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orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy
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orthodontic Dogmas /certified fixed orthodontic courses by Indian dental academy

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The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats.

The Indian Dental Academy is the Leader in continuing dental education , training dentists in all aspects of dentistry and offering a wide range of dental certified courses in different formats.

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  • 1. www.indiandentalacademy.com
  • 2. INDIAN DENTAL ACADEMY Leader in continuing dental education www.indiandentalacademy.com www.indiandentalacademy.com
  • 3. CONTENTS • • • • • • • • • • Introduction Angles philosophy Calvin case philosophy Tweed philosophy Begg philosophy Extraction related dogmas Functional appliance dogmas Retention related dogmas Timing of treatment Conclusion www.indiandentalacademy.com
  • 4. A. INTRODUCTION • DOGMA: • Dogma may be defined as : – System of principles or tenets – or – A doctrine authoritatively laid down – or – A settled opinion, belief or principle. www.indiandentalacademy.com
  • 5. • Orthodontic dogma can be based on : Truth Fiction www.indiandentalacademy.com
  • 6. • Cults and Charismatic leaders have been more instrumental in establishing our value systems than has any demonstrated superiority of one method over another. The focus has been on techniques and their empirical value to practitioners. www.indiandentalacademy.com
  • 7. • The problem lies in many of the dogmatists demanding ALL or NONE acceptance. This type of human nature does not serve to advance knowledge, understanding, or even tolerance for opposing views. Until proven otherwise, it seems that many of our values and hence our decisions are based essentially on dogma. www.indiandentalacademy.com
  • 8. • B. ANGLE’S PHILOSOPHY : (1910’s) • • • • Edward angle struggled with both facial esthetics and stability of result as potential complications in his efforts to achieve an idealized normal occlusion. Angle was influenced by : 1. Philosophy of Rousseau: Rousseau emphasized the perfectability of man. His strong belief that many of the ills of modern man could be traced to the harmful influences of civilization impressed Angle. www.indiandentalacademy.com
  • 9. • Wolff’s Law of Bone : • Angle was impressed by the discovery that the architecture of bone responds to the stresses placed on that part of the skeleton. www.indiandentalacademy.com
  • 10. • This led Angle to two key concepts: • a. Skeletal growth could be influenced by external pressures: • Use of elastics • Use of extraoral force • b. Second Concept was that proper function of dentition would be the key to maintaining teeth in their correct position. www.indiandentalacademy.com
  • 11. • He described his edgewise appliance, the first appliance capable of fully controlling root position, as the “BONE GROWING APPLIANCE”. www.indiandentalacademy.com
  • 12. • Therefore, for Angle proper Orthodontic Rx for every patient involved : • • Extraction was not necessary for stability of result or esthetics. • • Expansion of dental arches. Use of Elastics to bring teeth into occlusion. To Angle and his followers, relapse after expansion of the arches or rubber bands to correct overjet and overbite meant only that an adequate OCCLUSION had not been achieved. www.indiandentalacademy.com
  • 13. • Angle’s postulate : • Upper first molars were the KEY to OCCLUSION and that the U & L molars should be related so that mesiobuccal cusp of upper molar occludes in buccal groove of lower molar. • If this molar relationship existed and the teeth were arranged on smoothly curving LINE OF OCCLUSION, then normal occlusion would result. www.indiandentalacademy.com
  • 14. • He believed these teeth were key to occlusion because they : • Are the largest teeth. • Are firmest in their attachment. • Have a key location in dental arches. • Help determine dental and skeletal vertical proportions due to lengths of their crowns. www.indiandentalacademy.com
  • 15. • Occupy normal position in arches far more often than any other teeth because they are first permanent teeth and are less restrained in taking their position. • More or less control positions of other permanent teeth anterior and posterior to them. • Have the consistent timing of eruption of all the permanent teeth. • Determine interarch relationship of all other teeth upon their eruption and “locking with mandibular 1st molars. www.indiandentalacademy.com
  • 16. • Angle believed that facial harmony and balance were only possible with full complement of teeth in “Normal” occlusion. With emphasis an dental occlusion that followed less attention was given on facial esthetics. www.indiandentalacademy.com
  • 17. • C. CALVIN SUVERIL CASE : (1920’s) • Strongly criticized Angle’s non extraction dogma because of its effect on:– Facial esthetics - i.e. excess dental protrusion following extreme expansion. – Stability. • Advocated first premolar extractions for treatment of malocclusions. www.indiandentalacademy.com
  • 18. • D. TWEEDS PHILOSOPHY (1940’S): • Tweed’s dramatic public presentation of consecutively treated cases with premolar extraction caused a revolution in American orthodontic thinking and led to widespread reintroduction of extraction into orthodontic therapy by late 1940’s. • Tweed’s studies indicated that the failure both functionally and facially of the aforementioned non-extraction cases was result of procumbent lower anterior teeth. • Tweed therefore advocated uprighting and even retroclining the lower anterior incisors for greater stability and esthetics. www.indiandentalacademy.com
  • 19. • Tweed summarizes his philosophy on which his appliance therapy is based as follows:– Great majority of malocclusions are characterized by a deficiency between teeth and “basal bone” which shows itself in an abnormally forward relationship of teeth to their respective jaw bases. – Normal occlusion is best maintained with the mandibular incisor teeth in their normal axial inclination when related to Frankfort plane, which is approx. 65° (FMIA). www.indiandentalacademy.com
  • 20. • Ultimate in balance and harmony of facial esthetics is achieved only when the mandibular incisors are positioned over basal bone (the medullary bone of respective basal arches). • Normal relationship of mandibular incisor teeth to their basal bone (basal arch) is most reliable guide in diagnosis and treatment of class I, class II & Bimaxillary protrusion malocclusions, and in attainment of balance and harmony of facial profile and permanence of tooth position. www.indiandentalacademy.com
  • 21. Tweed’s diagnostic facial triangle : • Tweed conceived diagnostic facial triangle as a basis for diagnosis and treatment planning. – Tweed establishes – 25° as a norm for FMA – 90° as a norm for IMPA – 65° as a norm for FMIA. www.indiandentalacademy.com
  • 22. • FMIA FORMULA: – Tweed adopted an FMA range of 16° -35° with an average norm of 25°. – If FMA is 16° - 25° less extraction is necessary than when FMA is >30°. – When FMA is 30° the mandibular incisors must be tipped to 85° to maintain 65° for FMIA. www.indiandentalacademy.com
  • 23. • Successful treatment according to Tweed, requires that the triangle should be attainable. He provides following instructions:– Aim should be to maintain FMIA of 70° - 75° when FMA is 20°. – FMIA angle of 65° when FMA is 30°. – When FMA is below 20°, the aim should be not to exceed an incisor inclination of 92°. www.indiandentalacademy.com
  • 24. • STABLE ANCHORAGE: – It is of fundamental importance in prevention of forward mandibular tooth shifting when intermaxillary force is used and when attempt is made to move mandibular incisor teeth through “basal bone”. – The first and most important step in the treatment of all malocclusion, therefore according to Tweed is Anchorage preparation. www.indiandentalacademy.com
  • 25. E. BEGG’S PHILOSPHY (1940’s): • Independently of Tweed, Begg also abandoned non extraction philosophy due to concerns about relapse rather than profile. • Begg or differential force technique is a unique approach to orthodontic treatment Begg’s philosophy is based on:– Theory of attritional occlusion. – Theory of differential pressures. www.indiandentalacademy.com
  • 26. THEORY OF ATTRITIONAL OCCLUSION: • Dr. Begg has founded his concept of correct occlusion upon his studies of ancient skulls of Australian aboriginals (Stone Age man). • Dr. Begg discarded the concept of “Text book normal” occlusion and adapted stone age man’s attritional occlusion as correct occlusion • Correct occlusion is not fixed or particular anatomic state but a changing functional process undergoing continual modification www.indiandentalacademy.com
  • 27. . • Factors in development of anatomically correct occlusion: – 1. Changing anatomy of teeth which is dependent on tooth attrition. – 2. Tooth movement (migration ): Continued mesial migration and continued vertical eruption both of which compensate for tooth attrition. www.indiandentalacademy.com
  • 28. Characteristics of stone age man dentition: • Due to coarse, fibrous and gritty food their dentitions displayed marked occlusal and interproximal attrition. • In anterior region :- incisors had worn down and were in edge to edge bite. • With the elimination of incisal over bite, mesial migration of mandibular teeth could take place without incurring lower incisor imbrication. • Lower incidence of caries • Total reduction in arch length resulting from attrition amounted approximate to one bicuspid width either side of dental arches by the time the aboriginal was 20 years of age. www.indiandentalacademy.com
  • 29. Civilized man dentition: • In present day and age with refined and precooked food having replaced the former rougher diet there is: – Correspondingly less dental attrition – Increased liability to caries and periodontal disease – Absence of attrition in presence of mesial tooth migration means that dental over crowding where it exists is unrelieved and seen clinically in lower incisor region. – Retention of overbite prevents the escape of lower incisors into edge to edge relationship with the uppers. www.indiandentalacademy.com
  • 30. • Dr. Begg used his findings from his study of Australian aboriginal occlusion as a justification for extraction. • He argues that if this present era tooth material is not lost through attrition, it would be reasonable to cause proportionate reduction artificially e.g.: extraction. www.indiandentalacademy.com
  • 31. THEORY OF DIFFERENTIAL PRESSURE: • • Dr. Begg’s observations were based to a large extent on the work of Storey and Smith and their experiments on tooth movement response to different pressure applications. Light orthodontic forces: – – – – Optimal forces Move teeth rapidly - continuous movement. Cause less discomfort Minimum damage to investing tissues. www.indiandentalacademy.com
  • 32. • Heavy forces cause: – Undermining resorption – Intermittent tooth movement – Patient discomfort and damage to investing tissues. • Differential force technique is designed to permit teeth to move toward their anatomically correct positions in the jaws under the influence of very light forces - as would naturally occur in presence of attrition. www.indiandentalacademy.com
  • 33. • • • Since larger posterior teeth are slowly moving “Downstream” with currents of mesial migration, rapid, distal movement of smaller anterior teeth is possible with application of light forces in presence of round arch wires and brackets that permit distal crown tipping. In Begg technique employment of light intra-oral forces don’t place undue strain on the anchor molars. This, plus the fact that posterior teeth are not moved distally. ↓ Precludes the use of distally directed extraoral forces. www.indiandentalacademy.com
  • 34. F. EXTRACTION RELATED DOGMAS: • They can be classified as : – I. Premolar extraction and TMD. – II. Second molar extraction. www.indiandentalacademy.com
  • 35. • PREMOLAR EXTRACTION AND TEMPOROMANDIBULAR DISORDERS (TMD) : • Vertical dimension collapses • Over-retraction and retroclination of incisors. • • Bring about premature anterior contacts Distally displace the mandible and mandibular condyle. www.indiandentalacademy.com
  • 36. • Witzig and Spahl: • Were critical of premolar extraction, stating that this method of treatment “was a technique that was never designed with face, the stability of occlusion, nor the health of TMJ in mind, merely the decrowding of arches”. www.indiandentalacademy.com
  • 37. • They proposed that premolar extraction led to : • - Reduction in vertical dimension. • • • • - Overretraction of premaxilla. - Retroclination of upper incisors. - Deepening of bite. - Anterior incisal interferences. www.indiandentalacademy.com
  • 38. • This in turn led to : • - Distalization of the mandible. • - Posterior displacement of condyles and TMD. • They recommended that when relief of crowding required extractions, it was not premolars but SECOND MOLARS that should be removed which will result in: • - An increase in vertical dimension. • - A pleasing full face. • - Healthy TMJ. www.indiandentalacademy.com
  • 39. • With time however drawbacks of biscuspid extraction started surfacing up. • They were: • Effects on facial esthetics. • TMJ problem • Effect on 3rd molar eruption. www.indiandentalacademy.com
  • 40. Facial esthetics: • Narrow smile line (less teeth). • Sunken in: appearance due to decreased support to upper lip • “Old age” appearance due to decreased vertical height. • “Fish like” appearance - extraction of bicuspids in class II case and retraction of premaxilla - nose appears longer and prominent www.indiandentalacademy.com
  • 41. TMJ Problem • Dr. H.F. Wilson, while treating TMJ patients observed and concluded that 4- biscuspid extraction cases causes TMJ problems due to retrusion of mandibular arc of closure by:• Mesially tilted posterior teeth. • Distally tilted canine and lower incisors. • Persistent deep overbite. • He also observed that successful treatment to many of his cases involved the reverse tooth movement to what was performed in the original orthodontic treatment. www.indiandentalacademy.com
  • 42. Third molars • Extraction of bicuspids did not help eruption of impacted 3rd molars, as most of the space would be used for relief of crowding. The result is loss of 8 teeth. www.indiandentalacademy.com
  • 43. PROPOSAL OF SECOND MOLAR EXTRACTION: • As an alternative Dr. Wilson proposed 2nd molar extraction and is regarded as “Father of 2nd molar extraction concept”. www.indiandentalacademy.com
  • 44. Reasons Given : – Prevents the retraction of maxillary anteriors as there are no bicuspid spaces to close. This allows mandible to grow downward and forward which is compatible with TMJ. – Faces are fuller and smile lines are broader. – Increased stability as the gigantic forward thrust of 2nd molar is replaced by 3rd molars. – Treatment easier. – Treatment time is shorter. – Avoidance of elastics and use of headgears and prolonged use of fixed appliance or retainers. – Leaves the patient with 28 intact teeth. www.indiandentalacademy.com
  • 45. • Finally, Witzik and Spahl comments that, “To avoid dished - in faces, flattened smiles, unstable occlusion and compromised TMJ for the patients, needing orthodontic treatment accompanied by dental extractions there is no alternative to 2nd molar extraction; there is no debate”. www.indiandentalacademy.com
  • 46. G. FUNCTIONAL APPLIANCE DOGMAS: • I. Roux (1883): • Influence of natural forces and functional stimulation on form were first reported by Roux in 1883 as a result of studies he performed on tail of dolphins. • He described the characteristics of functional stimuli as they build, mold, remold and preserve tissue. • His working hypothesis i.e Shaking the bonding substance of bone became the background of both general orthopaedic and dentofacial orthopaedic procedures. www.indiandentalacademy.com
  • 47. • II. Kingsley (1880) : • • Introduced the term and concept of “Jumping the Bite” for patients with mandibular retrusion. He inserted a vulcanite palatal plate consisting of an anterior incline that guided the mandible to a forward position when patient closed on it. This maneuver corrected the sagittal relationship without tipping the lower incisors forward. www.indiandentalacademy.com
  • 48. • III. Pierre Robin: • • The classic MONOBLOC was used by Pierre Robin at beginning of twentieth century to treat glossoptotic mandibular retrognathic syndrome. He belived that passive repositioning of an underdeveloped structure would make it conform to the normal and that “CATCH UP” growth would occur. www.indiandentalacademy.com
  • 49. • IV. Andresen (1908) : • “Activator” was originally used by Andresen with vertical extensions to contact the contiguous lingual surfaces of mandibular teeth. • Andresen inspiration for the design of his appliance came from “Bite jumping appliances” of Norman Kingsley. Andresen thought that this retention appliance was effective in stimulating jaw development. • Andresen modified the Kingsley vulcanite eruption control appliances to “ACTIVATE” the musculature to create a favorable environment for functionally induced mandibular change. www.indiandentalacademy.com
  • 50. • HYPOTHESIS : Andresen’s working hypothesis was that protractor muscles of the mandible could be stimulated or “Activated” to assist in achieving a dental sagittal correction. • He envisioned that the stretched muscles just beyond resting length produced an isotonic contractile force which in turn is transmitted and distributed to selected teeth in contact with the appliance. www.indiandentalacademy.com
  • 51. • Andresen made no claim that his “Norwegian system” was better than other techniques, but he did believe that it was superior to other orthodontic approaches given the geographic problems, dental manpower situation and need for caries prevention. www.indiandentalacademy.com
  • 52. • After 25 years of using his mode of orthodontic therapy, Andresen published following summary : – Basis for Norwegian system is neither a single “natural ideal norm concept” nor a “biometric mean”. Individual variation is normal for civilized persons. Norwegian system is not bound to the usual orthodontic goal of normal occlusion coincident with eruption of second molar teeth. – Norwegian system has introduced the “prolonged prognosis” of the topographic relationship as well as eruption of 3rd molars, defining the goal as “The functional and cosmetic optimum” serving as supportive periodontal therapy for patient in later life. www.indiandentalacademy.com
  • 53. • Appliances used in Norwegian system can be best termed “Muscle and Circulation activators”, since they are based on a reciprocal and mutual effect between the gnathophysiognomic complex, the circulatory system and the appliance itself. The activators activate the appropriate muscles while the muscles in turn, activate the appliances. www.indiandentalacademy.com
  • 54. V. Karl Haupl (1934) : • Haupl a Periodontist and histologist was impressed with results obtained by Andresen’s functioning retainer. • Haupl became convinced the appliance induced growth changes in physiologic manner and stimulated or transformed the natural forces with an intermittent functional action transmitted to jaw, teeth and investing tissues. • Familiar with the work of William Roux who gave “shaking theory”, Haupl believed that this was a clinical validation of the concept. www.indiandentalacademy.com
  • 55. According to Haupl : • Goal of functional appliance is to use functional stimulus, channeling it to greatest extent the tissues, jaws, condyles and teeth allow. The mode of channeling is passive in the sense mechanical – force producing elements are unnecessary. • The forces that arise are purely functional and intermittent. This is the only mode of force application that can build up tissue because bone remodeling cannot take place in presence of continuous active forces. • Haupl stated that the only true physiologic tooth movement takes place under purely muscular influences. On this point he tolerated no contradiction. www.indiandentalacademy.com
  • 56. • Principles of Haupl and their applications to activator therapy had some detrimental consequences for development of orthodontics in Europe: – Many orthodontists were convinced that only tissue – preserving treatments such as that provided by the activator should be used. The application of mechanical force was considered unbiologic and technical error. – Convictions of European orthodontists were upheld by research of Oppenheim who published his investigations under title ‘Crisis in Orthodontics (1933). www.indiandentalacademy.com
  • 57. • He noted the potential tissue damaging side effects of heavy orthodontic forces. This strengthened working hypothesis of Haupl, who decried the use of artificial, mechanically produced forces on oral tissues • For many schools throughout Europe the activator became the one universal appliance. Too often, however its widespread use occurred in absence of differential diagnosis and correct application. • Some European Orthodontists even considered active removable appliances with screws and springs dangerous to the teeth and investing tissues. www.indiandentalacademy.com
  • 58. VI. Frankel and Frankel (1989): • They make a sharp contrast between the FR and other so called “Functional appliances” as the activator and bionator. The activator or bionator, although thought to transmit “functional stimuli”, constitutes a foreign body in oral cavity. www.indiandentalacademy.com
  • 59. • According to Frankel: – Forces generated by muscles of cheek, lip and tongue can only have the quality of “functional stimuli” if they are in natural and direct contact with adjacent dentoalveolar structures and palate. – Pressure exerted by any appliance, even produced by muscular forces is and remains an application of pressure and has nothing to do with a “functional stimulus”. www.indiandentalacademy.com
  • 60. • In terms of orthodontic effect, there is in principle, no difference whether forces press the appliances against the teeth and the supporting tissue as a result of stretching of muscular tissues OR as a result of stretch – reflex contractions of the related muscles. www.indiandentalacademy.com
  • 61. H. RETENTION • Working Definition of Retention : • The holding of teeth in ideal esthetic and functional positions. • Much has been written and stated concerning the retention of corrected malocclusions of the teeth. www.indiandentalacademy.com
  • 62. • Different philosophies or schools of thought have developed and our present day concept generally combine several of these theories : • I. SCHOOLS OF RETENTION: • 1. OCCLUSION SCHOOL: Kingsley stated, “The occlusion of the teeth is the most potent factor in determining the stability in a new position”. • Many early writers considered that proper occlusion was of prime importance in retention. • www.indiandentalacademy.com
  • 63. 2. APICAL BASE SCHOOL – In middle 1920s a second school of thought formed around writings of Axel Lundstrom. – He suggested that the apical base was one of the most important factors in correction of malocclusion and maintenance of a correct occlusion. – McCauley suggested that intercanine width and intermolar width should be maintained as originally presented to minimize retention problems. www.indiandentalacademy.com
  • 64. • 3. MANDIBULAR INCISOR SCHOOL: • Grieve and Tweed suggested that the mandibular incisors must be kept upright and over basal bone. www.indiandentalacademy.com
  • 65. • • 4. MUSCULATURE SCHOOL: Rogers introduced a consideration of the necessity of establishing proper functional muscle balance. This type of thinking has been followed by Dewey, McCoy and by Allan Broodie. www.indiandentalacademy.com
  • 66. II. THIRD MOLARS AND LATE CROWDING OF MANDIBULAR INCISORS • The role that mandibular 3rd molars play in lower anterior crowding has provoked much speculation in dental literature. • In 1859, Robinson wrote “The dens sapientiae is frequently the immediate cause of irregularity of the teeth”. www.indiandentalacademy.com
  • 67. • Laskin (1971) in a survey of more than 600 orthodontists & 700 oral surgeons found that 65% were of opinion that third molars sometimes produce crowding of mandibulars anterior teeth. www.indiandentalacademy.com
  • 68. • Differing views ranged between extremes and can be expressed as:– Third molars should be removed even on prophylactic basis because they are frequently associated with future orthodontic and periodontal complications as well as other pathologic conditions. – There is no scientific evidence of cause and effect relationship between presence of third molars and orthodontic and periodontal problems. www.indiandentalacademy.com
  • 69. STUDIES RELATING THIRD MOLARS TO CROWDING OF THE DENTITION: - • Bergstrom and Jensen (1961):– Study design – Cross sectional – Material and methods:• 30 had unilateral agenesis of upper third molar. • 57 dental students • 27 had agenesis of one lower third molar. www.indiandentalacademy.com
  • 70. • Plaster casts were used to measure – Space conditions on both sides of arch. – M – D asymmetries of lateral arch segments. – Midline displacement. www.indiandentalacademy.com
  • 71. • CONCLUSION: – Concluded that presence of third molar appeared to exert some influence on development of dental arch but not to the extent that would justify extraction of 3rd molars. www.indiandentalacademy.com
  • 72. • 2. Vego (1962) – Design of study – Longitudinal. • Material and Methods: – – – – – – Sample size : 65 subjects. 40 individuals with lower third molars present. 25 patients with lower third molars congenitally absent. Amount of crowding measured at two time intervals. 1st measurement – At 13 years of age. Another measurement at average age of 19 years. www.indiandentalacademy.com
  • 73. • Criteria for Measurement of Crowding: – Closure of space. – Slipping of contacts causing rotation or adverse movement of teeth. • RESULTS: – Vego found in all 65 cases arch perimeter showed a decrease from 1st to the 2nd casts. www.indiandentalacademy.com
  • 74. • CONCLUSION: – Erupting lower third molars can exert a force on the neighbouring teeth and also indicated that there are multiple factors involved in crowding of the arch. www.indiandentalacademy.com
  • 75. STUDIES INDICATING A LACK OF CORRELATION BETWEEN MANDIBULAR 3RD MOLARS AND POST RETENTION CROWDING: • 1. Kaplan (1974): – Materials and Methods: • Pre treatment, post treatment and 10 years post retention study models of 75 orthodontically treated patients. • Lateral Cephalograms. www.indiandentalacademy.com
  • 76. • Sample was divided into 3 groups : • • • 30 persons – all 3rd molars in good occlusion. 20 persons – bilaterally impacted 3rd molars. 25 persons – bilateral agenesis of 3rd molars. www.indiandentalacademy.com
  • 77. • CONCLUSION: – Some degree of crowding occurred but there was no significant difference between the 3 groups. According to Kaplan the theory that 3rd molars exert pressure on the teeth mesial to them could not be substantiated. www.indiandentalacademy.com
  • 78. I. TIMING OF TREATMENT • TIMING OF TREATMENT FOR CLASS II MALOCCLUSIONS • : Two general strategies prevailing today for timing of treatment for Class II malocclusion: • 1 ) two phase treatment • 2 ) one phase treatment www.indiandentalacademy.com
  • 79. 1. TWO PHASE TREATMENT • Correction is achieved in two phases. – First phase : during preadolescence (8 – 11 years). - EARLY TREATMENT – Second phase: More definitive intervention during adolescence (12–15yrs.) designed to finish and detail the occlusion. www.indiandentalacademy.com
  • 80. ONE PHASE TREATMENT: • Entire correction is accomplished in one-phase of active treatment during the adolescent years. www.indiandentalacademy.com
  • 81. • EARLY TREATMENT: • Proponents of early treatment claim that : • 1. Rapid correction can be achieved as clinician has growth to work with. – a. Animal studies using FJO (Mc Namara 1973, Moyers et al, 1970, Stockli, 1971) and extraoral forces (Elder 1974, Droschl 1973) have clearly shown that : • Significant craniofacial modification can be effected in both adult and young animals. www.indiandentalacademy.com
  • 82. • Magnitude and rate with which these changes were achieved were greater in younger animals. • Clinicians have made empirical observation that best orthopaedic results are obtained when growth is most active and that the juvenile period has greater growth on the average at its beginning. • Skeletal Correction can be achieved with minimal dentoalveolar change. • Early data consisted of animal experiments demonstrating histologic and radiographic evidence of increased growth of Condylar Cartilage when mandible was held in a forward position. www.indiandentalacademy.com
  • 83. • • Eg: Petrovic and coworkers (1967, 1969) using rat as models. Baume (1961), McNamara (1987) using primates. • The animal studies of 1960s and 1970s created enormous enthusiasm in the professional community and played an important role in rapid acceptance and use of functional appliances in USA that had been largely ignored up until that time. • These were supported by studies on humans using both the Activator (Domisch, 1972) and the Frankel appliance (Mc Namara et al, 1985) although increases are more subtle. www.indiandentalacademy.com
  • 84. • Patients are more cooperative during the pre-adolescent years. • Reduces the treatment time in fixed appliances thus reducing the iatrogenic risks associated with these appliances. Eg : Enamel decalcification. • • • • Root resorption. Pulpal injury. Damage to periodontium. • Final result after treatment in teens is more stable. • Less need for extraction of permanent teeth. www.indiandentalacademy.com
  • 85. LATE TREATMENT : (ONE – PHASE TREATMENT) • Advocates of late treatment claim that : – 1. Greater proportion of dentoalveolar change as compared to skeletal change with use of Functional appliances: – e.g: Functional regulator and activator correct Class II malocclusions by encouraging substantial dentoalveolar change. (Freunthaller, 1967, McNamara 1985). Both reduce overjet by proclination of lower incisors. (Mc Namara 1985, Creekmore 1983, Ahlgren 1976, Pancherz 1976). www.indiandentalacademy.com
  • 86. • 2. Amount of Skeletal Change Achieved Clinically by Use of Functional Appliances: • Animal studies in 1960s and 1970s created lot of enthusiasm about efficacy of Functional appliances. www.indiandentalacademy.com
  • 87. • In 1970s and 1980s various investigators conducted retrospective clinical studies. A number of these studies demonstrated that : – Some average modest increases in mandibular growth (2 – 4mm/yr) during treatment with functional appliances. (Pancherz 1979, McNamara, 1990). www.indiandentalacademy.com
  • 88. – Other investigators didn’t consider the effect of functional appliances on quantitative lengthening of mandible to be clinically significant (Woodside et al, Stockli 1973, Creekmore 1983, Gianelly 1983, Nelson 1993). – In addition, there still is uncertainity whether discernible mandibular growth acceleration is merely temporal and doesn’t result in an absolute final gain in mandibular length (Tulloch et al, 1998). www.indiandentalacademy.com
  • 89. • Advocates of delayed treatment feel precious “Cooperative potential” is consumed by early treatment approaches leaving less for final stage. • Cost – Risk / Benefit Analysis: • The major costs of early treatment may be associated with tissue damage, abnormal function, abnormal growth, treatment time and its related financial burden. www.indiandentalacademy.com
  • 90. • Anthony A. Gianelly in his article “One phase versus two phase treatment” in AJO – DO (1995) says that : – Crowding can be resolved in upto 84% of all patients with treatment that need be started no earlier than the late mixed dentition stage of development because space necessary for alignment in most patients with crowding is gained principally by “E” space control. www.indiandentalacademy.com
  • 91. • Class II Malocclusions: • At least 90% of all children with Class II malocclusions with or without crowding can be treated successfully in one phase which lasts between 2 – 3 years. • Eg : Distallization of Maxillary molars. • Routinely successful at this age because molars can be moved distally 1-2mm per month during this time period and mandibular growth is apparently sufficient to aid in correcting the Class II malocclusion. www.indiandentalacademy.com
  • 92. CONCLUSION: • “PHILOSOPHY” AND EVIDENCE BASED ORTHODONTICS: • Within this controversial situation we as doctors, as orthodontists, we have an obligation to be clinical scientists providing the best evidence – based services for our patients. • Why, then this in this “age of science”, do we still hear from time to time about necessity of embracing a treatment “philosophy” in orthodontics ? • In orthodontics, we seem to be witnessing nothing less than a throwback to the proprietary era, when someone’s crafty “philosophy” or “School of thought” could masquerade as a new science. That may have been acceptable pitch 90 years ago, but now thankfully we have sounder choices. www.indiandentalacademy.com
  • 93. • In this factual evidence based age that is ours, do we really need anyone’s belief system as cornerstone of our diagnostic treatment methods ? • Philosophy can be a wonderful guidepost for our personal lives and our spiritual fulfillment, yet that doesn’t qualify it as a scientific basis for delivery of the best orthodontic patient care. www.indiandentalacademy.com
  • 94. BIBLIOGRAPHY • . • Profit WR : Contemporary Orthodontics, ed 3, St. Louis, 2000, Mosby • Fletcher, G.G.T : The Begg appliance and Technique, London, 1981, John G. Wright. PSG, Inc. • Salzmam JA : Practice of Orthodontics, Vol. 2, Philadelphia, J.B. Lippincott Co. • Melsen Birt : Current Controversies in Orthodontics, Chicago, 1991, Quintessence Publishing Co., Inc. • Spalding Peter M : Treatment of Class II Malocclusions. In Bishara SE (Editor) : Text book of Orthodontics, ed 1, Philadelphia, 2001, W.B. Saunders. Begg PR, Kesling PC : Begg Orthodontic Theory and Technique, ed 3, Philadelphia, 1977, WB Saunders. www.indiandentalacademy.com
  • 95. • Joondeph DB, Riedel RA : Retention. In Graper TM, Vanarsdall RL (Editors) : Orthodontics : Current Principles and Techniques, ed 3, St. Louis, Mosby. • Graber TM, Rakosi T, Petrovic AG : Dentofacial Orthopaedics with Functional Appliances, Ed. 2, St. Louis, Mosby. • Rinchuse DJ & Rinchuse DJ : Ambiguties of Angle’s Classification, Angle Orthod 59 : 295 – 298, 1998. • Bernstein L : Edward H. Angle Versus Calvin S. Case : Extraction Versus Non extraction. Historical revisionism. Part II, AJO – DO 102: 546 – 551, 1992. • Moore AW : A Critique of Orthodontic Dogma, Angle Orthod 39 : 69–82, 1969. • Bramante M.A : Controversies in Orthodontics, Dental Clinics of North America. 34 : 91 – 102, 1990. www.indiandentalacademy.com
  • 96. • Schumth : Milestones in the development and practical application of functional appliances. AJO 84 : 48 – 53, 1983. • Gianelly AA: One Phase versus two-phase treatment, AJO – DO 108 : 556 – 559, 1995. • Gianelly AA: On Current Issues in Orthodontics. JCO 30: 439 – 446, 1996. • Bishara SE: On Growth and Orthodontic Treatment. JCO 32: 361 – 367, 1998. • Johnston LE. Jr. : On Orthodontics and Scientific Method. JCO 27 : 201 – 206, 1993. • Bishara SE : Third molars : a dilemma ! Or is it ? AJO – DO 115 : 628 – 633, 1999. • Riedel RA : Review of Retention Problem, Angle Orthod 30 : 179 – 199, 1960. • Shrestha BK : Extractions in Orthodontics, Seminars in Orthodontics, 2002, CODS, Mangalore. www.indiandentalacademy.com
  • 97. • King G.J et al : Timing of treatment for Class II Malocclusions in Children : a literature review, Angle Orthod. 87 – 97, 1990. • McLaughlin and Benett : The extraction – non extraction dilemma as it relates to TMD, Angle Orthod. 175 – 186, 1995. • Peck Sheldon : “Philosophy” and evidence based Orthodontics, Angle Orthod 67 : 403, 1997. www.indiandentalacademy.com
  • 98. www.indiandentalacademy.com Leader in continuing dental education www.indiandentalacademy.com

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