Many patients and friends have this question, which retainer is the best? can avoid recurrence to the greatest extent possible? At the same time, it is possible to combine aesthetics and comfort. First of all, how I designed it: 1. Before the removal of the brackets, the mandibular adhesive bonded retainer (bonded retainer) is worn for life. 2. On the day the brackets are removed, the upper and lower pressure pattern retainer (Vacuum-formed retainer, VFR) is made and worn all day for 6 months.3 After 6 months, the retainer is replaced with an upper and lower Hawley type retainer and worn at night. Adolescents are encouraged to wear them until the age of 18, and adult patients are encouraged to wear them for life. This is my own design, and it took me many years of thinking and learning and figuring out before I settled on a plan. I will leave it to the end to explain why I designed it this way. Every doctor’s perception and experience is different, and individuals have their own personal understanding. Not only Chinese doctors have not reached a consensus, but also doctors in Western countries do not have a unified design, and the literature also says that each has its own advantages. But objectively there is always a conclusion, right? This has to be achieved with an evidence-based medicine approach. At the World Orthodontic Congress WFO in Sydney, I had the opportunity to listen to a talk by Simon Littlewood, a British academic, about this. This is his brief introduction and the title of his talk: Orthodontic Maintenance, How Do We Do It? The following is part of his content, I explain one by one as a popular science. These three are our Hawley, bonded, and compression mold retainers The articles in the literature are actually divided into three, six, and nine levels. From bottom to top the persuasive power (strength of argument) gradually increases, respectively, personal experience, case reports, uncontrolled trials, retrospective studies, controlled trials, randomized controlled studies, and multicenter (systematic) randomized controlled studies. Why is it better to say Randomised Controlled Trials (RCTs) than Retrospective trials (RCTs)? For example, let’s say there are two methods for studying the relationship between smoking and lung cancer. Method A is to survey 50 lung cancer patients, 50 healthy people, ask which of you smokes, and then see which group has a higher percentage of people who smoke. This reflects an indirect relationship. Method B is to survey 50 smokers and 50 nonsmokers and follow them for 30 years to see which group has the higher prevalence of lung cancer. This reflects a more direct relationship and is more convincing. Method A is a Retrospective trial; Method B is a Randomised Controlled Trials study. The authors used an evidence-based medical approach, a multicenter (systematic) randomized controlled study, with the highest strength of argument, which was synthesized by drawing primarily on the studies of these five scholars. So what are the results? The study process is complex, but the conclusion is simple: compression mold retainers win in all three areas: satisfaction, cost, and stability. Conclusion 2: The compression mold and Hawley retainer can be worn part of the time, and the compression mold is better than the Hawley style. The conclusion seems clear, but it is not clear. So look at how another master designed it? The famous Tom Pitts, the chief speaker of Ormco, who has been responsible for many Miss World Beauty Pageant teeth. He has a lot of clinical experience. I will tell his story later. His own orthodontic strategy: 1. mandibular bonded, worn for life; 2. maxillary bonded, worn for 3 years; 3. upper and lower compression model, worn all day for 4 weeks, then at night.