|Year : 2012 | Volume
| Issue : 3 | Page : 193-197
The obturator prostheses for maxillectomy
A Meenakshi, Darshan Shah
Department of Prosthodontics, Tamil Nadu Government Dental College and Hospital, Chennai, India
|Date of Web Publication||19-Feb-2013|
Department of Prosthodontics, Tamil Nadu Government Dental College and Hospital, Opp. Fort station, Broadway, Chennai, PIN-No - 600 003, Tamil Nadu
Management of the patient with congenital or acquired defect of palate, resulting in communication between oral cavity and nose and/or maxillary sinus, presents challenge to the clinician. The prosthodontic management involves use of obturator prosthesis. This article discusses various aspects of the obturator prosthesis.
Keywords: Maxillectomy, maxillofacial prosthesis, obturator
|How to cite this article:|
Meenakshi A, Shah D. The obturator prostheses for maxillectomy. SRM J Res Dent Sci 2012;3:193-7
| Introduction|| |
"It is God-given right of every human being to appear human." Various maxillofacial defects cause facial disfigurement affecting quality of life of the patient. Among all intraoral defects, maxillary defects must be the most common one that can appear in the form of communication between oral cavity and maxillary sinus or nasopharynx. Depending on their origin, two groups for such defects can be congenital and acquired, which may result due to some injury or surgery. Such defects vary as far as etiology, location, and size are concerned. The size of the defect may vary from small to large, which may include parts of hard and soft palate, alveolar bone, floor of nasal cavity, and maxillary sinus and may extend up to floor of orbit and zygomatic complex.
In general, such defects can be prosthodontically rehabilitated by prosthesis called obturator. The obturator is a disc or plate, natural or artificial, which closes an opening or defect of the maxilla as a result of a cleft palate or partial or total removal of maxilla for tumor mass. The obturator can be of different types and designs depending on the defect to be restored.
This article reviews various aspects related to obturator prosthesis.
| Effect of Maxillary Defects|| |
The maxillary defects may lead to anatomical and functional deformity of the maxillofacial region. The defect will produce concern regarding facial deformity. As far as functions are concerned, it can produce difficulty in speech, mastication, and deglutition. Loss of partition between oral and nasal cavity will lead to passage of fluid into nasal cavity.
| Treatment Options for Maxillary Defects|| |
The defect involving maxilla can be rehabilitated either by surgical correction with plastic surgery or by obturator prosthesis. The treatment with plastic surgery will provide better results as far as esthetic and function are concerned. However in many cases, plastic surgery may be contraindicated because of advanced age of the patient, poor general health, very large defect, and poor blood supply because of radiation therapy. In such cases, a prosthetist may be called upon to treat the patient. The obturator prosthesis can rehabilitate the defect and can improve patient's quality of life. However by no means should maxillofacial prosthetic repair be considered a substitute for plastic repair, but in certain circumstances, it may be an alternative.
For rehabilitation of maxillectomy, patient objectives  should be the following:
- To restore the function: Speech, respiration, chewing, and deglutition.
- To restore the form: Facial appearance.
- The goals for the rehabilitation of maxillectomy patient.
- Separation between oral and nasal cavities to restore normal function of speech, respiration, and deglutition.
- To provide support to the soft tissue to restore the mid-facial contour and an acceptable aesthetic results.
- To provide support for the orbital contents to prevent ophthalmic complications such as enophthalmus and diplopia.
| Historical Background|| |
Correction of the maxillary defect can be done either by a surgical procedure or by prosthetic rehabilitation. The surgical treatment may be associated with donor site morbidity, demanding surgical procedures, and graft failure. The prosthodontic management is easier and technically less demanding, when compare to surgical correction.
The literature reveals the use of artificial material by Ambroise Pare in 1500s, to obturate the palatal defect. Pare used a dry sponge that was attached to the upper surface of the disc. When the sponge becomes moist by the secretion, it expands and holds the prosthesis in place. In another variation, he used a turnbuckle type of mechanism to hold the prosthesis in place. Pierre Fuchard (1728), the father of scientific dentistry, contributed significantly to maxillofacial prosthetics. He described two types of palatal obturators. One of the types has wings in the shape of propellers, which can be folded together while being inserted and spread out after insertion with a special key. In the other type, the retaining feature is in the form of a butterfly wings which are made to open by a key after the closed wings have been inserted through the palatal perforation.
William Morton (1869) used a gold plate to treat palatal defect. Later, in 1875, Claude Martin started using a surgical obturator for maxillary defects. In 1927, Fry described importance of impression making before surgery. Use of gutta-percha to hold a skin graft in position for surgical correction of maxillectomy was described by Steadman in 1927. 
- To obturate the defect temporarily during the period of surgical correction. 
- To act as a scaffold over which tissues can be shaped by surgeons.
- To restore patient's facial form, thereby improving aesthetics and self-image.
- In the case of large defects, where primary closure is not possible.
- When the patient's age and general condition contraindicate reconstruction surgery.
- In large size defect where results of reconstructive surgery will be unpredictable.
- When blood supply to the site is affected as in the case of radiation therapy, which will lead to compromised blood supply.
- In the case of extensive and aggressive pathological lesion, which have higher chances of recurrence.
Functions of obturator
- It serves as levin tube for feeding purpose. 
- Helps to keep the wound or defective area clean.
- It can enhance the healing of traumatic or postsurgical defects.
- It re-establishes the palatal contour and/or soft palate, which can be helpful to restore speech of the patient
- In important area of esthetics, the obturator can be used to correct lip and cheek positions.
- It can benefit the morale of patient with maxillary defects.
- It improves mastication and deglutition.
- It prevents the flow of exudates into the mouth.
- The obturator can be used as stent to the dressings or packs postsurgically in maxillary resections.
| Diagnosis and Treatment Planning|| |
Like all other specialty of dentistry, maxillofacial prosthodontics also requires careful diagnosis and treatment planning. Basically, treatment of maxillofacial defects involves a multidisciplinary approach. The rehabilitation team involves oral and maxillofacial surgeon, plastic and reconstructive surgeon, oral and maxillofacial prosthodontist, oral pathologist, maxillofacial radiologist, and psychiatrist. Proper communication between the members of team is mandatory for successful management.  The contemporary radiological investigations such as computerized tomography scan, 3D CT scan, cone beam computerized tomography scan, and magnetic resonance imaging are mandatory for proper diagnosis and treatment planning of such cases. Histological examination may provide information related to the nature of the basic pathology.
| The Surgeon and Prosthodontist Relationship|| |
For preoperative treatment planning, consultation with the surgeon is often helpful. The detailed plan for rehabilitation of the patient should be prepared. The requirement of any temporary and/or permanent prosthesis should be evaluated preoperatively. The prosthodontist will help the surgeon by advising about the presence of dental diseases and if present, the nature of the same. The prosthodontist will prepare surgical stents and immediate prosthesis, which will aid in recovery of the patient. During joint consultation, the prosthodontist and surgeon should discuss about the tentative line of resection and type of prosthesis to be used.
When insertion of stent or prosthesis has been planned at the time of surgery, the trained prosthodontist should be present at the time of operation. Intraoperatively, the maxillofacial prosthodontist may modify the prefabricated prosthesis using cold cure acrylic resin and other materials.
Postoperatively, the surgeon will evaluate the healing of surgical wound and depending on that will advise for the time for fabrication of the prosthesis. During postoperative healing, the wound should not be disturbed which may affect the healing adversely. On the other hand, fabrication of some stabilizing prosthesis may help in rapid healing. 
| Types of Obturators|| |
The majority of acquired palatal defects are due to surgical removal of tumor involving palate, nose, and paranasal sinuses. The resection is planned according to size, extent, location, and behavior of the neoplasm. The postsurgical treatment plan for the patient requiring prosthodontic rehabilitation can be divided into three phases. Depending on time between surgery and insertion of prosthesis, three types of obturators are used for rehabilitation of the patient. All three obturators have different rationale and different requirements.
The feeding plate is also a type of obturator which is used to close defect created by cleft palate. Its use is followed by surgical intervention to close the congenital defect.
The velopharyngeal prosthesis is a type of obturator, which extends to cover the defect of soft palate. It rehabilitates patient's speech and will prevent regurgitation during swallowing.
| Surgical Obturator|| |
It is a plate-type appliance. It is clear acrylic plate prepared from the preoperative impression cast and is inserted at the time of resection of the maxilla in the operating room. The basic purpose of this prosthesis is to restore form and function immediately after surgery and promote healing of the surgical wound.
| Advantages of Surgical Obturator|| |
The surgical obturator restores patient's oral functions, speech, mastication, and deglutition, soon after the surgery.
Rehabilitation with the surgical obturator will help the patient psychologically and will reassure the patient. Moreover, replacement of anterior artificial teeth will also have positive impact on psychology of the patient.
The surgical obturator helps in reducing chances of bleeding postoperatively.
The obturator also maintains the packing in a proper position, which will maintain the skin graft in position.
Properly fitting obturator will prevent oral contamination and reduces the chances of postoperative infection.
It restores the palatal contour and covers the defect.
| Features of Surgical Obturator|| |
The obturator should be simple, lightweight, and inexpensive. Usually, it is prepared from clear acrylic.  The oral part of the prosthesis should be contoured according to oral anatomy. On the defect side, it should terminate short of the graft-mucosal junction. On the oral side of the prosthesis, posterior teeth should not be replaced on defect side until surgical wound is well organized. And even if posterior teeth are replaced, they should be kept out of the occlusion. Pravinkumar  in 2011 has described the method for immediate surgical obturator, which has original anatomical contour. Replacement of anterior teeth with prosthesis can have psychological advantages. On the defect side, it should have wire loop to carry gutta-percha or impression compound.
| Retention of the Surgical Obturator|| |
For dentate patients
In cases with small defect, the prosthesis can be retained by clasp on the remaining teeth. However in the case of large defect, wiring of the prosthesis with remaining teeth is required.
For edentate patients
In such cases, careful examination of the patient's present prosthesis is critical. After correction of extension with autopolymerizing resin, the prosthesis is relined with intermediate reline material. At the time of surgery, the prosthesis is wired to alveolar ridge or zygomatic arches and/or anterior nasal spine. Sometimes, frontal and circumzygomatic wiring are also employed. The prosthesis for the small defect can be retained by adhesion, peripheral seal that is reduced than the optimal, and tongue control. The surgical obturator should not be removed for 7-10 days.  Bohle et al. have demonstrated the use of mini-dental implant for retention and stabilization of immediate surgical obturator.
| Temporary Obturator|| |
This obturator is prepared after initial healing of the surgical wound. It is fabricated from the postsurgical impression cast. On the oral side, the prosthesis will have contour for palate and alveolar ridge and usually without teeth. On the defect side, the prosthesis will have bulb, projecting into the defect. The bulb part is to be lined with soft lining material, which is to be changed at regular intervals. Because of the porosity of the lining materials, they are susceptible to bacterial contamination that can lead to undesirable odors and mucosal irritation. Usually, the patient reviewed at interval of every 2 weeks. During this time, the soft tissue may show rapid changes, which may require frequent adjustments in the prosthesis.
During this time period, the prosthesis may increase in weight and bulk because of repeated addition of the lining material. Moreover, retention and stability of such prosthesis may be compromised. These require the fabrication of definitive prosthesis. Definitive prosthesis is to be fabricated after complete healing of the surgical wound and when the patient's physical and emotional conditions permit procedures to be undertaken for prosthesis fabrication
| Definitive Prosthesis|| |
Last active phase of rehabilitation of maxillary defect patients includes fabrication of definitive prosthesis. The definitive prosthesis has different rationale and designing aspects when compared to others. The timing for fabrication of such prosthesis depends on many factors. The factors to be considered are the following:
- Size and location of the defect
- Healing of surgical wound
- Prognosis of tumor recurrence control
- Effectiveness of present obturator.
Usually, fabrication can be carried out at around 6 months after surgery. As far as remodeling of tissue at the wound is concern, it can continue for 1 year after the surgery. The amount of remodeling will be highest in soft tissue, whereas bony tissue shows less amount of remodeling.
| Designing Features|| |
The definitive prosthesis should have proper contour on oral side to restore the anatomy and on defect side to obturate the defect. The obturator will have false teeth, false palate, and ridge and bulb to fill the defect.  The defect part is to be rehabilitated with part of prosthesis known as bulb.
| Designing of 'Bulb'|| |
In the case of small size defect, prosthesis without bulb part can be prepared. In the case of large defect, there will be need to fill the defect by preparing obturator with bulb.
Wu and Schaaf  reported that the weight reduction of hollow-type obturator prostheses ranged from 6.55% to 33.06%, depending on the size of the defect. It also helps in resonance for speech production. The hollow bulb prosthesis will be more comfortable for the patient. The bulb will provide support to facial soft tissue and helps in restoring facial form. The closed bulb design is more commonly advocated when compared to open design. In the case of restricted mouth opening, size of the bulb should not interfere with insertion of the prosthesis. One more function of the bulb is to provide support to the content of the orbit to prevent ophthalmic complication.
| Designing of oral part|| |
The oral part of the definitive prosthesis should restore patients form and function. The oral part will carry teeth, the posteriors for mastication, and the anteriors for esthetic. In the case of the edentulous patient, the oral part will be more like complete denture. For partially edentulous cases, the design will be comparable to removable partial denture and will more commonly have the base metal framework.
To simplify the designing of the metal framework, Aramany has classified the maxillary defects into six classes based on relationship of the defect area to the remaining abutment teeth. To review, according to Aramany's classification:
In this, resection performed along the midline of the maxilla and the teeth are maintained on one side of the arch. This is the most common type of maxillary defect.
In this type, the defect is unilateral retaining the anterior teeth on contralateral side. This type of defect is basically modification of classical maxillectomy. It is more favored than the classical maxillectomy.
The palatal defect occurs in the central portion of the hard palate and may involve a part of soft palate. In such cases, the majority of the teeth can be saved and designing of such prosthesis is less complicated.
Such defects cross the midline and involve both sides of maxilla. In these types of defect, the remaining teeth will be few in number and may create a unique design problem similar to the unilateral design of conventional removable partial dentures.
In such cases, the bilateral defect lies behind the remaining abutment teeth. Such defects require splinting of remaining abutment teeth.
It is a rare type of defect that lies anterior to the remaining teeth. This type of defect is more common because of trauma or congenital defects and less commonly due to planned surgical intervention.
| Techniques for Obturator Fabrication|| |
Review of the literature reveals numerous methods for fabrication of the hollow bulb obturator. The hollow bulb obturator is used widely for rehabilitation of maxillectomy patients.
Depending on conditions and requirements, many authors have advocated various modifications in the technique and designing.
Payne,  in 1965, described a technique to fabricate inflatable obturator using a balloon. Parr and Gardner  used swing lock design for obturator fabrication. Polyzois  used light-cured denture base resin and a resilient liner for obturator in 1992. Penn et al. gave an obturator fabrication technique where the line of resection is questionable. In 1997, Wang and Hirsch  described refining of hollow obturator with light-activated resin. The method for obturator fabrication with fluid resin was described by Browning and Kinderknecht  in 1984. Grossmann and Madjar  have practiced resin-bonded attachments for maxillary obturator retention in 2004.
In cases with extensive defect of maxilla, retention of the prosthesis may be compromised. In such cases, Kreissl et al. have suggested the use of zygomatic implants for retention of the prosthesis.
With development in computer technology, now it is possible to fabricate the maxillary prosthesis for the patient with greater accuracy. Such methods use modern manufacturing methods and medical imaging technology. The stereolithography and rapid prototyping can make customized maxillary prosthesis that can be used as implant and placed in position by a surgical procedure. In this method, 3D CT data of the patient will be collected in the system. All these data will be transferred to manufacturing facility. The rapid prototyping manufacturing method now can prepare model of the patient's skull and desired prosthesis. Further processing can provide definitive prosthesis, which will have greater accuracy and better rehabilitation of the defect.
| Summary|| |
The management of the patient with maxillectomy requires a multidisciplinary approach. The contemporary materials and techniques for obturator prosthesis can provide solution for various clinical conditions. Depending on the case, the operator should select the best suitable material and technique for successful rehabilitation and thereby improving quality of life of the patient.
| References|| |
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