Abstracts:
Dental impression is an essential technique used in dentistry to obtain an accurate replica of patients’ teeth and oral tissues. This procedure is crucial in the process of planning and making dentures, crowns, bridges or other custom dental work.
Accurate dental impressions ensure a proper fit and optimal functionality of restorations, playing a crucial role in ensuring the health and beauty of patients’ smiles.
This article discusses the importance of dental impressions and describes the various techniques used in dentistry to achieve accurate and satisfactory results.
Introduction
Dental impression is a technique used in dentistry to record precise details of teeth and oral tissues. This information is used to create an exact replica of the patient’s oral cavity and tooth structures in order to fabricate custom dental work.
The importance of dental impressions
Obtaining an accurate impression is essential to ensure the correct fit and optimal functionality of dental work. An accurate impression ensures that dentures, crowns or dental bridges are well fitted in the oral cavity, avoiding problems of incorrect fit, discomfort or dysfunction.
In addition, a quality dental impression plays a vital role in the aesthetics of the patient’s smile. It allows for customized restorations that fit perfectly in harmony with the patient’s facial structure and natural tooth color.
Dental impression techniques
There are several techniques available for obtaining dental impressions, each with its advantages and limitations. Here are some of the most commonly used techniques:
Impression with dental plaster:
This technique involves applying an impression paste directly to the teeth and oral tissues. Impression pastes can be made of various materials, such as silicone or polyether.
This method is effective and provides accurate detail, but can be uncomfortable for patients and requires a period of solidification.
Alginate impression:
Alginate is an elastic material commonly used for preliminary impressions. It is easy to use, affordable and produces satisfactory results for temporary work or in cases where exact detail is not required.
Dental digital impression:
Digital technology has revolutionized dentistry and digital impressions are becoming increasingly popular. This technique involves using an intraoral scanner to create a three-dimensional image of teeth and oral tissues. Digital impressions are fast, accurate and comfortable for patients, eliminating the need for traditional impression materials.
The impression is an exact reproduction, in negative, of all the elements of the prosthetic field.
The effectiveness of prosthetic treatment with any type of fixed or removable prosthesis depends largely on the degree of accuracy of the dental impression.
For a fixed restoration, the following elements are sent to the dental laboratory:
The abutment teeth with: preparation surfaces, cervical preparation boundary, remaining unprepared areas of the abutment teeth, marginal periodontium shape
Edentulous ridge surfaces
Surfaces of neighboring teeth of future prosthetic restorations
Surfaces of antagonist teeth of future restorations
Mandibular-maxillary occlusal relationship
Impressions are used for various purposes: making working models that allow transferring the finest details of the prosthetic field to the dental laboratory, obtaining study models that facilitate diagnosis and treatment planning, obtaining document models and making duplicate models useful in the course of modern laboratory technologies.
Features
The fundamental characteristic of an impression is its accuracy, thus ensuring one of the essential conditions for obtaining an accurate model. The accuracy of the model is also influenced by other conditions such as: the way the impression is stored and handled, the type of material from which the model is made, the time chosen for casting the model, the technique of obtaining the model.
Classification
Impression materials are classified into:
rigid and semi-rigid irreversible materials (gypsum, ZOE paste)
reversible rigid materials (waxes, bioplastic materials)
reversible elastic materials (reversible hydrocolloids)
irreversible elastic materials (irreversible hydrocolloids, synthetic elastomers: polysulfides, silicones, polyethers)
In current practice, irreversible elastic materials are mainly used. Irreversible hydrocolloids (alginates) are mainly used for the impression of the antagonistic arch.
Properties
The properties of elastic impression materials are: surface wettability, thixotropic, viscosity, mechanical strength, permanent deformation, shrinkage and dimensional stability.
Impression trays or impression ingots are rigid supports in which impression materials are applied; only with their help, materials can be inserted into the denture field.
The role of the impression of prepared teeth is to faithfully represent their “negative”. To serve as a “mold” in the casting of the model.
Due to the fact that cast prosthetic restorations, from inlays and single crowns to large fixed partial dentures, are made only indirectly – on the model in the dental laboratory, the perfect fit of prosthetic restorations is only achieved when the model reflects as accurately as possible the morphology of the prosthetic field being cast.
Conclusion
Dental impressions are an essential step in the process of planning and fabricating custom dental work. This technique provides detailed and accurate information about patients’ oral cavities, ensuring a correct fit, optimal functionality and superior aesthetics. Modern technologies, such as digital impressions, further enhance this process, providing fast and accurate results.
In conclusion, dental impressions play a vital role in dentistry, helping to improve the quality of dental work and patient satisfaction. By using appropriate impression techniques, dentists can ensure high-quality dental care and successful results in restoring and improving dental health.