Method: The materials investigated were Alginplus Tropical “A”; Alginmax “B”; Alginmajor “C”; Alginkid Orthodontic “D” and Alginplus Fast “E”(Major Dental, Moncalieri-To, Italy, ww.majordental.com). Fifty dental students were recruited from the University. Two operators, one orthodontist was assigned to mixing and the second assigned to setting. Each subject had two impressions, giving a total of 100 impressions (20 impressions for each alginate). The manufacturer's instruction were followed and impressions taken at 23°C whilst the models were poured with water at 4°C. Each alginate was evaluated by five features: Mixing; Water absorption; Consistency; Processing time; Curing time at final evaluation. For each feature we considered two degrees of quality: POSITIVE, favourable for working time; NEGATIVE, not favourable for working time.
Results: the comparison showed no significant clinical differences between the alginates. Mixing: positive; Water absorption: positive; Consistency: positive; Processing time: positive; Curing time: positive, the best for alginate “D” (1'50'').Total final evaluation: positive.
Conclusion: the differences between the materials were not significant.