obturator

Obturators

Forces acting on obturator
Vertical dislodging force (gravity)Occlusal vertical forceTorque or rotational forceLateral forceAnterior – posterior force

A common feature of MFP & obturators  is that all framework design should be dictated by basic prosthodontic principles of design, that include: Broad stress distribution, Cross-arch stabilization with use of a rigid major connector.Use double retentive &/or double stabilized action clasps, to minimize the dislodging functional forces.3. Replacement tooth positions that optimize prosthesis stability and functional needs (minimum No. with great benefits). Modifications to these principles are determined on an individual basis and are greatly influenced by unique residual tissue characteristics and mandibular movement dynamics.

Postoperative Malocclusion

Deviates to surgical side.


Objectives of cleft palate & lip prosthesis:Speech – lack of valvopharyngeal closure leads to escape of air through the nose (nasal speech)Deglutition – greatly impede the feeding, and escape of fluids through the nose takes place .Mastication – impaired due to escape of food through the nasal cavity and due to missing teeth and malocclusion .

Esthetics – is effected seriously especially in cleft palate and lip. Deterioration of the general healthPsychological trauma .Recurrent infection of the air ways and middle ear .

Management of cleft lip and palate Include the following: Surgical closure It is the treatment of choice for palatal cleft closure. It superior to prosthetic closure by obturator. If cleft involves the lip, it is advisable to repair it as early as possible (6 wks. after birth) to facilitate feeding and improve appearance. Surgical closure of palatal cleft is better to be done before the end of the second year of age.



Three phases of prosthodontic treatment, includes: Surgical phace  surgical procedures + Immediate obturator. Transitional phase  Temporary obturator.Functional phase  Definitive obturator.

Immediate obturator

Temporary obturator
Definitive obturator

Obturator

Restores oro-nasal partition. At times can be added to prior dentures.


CONSTRUCTION:Presurgical Impression  construction of the cast models.With the help of the surgeon determine the area to be removed on the cast .The appliance is constructed as a plate to close the operation site.Prepared cast is waxed, processed using either heat or cold curing resin and wire clasps to retain the obturator.

During operation eradication of the involved area, and surgical cavity is filled with surgical pack.We can say, it is simple plate with no teeth and constructed before surgery to be inserted immediately after surgery.After 5 – 7 days, the surgical obturator and packing are removed. The defect area is cleaned with mineral oil and the surgical obturator is adjusted and relined with tissue conditioner material.

The patient then returns weekly for adjustment and change relining material. Finally, the relined obturator is duplicated in heat cured acrylic. resin resulting in interim obturator


Palatal screwing: The palatal bone screw can be placed through a mid palate hole predrilled through the acrylic resin base plate in the mid palate at the anterior peak of the palatal vault.

13- to 16-mm palatal bone screw, angled posteriorly for retention obturator prosthesis.
Methods for retention of Immediate (surgical) Obturator, are:



Suturing: Sutures placed at the periphery of the prosthesis can be sutured into the soft tissues of the vestibule.
Circumzygomatic wire: retention wires are passed over the zygomatic arch and threaded through two bilateral holes placed in the premolar area of the baseplate flange. This technique is the most invasive and has greatest morbidity when removing the wires in the clinical setting. It is not commonly used.

Clasping. Inter dental wiring. Mini-implant Adhesive. Anatomical undercuts within the confines of defect. Magnets. Osseointegrated titanium implants. Facial prosthesis connection to upper denture.


Use of the existing maxillary denture: Some texts suggest using the patient's existing denture for the surgical obturator and considered as interim obturator prosthesis, but there are disadvantages to using the existing denture at the surgical or interim phase. If the maxillary denture is ill-fitting preoperatively, it will be necessary to reline the denture prior to surgery.


Temporary (Transitional or Interim) Obturator: Constructed few days after operation to help in restoring oro-nasal function. Those prosthesis which are placed immediately after packing removal, used until tissue contracture is minimal and prior to definitive obturator placement3weeks after maxillary resection, wound had started re-epithelizing. At this stage interim prosthesis was given Or Within 1 – 2 weeks.

Carries teeth and stays 3-6 months. Making impression is complicated by presence of the wound and presence of the defect.


The defect is packed with gauze dipped in Vaseline to the level of the remaining tissue, then impression is taken with modified stock tray using elastic impression material. The steps of construction are the same as in immediate obturator.

Function helps in restoring: To restore deglutition and speech by restoring palatal counters. Separating nasal cavity, maxillary sinus and naso pharynx from oral cavity. Esthetics improvments. Prevent wound contamination.prevent occlusal loading in the region of resection during the early stage of healing.

DEFITIVE OBTURATOR

Definitive Obturator: It is a final prosthetic management construction after complete healing of the operation site, usually wear after 3-6 months after the surgical operation. Types of Definitive obturators: Hollow bulb (Closed). Roofless (Open bulb).


Open/close obturator
Open Patient complains of food, fluid, and mucous accumulation > bad odor and altered taste sensation Benefit to patient > reduced wt. , ease of fabrication, increased speech intelligibility Closed Prevent food and fluid collection , reduced air space Allows maximum extension

Preparation of the mouth for obturator: Extract hopeless teeth. Periodontal therapy. Restore carious teeth.
DEFITIVE OBTURATOR
Construction: Select stock tray, modified with wax according to the size and shape of the defect. Partially, pack the defect with Vaseline gauze, then do primary impression using alginate.

Under cuts are lift to help in retention. Gauze can prevent broken pieces of alginate from escaping into the defect. Construct sp. Trays and do final impression using alginate or rubber base impression material. Outline the master cast to mark the bearing area, blocking severe undercut, leaving small undercut area for obturator retention.
DEFITIVE OBTURATOR


During construction of definitive obturator for better retention , support & stability the buccal border of it should articulates with scar band.
DEFITIVE OBTURATOR
Scar band  healthy healed tissue (sequamous epithelial cells) Also for better retention adhesive materials or implants (such as Zycomatic implant), can used.

The end