Surgical Therapy
1. Introduction
Ortho-surgical protocols are part of multidisciplinary care. Indeed, the different protagonists of a therapeutic success can be on the one hand the orthodontist, on the other the odontologist in the case of surgical procedure under local anesthesia or the maxillofacial surgeon, the anesthesiologist in the context of interventions requiring general anesthesia, sometimes also the prosthetist. The surgical protocol must be the result of good consultation within the team.
2. Age decision making (timing).
The care of a patient will vary greatly depending on their age.
For example, for implants, you have to wait until you are 18-20 years old.
Dental disinclusions can be performed as soon as obtaining intra-arch anchorage is deemed satisfactory.
DDS germectomies: do not perform them too early because there is a gain in space distally from the 7th to the age of 17-18 years.
Age in orthognathic surgery protocols also raises debates. This choice can be made based on 2 parameters:
- The effect of injuries on the patient’s psychological profile
- The effect of surgery on growth.
GOUDOT proposes a chronology based on each dysmorphosis:
- For skeletal class II: surgery can be considered earlier (from 13 years old once the growth spurt has passed)
- For skeletal class III: it is necessary to wait until the end of mandibular growth
- For vertical excesses and vertical deficiencies, the end of bone growth
- For endomaxillae, early surgery allows for more stable expansion by limiting dental vestibuloversions and an improvement in respiratory dysfunctions.
Surgical Therapy
3 – The patient’s duty to inform.
This duty arises from the principle of informed consent of the patient who must be informed of the diagnosis, the different therapeutic options as well as the possible consequences of these acts.
Beyond this medico-legal aspect, a real listening process must take place between the practitioner and his patient in order to avoid any gray areas regarding the management of dysmorphoses.
4- Planning of orthodontic-surgical treatment:
The predictive analysis consists of a dialogue between orthodontist, occlusodontist and maxillofacial surgeon around “set-up” simulations which allow:
- To locate the seat of the anomaly
- To specify the intervention site
- To quantify movements
- To view all the planned changes
- To inform the patient
4.1 The cephalometric set-up
This set-up can be carried out at the beginning of treatment. The visualized objectives of RICKETTS or the analysis of SASSOUNI are classically used. They are based on 5 steps:
- The layout of stable structures
- Determining the position of the upper incisor
- The outline of the mandible
- Symphyseal modification
- The profile outline.
The most common technique is to trace the desired modifications on a 2nd layer using different colors for each operating time.
4.2 The set-up on castings
For MANIERE et al. This “cast surgery” is a crucial step for:
- Objectify the diagnosis and visualize the planned movements
- Evaluate the quality of orthodontic preparation
- Allowing good understanding by the patient
There are various methods for mounting on an articulator, including one that consists of separating the dental arches from their base and then moving them according to the surgery with wax; the toothed segments are finally secured with plaster. In order to optimize this assembly, the tracing of the axis of symmetry of the face and the free edge of the upper lip at rest is carried out.
4.3 The photography setup:
The Margolis technique allows the profile photograph and the cephalometric tracing to be superimposed on a single image. It is thus possible to simulate bone displacement (cephalometric setup) and to construct a photograph approaching the result.
Great caution is necessary since the movements of soft tissues are not the same as those of the bony infrastructure.
4.4 Surgical-occluso-orthodontic symbiosis:
4.4.1 Role of the orthodontist:
Pre-operative orthodontics:
-Management and correction of intra-arch problems: DDM rotation inclusion diastema, etc.
-Alveolar decompensation: step which aims to eliminate alveolar compensations thus aggravating the base shift in order to know the amplitude of the movements to be carried out.
– Ensure congruence (coordination) of the arches: harmonize arch shapes, manage transverse discordance and obtain optimal alignment
-Provide an anchor for the post-operative retention device: surgical arches, rectangular arches of large sections with welded pins which constitute a reliable anchor for bi-maxillary blocking and respectful for the periodontium
Intraoperative orthodontics:
The orthodontist’s action is limited to mounting and dismounting the arches used by the surgeon to perform the bimaxillary blockade.
Post-operative orthodontics:
The main role of the orthodontist is to perfect the occlusion, because surgical movements do not allow occlusal relationships in PIM, with exactitude. Undertaken gently from the removal of the wire approximately 6 weeks after monitoring associated or not with neuro-muscular rehabilitation for at least 1 year. This stage typically lasts 6-8 months, because most of the finishing touches are already done in pre-operative orthodontics
Post-surgical orthodontic goals
They are generally identical to those sought in conventional orthodontics:
- Find the root parallelism if a divergence has been made
- Establish correct and stable intercuspation
- Close residual spaces
4.4.2. Role of the surgeon
Responsible for the surgical procedure and post-operative follow-up, he maintains three traditions:
- Occlusal tradition : which seeks ANGLE canine and molar class I, accepts therapeutic class II and avoids class III
- Functional tradition: it must ensure that the functions of breathing, phonation, mastication are restored or improved, the physiology of the temporomandibular joint (TMJ) under the dependence of a neuromuscular balance is preserved.
- Aesthetic & psychological tradition : the first reason for consultation is aesthetic
According to Laufer, 56% of unsightly patients require real social rehabilitation.
4.4.3. Role of the occlusodontist
The quality of the orthodontic preparations allows us to consider combined surgery under the best possible conditions and to hope for a balanced static and dynamic occlusion at a later date.
- Study the patient’s static and dynamic occlusion
- Must make DAM diagnosis before pre-surgical orthodontic treatment
- Ensure ATM neutrality throughout treatment
- Production of retention gutters.
5- What surgical indications can the orthodontist make?
5.1 Orthognathic surgery
5.1.1 Maxillary segmental osteotomies
WASSMUND osteotomy
Described in 1935, it allows the mobilization of the maxillary incisor-canine sector and movements of recoil, ingression, egression and advancement.
Indications :
- Correction of superior pro-alveolus after extraction of 14 and 24
- Correction of superior infra-alveolus not associated with anterior vertical excesses
- Correction of upper incisor supra-alveoli associated with a class II
- Correction of an overbite associated with a gummy smile
Surgical Therapy
SCHUCHARDT osteotomy
Described in 1942, it allows the mobilization of the maxillary premolar-molar sectors.
Indications :
- Posterior vertical excess and labial incompetence without gummy smile
- Anterior gape
5.1.2 Mandibular segmental osteotomies
KÖLE osteotomy
This is the best known. It consists of mobilization of the incisor-canine fragment.
Indications :
- Ingression bone : Lower incisor intrusion to correct an overbite
- Recoil : Correction of pro-alveolus after premolar extractions
- Egression occlusion : Correction of incisor gap of mandibular origin.
Surgical Therapy
Surgical Therapy
5.1.3 Total maxillary osteotomies: LEFORT I type
Named thus because of the similarity with the fracture line of the same name, which completely freed the maxilla by osteotomy of the pterygomaxillary suture.
Indications :
- Retreat and especially advance in the event of retrusion of the middle floor
- Impaction in the case of anterior vertical excesses
- Lowering (epaction)
- Sequelae of cleft lip, alveolar cleft palate.
Surgical Therapy
LEFORT II type
Indications:
- Total aplasia of the middle floor (nasal pyramid, maxillary, malar region)
- BINDER syndrome
- Sequelae of facial clefts.
LEFORT III type
Indications:
- Congenital cranial aplasias with hypertelorism and exophthalmos (Apert and Crouzon syndromes)
5.1.4 Trans-ramal osteotomies (OBWEGESER – DALPONT)
Described by TRAUNER- OBWEGESER in 1955, modified by DALPONT in 1959, its objective is the cleavage of the ascending branches by separation of the internal and external cortices which can allow mobilization of the dentate segment of the ascending branch in the three directions of movement space:
- Of advance or retreat
- Of elevation or lowering
- Of derotation
Indications :
- Mandibular prognathia and retrognathia associated or not with vertical anomalies
- Mandibular laterognathia
Surgical Therapy
5.2. ATM surgeries
- indicated in cases of acondylia, hypo or hypercondylia or retromandibulia.
- Condylotomy / Condylectomy: partial or total resection of the condyle
- Retrocondylar cartilaginous wedge: allows permanent propulsion of the mandible by interposing a uni- or bilateral extra-articular cartilaginous wedge in the retrocondylar space of the mandible, thus correcting retromandibulia.
Surgical Therapy
5.3 Distractions
It is an orthopedic and surgical procedure causing bone lengthening by osteogenesis. This technique can be applied in all cases of insufficient development of the orofacial sphere.
Activation is 1mm/day with a latency of 4 to 7 days and a retention period of 6 to 8 weeks.
This technique involves cutting a bone in order to form a bone callus and attaching a metal device to the two segments of this bone to stimulate the osteogenic power.
Depending on the location of the distractor, it allows: lengthening, mandibular widening, maxillary advancement and expansion.
5.4. Profile harmonization surgeries
5.4.1 Rhinoplasties
Considered alone, it must be performed on a subject with a balanced face with a harmonious facial height. HADJEAN, NEGRIER do not recommend it in cases of uncompensated dysmorphoses, thus in class III with retrusion of the maxilla, a rhinoplasty could prove catastrophic.
5.4.2 Genioplasties
Sagittal direction
Advancement genioplasty in case of retrogenia
Reversal genioplasty in case of progeny.
Vertical direction
Lengthening genioplasty in class I or II hypodivergent cases with supraclusion (need to interpose an iliac bone graft or a hydroxyapatite block).
Reduction genioplasty in the vertical excesses of the lower third of the face with high and flat chin.
Transverse direction
In facial asymmetries when the asymmetry of the chin persists after correction of the dysmorphosis (laterognathya, hypercondylia)
Surgical Therapy
Surgical Therapy
5.5 Periodontal surgery
If the orthodontist does not prescribe certain primary interventions, he must be aware of them in order to establish a chronology of multidisciplinary procedures.
Surgical Therapy
5.5.1 Periodontal bone surgery
- Canine disinclusion surgery
- Conductive alveolectomy for retained teeth
- Accelerated orthodontic treatment by alveolar corticotomy: Alveolar corticotomy consists of a surgical intervention on the bony cortex around the teeth to be moved.
It causes a decrease in the density of the medullary bone and an increase in bone turnover.
5.5.2Mucogingival periodontal surgery
Its objective is to correct the morphology, position and/or quality of the gingival tissue.
Another indication is labial frenectomy which removes the obstacle to closing a diastema; in the maxilla, it is recommended to wait for the development of the canines.
5.6. Soft tissue surgery
Glossectomy/Glossotomy: surgery limited to true macroglossia , which consists of reducing the lingual volume according to different designs, notably an anterior V, teardrop, central design or even lateral edges.
Lingual frenectomy which frees the tongue from its low position, and at the same time eliminates the tractions of the genioglossus on the marginal periodontium.
5.7 Dental element surgery
It concerns extractions whose indication is established at the time of diagnosis depending on the dysmorphoses, the location of the DDM, the decay of the teeth.
It also concerns a very specific protocol linked to piloted extractions which allow guidance of the eruption.
This also includes germectomies. Germectomies mainly concern wisdom teeth, premolar germectomy is no longer recommended due to the invasive nature of this procedure.
Conclusion
To successfully carry out orthodontic therapy, the use of a multidisciplinary team is increasingly desirable in order to optimize the result.
Since orthodontic-surgical procedures are not one-off actions, constant communication between the different protagonists will guarantee the patient’s investment in this therapeutic path. In this spirit, surgical-orthodontic protocols then allow, in the interest of the patient, to mutually push back the limits of each.
Good oral hygiene is essential to prevent cavities and gum disease.
Regular scaling at the dentist helps remove plaque and maintain a healthy mouth.
Dental implant placement is a long-term solution to replace a missing tooth.
Dental X-rays help diagnose problems that are invisible to the naked eye, such as tooth decay.
The dentist uses local anesthesia to minimize pain during dental treatment.