|Year : 2014 | Volume
| Issue : 2 | Page : 114-117
Improving esthetics of finger prosthesis by glove silicone
Laxman Singh Kaira1, Esha Dabral2
1 Department of Dentistry, Veer Chandra Singh Garhwali Government Medical Sciences and Research Institute, Pauri Garhwal, Uttarakhand, India
2 Private Practionner, Ram Chanda Oro Dental Clinic, Srinagar, Pauri Garhwal, Uttarakhand, India
|Date of Web Publication||16-Oct-2014|
Laxman Singh Kaira
Type 2, House No. 4, Block No. 2, Faculty Residence, Veer Chandra Singh Garhwali Government Medical Sciences and Research Institute Campus, Srinagar, Pauri Garhwal, Uttarakhand
Source of Support: None, Conflict of Interest: None
Finger and partial finger amputations are some of the most frequently encountered forms of partial hand loss. A high quality esthetic prosthesis with passive function can be helpful to the patient since loss or congenital absence or malformation have both a social and psychological impact on the patient. Prosthetics is an art and science, which provides lifelike appearance to the lost structures of the patient. This case report presents the fabrication of a silicone finger prosthesis, which had good suspension, adequate function, was comfortable to use and esthetically acceptable to the patient.
Keywords: Glove type silicone finger prosthesis, partial finger amputation, prosthetic finger
|How to cite this article:|
Kaira LS, Dabral E. Improving esthetics of finger prosthesis by glove silicone
. J Orofac Sci 2014;6:114-7
| Introduction|| |
Finger and partial finger amputations are some of the most frequently encountered forms of partial hand loss. The most common causes of these amputations are trauma, congenital absence, and malformations.  In India, a developing country where farming is the main occupation, most of the partial traumatic finger amputations are seen in the harvesting season. Primitive agricultural machines such as Kutty and the thresher machine take a heavy toll on hands of young men and women every year.  Any deformity, especially with the hands, which are constantly in the view of the patient and others, may adversely affect a patient's socio-economic status.  Advances in surgical sciences in the form of microvascular re-implantations have helped save many severely injured and traumatically amputated digits. However, in most of the patients, microvascular reconstruction is contraindicated, unavailable or unsuccessful. It is in this group of patients that a prosthesis can be provided and may offer great help as, besides psychosocial issues, patients also face pain, contractures, reduced grip strength, and hypersensitivity. 
The fabrication of the prosthesis is as much an art as it is a science. Prosthesis form, coloration, and texture must be as indiscernible as possible from the surrounding natural tissues.  Rehabilitation efforts can only be successful when the patient can appear in public without fear of attracting unwanted attention. , This paper presents the prosthetic rehabilitation of amputated fingers with a custom-made prosthesis fabricated using silicone elastomers, which had adequate suspension, function, is comfortable to use and esthetically acceptable to the patient.
| Case report|| |
A 32-year-old male patient reported to the outpatient department, for the fabrication of finger prostheses. On general examination, it was noticed that the patient had lost part of his middle finger of the left arm due to trauma in a thresher machine. Amputations were carried out through the distal portion of the middle inter phalanx of the middle finger. The amputated fingers showed thickened ends [Figure 1]. The surrounding area appeared to be normal with no signs of any infection over the digits. After taking informed consent from the patient, to ensure his willingness and cooperation, the case was taken up for reconstruction of partially missing finger of the left hand. As the patient concerned was self-motivated, the role of the psychologist was found to be minimal in this case.
The rehabilitation was done in close collaboration with the physiotherapist. Approval of the Ethics Committee was obtained.
The patient's left hand was lubricated with a thin layer of petroleum jelly to prevent adherence of impression material to the skin and hair. The area around the hand was boxed, and impression material, irreversible hydrocolloid (Alginate, Zelgan 2002, Dentsply, India; Batch No. Z090218) was placed over the palmar side first and then the dorsal side to prevent tearing and distortion of the material. This technique also allows the hand to be removed from the impression with the fingers inflexion.  The patient was instructed to keep a hand in the normal resting position without stretching. An impression was then poured in stone plaster, Type III (Gold Stone, Asian Chemicals, India; Batch No. 309251/25), and a positive replica of the hand was retrieved. A donor whose finger dimensions and contours closely mimicked the fingers of the patient was chosen to reduce the time required for sculpting. A putty impression (Aquasil Putty, Dentsply, Germany; Batch No. 0811003044) was made. Wax was then poured into the putty index and retrieved. The wax pattern was then hollowed from the inside by sculpting. The wax patterns were then placed on the cast and modifications in sculpting were carried out to resemble the digits of the other hand. The wax pattern was then tried on the patient's hand [Figure 2]. The wax patterns were relined with light body impression material (Reprosil, Dentsply, Germany, DE 19963-0359) to achieve a better fit. This was then poured in stone plaster, Type III (Gold Stone, Asian Chemicals, India; Batch No. 309251/25). An indexed base was then made.
Stump model preparation
Since the prostheses were meant to be a "glove"-like construction, it was essential to ensure a snug fit of the silicone to the tissue. In order to provide a snug prosthetics fit, the stump was reduced accurately by around 0.5-1 mm, so that silicone stretches and flexes over the stumps as prostheses were fit.
Each stump with a keyed base and wax pattern was then invested in a Hanau Flask. The first pour was done until the junction of dorsal and ventral surface. Separating medium was then applied, and a second pour was done to cover the entire wax pattern. Dewaxing was carried out, and the flask was allowed to cool [Figure 3]. A two-piece mold was thus obtained. The advantage of this technique is that it eliminates the unsightly voids in the prosthesis commonly seen while using silicone, as it is more viscous and does not flow easily into inaccessible areas. It also facilitates color matching so that the under surface of the fingers can be matched first with a lighter shade and packed. Next the stump is inserted in place and the color on the dorsal surface, usually a darker shade, is matched and the packing is done. Factor II Brand medical grade silicone MDX-4210 room temperature vulcanizer (RTV), better known as Dow Corning Brand silicone, was used. The base color was dispensed [Figure 4] and intrinsic colors were mixed to achieve the required shade. The shade matching was carried out in natural light between 11:00 and 13:00 h [Figure 5] and [Figure 6]. The patient's presence was critical to gain his approval. Escape vents were provided to prevent air entrapment and for escape of excess material. The material was allowed to bench cure overnight. Once the final prosthesis was retrieved, the flash was trimmed using a sharp blade and final finishing was accomplished using a silicone burs. To complete the prosthesis, an artificial nail was fabricated with cold cure clear acrylic resin layered on a pink cold cure acrylic resin (Dentsply, Rapid Recovery Powder; Batch No. R080610). The nail was carefully fashioned to match those of the corresponding normal hand. A cyanoacrylate adhesive was then applied on the under surface of the nail for bonding with a silicone surface to achieve a realistic appearance.
The final step was placement of the prosthesis on the patient's hand in lieu of the missing finger. Since the prosthesis was extended up to the metacarpal-phalangeal joint, the patient was asked to wear a finger ring to mask the junction. The patient was instructed and demonstrated about the use and maintenance of the prosthesis.
| Results|| |
The patient was satisfied with the esthetics and was also able to resume functioning by holding light objects.
| Discussion|| |
The loss of even one finger produces significant deficiencies. The more dexterous individuals suffer the greatest degree of impairment. Prosthesis can often restore near normal function in distal phalange amputations. When part of the hand and two or more fingers have been amputated, requests are often made for a complete glove covering. Although this may be supplied, it must be appreciated that the surviving digits are unlikely be comfortable. Function of the intact portion of the hand will inevitably suffer while it is encased. Sweating is also a troublesome feature. ,,, Silicone finger restorations may have additional functional benefits.
Silicones unlike polyvinyl chloride prosthesis allow copying of the natural hand in every detail,  the material is supple and not subject to ordinary thermal damage or ink stains. Thinness of the silicone prosthesis allows good sensibility through it.  Many traumatic amputees experience painful hypersensitivity at the termination of finger remnants. They also improve the hydration of stratum corneum of immature hypertrophic scars.  Prosthetic rehabilitation is quick, medically uncompromised and allows the surgical site to be closely monitored.  Creating a prosthesis that appears to have a realistic skin surface, while achieving seamless visual integration with the surrounding tissue requires both artistic and technical expertise. The skin of the hand also changes color, not only by exposure to sunlight but also in response to elevation or dependency.  Placing a decorative ring over the margin of a finger prosthesis ending at metacarpal-phalangeal joint will make changing color of the handless noticeable although the distal joint functions will be slightly restricted.  Medical grade Silicone was used for the fabrication of the prosthesis. The MDX-4210 is an RTV and does not shrink on curing. This translucent silicone is compatible with all the intrinsic and extrinsic coloring systems available.  Significant advances in the field of material science have led to the production of new silicones with improved characteristics and improved methods of prosthesis coloration. 
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[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6]