The paradox of 1-phase vs 2-phase orthodontic treatment.

Abstract

Phase 1 and phase 2 orthodontic treatment may be framed as early vs late orthodontic treatment and the methodology chosen based on the goals of treatment. The quandary may be further considered with an awareness of the present-day accepted delivery systems of orthodontic care: growth modification, camouflage orthodontics, or orthognathic surgery. As promulgated by the orthodontic specialty, 7 of 10 children will have developed a malocclusion by the time they reach peak puberty, and 90% of these malocclusions are dentoalveolar-related, caused by environmental issues (eg, oral habits and medical induced mouth breathing). The remaining 10% of developing pediatric malocclusions are skeletal-based, caused by heredity and chronic neuromuscular problems. These conditions can affect normal jaw growth and development in the transverse, sagittal, and vertical planes of craniofacial growth. It is the objective of first phase, early treatment orthodontics to intercept and rectify abnormal growth patterns of the craniofacial structures, which gave rise to the popularity of functional appliances and other strategies and protocols of early treatment.1McNamara Jr., J.A. Brudon W.L. Orthodontics and dentofacial orthopedics. Needham Press, Ann Arbor, Mich2001Google Scholar In his June editorial, the editor raised the concern of ethics related to phase 1 and phase 2 treatments.2Behrents R.G. One phase or two, and Buridan's paradox.Am J Orthod Dentofacial Orthop. 2016; 149: 775-776Abstract Full Text Full Text PDF Scopus (4) Google Scholar The ethical dilemma in my opinion is whether the clinician should settle for growth modification or camouflage treatment in the treatment of malocclusion.3Carapezza L.J. Objectifying treatment of malocclusion.J Pedod. 1990; 15: 5-12Google Scholar Tulloch et al4Tulloch J.F. Phillips C. Proffit W.R. Benefit of early Class II treatment: progress report of a two-phase randomized clinical trial.Am J Orthod Dentofacial Orthop. 1998; 113: 62-72Abstract Full Text Full Text PDF PubMed Scopus (188) Google Scholar claimed that late Class II camouflage treatment is the gold standard supported by the results of randomized clinical trials. These trials have been seen by many to be based on research with a flawed sample.5Keski-Nisula K. Lehto R. Lusa V. Keski-Nisula L. Varrela J. Occurrence of malocclusion and need of orthodontic treatment in early mixed dentiton.Am J Orthod Dentofacial Orthop. 2003; 124: 631-638Abstract Full Text Full Text PDF PubMed Scopus (91) Google Scholar A quantified goal of many, and a unique benefit of early treatment, is the attainment of proper overbite and overjet relationships (interincisal angle), allowing for unlocking the occlusion and a normal growth direction of the mandible. Growth studies have shown that a proper interincisal angle enhances favorable forward growth rotation of the mandible, allowing a treatment result of not only a Class I dental relationship,6Buschang P.H. Jacob H.B. Mandibular rotation revisited: what makes it so important?.Semin Orthod. 2014; 20: 299-315Abstract Full Text Full Text PDF Scopus (18) Google Scholar but also a Class I skeletal relationship potentially eliminating the need for conventional Class II camouflage distalization mechanics.7Gianelly A.A. A strategy for non-extraction Class II treatment.Semin Orthod. 1988; 4: 26-32Abstract Full Text PDF Scopus (12) Google Scholar Even an “ass” with this universally accepted supportive research would be able to make a proper decision related to the specificity of the timing and methodology of the Class II problem in a developing malocclusion. Author's responseAmerican Journal of Orthodontics and Dentofacial OrthopedicsVol. 151Issue 1PreviewWhen the editorial entitled “One phase or two, and Buridan's paradox” was written, it was intended to point out that there was good evidence to support early treatment performed to reduce protruding incisors.1 The editorial also pointed out that evidence supporting early treatment for Class II malocclusion was lacking, and as a result claims made contrary to the evidence might not always be properly motivated. Because of the latter discussion, it was anticipated that opposing viewpoints would be generated; thus, the response from a knowledgeable, experienced person such as Dr Leonard J. Full-Text PDF