Denture relining: steps in the correction of removable plate prostheses

وقت القراءة ~ حوالي 5 دقائق عدد القراءات: 30413

The basis of comfortable use of removable orthopedic systems – a secure fit to the jaw. But gradually the fixation of the structure weakens, functionality decreases, there is discomfort when eating, talking. Rebasing of the prosthesis (partial, full) – involves the elimination of inaccuracies, prevention of damage to the base of the structure, restoration of accurate contact with the gums, supporting dental units. Depending on the clinical case, such a procedure is carried out in the office of a dentist or in the laboratory.

When relocation of the prosthesis is necessary

After fixation of the new prosthetic system, after the first 1-3 months of wear, relining of the denture is necessary to correct the accuracy of its fit to the mucosa. Since the teeth have been missing for some time, the jaw joint has reorganized. After the prosthetic structure is installed, the load on the jaw tissue changes. It begins to gradually atrophy, the gum sags, the bite begins to change. The denture becomes uncomfortable and the occlusion is disturbed.

Rebasing is indicated

if the structure does not fit properly in the mouth, falls out when talking, eating, presses on the gums;
in the presence of defects in the prosthetic system, due to the violation of technology in the impression or fabrication;
deterioration of the aesthetic performance of the structure;
the prosthesis has been broken, has flaws;
the shape of the alveolar process has changed, which caused instability of the prosthetic structure;
an atypical change in the height of the lower part of the face has been detected (even if the deviation is minimal from the original parameters).

Correction is required not only for removable models, but also for conventionally removable implant-supported structures. These are mostly one-stage protocols with immediate loading (all-on-4, all-on-6). After the implants have been implanted and the prosthetic system has been fitted, the load on the bone increases. This leads to increased regeneration of bone tissue, an increase in its parameters, which requires correction of the prosthetic apparatus. That is, if the bite changes, the position of the prosthetic system changes.

Methods of correction

Rebasing of a full removable prosthesis, as well as restoration of a partial design, is carried out by two methods – clinical (in the dentist’s office) and laboratory. If the construction is not sufficiently fit, the doctor can correct it in front of the patient, it takes a minimum of time. In case of significant misalignment, reduction of bite height, additional equipment will be needed, correction is carried out in the laboratory. How the rebasing of dentures is done depends on the complexity of the work, the type of prosthetic system.

Clinical method

The procedure includes the following stages of denture relocation:

assessment of the bite, occlusion, compliance of the prosthetic structure with the relief of the jaw;
fitting of the structure, filing of edge elements (lengthening, shortening);
removal of polishing from the prosthetic system, preparation of polymer mass;
distribution of the polymer composition on the treated surface of the prosthesis;
fitting of the prosthetic system to the patient, with full interlocking of the upper and lower jaw teeth (assessment of the central occlusion);
removal of excess polymer mass from the structure, polymerization of plastic (if there is a metal base, a layer of the corresponding metal is sprayed on the inner surface of the prosthesis, then the plastic mass is applied to the metal base);
immersion in hot water for final polymerization, improving bonding strength;
modeling of the marginal segment, final polymerization.

The clinical method allows you to immediately eliminate all defects, to achieve a tight fit of the prosthetic system to the gums. The method is not used in the presence of infectious-inflammatory diseases of the oral mucosa, allergy to plastic.

Laboratory method

Relocation of the denture base in the laboratory allows you to avoid the negative impact of plastic composite on the mucosa, but you will have to wait a few days for the result.

The doctor assesses the condition of the prosthetic structure, takes an impression of the patient’s teeth and sends everything to the laboratory;
a thin layer of plastic is removed from the prosthetic system, polishing is removed from the edge segment;
the required amount of plastic is applied to the structure, its borders are shaped, polished, polished, and the clamping in the central occlusion position is checked;
the finished orthopedic system is returned to the doctor, who installs it to the patient.

Among the advantages of the technique are high aesthetics of the prosthetic system, maximum adhesion of materials (base, relining polymer), absence of allergy to plastic composite. Rebasing of plate prostheses in the laboratory takes from 2 days and more. There is no adaptation to the corrected prosthetic apparatus, since the patient has previously used it.

Types of rebasing material

Correction of removable plate prostheses involves the use of the following materials:

Hard plastics – cold-curing acrylics (Protacryl, Redont), hot-curing acrylates (Etacryl, Fluorax, etc.), polymethylmethacrylate. Hard base plastics are used for rigid fixation of the orthopedic system or laboratory rebasing.
Soft composites – acrylic, silicone elastomers. They are used if the physical parameters of the orthopedic apparatus are normal, but the patient feels headaches, discomfort. Usually used for relocation of mandibular prosthetic structures.
Temporary elastics (conditioners) – polyvinylchlorides and silicone base materials are highlyelastic and are used for gentle relocation of dentures in case of systematic gingival inflammation. Elastic materials are characterized by their special softness and are intended to reduce and evenly redistribute the chewing pressure on sensitive areas of the mucosa. Temporary material should be regularly updated, as it reacts negatively to cleaning agents, is susceptible to the accumulation of bacterial plaque.

The cost of relocation of the prosthetic system depends on several parameters – the technology used, material, type (burestal, conditionally removable, removable), the size of the prosthesis, etc.

Where to go

Patients with removable orthopedic devices are recommended to come to the orthopedist every 6 months for rebasing of the structure. This should be done for preventive purposes, because due to the violation of fixation of the prosthetic system in the mouth, there may be a breakage of the structure, rapid loosening and loss of supporting teeth (in the case of partial constructions).

For prosthesis restoration in Moscow, it is most convenient to turn to the network of RUTT clinics. Rebasing is carried out with modern cushioning materials from reliable manufacturers, which guarantees the accuracy of fit of the restored structure, even distribution of chewing load, and durability of use.