Functional Genioplasty in Growing Patients
Angle Orthodontist online early
I would like to share with you a reseach that Idid in the past few years on bone remodeling following genioplasty
See the article following the abstract.
ABSTRACT
Objective:
To evaluate the role of age as a moderator of bone regeneration patterns and symphysis remodeling after genioplasty.
Method:
Fifty-four patients who underwent genioplasty at the end of their orthodontic treatment were divided into three age groups: younger than 15 years at the time of surgery (group 1), 15 to 19 years (group 2), and 20 years or older (group 3).
Twenty-three patients who did not accept genioplasty and had a follow-up radiograph 2 years after the end of their orthodontic treatment were used as a control group.
Patients were evaluated at three time points: immediate preoperative (T1), immediate postoperative (T2,) and 2 years postsurgery (T3).
Results:
The mean genial advancement at surgery was similar for the three age groups, but the extent of remodeling around the repositioned chin was greater in group 1, less in group 2, and still less in group 3. Symphysis thickness increased significantly during the 2-year postsurgery interval for the three groups, and this increase was significantly greater in group 1 than in group 3.
Remodeling above and behind the repositioned chin also was greater in the younger patients. This was related to greater vertical growth of the dentoalveolar process in the younger patients.
There was no evidence of a deleterious effect on mandibular growth.
Conclusion:
The outcomes of forward-upward genioplasty include increased symphysis thickness, bone apposition above B point, and remodeling at the inferior border.
When indications for this type of genioplasty are recognized, early surgical correction (before age 15) produces a better outcome in terms of bone remodeling.
(Angle Orthod. 0000;00:000-000.) DOI: 10.2319/030414-152.1
Bravo! What a fabulous article.
Merci Dr Venditelli
Our conversation is interesting.
I was misunderstood … I thought you treated, for purposes interceptive growth, even nuanced skeletal deformities, submitted at the end of orthodontic treatment to genioplasty.
With this in mind, I wanted to know if those patients with eventual residual vertical growth, had maintained the morphological benefits introduced by the genioplasty and if ever there was need ( through time ) to repeat the surgery.
Of course you are welcome to Italy. Can you doubt it?
A warm greeting
Dr Chamberland
Thank you for your comprehensive reply, but I am afraid that I haven’t explained well. There is a basic misunderstanding.
When I was talking about ..” .Hyperdivergent”.. I was not referring to your case; I meant to refer to your experience with skeletal deformities hyperdivergent growth profile, in which the genioplasty was performed.
Your case is obviously not one of these. Then with regard to the “Unfavorable growth pattern”, in this case I was referring to your experience about a skeletal problem that gets worse in the vertical growth, canceling out the benefit produced by a possible genioplasty.
I was not referring to restrictions of growth produced by the surgical act; this is quite debated topic.
I’m sorry that our conversation was spoiled by this basic misunderstanding.
Having acquired that you haven’t treated surgical patients , it was still interesting to know this conceptual development of the technique.
Thank you for making the precison about hyperdivergency and unfavourable vertical growth problem.
Chances are that hyperdivergent growth profile, there would be a vertical maxillary excess and short ramus and anterior openbite. Such skeletal malocclusion are addressed differerently and are likely not cases suitable for genioplasty as an isolated procedure.
Patient that have such skeletal characteristics will likely benefit from bimaxillary surgery at the end of their growth period.
They may also benefit from miniscrew and intrusion of maxillary and mandibular buccal segment to get a counterclockwise rotation and closing of the bite.
If lip competency is not obtained with a genioplasty, it might not be a case suitable for genioplasty.
These exception are covered in the keynote lecture that I did from this article.
The keynote is not online yet. But if you invite me in Italy, it would be a pleasure for me to go.
With this answer, i wish i was able to resolve some of the misundertanding.
Cordialement,
Recevez mes salutations distinguées
The rationale of your study is interesting as well as all the interceptive surgery in growing patients.
1-Which patients have enrolled in the first group?
2-They were just “orthodontics” or also patients with skeletal deformities?
3-In the latter case have you enrolled surgical patients with hyperdivergent mandibular growth pattern ?
4-What has happened, in this case, with an clockwise unfavorable residual growth of the jaw?
5-it ‘was necessary to repropose the genioplasty?
6-I think the selection of candidates should be rigorous and based on growth perspectives.
I wished to know your opinion an experience in this sense .
Greetings
Thank you Dr Sajeva for your questions.
1- Patients enrolled: All patients had a cl I occlusion and had their orthodontic treatment completed or within 2-3 months of completion. This is true for the 3 experimental groups.
2- There was no other skeletal deformity than vertical excess at the symphysis or lack of AP chin projection or both.
3-Hyperdivergent? The mean FMA was 34,06° (gr 1), 32,46° (gr 2), 34,76° (gr 3), 31,97° (Gr control). There was no statistical difference between groups regard FMA.
4- Unfavourable growth pattern.
This is answered in the discussion: “Does repositioning the chin have a deleterious effect on mandibular growth? That is a valid concern and has been a major reason for delaying it until growth is essentially completed…In a growing individual with an indication for forward-upward genioplasty, data from our control group show that lip incompetency persists, facial convexity is maintained, bone resorption occurs at point B, and symphysis thickness has a tendency to decrease.
Our data show that the growth pattern do not change after a genioplasty, ie a vertical growth pattern do not become an horizontal growth pattern.
5- Repropose genioplasty.
No patient had to undergo a second genioplasty. However, if a patient have juvenile rhumatoid arthritis and has condylar resorption, he might benefit from an early genioplasty and a revision when growth is completed if a 2nd surgical phase is indicated.
6- Case selection: case selection was rigorous.
“For all subjects, the recommendation for genioplasty was based on clinical evaluation of the prominence and vertical position of the soft tissue chin relative to the lips and midface. Cephalometric data for pretreatment a-p chin deficiency relative to the lower incisors, the vertical distance from the incisors to the bottom of the chin, and the mandibular plane angle are shown in Table 1.”
Warm regards
Dr Sylvain Chamberland