1. ORBITAL IMPLANTS DR. RESHMA PETER
2. Anophthalmia-Absence of globe Defined as an orbit not containing an eye ball, but has orbital soft tissues usually acquired, rarely congenital The most common cause - enucleation of the globe
3. SURGICAL PROCEDURES IN THE REMOVAL OF AN EYE Classified into three categories Evisceration- Removal of the contents of the globe leaves the sclera ,fat,EOM, and other adjacent structures of the eye intact and sometimes the cornea in place. Enucleation- Removal of the eye leaves EOM and remaining orbital contents intact. Exenteration Removal of the entire contents of the orbit including EOM
4. Tenon's capsule- Thin membrane which envelops the eyeball from the optic nerve to the limbus Separates eyeball from the orbital fat Forms a socket in which it moves In front it adheres to the conjunctiva. After enucleation orbital implant inserted to the Tenon's capsule in order to keep the orbital size to keep eye animation
5. Eye socket Eyelids Conjunctival fornices Orbital structures(bony cavity and soft tissues)
6. Common causes requiring socket reconstruction Congenital (anophthalmia ,microphthalmia) Trauma Tumour scarring
7. Acquired anophthalmos After enucleation/evisceration/exenteration
8. Ideal anophthalmic socket 1.A centrally placed, well-covered, buried implant of adequate volume, fabricated from a bio-inert material 2. A socket lined with healthy conjunctiva and fornices deep enough to retain a prosthesis and to permit horizontal and vertical movements of an artificial eye 3. Eyelids with normal position ,appearance and adequate tone to support a prosthesis 4. A supratarsal eyelid fold that is symmetric with that of the C/l eyelid
9. 5. Normal position of the eyelashes and eyelid margin 6. Good transmission of motility from the implant to the overlying prosthesis 7. A comfortable ocular prosthesis that looks similar to the sighted, contralateral globe and in the same horizontal plane
10. Enucleation/evisceration secondary implantation surgery Conformer is placed in the conjunctival fornices to maintain the conjunctival space conformer is replaced with a custom-made ocular prosthesis typically fashioned 4–6 weeks ORBITAL IMPLANT CONFORMER OCULAR PROSTHESIS
11. Orbital implant typically placed at the time of evisceration or enucleation Ocular prosthesis fitted subsequently
12. Anophthalmic surgery Successful anophthalmic surgery is achieved when the anophthalmic patient obtains a painless, non-inflamed eye socket with adequate volume restoration an artificial eye that looks and moves almost as naturally as a normal eye The optimal time to achieve the best functional and cosmetic result for the anophthalmic patient is at the time of enucleation
13. Most socket reconstructive surgeries are required to address the following problems: 1. A volume deficit following loss of the globe 2. Contracture of the socket 3. Orbital implant exposure, extrusion, and malposition
14. History 500 B.C.:Egyptians and Romans wore ocular prostheses 1555 :Johannes Lange (Lowenberg, Germany) 1st to mention enucleation (or extirpation as it was called then) 1583 :George Bartisch 1st recorded description of removal of an eye for treatment of severe ocular disease (Extirpation)
15. • 1579 :Ambroise Pare described the 1st prosthesis which was made of metal and coated with paint . • 1841: O’Ferrall (Dublin) and Bonnet (Paris) established current enucleation technique • 1817 :1st recorded evisceration by James Bear • 1874: Noyes -1st to perform a routine evisceration procedure •
16. 1884: P.H. Mules developed a unique technique for evisceration a milestone in ophthalmic surgery He inserted a hollow glass sphere (the “Mules” sphere) into the scleral cavity after removal of the cornea and intraocular contents Since then Sponge, rubber, paraffin, ivory, wool, cork, cartilage, fat, bone, Vitallium, platinum, aluminum, silver, and gold were used as implant.
17. 1886:Frost 1st described the placement of an orbital implant into an enucleated socket 1820s-1890s :Enamel prostheses introduced ;expensive and not durable. 1835 :Germans introduced cryolite glass made of arsenic oxide and cryolite from NaAlF grayish-white color suitable for a prosthetic eye a tube of glass was heated on one end until the form of a ball obtained. Various colors of glass used to imitate the natural eye color
18. • 19th century:German craftsmen ("ocularists") began to tour the US 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.
19. After the onset of WW II, when German glass blowers no longer toured US,the US and practitioners developed prostheses using oil pigments and plastics. •1940 :Naval dental school used acrylic resin in fabricating a custom ocular prosthesis. The acrylic eye was •easy to fit and adjust •Unbreakable • inert to ocular fluids •aesthetical good •longer lasting •easier to fabricate
20. • 1950s:A variety of implant designs were tried with an attempt to indirectly couple the implant to an overlying artificial eye by modifying the anterior surface of the implant as as the posterior surface of the prosthesis. • The Allen and subsequently the Iowa enucleation implants were buried integrated ( integrated”) implants.
21. 1950s and 1960s :Troutman, Uribe, Iliff - magnetic implants 1987 :Universal implant 1989:spherical implants made of silicone, glass, or polymethylmethacrylate (PMMA) mid- to late 1980s The introduction of coralline hydroxyapatite orbital implants in enucleation, evisceration, or secondary orbital implant surgery Several other porous implant materials have since been introduced as alternatives (e.g. synthetic hydroxyapatite, porous polyethylene, aluminum oxide).
22. Anophthalmic implant: Material or substance used to replace an enucleated or eviscerated globe (e.g. polymethylmethacrylate, silicone,hydroxyapatite, aluminum oxide, porous polyethylene, etc.) Porous implant: Refers to an implant with numerous interconnected pores or channels throughout its structure that permit fibrovascular ingrowth (e.g. hydroxyapatite, aluminum oxide, porous polyethylene) Nonporous implant: Refers to an implant that is solid and does not allow fibrovascular ingrowth (e.g. polymethylmethacrylate, silicone)
23. Buried implant: an implant that has been placed within the anophthalmic socket with an overlying closed, smooth, uninterrupted conjunctival surface completely covering the anophthalmic implant Exposed implant: an implant that does not have an overlying closed, smooth, uninterrupted surface completely covering it. An exposed implant is an unwanted complication postoperatively with any implant
24. Integrated implant: an implant that can be directly coupled to the overlying prosthetic eye with a peg system. As there is a small break in the overlying conjunctiva through which the peg protrudes, Sometimes known as a partially exposed integrated implant Non-integrated implant An implant that has been placed within the anophthalmic socket that has no connection with the overlying prosthetic eye. There is a closed, smooth, uninterrupted conjunctival surface completely covering the anophthalmic implant. Also known as a “buried non-integrated implant”
25. Peg: A motility coupling post, made of titanium, which permits direct coupling of the implant movement to an overlying prosthesis. Pegs may be inserted within sleeves that are drilled into the anterior aspect of the implant.
26. Quasi-integrated implant (buried integrated implant OR indirectly integrated implant) An implant that has been placed within the anophthalmic socket with a closed, uninterrupted conjunctival surface completely covering an anophthalmic implant that has an irregular anterior surface, allowing indirect coupling (“quasi-integration”) of implant to overlying, modified prosthesis (e.g., Allen, Iowa, Universal, MEDPOR Quad implants). Recently designed magnetic coupling systems may also be classified as quasi-integrated .
27. Integrated implants designed to improve prosthesis motility by coupling to the overlying prosthesis. Implant is exposed through the conjunctiva directly coupled to the prosthesis with a peg, pin, screw or other method.
28. Semi-integrated ocular implants • consist of an acrylic resin implant with 4 protruding mounds on the anterior surface • These acrylic resin mounds protrude against the encapsulating tissue • The ocular prosthesis is made with a counter contour to the implant on the posterior surface of the prosthesis.
29. Nonintegrated implant done by placing a hollow or solid acrylic resin sphere ranging from 10 to 22mm in diameter.
30. Ideal orbital implant Maintain Natural Lid Shape : ability to receive a motility/support peg, to support the weight of the artificial eye to prevent lower lid laxity and malposition over time . Light Weight Porosity: The implant must allow vascular orbital tissues to invade its structure to: a) lock it into place and prevent migration b) allow it to fight infections from within the implant via the vascular bed infiltrating the implant c) support "healing from within" of any defect in the conjunctival-Tenon's closure
31. True Integration The implant must be directly integrated (e.g., via a peg) with the artificial eye to allow direct transfer of all available movement from the rectus muscles to the artificial eye Natural Biocompatibility: the implant must be a natural material and readily accepted by the tissues of the orbit to prevent "synthetic implant syndrome" i.e., pseudocapsule formation around the implant. This pseudocapsule is the body's way of walling off a foreign material Non toxic non allergic
32. Current Classification of Implants porous or nonporous, and in either category, the implants are non-integrated, integrated, or quasi-integrated Porous implants (hydroxyapatite, porous polyethylene, aluminum oxide) Nonporous implants (silicone,polymethylmethacrylate) Quasi integrated (or indirectly integrated) implants may be porous or nonporous and, because of their irregular anterior surface, are partially coupled to the overlying prosthetic eye (e.g., Allen, Iowa, Universal, MEDPOR ® Quad implant).
33. Acrylic sphere Acrylic, or methylmethacrylate is the most basic implant best used in cases of trauma, such as a severe gunshot wound to the orbit Silicone sphere similar to an acrylic implant but slightly more pliable. Non porous inert spherical implants
34. Non porous inert spherical implants Advantages Provide comfort and low rates of extrusion. Cost-effective choice in patients. Disadvantages decreased motility and implant migration.
35. Porous Orbital Implants Hydroxyapatite Perry (1985) introduced coralline (sea coral)(HA) spheres complex calcium phosphate regular and complete system of interconnecting pores ( 500-µm pore size ) secure attachment of the extra ocular muscles The most suitable for peg–sleeve system.
36. Disadvantages of HA: Surface is abrasive conjonctival thinning Extrusion or exposure infection Pyogenic granuloma formation Costly Synthetic HA implants developed by FCI Chinese HA Brazilian HA Less expensive Poor porous structure
37. Synthetic porous polyethylene (MEDPOR) a porous type of plastic Less biocompatible than HA Well tolerated by orbital soft tissue The surface is nonabrasive so extrusion is rare. They may be used with or without a wrapping material extra ocular muscles can be sutured directly onto the implant
38. available in spherical, egg, conical, and mounded shapes (MEDPOR ® Quad implant) The anterior surface can also be manufactured with a smooth, nonporous surface to prevent abrasion of the overlying tissue (e.g., MEDPOR ® smooth surface tunnel implant – SST™.
39. Aluminum oxide (Al 2 O 3, Alumina, Bioceramic implant) porous, inert substance permit host fibrovascular ingrowth Human fibroblasts and osteoblasts proliferate more rapidly on aluminum oxide than HA suggesting it is a more biocompatible substance than HA lightweight has a uniform pore structure and excellent pore interconnectivity The microcrystalline structure is smoother than the rough surfaced Bio-Eye A protein coating that forms after insertion prevents the implant from being recognized as a foreign body This inert nature of these implants is a potentially critical advantage in minimizing socket inflammation. Less expensive
40. Variety of Shapes Mesh- Spherical eggshaped
41. Advantages of vicryl mesh wrap Facilitates entry into the orbit by decreasing drag on surrounding structures Allows suturing directly to implant Eliminates need for donor tissue No risk of disease transmission Eliminates second surgical site Absorbable Allows 360 degree entry of fibrovascular tissue (as opposed to entry through scleral windows)
42. Non integrated Semi integrated Fully integrated Expandable implants IMPLANTS
43. Pegging Is an option of any of the porous implants, most commonly done with hydroxyapatite. It improves motility by allowing the pegged surface to fit into a corresponding groove in the back of the prosthesis . can promote infection and lead to extrusion
44. Orbital Implant Selection in Adults BETWEEN 15 AND 65 YEARS OLD porous implant -quasi-integrated implant such as the Universal (PMMA – mounded) or MEDPOR ® Quad implant (mounded) A nonporous sphere (e.g., PMMA, silicone), wrapped, centered within the muscle cone, and attached to each of the rectus muscles and inferior oblique muscle, SEVENTH DECADE OR BEYOND A nonporous implant simply placed into the orbit, without a wrap and without connection to the rectus muscles
45. Orbital Implant Selection in Children LESS THAN 5 YEARS AGE wrapped nonporous sphere implant 16- or 18-mm diameter Exchange with porous and bigger size is possible autogenous dermis-fat grafts 5 TO 15 YEARS AGE nonporous implants, either a PMMA mounded implant (e.g. Universal) or a wrapped sphere (e.g. PMMA, silicone).
46. 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. may be the result of a congential anomaly (facial cleft), trauma (gunshot wound, road traffic accident) or surgery.
47. 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 missing portions of the orbital rim, zygoma, or temporal or midface regions before placement. The surgical restoration of contour can contribute to a less extensive prosthesis.
48. 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. Even a single implant can help stabilize and retain a prosthesis.
49. 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. It 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 .
50. 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.
51. 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.
52. TECHNIQUE OF IMPLANT INSERTION Soil described an improved surgical method of placing the orbital implant 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 deep within the muscle cone, and buried beneath the posterior layer of Tenon’s capsule The posterior portion of Tenon’s capsule is closed over the implant providing the first layer of closure.
53. 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 fornix 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
54. By utilizing the posterior layer of Tenon’s capsule,a larger implant can be placed deep within the muscle cone which decreases the incidence of implant migration reduces the tension on the anterior Tenon’s capsule sutures reduces the volume deficit in the superior and inferior sulcus preventing enophthalmos which can be produced by smaller implants Orbital Sphere Introducer
55. 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 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
56. 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 fornices. The conformer should not be removed by the patient, as it is designed with drainage holes to allow mucoid discharge to escape 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 by stretching the fornices for the prosthetic eye. SMALL MEDIUM LARGE 20mm 23mm 26mm
57. • Following healing of the anophthalmic socket, a stock or custom eye should be placed temporarily for cosmetic and psychological reasons. • Patient should be taught how to insert and remove the eye (devote separate time, quiet room and a mirror) • Patient should be encouraged to minimize handling the artificial eye. • Daily removal and cleaning is not necessary.
58. Notch is superonasally
59. Lubrication may improve comfort (no tap water! Ringers, Saline or Artificial Tears may work well instead, packed in the eyedrops bottles) There is only one eye now. Encourage using the protective plastic glasses One artificial eye should serve for 6-8 years. Easily gets damaged while dropped down Advise annual check up.
60. Evaluating the socket of anophthalmic patient: 1) Socket is fit or infmalmed? 2) Lower lid is healthy or lax? 3) Can the patient blink naturally? 4) Any lagophthalmos? 5) Are the fornices deep enough? 6) Giant papillae of upper tarsal conjunctiva?
61. Evaluating the prosthesis 1) Artificial eye is well centered? 2) Horizontal symmetry? 3) Equal prominence? 4) High gloss, wet shine? 5) Scratches, debris of the surface? 6) Moving naturally within 10-15 degrees?
62. Types of ocular prosthesis Spherical or oval Stock or custom made Porous or non porous Chemical make up Presence or absence of motility post.
63. impression of the socket is taken Once the impression material sets to a firm consistency, the shape is copied into a wax mold prepared iris–cornea piece is positioned on the front surface of the wax pattern. mold is placed into the socket and modifi ed (reshaped) for comfort and to improve cosmesis The wax shape is then translated (using additional molds) into fine quality acrylic (from methyl methacrylate resin), painted, cured, and polished. Modified impression technique
64. Prosthesis
65. CRITERIA FOR SUCCESS OF CRANIOFACIAL OSSEOINTEGRATED IMPLANTS (According to “Swedish council on Technology assessment in Health care”) 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.
66. 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
67. II) Impression making: Impression making for an orbital prosthesis varies depending on the anatomic the orbital defect, location of implants and type of retention system selected daily hygiene procedures should be performed by the patient to maintain the health of the soft stabilization of the soft tissue to ensure fit and marginal adaptation of the prosthesis. This allows time for adequate healing Impression is made 8 – 12 weeks after of the abutments.
68. 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
69. 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 the transfer magnets and the impression is poured in dental stone.
70. III Design and Fabrication of resin plate The 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
71. 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
72. IV Sculpting the wax prototype: 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 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.
73. One or more of the following are helpful in creating the wax prototype : the patient tissue conforme r computeri zed images Surgical positioner photograp hs measuring devices (boley and contour gauges, calipers)
74. 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
75. 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
76. 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.
77. 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 require more care on the patient’s part and closer professional follow-up than one retained with adhesive.
78. 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 to remove cellular material on the skin or abutment, which can come from the interface of the epithelium and abutment.
79. This is performed with a soft, end tuft nylon bristle toothbrush, an interproximal dental brush or a cotton swab. The area should be moistened first with an even mixture of H2O2 and H2O 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.
80. 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. 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
81. The prosthesis should be patted dry with a towel and placed in a covered container. 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
82. Complications
83. Exposure and Extrusion of Implant Implant exposure may occur with any type of implant or at any time may lead to implant extrusion or explantation
84. Porous orbital implants have a lower incidence of implant exposure than traditional nonporous implants Predisposing factors 1. closing the wound under tension 2. poor wound closure techniques 3. Infection 4. mechanical or inflammatory irritation from the speculated surface of the porous implant 5. Delayed ingrowth of fibrovascular tissue with subsequent tissue breakdown
85. Preventive measures for implant exposure proper placement of the implant within the orbit two-layered closure of anterior Tenon’s capsule and conjunctiva Treatment : If few weeks, No infection simple reclosure or with a patch graft (eg, Sclera, temporalis fascia) If infection is suspected vigorous treatment with topical and systemic antibiotics an extrusion and removal of the implant may be avoided.
86. beyond 4–6 months, If non porous The defect should not be closed secondary orbital implant surgery should be arranged If porous, exposure <3mm >3mm Treat conservatively Wait 8 weeks for spontaneous closure no Close with scleral patch graft surgical repair is indicated Using sclera patch graft or temporalis fascia patch graft
87. TREATMENT OF VOLUME DEFECIT
88. Dermis fat graft
89. TREATMENT OF LID LAXITY
90. Lax socket and inferior fornix shelving : results from shifting of tissues within the orbit With time there is involutional relaxation of the supporting tissues of the inferior eyelid the weight and pressure effect of the prosthesis laxity of the lid inability to retain the prosthesis Treatment Use prosthesis of optimal weight and size Lateral tarsal strip fornix formation sutures to increase the depth of inferior fornix
91. FORNIX DEEPENING SUTURES
92. Anophthalmic ptosis Inadequate implant size Migration of the orbital implant Poorly fit prosthesis Laxity of the fibrous connective tissue Orbit trauma from the original injury/surgery Senile dehiscence of the levator aponeurosis Frequent manipulation of the eyelids to insert and remove the artificial eye also stretches the upper eyelid tissues drooping eyelid.
93. Pseudoptosis Due to the loss of volume between the implant and the lids after removal of the eye. Occurs with a small, poorly fitted prostheses If the physiological function of the eyelids is intact, correction of pseudoptosis is achieved by increasing the volume of the prosthesis in the socket. A simple technique of correcting pseudoptosis is to make a larger prosthesis that will thrust forward and separate the eyelids
94. Treatment Small amounts of ptosis may be managed by modification of the prosthesis correction of socket volume deficiency should be considered prior to levator surgery Once the other factors contributing to ptosis in the anophthalmic socket have been addressed tightening of the levator aponeurosis can be done
95. Treatment of enophthalmos : placement of a secondary orbital implant if no implant was placed at the time of primary surgery Dermis fat graft (DFG) is an option in patients with associated surface contracture Orbital floor implants. Autologous bone grafts Non autologous medpor Treatment of superior sulcal deformity implantation of fascia lata / sclera / bone / fat/ alloplastic material in upper eyelid
96. Anophthalmic ectropion Frequently associated with significant lower eyelid laxity A large or heavy prosthesis or frequent prosthesis removal may contribute to a stretching of the medial and/or lateral canthal tendons Rotation of the orbital contents inferiorly and anteriorly contribute to a shallow inferior fornix, tilt of the prosthesis, and lower eyelid ectropion
97. Treatment If the prosthesis is >5 years old, a new one may be required If the prosthesis is large then a thinner or lighter prosthesis may help correct the malposition Tightening the lateral or medial canthal tendon may remedy the situation Correction of eyelid retraction by recession of IR/ grafting of mucus membrane tissue inferior fornix
98. Contracted socket extensive loss of conjunctiva surface area deep scar formation shrinkage of orbital fat conjunctiva fornices contracture. the shrinkage and shortening of orbital tissues decrease in depth of fornices and orbital volume leading to inability to retain prosthesis. Guibor has classified clinically contracted socket into 4 morphological types
99. Causes Etiology related ・Alkali burns ・Radiation therapy Surgery related Fibrosis from the initial injury Poor surgical techniques during previous surgeries -enucleation /evisceration with extensive dissection of orbital tissue Excessive sacrifice of the conjunctiva and tenons capsule Traumatic dissection within the socket leading to scar tissue Multiple socket operations
100. Site related Poor vascular supply Severe ischemic ocular disease in the past Cicatrizing conjunctival diseases Chronic inflammation and infection Implant and prosthesis related Implant migration Implant exposure Not wearing a conformer/prosthesis Ill fitting prosthesis
101. Grades of contracted sockets. The soft tissue sockets were divided into five grades for the sake of convenience in management of contracted sockets. Grade-0: Socket is lined with the healthy conjunctiva and has deep and well formed fornices.
102. Grade-I: Shallow lower fornix or shelving of lower fornix Here the lower fornix is converted into a downwards sloping shelf which pushes the lower lid down and out, preventing retention of a artificial eye. shallow lower fornix and deep upper fornix resulting in upward migration of the prosthesis
103. Grade-II: Socket is characterized by the loss of the upper and lower fornices
104. Grade- III: Socket is characterized by the loss of the upper, lower, medial and lateral fornices
105. Grade-IV: Socket is characterized by the loss of all the fornices, and reduction of palpebral aperture in horizontal and vertical dimensions
106. Grade-V: In some cases, there is recurrence of contracture of the socket after repeated trial of reconstruction
107. Aims of reconstruction To establish stable fornices by increasing the surface area by (hard palate ,oral mucosal,skin graft) and if necessary by increasing size by orbital implant. The ocular prostheses should be light and take its support from infraorbital rim not from the lids.
108. Surgical principle First : obtain adequate palpepral aperture size (canthoplasty may be needed in grade3,4,5) Second : create adequate fornixes (lower,upper,lateral) insicion central in grade 2 while it can be at inferior position in grade 1. Third : perfect lining of the created fornix (hard palate ,oral mucosal,skin graft ,amniotic membrane)
109. Fourth be sure that the fornix created supported by orbital bony rim to create a stable and deep lower fornix, the lower edge of the graft should be sutured to the inferior orbital bone rim using anchor sutures . Fifth: the conformer used during healing for about 6 weeks then ocular shell prosthesis used there after. Sixth : central temporary tarsorrhaphy may be used.
110. Bone anchored implant offers 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 Independence from reliance on adhesives frees the patient from tedious task of applying and removing adhesive at each application and removal of prosthesis. It prolongs the life of prosthesis, as the edges are not subjected to excessive handling Follow-up for the clinical evaluation of implant tissues and the maintenance and periodic replacement of the facial prosthesis are a must
111. REFERENCES Clinical Maxillofacial Prosthetics-Thomas d. Taylor Maxillo Facial Rehabilitation – Prosthodontic and surgical consideration -JOHN BEUMER Prosthetic rehabilitation-Keith.F.Thomas Ophthalmic and Plastic and Reconstructive Surgery
112. THANK YOU!!!
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