Design: This was a single centre randomized controlled clinical study.

Setting: Department of Child Dental Health, Bristol Dental Hospital, Bristol, UK.

Materials and methods: Thirty-three consecutive patients undergoing fixed orthodontic appliance therapy were included in this study. Using a split-mouth design, diagonally opposite quadrants were randomly allocated a primer, either Orthosolo universal bond enhancer (Ormco, Orange, CA, USA) or Transbond XT primer (3M Unitek, Monrovia, CA, USA). A total of 555 teeth were bonded using a conventional acid-etch technique. 277 received Orthosolo as their primer and 278 received the Transbond XT primer. Bond failures and their positions were recorded at six months.

Results: There was an overall bond failure rate of 1.26%. Four brackets failed in the Orthosolo group (0.72%) and three failed in the Transbond XT group (0.54%).

Conclusion: There was no clinical or statistically significant difference in the in vivo bond failure rates between orthodontic brackets bonded using either Orthosolo universal bond enhancer or the conventional Transbond XT primer.

Design: Epidemiological survey.

Setting: South-western part of Germany (Rhein-Neckar-Kreis); elementary schools in a region with a low orthodontic care rate.

Sample and methods: 494 nine-year-old German schoolchildren (237 males, 257 females, median age 9 years) were examined orthodontically in cooperation with the local community dentistry service. A special measurement ruler was developed to enhance validity and reliability of space measurements on location in the schools.

Results and conclusions: Concerning space conditions in the incisor segments: in the maxilla the variety encountered comprised both space excess and moderate to severe crowding. This was considerably larger in the maxilla than in the mandible. Severe crowding (>5 mm) was found more often in the maxilla than in the mandible and affected around 2–3% of the maxillary dentitions. Also severe contact point displacements (IOTN Grade 4) were mainly restricted to the maxilla (prevalence approximately 3%).

In the canine–premolar segments, the arch segments in males were in general around 0.5 mm larger than among the females, also within each dental stage. In general, the maxilla was more often affected by posterior crowding than the mandible. Anterior crowding seemed to be more prevalent than posterior crowding. With respect to the screening methods used in the present study, reliable and valid measurements were also found to be possible in schools. This may open up further opportunities for orthodontic screening by community dentistry services or similar organizations.

Design: Prospective controlled clinical trial.

Methods: Brackets were bonded to 60 successive patients who were treated at an orthodontic practice in Amman, Jordan. Using a crossover system of allocation, quadrants were bonded using either sandblasted or non-sandblasted brackets respectively. Rely-A-Bond adhesive was used throughout. Bond failures were monitored over one year.

Results: 1112 brackets were assessed. The overall failure rate was 4.0% and the failure rates for non-sandblasted and sandblasted brackets were 4.7 and 3.4% respectively. The odds ratio for at least one bracket failure within the control quadrant compared with the experimental quadrant was 0.50 (95% CI 0.185 to 1.238), which was not statistically significant.

Conclusion: Sandblasting did not significantly improve the retention of mesh based orthodontic brackets in this study.