Table 1 Summary of studies included in the review

1- Hagge et al. [43]

1999

• Prime & Bond (Dentsply/Caulk, Milford, Delaware, USA)

• All-Bond 2 (Bisco Inc, Shaumburg, Ill, USA)

• Scotchbond Multi-Purpose (3M Dental Products Division, St. Paul, MN, USA)

• To investigate the shear bond strength of different adhesive systems applied at refrigerated and room temperatures.

• Refrigeration had no significant effect on the shear bond strength of Prime & Bond or All-Bond 2.

• Shear bond strength of Scotchbond Multi-Purpose was higher at refrigerated temperature than at room temperature.

2- Spohr et al. [33]

2001

• Scotchbond Multi-Purpose (3M Dental Products Division, St. Paul, MN, USA)

• Single Bond 3M Dental Products Division, St. Paul, MN, USA)

• Prime & Bond NT (Dentsply/Caulk, York, PA, USA)

• To investigate the tensile bond strengths of three etch-and-rinse adhesive systems applied to dentin at refrigerated and room temperatures.

• The tensile bond strengths were statistically similar when all adhesive systems were applied at refrigerated and room temperatures

• No adverse effects upon tensile bond strength were observed when adhesive systems were taken directly from refrigerated storage.

3- Borges et al. [25]

2006

• AdheSE (Ivoclar Vivadent, Shaan, Liechtenstein)

• Clearfil SE Bond (Kuraray Corp.,Tokyo, Japan)

• One-Up Bond F (Tokuyama Corp.,Tokyo, Japan)

• To investigate the tensile bond strength to dentin of three self-etching adhesive systems at refrigerated and room temperatures.

• No statistically significant differences in tensile bond strength were found between the adhesive systems applied at refrigerated and room temperatures.

• No adverse effects on tensile bond strength were observed when self-etching adhesive systems were used after being taken directly from the refrigerated storage.

4- Sundfeld et al. [39]

2006

• Adper Prompt L-Pop (3M ESPE Dental Products, St Paul, MN, USA)

• To investigate the penetration of an aggressive self-etching adhesive system at refrigerated and room temperatures into ground and unground enamel surfaces.

• The self-etch adhesive exhibited significantly lower enamel penetration at 6 °C compared to room temperature (25 °C) and to 30 min after removal from the refrigerator.

5- Sadr et al. [1]

2007

• Clearfil Tri-S (Kuraray Medical, Osaka, Japan)

• Clearfil SE Bond (Kuraray Medical, Osaka, Japan)

• To evaluate the micro-shear bond strength to enamel and dentine, pH and hardness of two-self etching adhesives over a period of 60 weeks at 4, 23 or 37 °C.

• No significant difference in the microshear bond strength was observed for either adhesive when stored at room or refrigerated temperatures.

• To assure an optimum performance, it is advisable that the clinicians store these materials in the refrigerator, as the manufacturer instructs, particularly in the warmer areas or seasons.

6- de Alexandre et al. [22]

2008

• Prime&Bond NT (Dentsply Caulk, Milford, DE, USA)

• Adper Prompt L-Pop (3M ESPE Dental Products, St Paul, MN, USA)

• Clearfil SE Bond (Kuraray Medical Inc, Kurashiki, Japan).

• To evaluate the microtensile bond strength, micromorphology of resin-enamel interface and etching patterns promoted by an etch-and-rinse adhesive, and two self-etching adhesives, to ground bovine enamel surfaces, when applied at temperatures of 5 °C, 40 °C, and 20 °C.

• The cold temperature of the tested adhesives did not present a significant reduction in the microtesnile bond compared to room and high temperatures.

7- Donmez et al. [16]

2009

• Clearfil SE Bond (Kuraray Medical Inc., Tokyo, Japan)

• To evaluate the effect of storage temperature on microtensile bond strength of a self-etching primer system to pulp chamber dentin.

• Keeping the adhesive system in refrigerator or room temperature did not affect microtensile bond strength compared to the control group (immediately-delivered from the manufacturer).

• SE Bond adhesive system should be kept in refrigerator until expiry date.

8- Reis et al. [23]

2009

• Adper Single Bond 2 (3M ESPE, St Paul, MN, USA)

• Prime& Bond 2.1 (Dentsply De Trey, Konstanz, Germany)

• To test the effect of adhesive temperature on the microtensile bond strength to dentin and silver nitrate uptake of an ethanol/water and an acetone-based etch-and-rinse adhesive system.

• No significant difference in microtensile bond strength was detected for both adhesives at 5 °C and 20 °C.

9- Faria-e-Silva et al. [2]

2010

• Scotchbond Dual-Cure (3M ESPE, St. Paul, MN, USA)

• Clearfil SE Bond (Kuraray, Tokyo, Japan)

• To evaluate the effect of refrigeration at 4 °C and post-refrigeration times (immediate, 5, 10, 15, or 20 min) on the viscosity and conversion kinetics of dental adhesive resins.

• Refrigeration presented a significant time- and material-dependent effect on the viscosity and polymerization kinetics of the dental adhesives.

• Adhesive agents should be removed from the refrigerator at least 20 min before being used.

10- Graham & Vandewalle. [26]

2010

• iBond (Heraeus Kulzer, SouthBend, IN)

• Clearfil SE Bond (Kuraray, NewYork, NY).

• To compare the shear-bond strength of composite resin to dentin using two different self-etching adhesives after extended storage at room or refrigerated temperatures.

• Refrigerated or room-temperature storage of the one- or two-step adhesive bonding agent did not affect the shear bond strength of composite resin to dentin.

11- Loguercio et al. [24]

2011

• Prime&Bond 2.1 (Dentsply De Trey, Konztanz, Germany)

• Adper Single Bond (3M ESPE, St. Paul, MN, USA)

• To evaluate the effect of adhesive temperature on the resin-dentin bond strength, nanoleakage, adhesive layer thickness, and degree of conversion of ethanol/water- and acetone-based etch-and-rinse adhesive systems.

• No significant difference in terms of microtensile bond strength, degree of conversion, and adhesive layer thickness between the refrigerated temperature (5 °C) and the room temperature (20 °C)

• It does not matter if the refrigerated product is used soon after its removal from the refrigerator or after it reaches room temperature.

12-Sharafeddin et al. [30]

2015

• Adper Single Bond (3M ESPE, St. Paul, MN, USA)

• Clearfil SE Bond (Kuraray Medical Inc., Kurashiki, Japan)

• This study aimed to evaluate the effect of temperature on shear bond strength of etch-and-rinse and self-etching adhesives to ground bovine dentin surfaces, at temperatures of 4 °C, 25 °C and 40 °C.

• Low temperature significantly decreased the shear bond strength of the etch-and-rinse adhesive compared to higher temperatures; therefore, storing this adhesive out of refrigerator could yield better clinical results.

• Refrigeration of the tested self-etch adhesive did not induce a significant difference in the bond strength when compared to other temperatures indicating that the storage temperature before using this adhesive creates no difference.

13- Akarsu & Aktuğ [45]

2020

• Universal Single Bond (3M ESPE, St. Paul, MN,USA)

• All Bond Universal (Bisco Inc, Shaumburg, Ill, USA)

• Clearfil SE Bond (Kuraray Noritake Dental Inc., Osaka, Japan)

• To evaluate the shear bond strength of two universal adhesives and a two-step self-etch adhesive system to dentine at various temperatures (4 °C, 20 °C, 36 °C, 55ºC).

• No statistically significant differences were observed in comparing the shear bond strength of the refrigerated and room-temperature conditions across all tested adhesives.

14- Yumitate et al. [12]

2022

• Tokuyama Universal Bond (Tokuyama Dental, Tokyo, Japan)

• To evaluate the influence of tooth and adhesive temperature during the bonding procedure on the effectiveness of dentin bonding.

• The temperature of the material does not affect bonding effectiveness in terms of microtensile bond strength.

• It does not matter if the refrigerated product is used soon after its taking from the refrigerator or after it reaches room temperature in the clinic.