Review article Annals and Essences of Dentistry SERIAL EXTRACTION: IS IT A PANACEA FOR CROWDED ARCHES? * Radhika Chopra * Senior Lecturer, Karnavati School of Dentistry, Ghandhinagar ABSTRACT Serial Extraction or the guidance of eruption is an age old procedure to correct crowded arches and is still used in routine dental practice. But the efficacy of this procedure has always been controversial and it requires very precise clinical skill for a favorable outcome. This article presents a review regarding the proper selection of cases for serial extraction, its limitations and various adjuncts that are required to get good results. INTRODUCTION: Robert Bunon,23 in his Essay on Diseases of Intercepting certain forms of malocculsion Teeth, published in 1743, made the first reference with a preliminary program of serial extraction has a to early extractions. legitimate place in orthodontics. Dewel defines Linderer23(1851) wrote that quite often in serial extraction as an orthodontic treatment order to accommodate lateral incisor, one must strip procedure that involves the orderly removal of or extract deciduous canines and to relieve selected deciduous and permanent teeth in a subsequent crowding in buccal segments, removal predetermined sequence. of first premolar would be necessary. Serial extraction is based on the premise Strangely their early recommendations that in certain cases the orthodontist is confronted were ignored for nearly two centuries. It was not with a continuing discrepancy between total tooth until the 1947-48 Transactions of the European material and deficient arch length. He is presented Orthodontic Society had been published that the with a limited amount of basal bone, present or procedure was again presented. Working separately potential, in which to reposition rotated, malposed or during the early 1930’s and 1940’s, Switzerland’s blocked out teeth. Any effort to enlarge that base to Rudolf Hotz and Sweden’s Birger Kjellgren accommodate all the teeth far too often is rewarded independently arrived at extraction sequences that with relapse and failure. were identical. Since there was little communication It demands a fine sense of clinical during World War II, neither knew of the work of the diagnostic skill, perhaps more than in any other other. Kjellgren used the term ‘serial extraction’. area of orthodontic practice. Although it is Hotz suggested the equally acceptable and perhaps deceptively simple in appearance and application, the more descriptive term of ‘guidance of dental irreparable damage can be done when it is eruption by means of extraction’. These men urged improperly applied. The orthodontic responsibility is a cautious rather than precipitous approach to all to differentiate between (1) those cases that will extraction decisions. respond to ideal treatment with a full complement of These same words of warning against teeth and (2) those that must submit in the indiscriminate extractions were stressed by beginning to compromise measures if relapse and a America’s Dewel5 in his 1954 article based on his time consuming second period of treatment with identical extraction sequence that also had its origin extraction are to be avoided. in the mid – 1930s. Still later Tweed suggested the HISTORY: term ‘preorthodontic guidance’23. The procedure goes back to 18th century – Nance presented clinics on his technique of principally to two Frenchman Bunon and Bourdet. ‘progressive extraction’ in 1940’s and has been They were among the first of several early writers to called the Father of serial extraction philosophy in describe the removal of certain deciduous and the U.S.23 permanent teeth in under developed arches to give the remaining teeth acceptable functional relations. Vol. - II Issue 2 April – June 2010 100 100 Review article Annals and Essences of Dentistry 21 REVIEW OF LITERATURE Maj and Luzi (1960) suggested that serial Selection of cases: extraction should not be prescribed in those cases Dewel4 suggests that serial extraction can in which alveolar growth increments can be be applied in certain Class II and Class III successfully stimulated and a good long lasting irregularities but almost invariably only as a part of correction can be achieved with a full complement treatment already in progress. In class I serial cases of teeth. 23 active orthodontic treatment more often is According to Mayne (1968), if the postponed until a later date and frequently it can be crowding is extremely severe, with irreparable omitted entirely. He stated that mandibular arch is insults occurring to the investing tissues, then logic the final diagnostic guide, with particular emphasis demands the early removal of deciduous cuspids, permitting the most rapid unravelling of the crowded on the harmonious relation of the mandibular incisor teeth and their greatest lingual adjustment, both to the basal bone. Slight irregularity or moderate these accomplishments will improve investing tissue crowding are not abnormal but extreme crowding, health. gingival recession and premature loss of deciduous Profitt28 writes that only when there is mandibular canines are not acceptable deviations extreme severe crowding of 10mm or more is there from the normal. a chance that a reasonably satisfactory result can According to Lloyd20(1956) patients with be achieved by serial extraction alone. short arch lengths or very short intercuspid width 3 Dewel (1969) concluded that an authentic would be suitable cases for serial extraction. He serial extraction case has markedly irregular advised serial extraction to be done in all types of anterior teeth, premature loss of one or more of the class I malocclusion and class II div I malocclusion deciduous canines, various median line deviations, that show a severe lack of arch length or severe impacted or displaced lateral incisors, a gross lack of intercanine space in both jaws to reduction in arch length and frequently, gingival accommodate the incisor teeth in non rotated recession and alveolar destruction along the labial position. They are further characterised by a good surfaces of one or both the central incisors. facial profile, the overbite ranges from slight to Cephalometrically, the typical class I severe and age of patient is somewhere between 6 extraction case presents a flat or straight facial and 9 years. pattern and the incisors are vertical and in a more Malocclusions that have lingually locked acceptable relation to the N-Pogonion facial plane. maxillary incisors i.e. anterior crossbite or buccal Giorgio Maj 22(1970) advocated the teeth in crossbite or that lack occlusion but show removal of deciduous canines when lack of space deficient arch length or lack of intercanine space are for mandibular incisor is greater than 2.5 mm. This mechanically treated for a short period until the would allow better alignment of incisors and prevent cross bite is changed and serial extraction is any tissue damage in the region of malposed continued. teeth.(Fig. 1) 31 Bimaxillary protrusions show beneficial Ruff (1976) concluded that in class I results from serial extraction procedure. A lip mixed dentition cases, decision for serial extraction retracting exercise in these cases is helpful in the should be made only after the size of unerupted uprighting and lingual positioning of the incisors. It is teeth is determined and after at least one year of suggested that a headplate be used to supplement growth observations verified by cephalometric the diagnosis. analysis. Cases with a discrepancy of 4 mm or more still have a chance, if the growth potential is good. Another type of malocclusion where serial Cases showing a greater arch length discrepancy extraction can be helpful is that in which mandibular will generally become extraction cases. arch has sufficient arch length with excellently 26 Odenrick and Troeme (1985) proposed aligned incisors but in which the maxillary arch when cephalometric evaluation indicates an shows a decided lack of space for the erupting orthognathic or retrognathic profile, slightly hyper lateral incisors due to forward eruption of buccal divergent, with facial skeletal dimensions less than teeth rather than to lack of intercanine space. Early average, in a patient whose dental casts indicate removal of maxillary deciduous canines will prevent above average incisor width, serial or early the lingual locking of the maxillary permanent lateral extraction therapy is one of the treatment modalities incisors. that may be considered. Vol. - II Issue 2 April – June 2010 101 101 Review article Annals and Essences of Dentistry 23 Jacquelin and Berthet 16 (1991) proposed Bjork (1951) believes extraction of that serial extraction has limited indications which deciduous teeth for correction of crowding not need to be respected in order to preserve the child’s justified as it retards the basal mandibular growth. 4 future dental health. It is indicated for class I Dewel (1957) found that even when malocclusion with severe crowding or moderate authentic serial extraction is indicated, premature crowding associated with bimaxillary protrusion. removal of teeth involves the danger of retarding Borderline cases: future development in arches that already are 3 deficient. Also, prolonged absence of teeth in the According to Dewel (1969), borderline premolar region permits the tongue to flow into the cases generally have good facial patterns, space which results in a major problem in habit moderate loss of arch length, a good muscular correction during the active stages of treatment.