No abstract

No abstract

Aim: The purpose of this study was to examine the strength of the bonding between orthodontic brackets and different orthodontic adhesives. Materials and methods: To achieve this, the researchers selected 120 extracted premolars and divided them into four groups randomly. Then, one of the three adhesives, Transbond XT, Bracepaste, or Heliosit, was used to join the brackets together. After bonding, the force needed to remove the brackets was tested, and the amount of adhesive that remained on the tooth surface was also noted (referred to as the adhesive remnant index or ARI). Results: The results showed that Transbond XT had an average bond strength of 18.05 ± 5.6 MPa, Bracepaste had an average bond strength of 16.6 ± 5.1 MPa, and Heliosit had an average bond strength of 16.2 ± 4 MPa. The average bond strength and ARI scores for Transbond XT and Bracepaste were similar at 11.10 MPa. The study found that the light-cured composite adhesives provided the strongest bond and left the tooth surface smoother and cleaner. Conclusion: In conclusion, the study presented significant information about the impact on the enamel surface as well as the strength of the bond between orthodontic brackets and different adhesives.

No abstract

Let G ¼ (V,E) be a graph without isolated vertices. A subset D of vertices of G is called a total dominating set of G if for every u 2 V, there exists a vertex v 2 D such that uv 2 E: A total dominating set D of a graph G is called a secure total dominating set of G if for every u 2 VnD, there exists a vertex v 2 D such that uv 2 E and ðDnfvgÞ [ fug is a total dominating set of G. The secure total domination number of G, denoted by c st ðGÞ, is the minimum cardinality of a secure total dominating set of G. Given a graph G, the secure total domination problem is to find a secure total dominating set of G with minimum cardinality. In this paper, we first show that the secure total domination problem is linear time solvable on graphs of bounded clique-width. We then propose linear time algorithms for computing the secure total domination number of chain graphs and cographs.