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ORIGINAL ARTICLE |
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Year : 2012 | Volume
: 2
| Issue : 1 | Page : 30-34 |
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Comparative evaluation of fluid absorbancy of retraction cords of different thickness after various medicament immersions
Shushant K Garg, Sandeep Garg, Sanjeev Mittal, Sangeeta Goyal
Department of Prosthodontics, Maharishi Markandeshwar College of Dental Sciences and Research, Mullana, Ambala, Haryana, India
Date of Web Publication | 22-Mar-2012 |
Correspondence Address: Shushant K Garg Department of Prosthodontics, Maharishi Markandeshwar College of Dental Sciences and Research, Mullana, Ambala, Haryana India
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/2229-5194.94189
Abstract | | |
Purpose: To evaluate fluid absorbancy of retraction cords of different thickness after various medicament immersions. Materials and Methods: Ultrapak retraction cords of three different thicknesses (No. 000, 00, 0) with identical lengths (25 mm) were used. They were immersed in two different medicaments (25% aluminum chloride and saturated alum) for 20 min. Two different immersion fluids (artificial saliva and human plasma) were compared for fluid absorbancy. The capability of the cords to absorb fluids was measured by a gravimetric method. The data were analyzed by F test analysis and P<.05 was regarded as significant. Results: Regardless of the medicament used and immersion fluid, a relationship existed between cord thickness and the amount of fluid absorbed. There was a significant difference in the fluid absorbancy of all the three groups (P<0.01). A significant difference was also observed in the fluid absorbancy of saliva and plasma (P<0.05). Conclusion: The results of this study indicated that fluid absorbancy increased in linear proportion to the increase in thickness of the retraction cord. Ultrapak (#0) when treated with alum showed most favorable results. All the cords absorbed artificial saliva more than plasma irrespective of cord thickness and medicament used. Keywords: Immersion fluid, medicaments, plasma, retraction cord
How to cite this article: Garg SK, Garg S, Mittal S, Goyal S. Comparative evaluation of fluid absorbancy of retraction cords of different thickness after various medicament immersions. J Interdiscip Dentistry 2012;2:30-4 |
How to cite this URL: Garg SK, Garg S, Mittal S, Goyal S. Comparative evaluation of fluid absorbancy of retraction cords of different thickness after various medicament immersions. J Interdiscip Dentistry [serial online] 2012 [cited 2023 May 29];2:30-4. Available from: https://www.jidonline.com/text.asp?2012/2/1/30/94189 |
Introduction | |  |
The success of fixed prosthodontic restoration is largely dependent upon the long-term health and stability of the surrounding periodontal structures. Marginal integrity is one of the basic criteria of the principles of tooth preparation. Margins are one of the most important and weakest links in the success of restorations, and are also referred to as the 'gingival finish line'. [1] There are three types of gingival finish lines according to the location of the marginal placement: Supra-gingival, Equi-gingival, Sub-gingival. [2] Supra-gingival and equi-gingival margins exert less impact on the health of abutment teeth as compared to the sub-gingival margin. A sub-gingival margin poses difficulty in recording the finish line during impression procedure, finishing of the restoration and maintenance of abutment teeth health. So the gingival tissue must be dilated vertically and horizontally to allow sufficient impression material to be injected in to the dilated gingival tissue to record the subgingival margin accurately.
Various techniques and methods have been used to manage the gingival tissues. According to Bensen et al., [3] they include: (1) Mechanical methods, (2) Mechanico-chemical methods, (3) Rotary gingival curettage (Gingitage), and (4) Electrosurgery. Of these four categories, the mechanico-chemical method of gingival retraction is the most widely used, as was found in a survey by Donovan et al. [4] The mechanical aspect of this method involves placement of a string into the gingival sulcus to displace the tissues physically. The chemical aspect of the method involves treatment of the string with one or more compounds that will induce temporary shrinkage of the tissues and should also control the hemorrhage and fluid seepage that often accompany subgingival margin preparation.
Many different medicaments have been used or suggested for gingival retraction procedures. These include epinephrine, aluminum chloride (AlCl 3 ), aluminum sulfate, zinc chloride, alum (aluminum potassium sulfate), ferric sulfate, and ferric sub sulfate. [5],[6]
It has been demonstrated that retraction cords with no medicaments were less suitable for hemostatic purposes than those impregnated with aluminum sulfate or epinephrine. Runyan et al., [7] observed that soaking the retraction cord in an AlCl 3 solution before placing it in gingival sulci provides hemostasis but does not lessen the cord's ability to absorb crevicular fluid. Camargo et al., [8] observed that hemostatic solutions absorbed by retraction cords did not alter the polymerization and accuracy of dental impression materials; other investigators have found that some retraction cord medicaments {AlCl 3 , ferric sulfate [Fe 2 (SO 4 ) 3 ], ferric subsulfate [Fe 4 (OH) 2 (SO 4 ) 5 ]} can modify the surface detail reproduction. Therefore careful removal of all traces of these medicaments before recording the vinyl polysiloxane impression has been recommended.
It is evident that the amount of medicament solution absorbed by cords during soaking is of importance to achieve a proper haemostatic action. In the previous studies an inverse relation was found between the thickness of the cord and the rate of haemostatic fluid uptake. [9]
However one major factor has never been taken into consideration in the previous studies. As we know blood and saliva both are present in the gingival sulcus around the prepared tooth. It is very important to create a clear field without any fluid around the prepared tooth for maximum detail reproduction before making an impression. But the capability of the retraction cord to absorb either blood or saliva more has never been assessed earlier. This factor was taken into consideration in the present study.
It is in the light of this background that the present study attempts to evaluate the effect of various medicament treatments and thickness of retraction cords on fluid absorbancy.
Materials and Methods | |  |
Plain retraction cords of three different thicknesses i.e. No. 0, 00, and 000 (Ultrapak, Ultradent Products, South Jordan, Utah, USA) [Figure 1] were selected for the study. Each type of cord was cut into 30 pieces (n=30) having an identical length of 25 mm. 10 pieces of each cord were left untreated/dry (I). Two different solutions were tested as retraction cord medicaments i.e. saturated Alum (II) (NICE Chemicals Pvt Ltd) and 25% Aluminum chloride (III) (NICE Chemicals Pvt. Ltd). Thus, the three different thickness cords, based on the two tested solutions, were divided into groups as shown in [Table 1] with each group having 10 pieces of each cord (n=10) [Figure 2]. The 10 pieces of each group were further divided into two sub-groups (n=5) according to two different immersion fluids used, i.e. human plasma (contains proteins similar to gingival crevicular fluid) and artificial saliva (simulate in vivo environment) [Table 1].  | Table 1: Distribution of the three retraction cord in different groups and sub-groups
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The amount of the absorbed fluid was determined by the gravimetric system with an electronic analytical balance (ICPA Health Products Ltd., India) [Figure 3], by subtracting the weight value of the sample measured before immersion from the weight value measured at the end of immersion.
To begin with the thirty samples of Group I0, I00, and I000 were left untreated and their dry weight was recorded.
Then thirty samples of II0, II00, II000 were immersed in saturated alum solution and the thirty samples of III0, III00, III000 were immersed in 25% aluminum chloride solution for 20 min and the samples were taken out. The excess fluid accumulating on the outer surface of the samples was removed by filter paper saturated in the corresponding test solution held between the thumb and index finger. [9] Their initial wet weight was recorded.
Following this, five cords out from each group was immersed in plasma solution and the remaining five in artificial saliva for 10 min. The samples were taken out of immersion fluids and the excess fluid accumulating on the outer surface of the samples was removed by filter paper. The piece of cord was weighed again by the gravimetric method to obtain the final wet weight value.
Fluid absorbancy
Final wet weight - Dry weight
The amount of fluid absorbed by the 60 samples of saturated alum and 25% aluminum chloride was calculated by subtracting the initial wet weight value of the sample from the final wet weight value. The amount of fluid absorbed by untreated/dry samples was calculated by subtracting the dry weight value of the sample from the final wet weight value.
Results | |  |
Values for fluid uptake by cords of various thicknesses and in different test solutions were plotted in a linear coordinate system as a function of thickness and the best-fit line was constructed. The data were analyzed by F test analysis and P <0.05 was regarded as significant [Table 2]. | Table 2: Statistical comparison of groups for fluid absorbancy by repeated measures of analysis of variance (ANOVA)
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There was a significant difference in the fluid absorbancy of all the three groups. The results of the kinetic investigations obtained for different cords are presented in [Figure 4] and [Figure 5]. A relationship existed between cord thickness and amount of fluid absorbed. Regardless of the tested medicament and immersion fluid used, with the decrease in cord thickness the amount of fluid absorbed decreased significantly (P <0.001). Cord No.0 showed the maximum fluid absorbancy and Cord No.000 showed minimum fluid absorbancy among all the Groups and Subgroups. Samples immersed in saturated alum showed a statistically significant greater fluid absorbancy as compared to those left untreated/dry and those immersed in 25% aluminum chloride (P <0.05). Samples immersed in 25% aluminum chloride showed a similar fluid absorbancy as the untreated dry samples. Samples soaked in artificial saliva showed more fluid absorbancy than samples soaked in plasma in all groups with a statistically significant difference (P <0.05). | Figure 4: Comparing Mean Values of fluid absorbancy of all the Groups soaked in plasma when kept untreated, treated with alum and treated with AlCl3
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 | Figure 5: Comparing Mean Values of fluid absorbancy of all the Groups soaked in artificial saliva when kept untreated, treated with alum and treated with AlCl3
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Discussion | |  |
The aim of gingival retraction is to allow access for the impression material beyond the abutment margins and to create space for the impression material to be sufficiently thick. Tear resistance of the impression material can be affected by the thickness of the material. The present study was conducted for determining the fluid absorbancy of retraction cords of varying thickness immersed in different medicament solutions.
Ultrapak retraction cord was chosen because it has chain-like construction of interlocking loops which lets the cord bend passively in any direction. Ultrapak cord's interlocking loops can carry approximately 2.5 times more haemostatic solution than conventional cords. [10] Retraction cords of three different thicknesses (No. 0, 00, and 000) by the same manufacturer were used to find out the effect of cord diameter on the fluid absorbancy which may be directly or indirectly related to each other. The increase in the diameter of the cord may increase the fluid absorbancy and provide adequate space for the impression material. Till now no such study had been done to support this relationship.
All the samples were of the same length, i.e. 25 mm, which is in accordance with the study done by Runyan et al., [7] Their study used 10 cords each (n=10) of seven different types of retraction cords, 25 mm in length, to check fluid absorbency after soaking in aluminum chloride solution. [7] In our study two different immersion fluids were chosen due to the fact that both blood and saliva are present in the gingival sulcus during retraction procedures which should be properly cleared off for making an ideal impression. Due to hemorrhage caused while placement of gingival retraction cord there is presence of blood and gingival crevicular fluid. So to simulate this in-vitro human plasma was chosen in the present study as plasma contains proteins similar to crevicular fluid and blood. To simulate saliva in vitro artificial saliva was taken.
Two medicaments, i.e. 100% alum and 25% AlCl 3 were selected for this study as both are astringents that cause precipitation of tissue proteins and vasoconstriction. [11] According to a survey by Donavan et al., [4] equally effective astringent gingival deflection agents such as alum and aluminum chloride exert no systemic effects.
This study was standardized by using all retraction cords by the same manufacturer (ULTRAPAK), cut into samples of identical length (25 mm), soaked in medicament for the same time period (20 min) and soaked in fluids, i.e. plasma and artificial saliva for the same time period (10 min).
The results of the present study showed that samples prepared from the thickest retraction cords by the same manufacturer have better fluid absorbancy than the samples prepared from thinner cords irrespective of the medicament used. That is the amount of fluid absorbed increases in linear proportion with the size of the cord.
All the previous studies evaluated the rate of fluid uptake of the haemostatic solution. But the present study measured the amount of fluid absorbed from the gingival sulcus when similar conditions were created in vitro.
The results of the present study showed that samples treated with alum had greater fluid absorbancy and the AlCl 3 solution had similar fluid absorbancy as the untreated cords, which means that soaking the retraction cords in a haemostatic solution (alum and AlCl 3 ) does not decrease the ability of the cord to absorb fluid which is present around the gingival sulcus.
One major factor which was always ignored in the previous studies was that whether the retraction cords will soak plasma more or saliva which is a must for better visualization of the margins of the prepared tooth for better detail reproduction. The results of the present study revealed that samples soaked in artificial saliva exhibited more fluid absorbancy than the samples which were soaked in plasma irrespective of the cord thickness. This can be attributed to the more complex composition of human plasma containing dissolved proteins, glucose, clotting factors, mineral ions, and hormones which may make it more viscous and difficult to get absorbed as compared to saliva.
The only limitation of the study was that it was an in vitro study. The conditions created could not completely simulate those in the oral cavity. Doors of enlightenment and improvement are always open; therefore there is scope for future investigation in the field. This could be in regard to different types of retraction cords by different manufacturers, various other medicaments and a variety of combinations with the same and different thickness of retraction cords.
Conclusion | |  |
The thickness of retraction cords was a crucial factor in the successful gingival retraction procedure. Thicker cords (No. 0) showed maximum fluid absorbancy irrespective of the medicament used and immersion fluid. Saturated alum and 25% aluminum chloride can be safely used as retraction medicaments as they do not decrease the ability of the cord to absorb fluid which is present around the gingival sulcus. Retraction cords treated with saturated alum solution had maximum fluid absorbancy for both plasma and artificial saliva. All the retraction cords had greater ability to absorb saliva than the crevicular fluid which can be attributed to its greater viscosity.
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[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5]
[Table 1], [Table 2]
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