title: Shear Bond Strength of Intraoral Laser Welding and its Effect on Intrapulpal Temperature Rise in Primary Teeth: An in Vitro Study.
abstract: OBJECTIVE
  This study compared the shear bond strength (SBS) of conventional welding (CW) and intraoral laser welding (LW) on fixed space maintainers (SMs), and investigated the intrapulpal temperature change (ITC) during LW.
  
  
  BACKGROUND
  Lasers have been used for intraoral welding.
  
  
  METHODS
  The SBS test used 26 molar bands divided into two groups, CW and LW. Stainless steel wires were welded to the middle of the buccal and lingual aspects of all the bands, using an Nd:YAG laser for the LW group and silver solder and flux soldering media for the CW group. The samples, fixed to acrylic resin blocks, were subjected to shear testing. In the ITC test, 25 exfoliated primary second molar teeth were used to adapt molar bands. J-type thermocouple wire was positioned in the pulp chamber. ITCs were determined during Nd:YAG laser welding of stainless steel wires to the bands. Mann-Whitney U test was used to determine differences in SBS between the groups. ITCs were analyzed by paired t test.
  
  
  RESULTS
  The SBS between groups showed significant differences (LW: 489.47 ± 135.70; CW: 49.71 ± 17.76; p < 0.001). The mean ITC during LW was 3.64 ± 0.79 (min: 2.4; max: 5.10). None of the samples' ITCs exceeded the critical threshold value (5.5 °C).
  
  
  CONCLUSIONS
  LW obtained a higher-strength joint than CW. ITCs during LW do not present a thermal risk to primary teeth. The intraoral use of LW for SMs in primary teeth is recommended in terms of strength and ITCs.
authors.affiliation: 1 Faculty of Dentistry, Department of Orthodontics, Sifa University , Izmir, Turkey .
authors.forename: Cahide
authors.initials: C
authors.lastname: Aglarci
authors.affiliation: 2 Faculty of Dentistry, Department of Pediatric Dentistry, Akdeniz University , Antalya, Turkey .
authors.forename: Esma
authors.initials: E
authors.lastname: Yildiz
authors.affiliation: 3 Faculty of Dentistry, Department of Orthodontics, Gaziantep University , Gaziantep, Turkey .
authors.forename: Eren
authors.initials: E
authors.lastname: Isman
authors.affiliation: 4 Faculty of Dentistry, Department of Pediatric Dentistry, Gaziantep University , Gaziantep, Turkey .
authors.forename: Mine
authors.initials: M
authors.lastname: Kazak
mesh_terms: D001831:Body Temperature; D001840:Dental Bonding / Q000379:methods*; D003782:Dental Pulp / Q000528:radiation effects*; D006801:Humans; D066298:In Vitro Techniques; D053685:Laser Therapy; D009967:Orthodontic Appliances; D033081:Shear Strength; D014094:Tooth, Deciduous / Q000528:radiation effects* / Q000601:surgery*; D014896:Welding / Q000379:methods*