The eye was a symbol of life to the

ancient world, particularly in Egypt,

where bronze and precious stone eyes

were placed on the deceased.

The Romans decorated statues with

artificial eyes made of silver.

history

Ambrose Paré (1510-1590), a famous French surgeon, was the first to describe the use of artificial eyes to fit an eye socket. These pieces were made of gold and silver.

Enamel prostheses (1820s-1890s)

were attractive but were expensive

and not very durable.

The introduction of cryolite glass,

made of arsenic oxide and cryolite

from sodium-aluminum fluoride

(Na6A2F12), produced a grayish-

white color suitable for a prosthetic

eye.German craftsmen are credited

with this invention in 1835.

To make these glass eyes, a tube of glass was heated

on one end until the form of a ball was obtained.

Various colors of glass were used like paintbrushes to

imitate the natural color of the eye

The glass art form flourished in France and Germany

where fabricating secrets were handed down from one

generation to the next.

The town of Lausche, Germany, had a

particularly rich history in both decorative (doll

eyes, Christmas ornaments) and prosthetic arts.

In the 19th century, German craftsmen

("ocularists") began to tour the United States

and other parts of the world, fabricated eyes

and fit them to patients.

Stock eyes (or pre-made eyes)

were also utilized. An "eye

doctor" might keep hundreds of

glass stock eyes in cabinets, and

would fit patients with the best

eye right out of the drawer.

In the United States, eyes continued to be made of

glass until the onset of World War II, when German

goods were limited and German glass blowers no

longer toured the United States.

The United States military, along with a few private

practitioners, developed a technique of fabricating

prostheses using oil pigments and plastics. Since World

War II, plastic has become the preferred material for

the artificial eye in the United States.

By the mid-1940s, glass eyes were

being replaced by plastic counterparts.

In Virginia, this was led by Joseph

Galeski

(of Richmond, Virginia),

Although American Optical and several

military hospitals started to experiment

and dispense plastic artificial eyes.

An ocular implant replaces the lost

volume of the natural eye. The first

account of placing an implant in the

socket, following enucleation, was

in 1841.

Implants have been made of many

different materials, shapes, and

types throughout the years. It also

helps the artificial eye to have some

degree of movement

Naval dental school (1940), tested the use of acrylic resin in fabricating a custom ocular prosthesis. Unlike a glass eye, an acrylic eye was easy to fit and adjust, unbreakable, inert to ocular fluids, esthetical good,

longer lasting and easier to fabricate

Surgical procedures in the removal of an eye are classified into three categories

Evisceration- Removal of the contents of the globe, but leaving the sclera and sometimes the cornea in place. Because the extra-ocular muscles are left intact, good mobility of the prosthesis is usually possible

Enucleation- Removal of the eyeball itself Exenteration- Removal of the entire contents

of the orbit, including the extraocular muscles

Stock ocular prosthesis

Stock acrylic resin eyes are supplied in three basic shapes: oval, standard and three-cornered.

Each shape has three sizes: small, medium and large, and they may be prepared for the right or the left eye.

The irises are produced in three basic colours: brown, hazel and blue, and the individual colours have been formulated so that they have some elasticity and overlapping quality in matching effects.

The scleral colours are also varied.

One basic size of iris (11.5 mm) is used, and it has a pupil opening of 3.5 mm.

Where possible, the stock eye should be made to duplicate as closely as possible the superior fit and aesthetics of the custom eye.

impressions

Dental impression materials such as impression compound, dental waxes, irreversible hydrocolloids ,tissue conditioners and elastomeric materials have been successfully used to register the topography of the eye socket

Stock tray impression technique:

• An impression is made of the ocular defect using a

disposable syringe, stock ocular trays and irreversible

hydrocolloid.

•Stock acrylic resin impression trays available in

different sizes for ophthalmic impressions

•Trays have a hollow handle which accomodates an

impression syringe

During the procedure ,the patient should be seated in an upright position with the head tilted backward at app 450 This position allows the natural positioning of the palpebrae and surrounding tissue relative to the force of gravity.

The tray should be placed into the defect to determine the proper orientation and fit without overextension.

The tray is then removed and the impression material is loaded in the syringe and sufficient material is ejected to fill the concavity of the tray.

Ophthalmic irreversible hydroclloid is mixed in a 30 ml medicine cup –app 5 ml of powder to 5 cc of room temp water.

Alginate – warm ,runny mix flow easily not distort the fatty tissues in the socket

The tray is reinserted and sufficient material is injected to elevate the lid contours similar to the normal side.

once filled the patient is directed to move their eyes both up and done.

After the impression sets the assembly is removed and examined for defects and voids.

L. M. Sykes,Essop, Veres(J Prosthet Dent 1999;82:362-5.)

described a procedure for fabricating acrylic resin ocular custom-made conformers to maintain socketsize and contour.

These custom-made ocular conformers act as an interim measure and as valuable diagnostic indicators of problems experienced by the patients..

While stock conformers merely maintain the socket size and prevent scar tissue contractures, the custom-made conformers can also be used to enlarge unfavorably small sockets, stimulate eyelid movement, aid hygiene, help the clinician develop the final shape for the definitive prosthesis, and reduce the amount of postinsertion adjustments needed.

If further surgery is needed to deepen the socket bed or alter the eyelids, the socket is enhanced by using the conformer as a surgical stent to maintain the mucosal grafts in position and support the fornices.

Early settling and sinking occurs with most patients, so that modifications to their conformers are required to maintain an esthetic appearance and adequate eyelid support.

These advantages and the ease of fabrication make custom-made conformers a viable initial treatment option in patients with ocular defects

The presence of the custom-made conformer and its close approximation to the tissues in the socket, stimulates the eyelid muscles to move, thus,exercising them and preventing disuse atrophy.

Stock conformers lack a close fit and therefore cannot stimulate eyelid movement

Beumer et al advocated placing a plastic stock conformer immediately into the socket to fit the contours of the cavity and to fill the depths of the fornices.

These were to be left in place while healing occurs to reduce edema and to maintain the socket contours for the definitive prosthesis

Anesthetize the socket with 1 or 2 drops of topical anesthetic

Select an ocular special tray of the appropriate size and try it into the socket to verify the fit.

If the special tray is not available, a tray can be fabricated at the chairside by heating a small piece of modeling compound and adapting it to the area around the eye or around a small rubber ball.

This should be kept as thin as possible [2 to 3 mm].)

Place a small tube in the center of the compound and lute it into position with sticky wax.

The addition of a few small holes in the wax aids retention of the impression material.

Hydrocolloid material is mixed to a runny consistency by adding 1.5 parts warm water to 1 part powder.

Inject the hydrocolloid down the tube into the socket under slight pressure while supporting the tray in position, then allow the impression to set.

Remove the impression and use it to pour a 2-piece split cast mold that is used to fabricate the acrylic resin conformer.

Once fabricated, the conformer can be fitted immediately and adjusted at the chairside where needed, thus not allowing time for the socket to shrink and scar tissues to contract.

Dismiss the patient with instructions to wear the conformer continuously and only to be removed for cleaning.

Severe pain or discomfort must be reported immediately to ensure that necessary adjustments can be made.

Once the clinician and patient are satisfied with the size and conformity of the conformer, and the socket is well healed and dimensionally stable, a conventional, definitive ocular prosthesis can be manufactured.

A duplicate of the modified conformer in wax can be used as a template for the definitive prosthesis

Alginate impression material is expressed into the defect using a disposable syringe.

Next a perforated acrylic resin tray is loaded and placed over the defect.

The impression is first recovered from the lower, shallower sulcus first, then rotated out of the deeper, upper sulcus.

38

External tray impression technique(Taylor)

The impression is boxed and poured in the dental stone up to the height of contour of the impression.

A separating agent is placed and the reminder of the impression is poured

Engelmier.R.L.Autoclavable custom made metal impression trays to improve infection control.JPD 1987;58:121-2

Has suggested casting a set of stock trays in ticonium which is a non precious,removable partial denture alloy (Ticonium Co ,Albany,NY) which can be sterilized in an autoclave for reuse

The impression material of choice is ophthalmic alginate(Ophthalmic Moldite)

Ow,Amrith.Use of a tissue conditioner material to modify a stock ocular prosthesis.JPD 1997;78:218-22

Advocated the use of tissue conditioners as a reline material because of its bio compatibilty and ease of manipulation.

Stock acrylic resin prosthesis is selected and is modified by trimming its periphery to fit the eye socket Visogel(Dentsply,England) is added and inserted for 20 mins.

Excess material is removed and the ocular prosthesis is worn for 24-48 hrs

If the esthetics and adaptation are acceptable ,the prosthesis is relined with heat cure resin.

Smith R M.Relining an ocular prosthesis-A case report.JPD 1995;4:160-3

Described a reline procedure for an existing ocular prosthesis

The ocular prosthesis is reduced in size until it fit comfortably in the socket.

Melted base plate wax is added to the borders until the ocular prosthesis is positioned properly

Borders of modified prosthesis are shaped with baseplate wax until proper gaze is establishcd

The lid contours and gaze were assessed and wax carved or added until the position of the ocular prosthesis was satisfactory in all dimensions

Ocular prosthesis in place after borders are adjusted, and gaze is established.

A thin layer of Korrecta wax No.4 is added to the intaglio surface and the borders

The prosthesis is then dipped into 123 0 F water bath,inserted and left for 5 mins

Ocular prosthesis showing reline impression made with Korecta-wax

During this time, the patient was directed to take the prosthesis through a full range of motion.

The ocular prosthesis was removed, inspected for coverage, and wax added in deficient areas or the excess removed as indicated.

The borders and intaglio surface were covered completely by the Korecta-wax.

If there were any show throughs, the underlying surface was relieved and covered with more wax.

Again, the prosthesis was placed and worn for 5 minutes

Once the dimensions are corrected kept in the patients eyes for 30 mins while he moved it intermittently in all directions

A laboratory reline procedure is then performed .

Ocular prosthesis relined with Crystal Clear acqlic resin.

Impression With Custom Ocular Tray

Miller suggested that a custom ocular tray is necessary in certain situations. For example, the anophthalmic socket could be highly irregular or stock trays may not be available.

Miller BJ: Custom ocular impression trays. J Facial SomatoProsthet 1996;2:109-113

Miller’s method involves attaching a solid suction rod to the patient’s existing prosthesis, conformer, or wax shell and investing it in an alginate mold.

After the alginate sets, the prosthesis, conformer, or wax is removed and replaced with clear acrylic resin.

Perforations are made in the resulting tray, and a tunnel is cut into the stem through which impression material can be delivered.

An impression is made using injected alginate.

Mark F. Mathews, DDS, Rick M. Smith, DDS, Alan J. Sutton, DDS,and Ron Hudson .The Ocular Impression: A Review of the Literature and Presentation of an lternate Technique .JPD December 2000, Volume 9, Number 4

1. The patient’s existing prosthesis or conformer was disinfected and lightly lubricated

2. Medicine cup was filled with

quick set stone (Whip-Mix Blue

Mounting Stone; Whip-

MixCorporation, Louisville,KY),

and the tissue side of the

prosthesis was invested till the

height of contour.

3. When set, the edges of the stone cast were notched. A small amount of PVS putty (Reprosil Putty; DentsplyInternational Inc, Milford, DE),was mixed and was adapted over the top of the prosthesis and into the notched indices.

Putty cope,was removed and a large, beveled sprue hole was cut into its center and a small vent to the side.

4. The prosthesis were removed from the mold, The stone surface was lubricated (Liquid Tin Foil Substitute; Robert B.Scott, Inc, Tampa, FL), and the putty cope was replaced.

5.Chemical-cure polymethylmethacrylate (Great Lakes Co, Chicago, IL),was mixed and poured into the mold .The assembly was placed in a pressure pot for 20 minutes at 25 psi.

6.The acrylic resin tray was removed, trimed and thined as needed.

The tray was perforated approximate at pupil location with a 3- to 4-mm diameter hole.

Multiple perforations were placed over the remainder of the surface.

The custom tray was then polished .

The tray was repolished, and checked for rough spots.

Tray was checked for overextension and proper orientation.

Now the barrel of the 5-mL syringe was attached to the injection tube.

3 teaspoons water and 1 tablespoon of ophthalmic alginate impression material was mixed(Robert B. Scott, Inc), and back loaded in the syringe.

Tray was seated and the alginate was injected. After the alginate impression material was set, the impression was removed and was checked for for acceptability

When set, the alginate mold was removed with impression from the cup.The alginate mold was partially sectioned,and the original impression was retrieved.

The different mixes of alginate will not adhere to each other.

The second alginate impression becomes a mold to form the wax blank. The alginate mold is poured in the cup,with ivory wax (40/40 Ivory Wax; MDLDental Products Inc, Seattle, WA) through the sprue hole created by the syringe tip.

Upon cooling,the impression is removed from the cup to retrieve the wax blan.The sprue is cut off, The wax trial ocular prosthesis is shaped and polished.

Try in of the wax trial prosthesis is done to assess fit, contour, and comfort. The iris button is added to the pattern, and then it is processed.

Formulation of the cast

Imp poured in two sections using a 30 ml cup filled halfway with dental stone .

D.stone is added to the post.surface of the impression and then placed into the cup upto the ant of the postr edge of the imp and allowed to set .

2 keyways are made ,1 each adjacent to the region of the nasal and temporal canthus.

Stone is coated with a seperating medium [tin foil substitute] allowed to dry.

Second half of the mold is poured with dental stone leaving a funnel shaped hole around the stem of the tray .

The hole used as a funnel to fill the mold with molten wax .

After the d.stone has set ,2 halves of the mold are separated and the imp material is removed .

Wax pattern:

The melted wax is then poured through the funnel shaped hole and into the assembled mold.

Soaking the mold in water for a few minutes prior to filling it with molten wax will prevent the wax from adhering to the stone.

After the wax has cooled, the wax pattern is recovered. Once the wax pattern has been smoothed and polished, it is ready to be tried in the eye socket.

To insert the wax pattern, the upper lid is lifted, and the superior edge of the pattern is placed behind the lid and gently pushed upward.

While drawing the lower lid down, the inferior border of the pattern is seated in the inferior fornix, and then the lower lid is released. The eye contours are checked. Pressure points and areas of discomfort is noted and relieved

Iris position

The iris should be bilaterally symmetrical; therefore, accurate placement of the custom-painted iris disk on the scleral wax pattern is critical.

The gaze and the position of the iris is determined .

McArthur RD: Aids for positioning prosthetic eyes in orbitalprosthesis. J Prosthet Dent 1977;37:320-326

McArthur described methods for positioning the artificial eye in the orbital prosthesis using an ocular locator and fixed caliper.

This determined the placement of the prosthetic eye in the mediolateral and supero-inferior planes.

Benson P: The fitting and fabrication of a custom resin artificialeye. J Prosthet Dent 1977;38:532-539

Benson suggested a method for fabricating a Benson suggested a method for fabricating a custom-made acrylic resin ocular prosthesis custom-made acrylic resin ocular prosthesis in which he determined the size and position in which he determined the size and position of the iris by of the iris by visual judgment. visual judgment. Because iris Because iris positioning is a technique-sensitive positioning is a technique-sensitive procedure, visual assessment alone may not procedure, visual assessment alone may not be accurate.be accurate.

Roberts.A.An instrumeny to achieve pupil alignment in eye prosthesis.JPD 22;4:1969

Roberts has suggested the use of a Roberts has suggested the use of a pupillometer pupillometer for precise alignment of the pupil for precise alignment of the pupil in the eye prosthesis. Though the advocated in the eye prosthesis. Though the advocated method may be more precise, it may not be method may be more precise, it may not be feasible to use the pupillometer in every feasible to use the pupillometer in every clinical set-upclinical set-up

The iris should be bilaterally symmetrical;

therefore, accurate placement of the custom-

painted iris disk on the scleral wax pattern is

critical.

Satyabodh S. Guttal, Narendra P. Patil. A Simple Method of Positioning the Iris Disk on aCustom-Made Ocular Prosthesis. A Clinical Report.JOP ;17: (2008) 223–227

The transparent graph grid was used in this method to attach the iris disk.

During the trial of the scleral wax pattern, certain guidelines were marked on the patient’s face with an indelible pencil ,a vertical midline was marked considering the stable anatomical landmarks and prominent points on the face

The midline was marked passing through the forehead crease, glabella, tip of the nose, and chin.

The distance from the right eye medial canthus to the midline and left eye medial canthus to the midline was measured.

This distance standardized the midline marking and was used to reposition the grid template each time during the try-in visit.

The patient was asked to gaze straight at an object kept 4 feet away.

The operator then marked the vertical lines coinciding with the medial and distal extremities of the iris of natural eye.

Similarly, the horizontal lines referring to the center, inferior, and superior limits of the iris were marked.

The facial markings were transferred to the grid template by placing it on the patient’s face.

Markings were also made on the transparent grid template, on the X-axis from A through H starting from the midline, and on the left side A1 to H1; similarly, on the Y-axis from 1 through 7 and 11 to 71.

The distance between each marking was 1 cm on both X and Y axes.

These markings were transposed onto the side of defect. This can be done either directly on the patient’s face or on the facial moulage

The markings were transferred onto the sculpted scleral wax pattern, and the iris button attached to the wax pattern

The method described in this article involves a simple procedure for positioning the iris in a prosthetic eye

The accurate placement of the iris and pupil component in the ocular prosthesis simulated the conversational gaze

Thus, the use of a transparent grid template helped to accurately locate and position the

iris on the custom-made ocular prosthesis rather than relying purely on the visual assessment, the latter being subjective with possible interobserver errors

Paper Iris Disk Technique When the wax pattern is determined to

be appropriate, it is flasked and processed in scleral resin. The scleral blank is then finished, and it is polished using pumice and acrylic resin polish

The scleral blank is tried in and the middle of the pupil is marked while the patient gazes directly at the clinician.

The size of the iris is measured using a millimeter measurement gauge or optical scale.

The outline of the iris is then marked on the scleral blank using Carmen red ink.

This ink will transfer to the investing stone, facilitating the appropriate placement of the corneal prominence.

The blank is tried in again to verify the location and size of the iris.

The location of the iris will transfer to the investment and a scraper can then be used to create the corneal prominence of the prosthesis in the investment

A disk of ordinary artist's watercolor paper is punched out using a die.

The size selected should be 1 mm smaller than the measured size of the iris.

This will allow the iris to appear to be the appropriate size because the corneal prominence will cause a slight magnification of the iris disk patient's iris.

A good selection of colors for this purpose includes ultra-marine blue, yellow ochre, burnt sienna, burnt umber, yellow oxide, titanium white.

Colors should be mixed and reapplied in a layering fashion to mimic the colored striations in the patient’s iris.

Medial canthus

Pupil

IRIS ANATOMY

Begin by painting the darkest color, the area toward the outer edge of the iris ring (limbus).

The color of the limbus varies from eye to eye, but it usually is a combination of gray and iris body color.

In the natural eye, it can appear as a shadow from the overlapping sclera, covering the edge of the cornea.

Next the collarette is painted. It is usually a lighter color than the body of

the iris. A black spot should be painted in the

center of the disk to represent the pupil

The diameter should mimic the natural pupil under indoor light conditions.

This will make size appear relatively appropriate under most conditions.

After the paint has dried, a drop of water is applied to create the magnification of the corneal prominence and the color matched.

Using a flat-end bur, a flat surface is prepared in the scleral blank for the iris painting.

A sprue wax is luted to the prepared flat surface and tried in.

The orientation of the surface is adjusted until the sprue points directly at the observer while the patient looks directly into the observer's eye.

This will ensure that the prosthesis and the natural eye will have the same gaze

•Using a large abrasive stone, the entire anterior surface of the scleral blank is reduced at least 1 mm.

•The remainder of the prosthesis is then painted to match the sclera of the natural eye.

Fine red embroidery threads are placed on the scleral painting to mimic the blood vessels of the patient's natural eye.

The entire scleral portion is then coated with monomer polymer syrup to keep the blood-vessel fibers in place and allowed to set.

Once the monomer-polymer syrup has set, the

scleral blank is replaced into the flask, and the iris painting is placed on the flat section.

Clear ocular acrylic resin is mixed and placed into the mold space and the flask trial packed.

Once trial packed, the flash is removed and the location of the painting verified to ensure that it has not moved during trial packing.

BLACK IRIS DISK TECHNIQUE

The natural eye is observed closely and the diameter of the iris is estimated using a millimeter measurement gauge or optical scale.

Ocular discs, which are used in the iris painting, are available in half- mm sized increments, ranging from 11 mm to 13 mm.

120

They come in black or clear, and either with or without pupil apertures.

Clear corneal buttons are available in the same sizes as the discs.

The buttons can also be purchased with pupils of various sizes already in place.

The technique employed in painting the disk produces a three-dimensional effect. oil pigments are employed in this technique but are mixed with a monomer-polymer syrup during the painting process.

This mixing procedure provides some degree of translucency in the iris painting and permits rapid drying of the pigments

The basic eye color or background color is observed along with the limbus color.

The background color is applied to the disk first, using brush strokes from the center toward the periphery.

After the background color is applied and dried, a coat of the clear syrup is applied and allowed to dry.

Characteristic striations are applied over the clear layer and allowed to dry. A second clear layer is then applied and further characterization accomplished

After the second layer is dried, the limbus color is matched around the periphery of the disk and a third clear layer applied.

The color around the pupil is applied over the last clear layer and the final color evaluated with the water interface.

After a satisfactory color match has been obtained, a final clear layer is applied and allowed to stand for 15 minutes.

A single droplet of the monomer-polymer syrup is then placed in the center of the iris disk and the lens button is gently placed and centered.

The positioning of the iris-lens assembly on the wax scleral pattern is the most important phase in fabrication of the prosthesis.

Fix the lens button to the scleral pattern in a manner such that the apparent gaze of both natural and artificial eyes is on the same object, or parallel to one another and in the same plane.

The size of the lens assembly selected should be large enough to include the limbus.

The lens assembly is placed in a slight depression in the scleral pattern, and a thin layer of wax should be brought up over the curvature of the lens assembly.

This thin layer of wax will allow the opaque white scleral acrylic resin to flow up over the edge curvature of the lens assembly during the packing procedure, forming a very thin, translucent layer.

The finished pattern is then invested in a small two-piece brass flask.

The resulting scleral blank is deflasked, trimmed, and polished

The position and gaze of the artificial eye is again observed.

The sclera is slightly roughened using sandpaper disks in preparation for adding the simulated vasculature.

Rayon-thread fibrils are placed onto the surface of the sclera using the monomer- polymer syrup.

The pattern and type of vessels ( tortuous, straight, branched) of the opposite eye are reproduced.

The colors found in the sclera are usually yellow and blue, or combinations of these. Greens and browns can also be present.

The scleral painting begins with the application of a wash of yellow comparable to that found on the patient's natural eye.

Next, blue is added, which is usually located inferior and superior to the iris.

Finally, any characteristic details present in the natural eye are added.

Once complete, a coat of monomer and polymer is applied to the sclera.

The eye is now ready for the final processing, the application of a layer of clear acrylic resin

The prosthesis is cleaned and placed in socket. The fit of the artificial eye are evaluated and adjustments are made as necessary.

Digital imaging in the fabrication of ocular prosthesesIoli-Ioanna Artopoulou, DDS, MS,a Patricia C. Montgomery,b Peggy J. Wesley, CDA,c (J Prosthet Dent 2006;95:327-30.) Using digital imaging in the fabrication of the

ocular prostheses presents several advantages compared to the conventional oil paint and monopoly iris painting technique

The digital image provides acceptable esthetic results be cause it closely replicates the patient’s iris with minimal color adjustments and modifications.

The described technique is simple, decreases treatment time, and requires minimal artistic skills, which are necessary in the iris painting technique .

However, special digital photography equipment and settings, as well as computer software that allows for image adjustments, are required.

Make an impression of the anophthalmic socket with a stock acrylic resin tray designed for ophthalmic impressions (Factor II Inc) using the ophthalmic irreversible hydrocolloid (J-603 Special Formula Alginate; Factor II Inc).

Pour a master cast and fabricate a wax pattern using baseplate wax (Truwax Baseplate Wax; Dentsply Intl, York, Pa).

Evaluate the wax pattern in the patient, and evaluate and finalize the sculpting following the eye socket contours and lids configuration

Make a digital photograph of the patient’s iris using a digital camera (Canon EOS Digital Rebel; Canon Inc, Tokyo, Japan) with a macro lens (Canon Macro Lens EF 100 mm f/2.8 USM; Canon Inc) and a ring flash (Canon Macro Ring Lite Flash MR-14EX; Canon Inc) attached.

Set the shutter speed to 125 seconds, the aperture to F 16, and the sensitivity to ISO 640

Evaluate the photograph and compare it to the patient’s iris.

Using graphics software (Photoshop 7.0; Adobe Systems Inc, San Jose, Calif),

adjust for slight differences in color, brightness, contrast, or hue, and format the image.

Print the final image on 20-lb white paper with brightness87 (HP Office; Hewlett-Packard, Palo Alto, Calif) using a laser printer with a color-ink print cartridge

Cover the paper iris with 3 light coats of water-resistant spray (Workable Fixatif; Krylon, Solon, Ohio) used for artwork, and attach it to the ocular disk.

Use monopoly syrup (J-305 Monopoly Syrup;Factor II Inc) to position the ocular button (Factor II Inc) on the iris, and paint around the edges of the button and the disk to achieve maximum seal

Ocular button positioned on paper iris using monopoly syrup

Disk assembly attached to wax pattern and ready for trial insertion

Attach the disk assembly to the wax pattern and evaluate it in the patient.

Process the selected scleral acrylic resin at the same temperatures, using the procedure previously described for the conventional technique

After characterization is added, reprocess the ocular prosthesis with clear acrylic (Factor II Inc) using the previously described temperatures.

Pumice and polish the completed eye and insert it

COMPLICATIONS IN FITTNG ANOPHTHALMIC SOCKET

Ptosis: Superior eyelid ptosis is a frequent problem in

the restoration of an anophthalmic patient.

Pseudoptosis is due to the loss of volume between

the implant and the lids after removal of the eye.

If the physiological function of the eyelids is intact, correction of Pseudoptosis is achieved by increasing the volume of the prosthesis in the socket.

This condition usually occurs whenever a small, poorly fitted prostheses is used.

A simple technique of correcting Pseudoptosis is to make a larger prosthesis that will thrust forward and separate the eyelids

Persistent ptosis requires modification of the ocular prosthesis to correct for a deficient levator muscle, which causes the upper eyelid to droop..

Attempts aimed at increasing the size of the ocular prosthesis, as seen in Pseudoptosis, will not correct the problem in persistent ptosis.

The tension on the superior lid forces the larger prosthesis downward, thus depressing the lower eyelid, deflecting the gaze downward and creating patient discomfort

A thin transparent shelf can be made across the

front surface of the eye to hold the upper eyelid at the desired open position. The shelf is 3 to 4 mm wide and is placed along the upper limbus.

This modification of the prosthesis works well for ptosis caused by a superiorly migrated, large, spherical implant with limited socket space between the implant and the upper eyelid.

The major drawback to the shelf is that eye cannot blink or close. The weight of the upper eyelid and the action of the orbicularis muscle may press the eye downward.

This may be corrected by adding material to the inferior tissue surface of the prosthesis to contour it backward and upward. The surface above the shelf can be reduced to decrease the weight of the prosthesis and to create space for a tight upper eyelid.

Ectropion: - Inferior displacement of the implant can lead to

the loss of the inferior fornix and cause ectropion of the lower lid. Patients have difficulty with retention of the prosthesis, since it has a tendency to slip down and out over the everted lower lid.

This is rectified by extending a thin lower edge that will press downward upon the tarsus, and rotate it into a more vertical plane, thus creating a lower fornix.

The lower edge should be rounded and at least 1 mm in thickness so it will not cut into the socket.

The lower fornix will deepen within minutes of modification, and insertion of the prosthesis and retention will improve

Sagging lower eyelid: The weight of the prosthesis, and the contraction force of the upper eyelid on the prosthesis can cause a downward displacement of the lower eyelid, causing it to droop.

Degenerative disease may also weaken the lower eyelid, causing it to droop. By removing resin from the mid inferior margin of the prosthesis, downward pressure against the middle of the lower fornix is relieved.

Wax is added to extend the nasal and temporal aspects of the inferior margin to create pressure in the medial and lateral areas of the lid.

This directs the weight of the prosthesis where the lower eyelid is strongest, near the palpebral ligaments. These modifications tilt the tarsus of the lower eyelid favorably so that the eyelid margin is elevated.

Ocular implants are classified as

1. Integrated 2. Semi - integrated 3. Non-integrated and 1. Buried or 2. Non-buried

Integrated implants are designed to improve prosthesis motility by coupling to the overlying prosthesis. Implants is exposed through the conjunctiva to be directly coupled to the prosthesis with a peg, pin, screw or other method.

Semi-integrated ocular implants consist of an acrylic resin implant with 4 protruding mounds on the anterior surface. These acrylic resin mounds on the implant protrude against the encapsulating tissue. When an ocular prosthesis is made, a counter contour to the implant is formed on the posterior surface of the prosthesis.

Nonintegrated implant This is done by placing a hollow or solid acrylic resin sphere ranging from 10 to 22mm in diameter.

The placement of an orbital implant into an

enucleated socket was first described by

Frost in 1886

Soil described an improved surgical method of placing the orbital implant deep within the muscle cone, and buried beneath the posterior layer of Tenon’s capsule, following the enucleation of the eye .

The optic nerve and its associated vessels are severed and tied close to the posterior wall of the capsule. The implant is placed and the posterior portion of Tenon’s capsule is closed over the implant providing the first layer of closure.

Next, the anterior portion of Tenon’s capsule and conjunctiva are then closed to form the second and third layers over the implant. The horizontal rectus muscles are then attached to the medial and lateral fornix.

It is the movement of the fomix in the enucleated socket that provides the motility to the artificial eye. For example, as a person looks up. the inferior fomix shortens, the superior fornix deepens and the prosthesis revolves upward

By utilizing the posterior layer of Tenon’s capsule,a larger implant can be placed deep within the muscle cone decreasing the incidence of implant migration and reducing the tension on the anterior Tenon’s capsule sutures.

The larger implant reduces the volume deficit in the superior and inferior sulcus. preventing enophthalmos which can be produced by smaller implants.

Postoperative complications may develop during the first weeks following surgery.

Early extrusion of the implant may occur secondary to orbital hematoma formation and infection, traumatic manipulation of the tissues, or placement of too large an implant. thus creating excess tension on Tenon’s capsule

The technique of wrapping the orbital implant with fresh or preserved scleral tissue is thought to be a deterrent for extrusion and migration of the implant and it is a technique used quite frequently with enucleation

After enucleation. a plastic conformer and corticosieroid antibiotic ointment is placed in the socket.

The conformer should fit the contour of the socket and fill the depths of the fomices.

The conformer should not be removed by the patient, and should be unnecessary, as it is designed with drainage holes to allow mucoid discharge to escape and for insertion of postoperative medication.

The plastic conformer is left in place for 4 to 6 weeks to reduce edema and maintain the socket contours for the prosthetic eye.

Following healing of the anophthalmic socket, a stock or custom eye should be placed temporarily for cosmetic and psychological reasons.

CRITERIA FOR SUCCESS OF CRANIOFACIAL OSSEOINTEGRATED IMPLANTS

According to “Swedish council on Technology assessment in Health care”. The criteria for success is as follows.

Implants are immobile as verified by clinical examination.

No prolonged symptoms, such as pain, infection, tactile disorders or nerve damage should be present in connection with the implants.

Penetrated soft tissue should be free from irritation in at least 85% of regular out patient postoperative checks.

At least 95% of the temporal bone implants and at least 75% of other extraoral implants should be functional after 5 years.

The orbital defect

The ideal defect is circumscribed fully by bony orbital rim. The eyebrow should be intact. The soft tissue defining the defect should be thin and immobile. The surface with in the defect may be lined with a skin graft or even a free tissue flap.

An orbital defect may be the result of a congential anomaly (facial cleft), trauma (gunshot wound, road traffic accident) or surgery. Even with the advent of microscovascular surgery and free tissue transfers, surgical reconstruction alone cannot fully restore this area. Prosthetic rehabilitation is needed.

If the defect is more extensive, bone and softissue grafting should be considered to restore missing portions of the orbital rim, zygoma, or temporal or midface regions before implant placement. The surgical restoration of contour can contribute to a less extensive prosthesis.

Implant Placement

Implants are commonly placed in the orbital rim most often superiorly and laterally.

Placement in the inferior rim is desirable if the shape of the defect and access permit.

This improves the stability and retention of prosthesis.

In larger defects extending beyond the orbital rim, implants can be placed in the zygoma or maxilla.

Evan a single implant can help stabilize and retain a prosthesis.

Surgical Positioner

Actual placement of the implants is guided by a surgical positioner.

This is an acrylic resin prototype of the prosthesis that is used intraoperatively.

It indicates the ideal position for implant placement.

It also serves as guide for selection of the retentive mechanism and later as a time saving reference for the shape of the prosthesis.

The surgical positioner also helps determine if preprosthetic surgery is needed before implant placement. Most often, the lateral superior aspect of the orbital rim needs reduction to place an implant at the location and remain with in guidelines of the positioner .

Implant angulation should be parallel to the frontal plane of the face or be inward slightly.

A protrusive angulation can interfere with positioner contour and require compromise of the ideal shape of the prosthesis.

At the same time implant should not be over-angulated inward because prosthetic access for fabrication of retentive mechanism can be hampered.

This is true especially in smaller shallow defects when a soft-tissue flap has been used to close the opening of the defect.

Abutment selection and retention systems

The shortest abutment that protrudes to 1 to 2 mm above the level of skin should be selected at second-stage surgery.

This can minimize stress to the implant and still allow for hygiene and prosthetic access.

A shorter abutment takes up less space in conjunction with the retentive mechanisms.

At second-stage surgery, the gauze strip surgical dressing should be wrapped carefully around the abutments and under the healing caps so that close adaptation of skin to the abutment and underlying bone is achieved.

Rubenstein reported that orbital prostheses were fabricated with a wider variety of attachments than any other type of bone-anchored facial prosthesis :

bar clips, magnets, ball studs or a combination of

types.

Bar-clip systems yield the highest retentive forces.

good retention for large defects, especially when there are implants in only the superior orbital rim.

When implants are splinted together by the bar, loading can be shared among them.

This type of system permits retention and support beyond the actual position of implant.

At least two implants must be used for this system, but three or more spread in a slight arch are preferred to control and distribute forces

Because the mechanism takes up more space than individual magnets, care must be taken that the bar does not interfere with the ideal position of the ocular prosthesis.

REQUIREMENTS of the bar system so as not to stress the implants.

Impression making and bar construction can be difficult, especially if the implants are excessively divergent (more than 350) or widely distributed around the orbital defect. Asymmetric withdrawl of the prosthesis can result in amplification of loads to the implants.

Some divergence of implants is desirable to offer stability of the prosthesis against horizontal forces

Use is limited: when the implants are divergent, and they

can introduce forces that are not along the axis of the implants.

Like the bar-clip system, a prosthesis with ball attachments can be more difficult for the patient to place than one with magnetic attachment.

No retention system is ideal for all situations; each case must be evaluated to select the optimal one

PROSTHETIC TECHNIQUES:

I) Fabrication of the ocular prosthesis:Ocular prosthesis is made in conjunction with the surgical positioner because its shape and position relate to the overall shape of the orbital prosthesis.

A stock eye piece can be used. However, custom fabrication yields the best aesthetic results.

A pyramidal index of acrylic resin is incorporated on to the back surface of the eyepiece to aid in registering its position in the wax prototype and for subsequent mold making.

II) Impression making: Impression making for an orbital prosthesis

varies depending on the anatomic configuration of the orbital defect, location of implants and type of retention system selected

If individual magnets are used for retention, the MAGNACAPs are threaded into the abutments, and the transfer magnets are placed on them. These can be connected with autopolymerising resin to stablize them in impression.

The impression can be made using irreversible hydrocolloid, a silicone rubber . The impression should include the entire midface to provide adequate references and landmarks for accurate sculpting

Orientation lines are marked on the patient indelible pencil and will be transferred to the cast to aid this process. After removal of the impression and disinfection, LAB-ANALOGUE CAPS are placed against the transfer magnets and the impression is poured in dental stone.

III Design and Fabrication of resin plateThe resin plate retains the retentive components in a rigid base and provides stability for the prosthesis. In most cases, it should be as small as possible so as not to interfere with the placement of the ocular prosthesis

Magnets are placed on the lab-analogue caps on the cast.

Wax is used to block out the defect and the abutments

The resin engages this area to help retain the magnets in the plate. The area is bordered with boxing wax, and clear autopolymerising acrylic resin is poured over the area, covering the magnets and engaging the retentive rim. The thickness should be minimal and uniform to control distortion

A sprinkle on method can be used to apply the resin to better control the thickness of the plate. Alternatively, colourless urethane dimethacrylate visible light cure resin can be used to fabricate the plate. It is cured initially on the cast with a handheld light and then placed in the curing unit to complete curing.

The processed plate is shaped not to interfere with the ideal contour of the prosthesis. It is adjusted on cast and then tried on the patient. Complete engagement of retentive elements should be verified

IV Sculpting the wax prototype:This is where art takes over from science. To achieve a life like orbital prosthesis, attention to anatomy and surface detail is important. Input from the patient and family members is encouraged during this process.

To begin the sculpting process, the ocular prosthesis is attached to resin plate with soft utility wax while both are on the mastercast, using the orientation lines as a guide. When the prosthesis is transferred to the patient, depth, position, and gaze are evaluated relative to natural eye.

V Mold making: A three – piece mold of white improved dental

stone is made : tissue side, eyepiece and outer surface.

Once the wax prototype is completed, its outline is marked on the cast with indelible pencil .

An impression of the defect extending beyond the margins of the prosthesis is made with duplicating silicone elastomer and resin forced with plaster backing.

The periphery of this impression is poured in stone so that the center of the defect is left open. Registration keys are placed in the tissue side of the mold.

Lab-analogues of magnetic caps are placed on the magnets with in the resin plate.

The wax prototype is seated back on the cast by using the transferred pencil line as guide for orientation, and the margins are sealed.

Skin surface detail can be refined at this time

Stone is poured into the back of the wax

prototype through the opening of the cast .

Once set, wax spacers to facilitate later mold seperation are placed in the first piece of the mold, a seperator is applied to the stone surface, paper tape or wax is used to box the mold, and the top portion or outer surface of the mold is poured .

Once the stone has set, the mold is separated and the eyepiece and resin plate are removed. The mold is cleaned with boiling water and detergent to remove all wax residue

Before casting the prosthesis, silicone elastomer is used to make a mold of the outer surface of the resin plate while it is in place of on the tissue side of the mold.

The impression material should be applied with a syringe around the edges to capture the ledge on the tissue side of the plate.

Then a two piece silicone mold is of the eyepiece and this is poured in stone. This stone reproduction is used in the mold in place of resin eyepiece during processing to protect it from damage. These steps allow the resin plate and prosthesis to be remade without the patient and the prosthesis present, when a replacement prosthesis is necessary.

Maintenance of Prosthesis To maintain the health of the implants

and surrounding soft tissue and to preserve the prosthesis and retention mechanism.

Bone anchored facial prosthesis does require more care on the patient’s part and closer professional follow-up than one retained with adhesive.

HOME CARE AFTER ABUTMENT CONNECTION Follow up management actually begins once

the abutments have been placed. After the initial healing period and once a surgical dressing is no longer needed, the patient should be instructed to clean this area on a daily basis

The purpose is to remove cellular material on the skin or abutment, which can come from the interface of the epithelium and abutment.

This is performed with a soft, end tuft nylon bristle toothbrush, an interproximal dental brush or a cotton swab. To facilitate cleaning the area should be moistened first with an even mixture of hydrogen peroxide and water to soften any dried debris

When checking abutment tightness, an abutment clamp should be placed on the abutment body to provide countertorque so that undue force is not placed on the implant.If the abutment loosens, complete seating should be verified before retightening. This is done with an abutment holder.

HOME CARE AFTER PROSTHESIS PLACEMENT On the day that the prosthesis is given to the

patient, adequate time should be allotted for instructions on placing and removing the prosthesis as well as proper maintenance of the prosthesis, abutments, and surrounding skin areas. This information should be written and given to the patient, and all steps should be demonstrated.

patient should be careful when removing the prosthesis so that the thin margins do not tear and the silicone rubber does not separate from the resin plate

At night, the prosthesis should be removed and cleaned. The patients should wash their hands first to decrease chances of soiling the prosthesis during handling. All surfaces of the prosthesis should be cleaned gently with a soft, nylon-bristle toothbrush and mild soap and water

The prosthesis should be patted dry with a towel and placed in a covered container.

A denture cup or similar type of covered container can be used.

Should be stored away from extreme heat or direct sunlight, which can cause degradation and discolouration of the prosthetic material.

The prosthesis should not be worn during sleep so that air can circulate around the abutments to help maintain skin health

conclusion

The goal of any prosthetic treatment is to return

the patient to society with a normal appearance and

reasonable motility of the prosthetic eye. The

disfigurement resulting from loss of eye can cause

significant psychological, as well as social

consequences. However with the advancement in

ophthalmic surgery and ocular prosthesis, patient

can be rehabilitated very effectively.

The maxillofacial Prosthodontist should provide prosthetic treatment to the best of his ability and should also consider psychological aspects and if necessary the help of other specialist should be taken into consideration.

Sophistication in the surgical and prosthetic reconstruction of structural and functional defects in the craniomaxillofacial region improves the final rehabilitation results, if carefully planned, unbiased rehabilitation regimens are established

Bone anchored implant retention offers patients who wear facial prosthesis increased security, especially with large defects or where the prosthesis rests on highly mobile tissues. Perspiration and vigorous physical activity will not affect the retention of bone-anchored prosthesis.

Independence from reliance on adhesives for retention frees the patient from tedious task of applying and removing adhesive at each application and removal of prosthesis. It prolongs the life of prosthesis, because the edges are not subjected to excessive handling.

The implant team must develop a co-ordinated treatment plan that is delivered in an efficient manner. As much attention should be paid to the fitting and care of soft tissues as to issues of hardware articulation and registration.

A commitment of follow-up for the clinical evaluation of implant tissues and the maintenance and periodic replacement of the facial prosthesis are a team responsibility and in the best interests of the patient.

Textbook of Medical Physiology – GUYTON AND HALL Review of Medical Physiology - WILLAM F. GANONG Medical Physiology – CHAUDHARY

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