Dr Robert Drummond BChD, DipOdont Ortho, MChD(Ortho), FDC(SA) Ortho Canad Inn Polo Park Winnipeg 2015
Severely compromised FPM with poor prognosis Children often present with a developing dentition affected by one or more first permanent molars of poor prognosis, which may require their enforced extraction
In the right circumstances, first permanent molar extraction can be followed by successful eruption of the second permanent molar to provide a suitable replacement, and ultimately third molar eruption to complete the molar dentition, although this is not guaranteed
Should the compromised FPM be extracted as soon as possible, or should it be temporarily restored and extracted later? If the prognosis of one FPM is poor, is extraction of the other FPMs required?
National clinical guidelines for the extraction of first permanent molars in children. M. T. Cobourne, A. Williams and M. Harrison. British Dental Journal, Volume 217 no. 11, DEC 5 2014. The best available evidence
Condition that will influence the clinical management Comprehensive patient examination Importance of Panoramic Radiograph Diagnosis Definitions Balancing Extraction Compensating Extraction Ideal Timing Orthodontic Opinion Guideline for elective FPM extraction in children with different malocclusions General rule Class I with no crowding Class I with crowding Class II with no crowding Class II with crowding Class III Trial Case Conclusion
The individual patient circumstances Maxilla or Mandible The extent of crowding and the presenting malocclusion If the patient will require or desire orthodontic treatment in the future, the timing and extraction pattern should be tailored to achieve the optimal outcome for that individual patient The stage of dental development Any other permanent teeth absent, severely displaced or of doubtful prognosis Other pathology
Facial analysis Facial Symmetry Facial Proportions Profile Lips Smile Intra-oral analysis Radiographic examination Panoramic radiograph
Before any decision is made, a panoramic radiograph of good quality is needed to show that all teeth are present, in good condition i.e. not hypoplastic, and are well placed for eruption
Malocclusion Antero-posterior (AP) Transverse Vertical Crowding Amount Anterior or posterior Arch Symmetry Dental development Contemporary Orthodontics, 5 th edition. William R. Proffit, Henry W. Fields
Balancing extraction Is the removal of the first molar on the other side of the same arch Compensating extraction Is the removal of the first molar on the same side in the opposing arch
In the maxilla, an unerupted 7 with a decent developmental position at the time of extraction of the FPM, generally ensures a good occlusal position
In the lower arch timing of the extraction is more important for successful eruption of the 7 s Chronological age between 8 and 10, after eruption of the lateral incisor s and before the eruption of the second molars and /or second premolars Also if there is radiographic evidence of early dentine calcification within the second molar root bifurcation
Extractions before the age of 8 should be avoided: As normally, there is no radiographic evidence of third molar development Second premolars can escape from its position between the roots of the e s and therefore drift distally Labial segment can retrocline, increasing the overbite and overjet
Extraction during the later stage of second molar development Mesial tipping Rotation Spacing Poor occlusal contact
Ideally an orthodontic opinion should be obtained before extraction of any permanent tooth; if possible from the orthodontist who will be responsible for future treatment Temporise or restore and refer This is not always possible if there is sepsis or pain
Guideline for Elective FPM Extraction in Children with Different Malocclusions General rule Class I with no crowding Class I with crowding Class II with no crowding Class II with crowding Class III
As a general rule, if in doubt, get the patient out of pain, try and maintain the teeth and refer for a specialist orthodontic opinion In recent years, fixed anchorage devices have become more routinely available in orthodontics and these provide further options in the management of first permanent molar extraction cases, particularly in terms of anchorage reinforcement and space closure
Aim for extraction at the optimal time for eruption of the second permanent molars into a good position Do not balance unilateral first permanent molar extraction in either the upper or lower jaws if the first permanent molars are healthy
If the lower first permanent molar is to be lost, the opposing upper first molar can over-erupt as a result Prevent over-eruption with a simple appliance Compensating extraction of the upper first molar can be considered if this tooth is likely to be unopposed for a significant length of time
If over eruption did occur, molar intrusion with TAD s during full fixed orthodontic treatment is possible
If the first molar on the lower arch is to be extracted and the opposing upper first molar has a poor prognosis, consider extraction of this tooth
If the upper first molar is to be extracted, do not compensate with extraction of the lower first molar if it is healthy
16 54 lost Middle mixed dentition with caries on several teeth All permanent teeth present, not all erupted Minimal crowding Early loss of 54 with space maintainer Mesial drifting 16 localized space shortage, 1ste Quadrant Heavily restored 16 with questionable prognosis Extensive caries 46 = poor prognosis ( Dentist requested opinion on the XLA) Advance development of the 7 s - 2/3 root formation Radiographic evidence of the development of all four third molar
16 54 lost Middle mixed dentition All permanent teeth present, not all erupted Minimal crowding Early loss of 54 with space maintainer Mesial drifting 16 localized space shortage, 1ste Quadrant Heavily restored 16 with questionable prognosis Extensive caries 46 = poor prognosis ( Dentist requested opinion on the XLA) Advance development of the 7 s - 2/3 root formation Radiographic evidence of the development of all four third molar
16 54 lost Extraction 46, 16 & 55 NB! Due to the advanced development of the 47, extraction of the 46 could result in poor occlusal contact for the 47 with increased mesial tipping and spacing and a higher need for orthodontic correction
BUCCAL SEGMENT CROWDING ANTERIOR CROWDING
BUCCAL SEGMENT CROWDING Aim to extract at the optimal time to allow eruption of second molars into a good occlusal position, which should also provide some relief of crowding If the buccal segment crowding is bilateral, consider balancing extraction of the contralateral first permanent molar to provide suitable relief, particularly if there is any question regarding the long-term prognosis for this tooth Compensating extractions of upper first permanent molars can be considered to relieve premolar crowding
Buccal crowding and severely compromised 46 and 36
Extraction of the 46 and 36 With 7 s replacing the 6 s with good axial inclination and occlusal contact
All four permanent molars were compromised and subsequently extracted, which resulted in 7 s replacing the 6 s with good axial inclination and occlusal contact Relieve of the buccal crowding
ANTERIOR CROWDING In the presence of crowding in the labial segments, little spontaneous relief is provided by first permanent molar extraction First permanent molar extractions can be delayed until the second permanent molars have erupted and then the extraction space can be used for alignment with fixed appliance Alternatively, first permanent molars can be extracted at the optimum time and the crowding treated once in the permanent dentition If premolar extractions are likely to be required at this stage, the third molars should be present
Hypermineralized upper & lower FPM with secondary Caries
Moderate upper crowding Potential eruption problems with upper canines Severe lower crowding Class I buccal occlusion left and right Mandibular midline 3mm to the right Unerupted 42 & no space Normal overjet and overbite
?? Confirm possible ectopic 13 and 23 and possible impaction of the 43 Radiographic evidence of only the 48 and 28 Beginning root formation on the 7 s
x x x x Extract the first permanent molars at the optimum time to allow for the permanent second molar to replace 6 s Resolve the crowding, once in the permanent dentition For which you will need additional four premolar extractions : which does not make this option ideal There is also no clear evidence on the presence of two of the third molars which is a contradiction for this option
x x x x Delay first permanent molar extractions until the second permanent molars have erupted and then use the extraction space for alignment with fixed appliance
x x x x Option 2 Temporarily restore the 6 s Wait for the eruption of the 7 s After eruption of the 7 s extraction of all four FPM Full fixed orthodontic treatment with additional anchorage
The extraction of first permanent molars in Class II cases are more difficult to plan, particularly with regard to the upper first permanent molars The main complicating factors in the upper arch is the need for space to correct the incisor relationship
Growth modification / non-extraction Fixed Removable Class II Camouflage Extraction upper 4 s and or lower 5 s Distalization Combination Growth modification & Extractions
Class II Growth modification / non-extraction Fixed Removable Extract the first permanent molars at the optimum time to allow for the permanent second molar to replace 6 s The patient should be counselled however, that additional premolar extractions in the upper arch might be required in the future to create space for overjet correction if the GM is unsuccessful
Class II Camouflage Extraction upper 4 s and or lower 5 s Distalization The upper first permanent molars should be temporised or restored so that their extraction can be delayed until the second permanent molars have erupted The resultant extraction space can then be used to correct the malocclusion with fixed appliance The extraction of the lower first permanent molar should be carried out at the ideal time for successful eruption of the second permanent molar in its place
Camouflage Extraction upper 4 s and or lower 5 s Class II Combination Growth modification & Extractions Distalization The upper first permanent molars should be temporised or restored so that their extraction can be delayed until the second permanent molars have erupted The resultant extraction space can then be used to correct the malocclusion and crowding with fixed appliance The extraction of the lower first permanent molar should be carried out at the ideal time for successful eruption of the second permanent molar in its place if the crowding is in buccal segment If the crowding is anterior delay the extraction until after the eruption of the 7 s
Class III cases are often difficult to manage and ideally require the opinion of a specialist orthodontist before any first permanent molars are extracted As a general rule, extraction of maxillary molars should be avoided if at all possible, while balancing and compensating extractions are not recommended in Class III cases
A tendency toward increased residual spacing has been described in the lower arch of Class III cases following first permanent molar extraction
Treatment planning for the enforced extraction of first permanent molars can present a complex problem, particularly in the presence of an underlying malocclusion I hope these guidelines will be useful in your decision making If you have any questions you are welcome to contact me at robert.drummond@umanitoba.ca