-[[File:Review_594900599680_4372_Untitled.jpg]] </div>
+{| style="text-align: center; border: 1px solid #BBB; margin: 1em auto; width: auto;max-width: auto;"
+|-
-<div class="center" style="width: auto; margin-left: auto; margin-right: auto;">
+|style="padding:10px;"| [[File:Review_594900599680_4372_Untitled.jpg]]
-'''Fig. 7.''' '' ''Different implant–abutment attachment methods [42]'''</div>
+|- style="text-align: center; font-size: 75%;"
@@ Line 158: / Line 160: @@
 Friction and lock mechanism are the principal factors in the Morse taper abutment connection. In the screw mating system, abutment threads are responsible to secure the connection under occlusal forces. However, in the interface fit system, masticatory loads are tolerated by the tapered design of the mating system to keep the abutment balanced. High normal stress is expected over the contact area of a tapered interface fit system that stabilizes the implant abutment position by the use of friction. In a screw-type mating system, a compressive force is applied to tighten the abutment screw and make a contact between implant abutment threads' surface. Abutment stretch capacity, tightening load, and maintenance of the tightening preload are the determinant factors in screw joint success. Screw loosening and low tightening preload would threaten joint stability and yield to clinical failure. The most important reasons for joint unsteadiness are insufficient preload, unsatisfactory screw design, weak element fit, poor surface roughness, disproportionate loading, and bone elasticity. Because of the tapered interface fit characteristic, occlusal forces perform in appropriate direction that keeps the abutment and secures the connection, so screw loosening is not a complication. Any external pullout force which is smaller than tightening preload would increase the tensile stress and decrease the compressive stresses on the implant. To reach this balance in the screw joint, the tightening preload must be kept within a limited amount that does not allow the joint to open up.
 ==Conclusion==