Effect of Temperature on Surface Hardness of Different Acrylic Materials utilized for space maintainer


  • Amal Abdul Latif Rashid Assist. Prof.Department of Prosthetic Dental Techniques, College of Health and Medical Techniques, Middle Technical University, Baghdad , Iraq
  • Fatima Kadhim Ghadeer Assist. Lecturer.Department of Prosthetic Dental Techniques, College of Health and Medical Techniques, Middle Technical University ,Baghdad , Iraq




acrylic resin materials, hardness, processing temperature


Aim of the study:  surface hardness is essential to avoid the indentation or scratch of space maintainer. Efforts have been made to improve the flexible and cold-cured acrylic's strength, by raising the processing temperature, unless the temperature has a chemical impact on the acrylic's qualities. The aim of this study was to study the effect of elevated temperature on the surface hardness of flexible and cold cured acrylic utilized as space maintainer appliance.

Methods: Sixty specimens were divided into three groups: flexible acrylic ( Lingchen dental) , cold-cured acrylic (vertex) and (Paladur). Each group was subdivided into two subgroups,10 control and10 experimental . The control group for flexible acrylic was injected at 270 °C ,while for the two types of cold -cure, control groups, the specimens were processed at  37°C . The experimental group for flexible acrylic was injected at 290°C and for the two cold -cure types were processed at  70°C. Hardness was tested by Shore A device for  flexible acrylic while for cold -cure specimens, shore D device was used.  


Results : results  showed no significant increase in the hardness of flexible acrylic the mean value of control group is 66.44±0.47 while  for experimental group is   66.50±0.48. For  vertex and Paladur  cold- cured acrylic the surface hardness  was  increased significantly with increasing processing temperature. The mean values of vertex and Paladur  control  groups are around 86.14±0.39 and 88.33±0.39 respectively, while  for experimental groups are   88.39±0.40 and  88.70±0.25

Conclusion : elevated processing  temperature increased the surface  hardness of both types of cold acrylic however; the  hardness of flexible acrylic was  not affected by temperature elevation.


Unal M, Ozkir S, Deste G. Effects of Color and Glitter on the Removable Space Maintainer. Journal of Dental Materials and Techniques. 2020;9(2):76-80.

Beldiman M, Mârţu I, Leiţoiu B, Luchian I, Lupescu O, Bârcă E, editors. Mechanical properties of different types of space maintainers. IOP Conference Series: IOP Conf Ser Mater Sci Eng; 2015.

Sharma A, Shashidhara H. A review: Flexible removable partial dentures. J Dent Med Sci. 2014;13(12):58-62.

Keleştemur O, Yıldız S. Effect of various dual-phase heat treatments on the corrosion behavior of reinforcing steel used in the reinforced concrete structures. Constr Build Mater. 2009;23(1):78-84.

Park SE, Periathamby AR, Loza JC. Effect of surface‐charged poly (methyl methacrylate) on the adhesion of Candida albicans 1. J Prosthodont.2003;12(4):249-54.

Jassim RK, Radhi AA. Evaluation the biological effect of two types of denture base materials reinforced with silanated glass fiber. Journal of baghdad college of dentistry. 2011;23(2).

KJ A. Phillips’ Skinner Science of Dental Materials. St Louis: WB Saunders Company. 1996.

Lee Sy, Lai Yl, Hsu Ts. Influence of polymerization conditions on monomer elution and microhardness of autopolymerized polymethyl methacrylate resin. Eur J Oral Sci. 2002;110(2):179-83.

Vallittu PK, Ruyter IE, Buykuilmaz S. Effect of polymerization temperature and time on the residual monomer content of denture base polymers. Eur J Oral Sci 1998;106(1):588-93.

Phoenix RD, Mansueto MA, Ackerman NA, Jones RE. Evaluation of mechanical and thermal properties of commonly used denture base resins. J Prosthodont. 2004;13(1):17-27.

Craig RG. Powers JM. Restorative dental materials. St Louis: Mosby. 2002.

Keleştemur O, Aksoy M, Yildiz S. Corrosion behavior of tempered dual-phase steel embedded in concrete. Metall Mater Trans A Phys Metall Mater Sci. 2009;16(1):43-50.

Rashid AA-L. Temperature Effect on the Hardness of Different types of Resin Denture Base Materials. Mustansiria Dental Journal. 2013;10(1):69-76.

Al-Neami Z. The effect of different water temperatures during polymerization on some physical and mechanical properties of cold-cure acrylic resin materials. M Tech Thesis, Dental Technologies in the College of Health and Medical Technology. 2005.

Latif Rashid AA. Hardness and Roughness of Flexible Denture Base at Different Injection Time and Different Temperature. Indian J Public Health Res Dev. 2019;10(11).

Rueggeberg F, Craig RG. Correlation of parameters used to estimate monomer conversion in a light-cured composite. J Dent Res 1988;67(6):932-7.

Alraziqi ZNR. Water Temperature Effect on Hardness and Flexural Strength of (PMMA/TiO2 NPs) for Dental Applications. Baghdad Science Journal. 2022:0922-.

ALwash AA, Abdul A. Tikrit Journal for Dental Sciences. 2021.

Çevik P. Evaluation of Shore A hardness of maxillofacial silicones: the effect of dark storage and nanoparticles. Eur Oral Res. 2018;52(2):99-104.

Gautam R, Singh RD, Sharma VP, Siddhartha R, Chand P, Kumar R. Biocompatibility of polymethylmethacrylate resins used in dentistry. J Biomed Mater Res Part B: Applied Biomaterials. 2012;100(5):1444-50.

Lekha K, Savitha N, Roseline M, Nadiger RK. Acetal resin as an esthetic clasp material. Journal of interdisciplinary dentistry. 2012;2(1):11.

Fitton J, Davies E, Howlett J, Pearson G. The physical properties of a polyacetal denture resin. Clinical materials. 1994;17(3):125-9.

Ardelean L, Bortun C, Motoc M. Metal-free removable partial dentures made of a thermoplastic acetal resin and two polyamide resins. Materiale Plastice. 2007;44(4):345-8.

Hargreaves A. The effects of cyclic stress on dental polymethylmethacrylate: I. Thermal and environmental fluctuation. Journal of Oral Rehabilitation. 1983;10(1):75-85.

Seppäläinen AM, Rajaniemi R. Local neurotoxicity of methyl methacrylate among dental technicians. American journal of industrial medicine. 1984;5(6):471-7.

Odian G. Principles of polymerization: John Wiley & Sons; 2004.

Ogawa T, Tanaka M, Koyano K, of Dentistry F. Effect of water temperature during polymerization on strength of autopolymerizing resin. J Prosthet Dent. 2000;84(2):222-4.

Al-Neami Z. The Effect of Different Water Temperatures duringPolymerization on some Physical and Mechanical Properties of Self-Cure Acrylic Resin Material’’. M Tech Thesis, Dental Technologies in the College of Health and Medical Technology. 2005.




How to Cite

Abdul Latif Rashid, A. ., & Kadhim Ghadeer, F. . (2023). Effect of Temperature on Surface Hardness of Different Acrylic Materials utilized for space maintainer. Mustansiria Dental Journal, 19(1), 107–116. https://doi.org/10.32828/mdj.v19i1.996