Microstomia in a maxillectomy patient: A prosthetic challenge

The provision of a satisfactory denture in case of reduced stomal inlet has always been a trouble for the patient and a challenge to the prosthodontist. Fabrication of complete and removable partial denture prosthesis requires accurate diagnostic impression and diagnostic casts for the development of custom trays and final impression. The decreased mouth opening, technically called "Microstomia," poses problems in tray selection, impression making, jaw records and denture insertion. The causes for microstomia are numerous, one major cause being the after-effect of radiation therapy. Whatever the cause, the ability to make impressions and jaw records becomes taxing. A variety of impression techniques using modifications in the nature of the tray and impression materials are required. The present case report highlights an innovative and different aspect of impression making and fabrication of an obturator prosthesis for a microstomic patient who underwent maxillectomy.     

One clinical visit for a multiple implant restoration master cast fabrication

The making of a one-piece, long-span, implant-supported prosthesis with conventional procedures frequently has difficulties associated with the accuracy of fit. This article presents a clinical and laboratory procedure for making an accurate implant working cast that facilitates fabrication of the casting on the master cast. The procedure demonstrates the process of sectioning and rejoining of the resin between the transfer copings and then pouring the impression by first joining the analogs alone with impression plaster, sectioning it, and rejoining it again to stabilize the analogs, and finally, using dental stone to pour the impression. Clinical, radiographic, and laboratory (optical microscope) measurements for one clinical implant restoration confirm the accuracy of fit of this one prosthesis made with this procedure. Its advantage is that it can allow fabrication of the final casting on the cast, thereby eliminating the clinical time necessary to obtain repetitive solder indexes, and thus minimizing inconvenience to the patient. (J Prosthet Dent 1997;78:550-3.)     

Poly(methylmethacrylate) Microwave Processing: A Technique Paper

Microwave processing of a wax trial denture into a poly(methylmethacrylate) provides a viable alternative to conventional compression, injection, and digital techniques. This article briefly describes a processing technique that yields a complete dental prosthesis in under two hours using a combination of modern materials designed to reduce working and setting times without compromising the quality of the final prosthesis.     

Anatomy and procedure for making an impression for a removable complete denture

Making an impression of an edentulous jaw is an essential part of producing a removable complete denture, because the proper functioning of the denture is partially dependent on the volume and form of the alveolar ridge and the surrounding soft tissue, in particular the musculature. Before the impression of the maxillary and mandibular jaw is made, insight into the anatomy of the maxilla and the mandible as well as the soft oral tissues is also essential. With respect to this, a 5-phase approach for the impression-making procedure is introduced, which gives guidelines for the fabrication of the preliminary impression, the preliminary cast, the individual impression tray, the final impression and the final cast. In each phase, the concern is to achieve the best possible stability of the denture. Adequate stability can only be achieved by determining the denture borders accurately.     

Technique for achieving a passive framework fit: a clinical case report

The clinical application of a 4-step technique for achieving the passive fit of an implant-supported cast bar or framework is reported. Implant-level transfers were attached, splinted intraorally with pattern resin, picked up in an open-tray elastomeric impression, and used to fabricate a working cast containing implant analogs. A light-cured template was used to verify master cast accuracy. A ceramometal fixed partial denture restoration was fabricated on the working cast with a preliminary try-in of the cast metal framework. A passive prosthesis fit was achieved. Failure to create an accurate working cast can distort the intended fit of a cast framework on the abutments in the patient's mouth. Optimal positioning of the implant analog in the master cast depends on (1) the transfer technique and (2) the ability of the system to maintain precise rotational orientation of the transfer components. The splinted transfer technique developed 20 years ago has sometimes been effective in improving the accuracy of framework fit with external hexagon implant-abutment connections, but it has not been documented with newer implant-abutment connections. Techniques for reestablishing master cast accuracy and correcting the superstructure are presented. The use of the presented technique resulted in a passive-fitting framework.     

Implant position record and implant position cast: minimizing errors, procedures and patient visits in the fabrication of the milled-bar prosthesis

This article describes a new rationale and method involved in the fabrication of a patient detachable prosthesis supported by a milled bar. This simple procedure improves prosthesis retention. The overdenture is processed directly over a milled bar, which provides an intimate relation between the bar and the acrylic resin denture base to create resistance against rotational and lateral forces acting on the prosthesis. Incorporating simple and predictable attachments, with low maintenance needs, controls resistance to dislodgment along the path of insertion of the prosthesis. The concepts used in the fabrication of the milled bar include an implant position record (IPR) and an implant position cast (IPC) to reduce the need for time-consuming procedures, such as sectioning the cast bar and soldering it to make it fit the abutments. This procedure also reduces the number of patient visits required of the completion of the prosthesis.     

The transmandibular implant: prosthodontic treatment considerations.

The transmandibular implant (TMI) is a type of transosteal implant designed for use in the edentulous mandible. The implant is composed of a gold-based alloy. The TMI is a loaded implant in that the prosthesis is supported by the implant. A transitional type of prosthesis, for insertion following surgery can be made either by altering the patient's existing mandibular complete denture or by making a new denture. The completed prosthesis is retained by clips held in the mandibular denture with autopolymerizing acrylic resin. The clips engage Dolder bar segments, which are a part of the implant suprastructure, and provide the necessary retention for the mandibular complete denture.     

Evaluation of interarch space for implant restorations in edentulous patients: A laboratory technique

This article describes a laboratory procedure for the visual evaluation of interarch space and its effect on implant prosthesis design. The method is applicable to patients presenting with completely edentulous arches. Silicone impression material is used to form a resilient cast and an external mold from an existing denture. The denture is duplicated using autopolymerizing acrylic resin. The duplicate denture and resilient cast are mounted on an articulator. Spatial relationships of anatomic landmarks can be evaluated, and a quantitative evaluation of available space can be made. The duplicate denture can also be used as a surgical template to direct implant placement. Reference tables are provided to serve as guidelines in the correlation between available space and minimum space required for various implant-assisted restorations.     

Laboratory fabrication of gold occlusal surfaces for removable and implant-supported prostheses

This article describes a technique for fabricating prosthetic teeth with gold occlusal surfaces for removable or implant-supported prostheses. Following a successful wax try-in appointment, the denture teeth used in the prosthesis are invested in a denture flask. After deflasking, the gingival 2/3 of the denture teeth are trimmed away. The remaining occlusal portions of the teeth are invested in a gypsum-bonded investment and cast in a type III gold alloy. After polishing, the castings are repositioned back into their respective sites in the flask. An acrylic resin of an appropriate shade is mixed and packed in the flask. Once the acrylic resin is processed to the metal occlusal surfaces, the individual teeth are removed from the flask and polished. Then the finished teeth are reinserted in the wax trial denture, the occlusion is refined, the final wax-up is completed, and the prosthesis is processed.     

Early functional loading in the fully edentulous mandible after mandibular resection and reconstruction due to an ameloblastoma: case report

Background: Immediate or early functional loading of implants in fully edentulous mandibles can enhance patient comfort and the ability to masticate within a few days after implant placement. Recently there has been evidence that this method of restoring edentulous mandibles is predictable. Purpose: The goal of this case report is to present the treatment of a patient diagnosed with a large ameloblastoma in the mandible. After removal of the tumor and mandibular reconstruction, the patient had complete anesthesia in the right mandible, with an alveolar ridge deformity. Methods: Two years after removal of an ameloblastoma in the right mandibluar sextant, five implants were installed between the mental foramina. One implant was installed for safety reasons in the event one of the others was lost. This implant remains buried. A denture was used as a drilling guide. Abutments were attached to the implants, and impression copings were fixed to the abutments. The denture was used for the “pickup” impression. Flaps were sutured, maintaining exposure of the abutments. In the laboratory, gold cylinders were heat cured to the tissue side of the denture. The cylinders were attached to the cast with laboratory screws. The gold cylinders were heat cured to the intaglio side of the denture. Five days after implant placement, the nonmetal reinforced acrylic denture was fixed to the implants with laboratory screws. The bridge is removed annually, and the implants are examined for mobility and periapical radiographs are taken. Results: The patient has worn the prosthesis for 2.5 years without loss of implants and without breakage of the nonmetal reinforced denture. At 2.5 years the implants are stable, implant sites demonstrate stable crestal bone, and the patient is eating comfortably and without limitations. Conclusion: Early functional loading of implants in the edentulous mandible may offer patients the option of wearing implant‐supported prosthesis immediately or shortly after implant insertion.     

Recording and reproducing cast orientation by using an implant impression coping and implant analog: A dental technique

For the fabrication of a removable partial denture, the orientation of a definitive cast should be recorded and reproduced to indicate the most desirable path of placement and undercut areas. This article describes a straightforward and accurate method of recording and reproducing the cast orientation by using an implant impression coping and an implant analog.     

Fabricating an Accurate Implant Master Cast: A Technique Report

The technique for fabricating an accurate implant master cast following the 12‐week healing period after Teeth in a Day® dental implant surgery is detailed. The clinical, functional, and esthetic details captured during the final master impression are vital to creating an accurate master cast. This technique uses the properties of the all‐acrylic resin interim prosthesis to capture these details. This impression captures the relationship between the remodeled soft tissue and the interim prosthesis. This provides the laboratory technician with an accurate orientation of the implant replicas in the master cast with which a passive fitting restoration can be fabricated.     

One-step implant index verification and maxillomandibular relationship

Before definitive fabrication of an implant-supported prosthesis, the accurate positioning of the fixtures or abutment replicas on the working master cast must be verified. In addition, the implant master cast must be accurately mounted against the opposing cast. The purpose of this paper is to demonstrate a technique that combines the verification index and a maxillomandibular relationship into one step, with an accurate technique to record the relationship.     

A modified technique and simplified laboratory procedure for ocular prosthesis fabrication

PurposeIn many cases dentist tries to satisfy the patient with stock prosthesis that comes in standard sizes, shapes and colors. However, most of the patients complain of discomfort even after appropriate adjustment because of insufficient adaptation to underlying soft tissues. The rehabilitation of a patient with loss of eye as a result of congenital defect, pathology or accidental trauma is a challenge in terms of re-establishment of the esthetics of the patient. The purpose of this technical procedure is to provide a well fitting prosthesis to the patient, reducing the number of laboratory steps and appointments for fabrication of ocular prosthesis.MethodA suitable stock eye shell was modified to fit the eye socket, followed by relining with low fusing compound and making a final impression with polyvinyl siloxane impression material. The impression was poured in die stone, flasking procedure was accomplished. After dewaxing, molten wax was flown in the lower half of the flask followed by repositioning of the upper half. The flask was reopened, the stock eye shell along with the hardened wax on tissue surface was tried in the patient's eye. Finally processing was done.ConclusionThis technique describes an impression procedure, followed by a wax pattern try-in in the same appointment and also the detailed laboratory procedure for fabrication of the ocular prosthesis, taking into consideration positioning of iris as a result enhancing the esthetic appearance of the patient.     

Fabrication of a Duplicate Denture From an Existing Complete Denture

A technique is presented that describes the fabrication of a duplicate denture using the patient's existing complete denture. This procedure enables the practitioner to offer patients an alternative to being without a denture during a laboratory reline of an existing denture. A vinyl polysiloxane impression material is used to impress the polished surface of the existing denture as well as to block out undercuts on the impression surface of the denture before pouring a stone cast. Because of the stability of the impression material used, most of the laboratory procedures can be accomplished separate from the clinical appointment.     

Alternative prosthodontic technique for tissue-integrated prostheses

This modified technique for fabrication of tissue-integrated prostheses saves valuable clinical time for the dentist and treatment time for the patient. The technique differs in that a modified denture is placed in the mouth the day of the second operation, impression copings are eliminated at the final impression, the framework is fabricated before jaw relation records, a high-content palladium alloy is used for the framework, the master cast is flasked similar to a complete denture technique, and the access openings are closed with a light-cured resin. Prerequisites for a tissue-integrated prosthesis are not violated and comparable results are achieved. The technique can also be used in maxillary arches and, with slight modifications, for partially edentulous patients. This technique has been used 3 years for 35 jaws in 37 patients, with 184 fixtures. Four fixtures have failed, producing a 98% success rate. All prostheses have remained continuously stable. Economy of clinical time and laboratory procedures in the prosthodontic phase increase the acceptance of osseointegration in clinical dentistry. The cooperative efforts of all disciplines will provide a greater acceptance of this treatment modality, which will enhance the patients' quality of life.     

Clinical and technical aspects of implant-supported restorations in the edentulous maxilla: the fixed partial denture design

PURPOSE: The aim of the present article was to describe the treatment planning for an implant-supported maxillary fixed prosthesis and the clinical procedure involved, including the laboratory fabrication sequence. MATERIALS AND METHODS: If patients request a fixed prosthesis to restore the edentulous maxilla, it is essential to decide as soon as possible whether this prosthesis design can satisfy the requirements of esthetics, phonetics, comfort, and function. Thus, the crucial clinical factors need to be checked during examination. Furthermore, the relationships between ideal implant angulation, available bone, and intended crown should be assessed using reformatted computed tomography. RESULTS: In patients with minimal bone resorption and limited intermaxillary space, implants can usually be placed in the prosthetically driven implant position for a fixed prosthesis. To evaluate and optimize esthetics, biology, and function, a fixed provisional restoration should be inserted for a 6-month diagnostic period. The ideal provisional then serves as a guide for the final restoration. CONCLUSION: If clinical and radiologic diagnostics indicate that an implant-supported fixed complete denture is feasible, meticulous presurgical planning, precise execution of implant positioning, and a progressive prosthetic treatment sequence are required. The ceramometal fixed implant-supported restoration can then be established in an ideally prepared and matured oral environment.     

Remount casts for removable partial dentures made in a laboratory

A remount cast for a removable partial denture can be made in the laboratory by making an elastomeric impression of the prosthesis on the cast after processing but before removing it from the cast. After the prosthesis is finished and polished it is placed in the impression, undercuts are blocked out, and a mounting cast is made.     

模型置换印模技术修复下颌游离端牙列缺损的临床研究

目的：探讨模型置换印模技术对双侧下颌游离端缺牙患者的修复效果。方法：在解剖式印模上常规制作铸造支架,在铸造支架上制作自凝暂时基板,经口内肌功能修整并制取咬合记录后于口内取功能性印模。经模型置换后常规完成义齿。结果：90.2%的患者用模型置换印模技术制作的义齿疗效良好。结论：模型置换印模作为游离端可摘部分义齿的重要功能印模方法,可以有效改善义齿修复质量。     

Expedited Record Base Fabrication Using an Irreversible Hydrocolloid Cast

The registration of a maxillomandibular relationship requires additional clinical and laboratory procedures when the mouth presents with loss of occlusal support. This procedure can be a challenge for a patient who needs urgent care or resides in a remote area. This article describes a procedure for expediting the mounting of a master cast for the fabrication of a maxillary immediate complete denture. The technique presented describes the use of a silicone record base made on an irreversible hydrocolloid cast generated from the final impression.