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The fundamental objective in restoring a congenital as well as acquired defect of eye with an ocular prosthesis is to enable the patient to cope better with the difficult process of rehabilitation after an enucleation or evisceration. A cosmetically acceptable prosthesis is that reproduces the color, form and orientation of iris and allows the patient to return to accustomed lifestyle. A sequence of steps for construction of custom-made ocular prostheses is outlined in this case report using the advantages of digital imaging technique.

Ocular prosthesis motility was measured and compared in 15 patients with a primary baseball implant after enucleation of an eye, in 11 patients with a secondary baseball implant, in 12 patients with an Allen implant, and in 11 patients without any intraorbital implant. In all patients a noticeable lag of movement of the prosthetic eye was measured: in the extreme directions of gaze the excursions of the prosthesis were far less in comparison with the contralateral normal eye. For normal eye movement round the primary position of gaze, however, the prosthesis motility in the primary baseball and Allen implant group appeared to be sufficient to give a lifelike appearance. The average motility of the prostheses in these two groups did not differ. The motility in the secondary baseball group and in the group without an implant was evidently worse. In the last group the prosthesis motility was most impaired. We conclude that the insertion of an implant, even when inserted some time after the enucleation (a secondary implant), improves the motility of the prosthesis markedly. We recommend the primary baseball implant as the correction of choice after enucleation.

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Following Total Laryngectomy, Tracheo-oesophageal speech prosthesis offers the most reliable form of voice rehabilitation. Of the various prostheses currently available. The Provox voice prosthesis developed by the Netherlands Cancer Institute has been the most popular due to its superior design and in-dwelling nature.

At the Apollo Cancer Hospital, Hyderabad, 17 patients underwent speech rehabilitation with the Provox voice prosthesis between February 1999 and July 2000. Speech rehabilitation was successful in all patients with the majority (82%) developing Good—Excellent speech. Two patients required replacement and one patient discontinued use of the prosthesis. There were no complications in any of the other patients.

The coral-derived hydroxyapatite sphere is a popular, new integrated orbital implant designed to provide improved motility of the ocular prosthesis following enucleation. Although the implant has rapidly become widely used by ophthalmologists, there is little information available regarding the complications of this technique in a large series of cases. We report our results on our initial 250 consecutive cases of hydroxyapatite implantation for eyes enucleated primarily for intraocular neoplasms, with specific emphasis on the complication an their management. The reasons for enucleation included uveal melanoma (157 cases), retinoblastoma (70 cases), blind painful eye (22 cases), and intraocular medulloepithelioma (1 case). Prior treatment to the eye was performed before enucleation in 47 cases and included repair of ruptured globe (17 cases), plaque radiotherapy (18 cases), external beam radiotherapy (6 cases), and others (6 cases). During a mean of 23 months follow-up (range, 6 to 42 months), there have been no recognizable cases of orbital hemorrhage related to the implant and no cases of implant extrusion or implant migration. There was one case of presumed orbital infection (culture-negative) that resolved with intravenous antibiotics, and the implant was retained within the orbit. Other problems included conjunctival thinning in eight cases managed by observation and prosthesis adjustment and conjunctival erosion in four cases managed by combinations of scleral patch graft, conjunctival flap, and prosthesis adjustment. The conjunctival erosion was caused by a poorly fitting prosthesis in three cases and wound dehiscence in one case. The complication rate in eyes receiving prior radiotherapy or surgery was not increased. The hydroxyapatite integrated orbital implant is a well-tolerated motility implant without the high rate of extrusion and infection seen with other motility implants.

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Rehabilitation of facial defects is a complex task, requiring an individualized design of the technique for each patient. The disfigurement associated with the loss of an eye may result in significant physical and emotional problems. Various treat-ment modalities are available, one of which is the use of implants. Although implant-supported orbital prosthesis has a su-perior outcome, it may not be advisable in all the patients due to economic factors. The present article describes a simplified technique for the fabrication of a silicone orbital prosthesis by constructing a custom ocular prosthesis to achieve ideal fit and aesthetics. Multidisciplinary management and team approach are essential in providing accurate and effective rehabilitation.

The coral derived hydroxyapatite sphere is a popular, integrated orbital implant designed to provide improved motility of the ocular prosthesis following enucleation. Although the implant has rapidly become widely used by ophthalmologists, little information is available regarding the problems of this technique in a large series of cases. Experience with 250 consecutive cases of hydroxyapatite orbital implant use was reviewed and the problems of the implants and their management investigated specifically. The reasons for enucleation included uveal melanoma (157 cases), retinoblastoma (70 cases), blind painful eye (22 cases), and intraocular medulloepithelioma (one case). Earlier treatment to the eye was performed before enucleation in 47 cases and included repair of ruptured globe (17 cases), plaque radiotherapy (18 cases), external beam radiotherapy (six cases), and others (six cases). During a mean of 23 months' follow up (range 6-40 months), there have been no recognisable cases of orbital haemorrhage related to the implant, and no cases of implant extrusion or implant migration. There was one case of presumed orbital infection (culture negative) that resolved with intravenous antibiotics and the implant was retained within the orbit. Other problems included conjunctival thinning in eight cases managed by observation and prosthesis adjustment, and conjunctival erosion in four cases managed by combinations of scleral patch graft, conjunctival flap, and prosthesis adjustment. The conjunctival erosion was caused by a poorly fitting prosthesis in three cases and wound dehiscence in one case. The problem rate in eyes receiving prior radiotherapy or surgery was not increased. The hydroxyapatite integrated orbital implant is a well tolerated motility implant without the high rate of extrusion and infection seen with other motility implants. The prosthesis fit may contribute to the tolerance of the implant.

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Mutilation of a portion of a face can cause a heavy impact on the self image and personality of an individual. Surgical removal of an eye is a severe handicap to a patient because the most important sensory organ of communication is lost. Depending on the severity of the defect Ocular/Orbital prosthesis are required in these patients for rehabilitation. This case report details the clinical management of a patient following enbloc removal of an eye. Fabrication of a sectional two piece orbital prosthesis has been detailed. The importance of meticulous treatment planning to tackle the challenges faced in fabricating an orbital prosthesis is explained with relevant literature.

The technician by virtue of his profession plays an important role in fabricating silicone tongue prosthesis for a total glossectomy patient. The technician, with his skills and specialized knowledge in handling material, plays a valuable role as a member of the oncology team. A patient with total glossectomy can be rehabilitated by silicone tongue prosthesis as an aid to improve his speech and swallowing. This paper describes the technical steps involved in fabricating a silicone tongue prosthesis for an edentulous total glossectomy patient.

As a preparatory step towards the development of a complete habilitation program for children with congenital limb anomalies associated with maternal ingestion of thalidomide, the medical records of all patients with congenital limb anomalies referred to the Rehabilitation Institute of Montreal in the past decade were studied, and an examination and a thorough reassessment were made of 41 patients (21 males and 20 females). The medical and prosthetic aspects were dealt with in Part I of this paper. Part II describes, in a joint report, the results of psychiatric, psychological and educational assessments.

There was no evidence of major emotional disorder in any of the patients, although conflicts were intensified by the presence of the physical anomaly. No relation was found between intelligence, emotional adjustment and disability. The patient's attitude towards his disability and prosthesis is definitely influenced by the degree of parental acceptance of the handicap and by the character of the emotional undertones in the total environment. In order to favour the occurrence of the healthiest modes of development in these children, the authors believe that the medical profession should be made fully aware of the physical and emotional problems which may arise after the birth of a deformed child. It is considered very important that the mother should receive psychotherapeutic support as soon as possible after the child is born.

Summary

Prosthetic rehabilitation in post-oncologic patients after bone reconstruction are not substantially different than those of patients affected by severe atrophia of upper or lower jaw after bone reconstruction.

Aim of this paper is to evaluate the possibilities of prosthetic rehabilitation on these patients and to present our method. Prosthesis-based oral rehabilitation of such tumor cases rapresents a challenge.

The report analyses two cases of patients who underwent ablative oral surgery. Both have received a fibula free vascularised flap. The first was rehabilitated with a removable prosthesis fixed on the residual teeth, while the second with an implant supported prosthesis.

In case of carcinoma resection of the oral mucosa, the removable prosthesis guarantees a simplification in dental care operations. On the other hand, irradiated mucosa is frequentely unable to tolerate the friction created by the acrylic base. However, the fixed prosthesis can limit the view during follow-up controls.

In our school, according to all exposed reasons, we consider the implant supported overdenture prosthesis to be the best choice for those patients.

An ocular defect may affect a patient psychologically. An ocular prosthesis is given to uplift the patient psychologically and improve the confidence. Ocular prosthesis can be custom made or a stock shell. To improve the comfort and matching of the prosthesis with that of the adjacent natural eye an custom made ocular prosthesis is preferred. Different techniques are available to fabricate a custom ocular prosthesis, here we have used paper iris disk technique.

Loss of voice is a major concern after total laryngectomy. Tracheo-esophageal prosthesis was described in 1980 by Blom and Singer as a method of postlaryngectomy voice rehabilitation. Since then it has seen many phases of developments. Now it has evolved into highly effective method with success rates more than 90% and better quality of voice than other modalities. It also gives good quality of life and voice related quality of life. Though it is associated with some complications, they are easy to manage. All these have made tracheo-esophageal prosthesis the ‘Gold Standard’ of post-laryngectomy voice rehabilitation.

Large oro-facial defects result from cancer treatment consequences in serious functional as well as cosmetic deformities. Acceptable cosmetic results usually can be obtained with a facial prosthesis. However, retention of a large facial prosthesis can be challenging because of its size and weight. This article describes prosthetic rehabilitation of a 57-year-old man having a right lateral mid-facial defect with intraoral-extraoral combination prosthesis. A modified technique to fabricate a hollow substructure in heat-polymerizing polymethyl-methacrylate to support silicone facial prosthesis was illustrated. The resultant facial prosthesis was structurally durable and light in weight facilitating the retention with magnets satisfactorily. This technique is advantageous as there is no need to fabricate the whole prosthesis again in case of damage of the silicone layer because the outer silicone layer can be removed and re-packed on the substructure if the gypsum-mold is preserved.

Rationale: Enucleation implants are covered with a material that allows the fixation of the extraocular rectus muscles. Usually, the implants are covered in donor sclera, which implies the risk of infection transmission, inflammation and implant rejection, being also an expensive procedure. The new materials used for implant meshing should be tested and a safer and cost effective solution should be researched.

Objective: This study presents the results obtained after a 15-year use of an original prosthesis for the reconstruction of the orbital cavity after enucleation surgery.

Methods and results: 42 eyes of 42 patients who underwent enucleation surgery for choroidal malignant melanoma were included in the study. The surgical technique was very similar to the classic enucleation, the major difference being the implant of a prosthesis made out of a Polymethyl methacrylate (PMMA) ball covered by a Polyethylene terephthalate (dacron) shell used in cardiovascular surgery. All the patients had a very good technical result, without the inflammation of the orbital cavity, conjunctiva or eyelids, which demonstrates a very high material tolerability and an excellent cosmetic result. Late implant expulsion appeared in 7.14% of the patients (3 cases).

Discussion: The particularly good results obtained by using this technique, the absence of an inflammatory reaction after surgery, and the long lasting stability of the implant, recommend the method as being safe, with no major complications and a good esthetic result.

AbbreviationsPolymethyl methacrylate (PMMA), Malignant choroidal melanoma (CMM)

An implantable prosthesis that stimulates vestibular nerve branches to restore sensation of head rotation and vision-stabilizing reflexes could benefit individuals disabled by bilateral loss of vestibular (inner ear balance) function. We developed a prosthesis that partly restores normal function in animals by delivering pulse frequency modulated (PFM) biphasic current pulses via electrodes implanted in semicircular canals. Because the optimal stimulus encoding strategy is not yet known, we investigated effects of varying biphasic current pulse frequency, amplitude, duration and interphase gap on vestibulo-ocular reflex (VOR) eye movements in chinchillas. Increasing pulse frequency increased response amplitude while maintaining a relatively constant axis of rotation. Increasing pulse amplitude (range 0–325 μA) also increased response amplitude but spuriously shifted eye movement axis, probably due to current spread beyond the target nerve. Shorter pulse durations (range 28–340 μs) required less charge to elicit a given response amplitude and caused less axis shift than longer durations. Varying interphase gap (range 25–175 μs) had no significant effect. While specific values reported herein depend on microanatomy and electrode location in each case, we conclude that PFM with short duration biphasic pulses should form the foundation for further optimization of stimulus encoding strategies for vestibular prostheses intended to restore sensation of head rotation.

Bilateral loss of vestibular sensation causes difficulty maintaining stable vision, posture and gait. An implantable prosthesis that partly restores vestibular sensation could significantly improve quality of life for individuals disabled by this disorder. We have developed a head-mounted multichannel vestibular prosthesis (MVP) that restores sufficient semicircular canal function to recreate a 3D angular vestibulo-ocular reflex (aVOR). In this study, we evaluated effects of chronic MVP stimulation on locomotion in chinchillas. Two of three animals examined exhibited significant improvements in both locomotion and aVOR.

Bilateral loss of vestibular sensation causes difficulty maintaining stable vision, posture and gait. An implantable prosthesis that partly restores normal activity on branches of the vestibular nerve should improve quality of life for individuals disabled by this disorder. We have developed a head-mounted multichannel vestibular prosthesis that restores sufficient semicircular canal function to partially recreate a normal 3-dimensional angular vestibulo-ocular reflex in animals. Here we describe several parallel lines of investigation directed toward refinement of this approach toward eventual clinical application.

Extraoral implant retained prosthesis have been proven to be a predictable treatment option for maxillofacial rehabilitation. This case report describes the clinical and laboratory procedures for fabricating an auricular prosthesis.

In this case report, an auricular prosthesis was fabricated for a patient who lost the left and right external ear in an electrical burn. Extraoral implants and bar-and-clip retention for the proper connection of the auricular prosthesis to implant were used. This prosthesis was acceptable to the patient because of excellent support, retentive abilities and the patient’s appearance.

Loss of continuity of the mandible destroys the balance and symmetry of mandibular function, leading to altered mandibular movements and deviation of the residual fragment towards the resected side. Prosthodontic treatment along with physical therapy may be useful in reducing mandibular deviation and improving masticatory efficiency. Numerous prosthetic methods are employed to minimize deviation and improve masticatory efficiency which includes implant supported prosthesis, mandibular guide flange prosthesis, and palatal based guidance restoration. This article describes rehabilitation of hemimandibulectomy patient using twinned teeth (two rows of teeth) on the unresected side in the maxillary edentulous arch for whom implant supported prosthesis, mandibular guide flange prosthesis or palatal based guide flange prosthesis cannot be fabricated to improve the masticatory efficiency.

Facial defects resulting from neoplasm, congenital malformation or trauma can be restored with facial prosthesis using different materials and retention methods to achieve life-like look and function. A nasal prosthesis can re-establish esthetic form and anatomic contours for mid-facial defects, often more effectively than by surgical reconstruction as the nose is relatively immobile structure. For successful results, lot of factors such as harmony, texture, color matching and blending of tissue interface with the prosthesis are important. The aim of the presented case report is to describe the non-surgical rehabilitation, with polymethyl meth-acrylate resin, nasal prosthesis for a patient who received partial rhinectomy as a result of squamous cell carcinoma of the nose. The prosthesis was made to restore the esthetic appearance of the patient with a mechanical retained design using a spectacle glass frame without inserting craniofacial implants.

Maxillary obturator prosthesis is the most frequent treatment option for management of partial or total maxillectomy. Heavy weight of the obturators is often a dislocating factor. Hollowing the prosthesis to reduce its weight is the well established fact. The alternate technique to hollow-out the prosthesis has been described in this article which is a variation of previously described processing techniques. A pre-shaped wax-bolus was incorporated inside the flasks during packing of the heat-polymerized acrylic resin to automatically create the hollow space. The processing technique described is a single step flasking procedure to construct a closed-hollow-obturator prosthesis as a single unit. To best understand the technique, this article describes management of a patient who had undergone partial maxillectomy secondary to squamous cell carcinoma rehabilitated with a hollow-obturator prosthesis.

Revision stapedectomy with a malleus grip prosthesis is a technically challenging otologic procedure. The prosthesis is usually longer and extends deeper into the vestibule than a conventional stapes prosthesis, creating the potential to affect the vestibular sense organs. The prosthesis also bypasses the ossicular joints, which are thought to play a role in protecting the inner ear from large changes in static pressure within the middle ear. The prosthesis is in close proximity to the tympanic membrane, thus increasing the risk for its extrusion. We reviewed our experience with revision stapedectomy with the Schuknecht Teflon-wire malleus grip prosthesis in 36 ears with a mean follow-up of 23 months. The air-bone gap was closed to within 10 dB in 16 ears (44%) and to within 20 dB in 26 ears (72%). The incidence of postoperative sensorineural hearing loss was 8% (3 ears). There were no dead ears. Extrusion of the prosthesis occurred in 1 case (3%). Nearly 50% of patients reported various degrees of vertigo or disequilibrium during the first 3 weeks after surgery. These vestibular symptoms resolved by 6 weeks in all but 1 case. We did not find evidence of damage to the inner ear due to the length of the prosthesis or due to the potential for direct transmission of changes in static pressures within the middle ear to the labyrinth. Our results are similar to those published in the literature for malleus attachment stapedectomy and conventional revision incus stapedectomy.

Malignant tumours of the oral cavity that require resection of the tongue result in severe deficiencies in speech and deglutition. Speech misarticulation leads to loss of speech intelligibility, which can prevent or limit communication. Prosthodontic rehabilitation involves fabrication of a Palatal Augmentation Prosthesis (PAP) following partial glossectomy and a mandibular tongue prosthesis after total glossectomy [1]. Speech analysis of a total glossectmy patient rehabilitated with a tongue prosthesis was done with the help of Dr. Speech Software Version 4 (Tiger DRS, Inc., Seattle) twelve years after treatment. Speech therapy sessions along with a prosthesis helped him to correct the dental sounds by using the lower lip and upper dentures (labio-dentals). It was noticed that speech intelligibility, intonation pattern, speech articulation and overall loudness was noticeably improved.

Sjogren’s syndrome is a distinct clinical condition which includes xerostomia, ocular dryness, rheumatoid arthritis and other connective tissue disorders. Major oral problems reported by such patients include high caries rate, burning of oral mucosa, early tooth loss, increased tooth wear, poor tolerance for dentures and repeated failure of dental restorations. Prosthodontic therapy for this unique patient group is challenging and neglected due to the limited number of abutments, loss of vertical dimension and poor occlusion. Two year follow up of a patient of Sjogren’s syndrome, rehabilitated by a combination of fixed and removable prostheses with a simplified palatal salivary reservoir is presented. Though the patient felt an improvement in quality of life due to the prosthesis, slurred speech and frequent reservoir refilling remained problems.

Bilateral loss of vestibular sensation can disable individuals whose vestibular hair cells are injured by ototoxic medications, infection, Ménière’s disease or other insults to the labyrinth including surgical trauma during cochlear implantation. Without input to vestibulo-ocular and vestibulo-spinal reflexes that normally stabilize the eyes and body, affected patients suffer blurred vision during head movement, postural instability, and chronic disequilibrium. While individuals with some residual sensation often compensate for their loss through rehabilitation exercises, those who fail to do so are left with no adequate treatment options. An implantable neuroelectronic vestibular prosthesis that emulates the normal labyrinth by sensing head movement and modulating activity on appropriate branches of the vestibular nerve could significantly improve quality of life for these otherwise chronically dizzy patients.

This brief review describes the impact and current management of bilateral loss of vestibular sensation, animal studies supporting the feasibility of prosthetic vestibular stimulation, and a vestibular prosthesis designed to restore sensation of head rotation in all directions. Similar to a cochlear implant in concept and size, the Johns Hopkins Multichannel Vestibular Prosthesis (MVP) includes miniature gyroscopes to sense head rotation, a microcontroller to process inputs and control stimulus timing, and current sources switched between pairs of electrodes implanted within the vestibular labyrinth. In rodents and rhesus monkeys rendered bilaterally vestibular-deficient via treatment with gentamicin and/or plugging of semicircular canals, the MVP partially restores the vestibulo-ocular reflex for head rotations about any axis of rotation in 3-dimensional space. Our efforts now focus on addressing issues prerequisite to human implantation, including refinement of electrode designs and surgical technique to enhance stimulus selectivity and preserve cochlear function, optimization of stimulus protocols, and reduction of device size and power consumption.