Published on March 10, 2014
A Very Good Afternoon 1 phase versus 2 phase
Under the guidance of : Dr. Mohammad Mushtaq, PROFFESSOR & HOD By: Sneh Kalgotra, 2nd Year P.G. Department of Orthodontics & Dentofacial Orthopaedics, GDC&H, Srinagar.dital jet versus pendulum appliance
One-phase vs 2-phase treatment for developing Class III malocclusion: A comparison of identical Twins. Junji Sugawara, Zaher Aymach, Hiromichi Hin, Ravindra Nanda. 1 phase versus 2 phase
About the authors 1 phase versus 2 phase Ravindra Nanda (born 19 February 1943) is the professor and Head of CraniofacialDepartment and Chair of the Division of Orthodontics at the University of Connecticut School of Dental Medicine. He is an innovator of various appliances in orthodontics. With 10 books and 105 artcles to his credit Ravindra Nanda Dr. Nanda receiving Life membership of
About the authors Private practice, Nagoya, Japan. Has 9 publications to his credit. 1 phase versus 2 phase Junji Sugawara Zaher Aymach Lecturer and assistant researcher, Division of Maxillofacial Surgery, Tohoku .University, Sendai, Japan. Has 63 publications to his credit.
prolouge • In the treatment of skeletal Class III growing patients, it has become a common practice to intervene early with orthodontic or orthopedic treatment modalities as a part of a 2-phase treatment approach. • Although orthopedic forces that attempt to control or alter the skeletal framework in skeletal Class III patients appear to be remarkably effective in the initial stages, the results are rarely maintained in the long term. 1 phase versus 2 phase
Therefore, the key question is “what differences in jaw growth or treatment modality and outcome will there be between patients who undergo 1-phase treatment and those who don’t?” 1 phase versus 2 phase
Critical appraisal of title • One-phase vs 2-phase treatment for developing Class III malocclusion: A comparison of identical twins. Title reflects the aim of the study. Variables are not clearly mentioned in the title. The type of study is not mentioned in the title. It comprises of 16words- appropriate. It is not specific. Title is incomplete as it suggest nothing about the parameters being undertaken in the study.1 phase versus 2 phase
Proposed alternative title One-phase vs 2-phase treatment for mild to moderate developing Class III malocclusion: A comparison of identical twins- A case report. - 19 words. 1 phase versus 2 phase
Critical appraisal of the abstract Its informative and comprehensive in its contents. Gives brief overview of the whole study. Key words are NOT clearly mentioned. 1 phase versus 2 phase
CRITICAL APPRAISAL OF INTRODUCTION Introduction is meaningful. Introduction is SHORT. It is built on the existing literature. Citations that are reported, are relevant and pertinent to the study and followed with correct references in the list. Purpose of the study is clearly mentioned in the introduction. 1 phase versus 2 phase
Material and methods The patients, monozygotic twin sisters (Fig 2), were referred to our department at Tohoku University, Sendai, Japan, in 1996 when they were 9 years old for orthodontic treatment of anterior crossbites. 1 phase versus 2 phase Fig 2
Material and methods Both twins had almost the same orthodontic problems that included a prognathic profile, mild mandibular asymmetry, Class III denture bases, deviation of mandibular midlines, and occlusal interference of the incisors (Fig 3). 1 phase versus 2 phase Fig 3
Material and methods Cephalometrically, their skeletofacial types were classified as Class III short-face types. The short- face tendency was more pronounced in Patient 2 (Fig 4). 1 phase versus 2 phase Fig – 4
1 phase versus 2 phase
Material and methods Treatment objectives for Patient 1 were established with the 2-phase treatment approach, whereas Patient 2 was managed with a 1-phase treatment concept. The treatment objectives for Patient 1 were (1) Phase 1 treatment involving dental correction of the anterior crossbite, (2) growth monitoring and oral health care until the postadolescent period, (3) fixed appliance treatment for correction of the remaining orthodontic problems, and (4) retention and long-term follow-up.1 phase versus 2 phase
Material and methods For Patient 2, the treatment objectives were (1) growth monitoring and oral health care until the post adolescent period, (2) correction of the malocclusion with fixed appliance treatment together with skeletal anchorage that would allow us to circumvent the need for mandibular premolar extraction, and (3) retention and long-term follow-up. 1 phase versus 2 phase
Treatment progressIn Patient 1, the first phase of treatment began with facemask therapy and 2 x 4 appliances. The aim was to correct her anterior crossbite dentally. The crossbite and maxillary dental midline shift were corrected in 6 months. 1 phase versus 2 phase
At the age of 10 and after the first phase of treatment, Patient 1's prognathic profile and dental malocclusion had improved significantly. At the same time, growth observation in Patient 2 showed that all her orthodontic problems were exactly as they had been at the initial examination.1 phase versus 2 phase
Before the second phase of treatment, • Patient 1 still had a prognathic profile, with some minor dental problems, particularly in the mandibular dentition. She had a lateral crossbite on the right side, a mild Class III denture base, and mild mandibular incisor crowding. At the same stage, • Patient 2 demonstrated more severe orthodontic problems than her sister did at this age. She had a skeletal Class III malocclusion with a short-face tendency, premature contact at the incisors, a dental midline shift, an anterior crossbite, severe crowding of the maxillary anterior teeth, and retroclined mandibular incisors. 1 phase versus 2 phase
1 phase versus 2 phase Patient 1's orthodontic problems, preadjusted fixed appliance treatment was started, and short Class III elastics were used to improve the Class III denture bases and prevent proclination of the mandibular incisors during leveling and aligning.
Treatment for Patient 2 started with bonding brackets on the mandibular teeth and placing resin caps on the maxillary molars to open the bite for maxillary bonding. Open-coil springs were used to make space and procline the maxillary incisors. Simultaneously, distalization of the mandibular posterior teeth was started with the skeletal anchorage system, which uses an orthodontic miniplate as a temporary anchorage device 1 phase versus 2 phase
After 12 months of active fixed appliance treatment, Patient 1's malocclusion was corrected. She obtained a balanced profile, with adequate overjet and overbite, proper anterior guidance, and rigid posterior intercuspation of the teeth. On the other hand, Patient 2's treatment with the skeletal anchorage system lasted 18 months. She also achieved an acceptable Class I occlusion and a satisfactory profile at debonding. • After 30 months of retention, both twins have maintained a good occlusion except for a minor relapse of the maxillary right first premolar in Patient 2. Overall, satisfactory results were achieved. 1 phase versus 2 phase
1 phase versus 2 phase
1 phase versus 2 phase
COMPARISON OF TREATMENT PROGRESS AND RESULTS IN THE TWINS Comparisons of the twin sisters took place at 4 time intervals 1. The initial examination was at age 9 years. Because they are monozygotic twins, it is no surprise that even their dentitions were almost identical. 1 phase versus 2 phase
2.After Patient 1's first phase of treatment (age, 10 years), the clinical pictures clearly show the efficiency of early intervention for her. Cephalometric superimposition shows significant dentofacial differences between the sisters at this stage. Patient 1's crossbite was corrected by proclinatoin of her maxillary incisors, forward displacement of the maxilla, and clockwise rotation of the mandible. This gave her an orthognathic facial profile compared with Patient 2. 1 phase versus 2 phase
3. Before fixed appliance treatment (age, 16 years), the skeletal differences between them at 10 years gradually disappeared during the pubertal growth spurt, and almost no difference could be observed between their skeletal profiles at 16 years. The only difference perhaps was in the position of the maxillary incisors. The orthodontic effect of the facemask could still be seen on Patient 1's maxillary Incisors. 1 phase versus 2 phase
1 phase versus 2 phase
4. During the retention period (age, 20 years), we superimposed the twins’ final records. Interestingly, although they underwent orthodontic treatment with completely different treatment regimens (1-phase vs 2-phase), their dentofacial morphologies were identical . 1 phase versus 2 phase
Critical appraisal of material and methods The local ethical committee was not consulted. Informed and written consent was obtained before the treatment was started both from the patients and the parents. 1 phase versus 2 phase
Critical appraisal of material and methods It is an experimental study. Pre-test, post- test comparisons are used. Parameters used for maxillary length and mandibular length are not clearly mentioned. since authors believe that phase 1 treatment has any positive effect on psychology of the patient than it is ethically wrong to give benefit of such treatment to one patient only. One advantage of the study is it rules out the bias produced due to genetics. 1 phase versus 2 phase
DISCUSSION • The advantage of using monozygotic twins in such a comparative case report is that all differences in skeletal growth, beyond the error of measurement, can be assumed to be nongenetic and, therefore, the result of the environment. • Recent clinical trials have suggested that in the longterm the improvement in the skeletal malocclusion obtained after a first phase of treatment is not significant when compared with a control group that had no growth modification treatment. 1 phase versus 2 phase
It was obvious that the early correction of the anterior crossbite did not make a positive impact on jaw growth. It seems that morphogenetic factors are still stronger and much more dominant than environmental factors in the matter of jaw growth. Patient 2 who was managed with a 1-phase treatment, had to undergo treatment with the skeletal anchorage system. The skeletal anchorage system is a viable modality for distalizing mandibular molars. 1 phase versus 2 phase
Conclusion 1. In spite of the differences in treatment timing and modalities (1- phase vs 2-phase treatment), both twin sisters achieved almost identical dentofacial results. This implies that early treatment had no impact on jaw growth in the pubertal growth period.1 phase versus 2 phase
Conclusion 2. Although phase 1 treatment had no impact on jaw growth, it made the phase 2 treatment simpler and easier. Therefore, 2-phase treatment might be more suited for mild to moderate Class III patients than 1- phase treatment. 3. The criteria for the selection of 1-phase or 2-phase treatment depend entirely on the patient’s requirements. Because the biologic outcome is the same, the basis for opting for a particular treatment regimen can be complicated. Cultural, environmental, and psychosocial factors need to be considered more carefully. 1 phase versus 2 phase
Review of literature 1 phase versus 2 phase
Outcomes in a 2-phase randomized clinical trial of early class II treatment J.F.Camilla Tulloch, William R Proffit, Ceib Phillips. (AJODO 125, JUNE 2004). The differences created between the treated children and untreated control group by phase 1 treatment before adolescence disappeared when both groups received comprehensive fixed appliance treatment during adolescence. This suggests that 2-phase treatment started before adolescence in the mixed dentition might be no more clinically effective than 1- phase treatment started during adolescence in the early permanent dentition. 1 phase versus 2 phase
Two phase treatment of Class III malocclusion. Siddegowda R, Sahoo KC, Jain S • The earlier the intervention, the greater the chances of positive response, regarding transversal maxillary advancement. 1 phase versus 2 phase
Is early class III protraction facemask treatment effective? A multicentre, randomized, controlled trial: 15‐month follow‐up. JCO 2010. • Early class III orthopaedic treatment, with protraction facemask, in patients under 10 years of age, is skeletally and dentally effective in the short term and does not result in TMJ dysfunction. Seventy per cent of patients had successful treatment, defined as achieving a positive overjet. However, early treatment does not seem to confer a clinically significant psychosocial benefit. 1 phase versus 2 phase
Is early class III protraction facemask treatment effective? A multicentre, randomized, controlled trial: 3-year follow-up JO 2012. • The favourable effect of early class III protraction facemask treatment undertaken in patients under 10 years of age, is maintained at 3-year follow-up in terms of ANB, overjet and % PAR improvement. The direct protraction treatment effect at SNA is still favourable although not statistically significantly better than the CG.1 phase versus 2 phase
Moyers R. Handbook of orthodontics. 4th ed. Chicago: Year Book; 1988. p. 346-7, 433-4. • “there is no assurance that the results of early treatment will be sustained and that 2-phased treatment will always lengthen overall treatment time. Early treatment not only may do some damage or prolong therapy, it may exhaust the child’s spirit of cooperation and compliance.” 1 phase versus 2 phase
Critical reflection 1 phase versus 2 phase
Critical reflection • This article is very relevant for day to day patient care. • Further studies need to be undertaken. • Considerations like environmental factors • And psycho-social factors should be concerned. 1 phase versus 2 phase
References 1. Gebeile-Chauty S, Perret M, Schott AM, Akin JJ. Early treatment of Class III: a long-term cohort study. Orthod Fr 2010;81:245-54. 2. Kanno Z, Kim Y, Soma K. Early correction of a developing skeletal Class III malocclusion. Angle Orthod 2007;77:549-56. 3. Mandall N, DiBiase A, Littlewood S, Nute S, Stivaros N, McDowall R, et al. Is early Class III protraction facemask treatment effective? A multicentre, randomized, controlled trial: 15-month follow-up. J Orthod 2010;37:149-61. 4. Sugawara J, Asano T, Endo N, Mitani H. Long-term effects of chincap therapy on skeletal profile in mandibular prognathism. Am J Orthod Dentofacial Orthop 1990;98:127-33. 5. Mitani H, Sato K, Sugawara J. Growth of mandibular prongathism after pubertal growth peak. Am J Orthod Dentofacial Orthop 1993; 104:330-6. 1 phase versus 2 phase
6. Sugawara J, Asano T. The clinical practice guideline for treatment of developing Class III malocclusion. In: Sugawara J, Asano T, editors. Seeking a consensus for Class III treatment. Osaka, Japan: Tokyo Rinsho Shuppan; 2002. p. 21-30. 7. Sugawara J. Clinical practice guidelines for developing Class III malocclusion. In: Nanda R, editor. Biomechanics and esthetic strategies in clinical orthodontics. St Louis: Elsevier; 2005. p. 211-42. 1 phase versus 2 phase
8. Sugawara J, Mitani H. Facial growth of skeletal Class III malocclusion and the effects, limitations, and long-term dentofacial adaptations to chincap therapy. Semin Orthod 1997;3:244-54. 9. Skieller V, Bj€ork A, Linde-Hansen T. Prediction of mandibular growth rotation evaluated from a longitudinal implant sample. Am J Orthod 1984;86:359-70. 10. Bj€ork A, Skieller V. Normal and abnormal growth of mandible. A longitudinal cephalometric implantation study over a 25-year period. Inf Orthod Kieferorthop 1984;16:55-108. 11. Sugawara J. A bioefficient skeletal anchorage system. In: Nanda R, editor. Biomechanics and esthetic strategies in clinical orthodontics. St Louis: Elsevier; 2005. p. 295-309. 1 phase versus 2 phase
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