11 Feb Surgical Extrusion Technique for Ferule Effect Enhancement
Performed by: Cirimpei Vasile
A late 20’s male patient addressed with a chief complaint of the fractured tooth. Patient recalls he had a root canal treatment and eventually a full jacket crown one month ago. The patient presented a high interest in saving the tooth and considered the implant to be reluctant as a treatment option.
Upon the data collected and clinical status there where 2 major ways in solving the case:
1. Extract the root due to severe ferule effect debilitation. A further removable single unit prosthesis, either a 3 unit bridge with the first molar and first premolar serving as abutments to solve the missing tooth could be proposed
2. Preserve the root for future rehabilitation of the missing clinical crown. Obviously, the ferrule effect needed to be managed. One of the ways to do so is to dislocate apically the gingival margin and expose sound tooth structure, namely – a surgical crown lengthening. Though it is a validated treatment, SCL has a lot of disadvantage. First, it is resective in nature, that does not necessarily means it is wrong, however, the resective nature of SCL can induce the further drawbacks – it has high potential of transforming a high caries risk patient in a periodontopathic one, uneven zeniths, loss of papilla, lower the CAL, decrease the biomechanics etc. For these particular reasons, a true deep margin elevation can be a better clinical scenario, this true deep margin elevation can be obtained by extruding the margins of sound tooth structure coronally/occllusally. The extrusion can be performed by means of orthodontic extrusion, either by means partial surgical extrusion, the latter being the approach that was performed in this case.
It is obviously crucial to make a good case selection in order to obtain a good clinical result, considering that the more complicated the case is – the more it is exposed to the fragile variables. The SET can be a straightforward procedure if the following parameters are to be completed:
1. Long roots. Considering that the length of the root is to be “shortened” after surgical extrusion we have to take in account this crucial parameter. Medicine is not about recipes, however, a shorter then 11 mm root implanted into bone is a considered to be unfavorable for the procedure
2. Straight roots. Pivotant, tapered roots are considered to be the best. It is mainly related to the technical procedure of luxating the root in the socket. Usually, these roots present a relatively easy way of luxating, and most important the remaining root is not mechanically stressed during the procedure, and at the same less stress on the bone during luxation
3. Radiographic appearance of periodontal ligament should present no signs of ankylosis
4. In case there is evidence resembling AP, it would be recommended to address them prior to the extrusion time frame
After infiltrative anesthesia, using a luxator, the root was coronally displaced. At this stage, the root was stabilized in the socket solely by means of sutures (to be more precise modified interdental continuous suture). It is not recommended to use rigid splinting, in order to prevent the chance of ankylosis the root. After 8 weeks in most of the cases, the root will present sufficient mechanical stability to be restored properly.
#1 Preop intraoral status. Occlusal, buccal and palatal view
#2 Postoperative view. Oclusal, bucal and palatal view
#3 Preop periapical
#7 View at 23 days. At this stage, the tooth was restored and a temporary
#8 Schematic illustration showing evidence of ferule damaging with the horizontal finishing line. Blackline – the outline of the neighboring tooth. Blue line – the inner position of sacrificed dentin during endo sequence. Distance from Redline to blue line indicates the remaining dentin after the abutment was prepared. Distance from outer blue line to red line indicates the shoulder resulted with the horizontal finish line
#9 Intraoral view a 6 months
#10 Laboratory photographs showing the cast model and the vertical preparation of abutment and the final E max crown
#11 Delivery of the final crown. Intraoral view of the crown
#12 Bitewing and periapical in 2016, 6 months after SET
#13 Recall 3 years after Surgical Extrusion
#14 Recall in 2019