A radio-opaque denture material

Prosthodontic Applications of Polymethyl Methacrylate (PMMA): An Update

A wide range of polymers are commonly used for various applications in prosthodontics. Polymethyl methacrylate (PMMA) is commonly used for prosthetic dental applications, including the fabrication of artificial teeth, denture bases, dentures, obturators, orthodontic retainers, temporary or provisional crowns, and for the repair of dental prostheses. Additional dental applications of PMMA include occlusal splints, printed or milled casts, dies for treatment planning, and the embedding of tooth specimens for research purposes. The unique properties of PMMA, such as its low density, aesthetics, cost-effectiveness, ease of manipulation, and tailorable physical and mechanical properties, make it a suitable and popular biomaterial for these dental applications. To further improve the properties (thermal properties, water sorption, solubility, impact strength, flexural strength) of PMMA, several chemical modifications and mechanical reinforcement techniques using various types of fibers, nanoparticles, and nanotubes have been reported recently. The present article comprehensively reviews various aspects and properties of PMMA biomaterials, mainly for prosthodontic applications. In addition, recent updates and modifications to enhance the physical and mechanical properties of PMMA are also discussed.

Accidental ingestion of molar band and its management: maintenance is better than management

Ingestion of a broken part of fixed orthodontic appliance is a potential complication during orthodontic treatment. We report a case of accidental ingestion of molar band and its subsequent diagnosis followed by endoscopic retrieval method. Although prevention of such incidence is the best method at the same time management of such an event is also crucial. The objective of this paper is to draw attention to the potentially serious complications that can occur if preventive techniques are not practiced and also the management of such event.

Unsuspected swallowing of a partial denture

We report a case of a swallowed partial denture in a 51-year-old man who presented with progressive dysphagia, odynophagia, and fevers. Imaging studies were initially interpreted as supraglottitis with laryngeal inflammation, which was confirmed by direct visualization with flexible endoscopy. Despite appropriate therapy, the patient's symptoms persisted and rigid laryngoscopy was performed, which revealed a partial denture in the hypopharynx and upper esophagus. The subtle imaging appearance of a swallowed denture is discussed.

Swallowed partial dentures

Swallowed or inhaled partial dentures can present a diagnostic challenge. Three new cases are described, one of them near-fatal because of vascular erosion and haemorrhage. The published work points to the importance of good design and proper maintenance. The key to early recognition is awareness of the hazard by denture-wearers, carers and clinicians.

Swallowed partial dentures

Swallowed or inhaled partial dentures can present a diagnostic challenge. Three new cases are described, one of them near-fatal because of vascular erosion and haemorrhage. The published work points to the importance of good design and proper maintenance. The key to early recognition is awareness of the hazard by denture-wearers, carers and clinicians.

Hazards of orthodontics appliances and the oropharynx

Occasionally orthodontic appliances or parts of orthodontic appliances have caused problems with either the airway or the gastrointestinal tract. The type of appliances that have caused problems and their clinical management are discussed. A case is described in which an upper removable appliance with inadequate retention became lodged in a patient's pharynx lacerating the palatine tonsils. Suggestions are made to try and avoid the problems that were encountered in this case and others reported in the literature in patients undergoing orthodontic treatment.

Radiopaque polymeric materials for medical applications. Current aspects of biomaterial research

The aim of this review is to give an overview and some insight into different radiopaque polymeric materials that are currently used as medical implants or inserts. The advantages and limitations of each radiopaque polymeric material are summarized. The main method used to make medical implants radiologically visible is based on blending polymers with conventional radiopaque agents, blends which usually are a physical mixture of acrylic derivatives and inorganic salts. Other methods reported involve either the formation of single-phase radiopaque polymer salt complexes somehow preventing the release of the radiopacifying element by entrapment of the complex in a crosslinked network, or radiopaque polymerized monomers characterized by a radiopacifying element associated with the monomer unit prior to polymerization. In the near future, research will certainly concentrate on biocompatible radiopaque polymers with covalently bound opaque elements leading to stable polymers with properties equivalent to the nonopaque, parent polymer.

The use of computed tomography in the detection of radiolucent denture base material in the chest

With the introduction of acrylic resin denture base materials to the dental profession, radiolucency was recognized as a significant deficiency at an early stage. Continuous research into the production of a radiopaque material has been directed at including radiopaque glasses, salts or metals powders in an otherwise radiolucent polymer. However, the majority of new dentures are still made in radiolucent material which is notoriously difficult to locate by conventional radiography and reports continue to appear relating to the inhalation or ingestion of dentures (or fragments of them), occasionally leading to the death of the patient. Advances in radiographic techniques and equipment have seen the development of computed tomography (CT). This has proved invaluable as a diagnostic aid for disease and therapy but little attention appears to have been given to the use of this sophisticated technique in the detection of foreign bodies, in particular those of dental origin. This study investigates the use of CT in the detection of radiolucent denture base material. The results suggest that CT has substantial advantages over conventional radiography in the detection of this material and should be considered as a valuable diagnostic aid in those patients thought to have inhaled dentures or fragments of dentures.

A method of determining the radiopacity of dental materials and foreign bodies

The desirability of radiopacity in dental materials and other materials that may become foreign bodies is documented. No simple, reliable methods are available for the determination of radiopacity, and no standard specifications have been devised with regard to the radiopacity of dental materials. A method that enables radiopacity to be determined is described. The theoretical aspects of radiopacity in relation to the method are considered. Possible applications of this method in the development of standards for radiopacity are suggested.