Effect of palatal form on movement of teeth during processing of complete denture prosthesis: An in-vitro study

Abstract

Aim:The aim of this in-vitro study was to assess the influence of shallow and deep palatal forms on the movement of teeth during the processing of complete denture prosthesis.Materials and Methods:Maxillary casts with shallow and deep palatal forms were selected and duplicated to make 10 casts of each palatal form. Base plates were constructed and teeth were arranged in their anatomic positions. Metal pins with true apex were placed on the central groove of the right and left first molars and one on the incisive papilla area as a reference point. Casts were scanned using i-CAT Vision Q 1.9 (i-CAT cone beam 3D dental imaging system by Imaging Sciences International, PA, USA), which has 360° rotational tomography. The distances between the apices of metallic pin inserts on the teeth and fitted point of reference were recorded in buccopalatal axes at waxed up stage, after deflasking, and after finishing and polishing.Results:Results showed a statistically significant movement of teeth in shallow and deep palatal forms during all stages of complete denture processing. In shallow palatal form dentures, there was a significant tooth movement in palatal direction between Stages 1 and 2 (P ≤ 0.05) and buccal movement between Stages 2 and 3. In deep palatal form dentures, teeth showed a statistically significant (P ≤ 0.05) movement in buccal direction during all stages of denture processing.Conclusion:Teeth showed significant movement during processing of acrylic resin dentures. Overall, the movement of teeth in shallow palatal form dentures was in palatal direction, whereas in deep palatal form dentures, the movement of teeth was in buccal direction.

Comparison of the Polymerization Shrinkage of Eclipse Resin for Prostheses with Conventional Acrylic Resins

“…In addition, in the study conducted by Babu et al (2016), concluded that in all fabricated prosthetic bases, the posterior palatal sealing area was the least dimensionally stable region and that denture bases fabricated using the long curing cycle would produce the most stable PMMA denture bases. However, in our study, the opposite happened: the lucitone resin that has the longest curing cycle showed greater dimensional change.…”

Efecto de combinación de materiales de inclusión a diferentes presiones sobre movilidad de dientes artificiales durante el procesamiento protésico

“…Los resultados obtenidos muestran diferencia entre los materiales probados, evidenciando que la silicona a 1 000 kg de fuerza mostró mayor estabilidad, asociada a una mayor estabilidad a la contracción 16 de la silicona empleada como revestimiento, independientemente de la técnica de polimerización empleada 23 . Con respecto al yeso su mayor capacidad de retención de humedad puede explicar los mayores valores de distorsión 24 , sobre todo cuando fue aplicado a una fuerza de 1 000 kg de fuerza, sustentando la necesidad de control sobre la fuerza en el prensado protésico como método para disminuir fallas en la prótesis 20,[29][30][31][32][33][34][35] y reducir los cambios dimensionales propios del procesamiento del acrílico 36 .…”

“…Las prótesis completas constituyen una estructura artificial con base acrílica y dientes artificiales, alternativa para recuperar las funciones masticatoria, fonética y estética facial 1,2 perdidas 3,4,6 exigiendo considerar en su construcción variaciones anatómicas [31][32][33] e inclusive psicológicas del paciente 28,29 . La colocación de los dientes artificiales constituye un paso fundamental 30 cuyas modificaciones se encuentran asociadas al desplazamiento de sus bases protésicas 6 , composición del acrílico y de procesamiento 12,18,25 que se traducen en alteraciones oclusales 28 evidenciadas en aumento de la dimensión vertical 34 .…”

Accuracy of Digitally Fabricated Wax Denture Bases and Conventional Completed Complete Dentures

“…Six years later, an in vitro study was conducted to assess the influence of different palatal forms (shallow and the deep) on the displacement of the denture teeth during the processing of complete dentures [ 10 ]. To this end, 10 maxillary casts were fabricated by means of duplication for each palatal form.…”

“…The distances between the apices of the metallic pins and the fitted reference points were measured in buccopalatal axes at 3 stages (wax-up, deflasking and after finishing). During all processing stages, and for both palatal forms, the results showed statistically significant movements of teeth [ 10 ].…”