So this surgeon talks about a whole lot of different jaw surgery topics, and it's a bit long/technical to read the whole thing. He does have some pretty good surgery results in there (the girl with the HA cheeks at the end, and the asymmetry cases are really impressive!). But anyway, this section caught my eye, as it's like an in-depth list of factors that could lead to relapse or a poor result.
That said, I'm sure every surgeon/ortho probably has their own protocols and ways of doing things, so don't take this as gospel, but this list might be helpful to some ppl.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6150705/7) If you could summarize 10 traps of surgical orthodontic treatment, what would they be?
I would divide the traps into presurgical, surgical and postsurgical. The four most important presurgical traps are:1. Absence of treatment plan, when orthodontist and surgeon do not communicate. This scenario looks like a stray ship in the sea. The results may be randomly good if the teeth appear well aligned and symmetrically positioned within the jaw bones. Also, this kind of random orthodontic setup may lead to a dead end, if the surgeon sees that the teeth have been camouflaged and that dental midlines do not coincide with the skeletal midlines; molar torque is different on both sides; dental cants do not match with the skeletal cants (different dentoalveolar heights between the sides) or if there is an obvious dental compensation instead of decompensation. In all the above-mentioned scenarios, facial planning is aggravated since the position of the teeth may influence the vector and repositioning of jawbones too much.
2. Instabilities in orthodontic treatment: expansion of dental arch, orthodontic leveling of dual occlusal planes, which may lead to loss of occlusion after treatment. In non-surgical cases, the relapse is not so heart-breaking as in surgical cases, for which the patient has already paid a huge physiological cost. Failure to remove hazardous functional components such as tongue thrust, bruxism or mouth breathing may also result in postsurgical relapse.
3. Inadequate attention to the management of the condyles: the stability of occlusion depends half on the occlusion itself and half on the condyles. Healthy large condyles undergo minimal remodeling after surgery and maintain stable occlusion throughout postoperative follow-up. However, diseased condyles that had been affected by arthritis, trauma or overloading as well as systemic medical conditions are subject to major remodeling with loss of volume and occlusal shift throughout the first 18 months of postsurgical follow-up. It is imperative not to put the patient through surgery until the condyles are not stabilized and unloaded with splints and until a smooth condylar surface is seen in the CT or MRI (magnetic resonance imaging) with the absence of inflammatory process.
4. Closure of extraction spaces: in severe crowding or when there is a necessity to decompensate and retract the front group of teeth, premolar extractions are a better alternative than staging surgery with SARPE. However, closure of extraction spaces should be neither random nor forced: application of power chain elastics usually ends up with loss of torque of the front teeth, over-retraction of the front teeth and roller coaster phenomenon. Proper orthodontic techniques need to be utilized to achieve controlled bodily movement of the front group of teeth to achieve the pre-planned position in the alveolar bone and only then the residual extraction space should be closed by protraction of the back teeth.
The most important surgery-related traps are:1. Poor facial planning: occlusion-driven facial planning will result in frustration if facial harmony is worsened or new facial deformities appear. One of the most challenging and important steps of the workflow is the aesthetic facial treatment planning in the profile and front views, since the highest motivational factor for patients seeking orthognathic treatment is improvement of facial aesthetics.
2. Improper surgical technique resulting in malocclusion or misplaced correct occlusion: unfavorable splits of the jaws leading to inadequate mobilization; failure to remove bone collision points, leading to improper seating of the condyles; improper technique for seating the condyles in the glenoid fossa; non-passive plating of the osteotomy lines; failure to stabilize buttresses with bone grafts.
3. Insufficient follow-up after surgery by the surgeon: occlusal slides may lead to loss of midline and may affect the healing of the osteotomy sites. Therefore, it is important that the surgeon checks for occlusal contacts and adjust the occlusion if necessary by means of negative/positive coronoplasty and/or elastics. The protocol for postoperative care is follow-up visits at days 2, 4, 7, 10 and 14 after surgery, then every week up to 8 weeks, every 2 weeks up to 4 months, every month up to 8 months, then at 12, 18, 24, 36, 48, 60 and 120 months.
The most important postsurgical traps: 1. Restart of orthodontic treatment on both arches at once: after segmental bimaxillary osteotomies the upper jaw segments change vertical height and torque. Therefore, the front 6 or 8 or even 10 brackets need to be rebonded in a passive line or the archwire needs to be bent according to the new position and torque of front teeth. In either way, the change to continuous archwire needs to be smooth. Due to regional acceleratory phenomenon teeth move faster in the alveolar bone. Therefore, it is easy to lose current occlusion if the changes in the shape of the archwire are too big or too fast, especially if both archwires are changed at the same time.
2. Causing temporomandibular disorder (TMD) in the active postoperative phase: too many elastics after surgery used for settling may cause overloading of the condyles and pain, and in rare cases disk dislocation may appear. It is important to have good posterior occlusal contacts if heavy vertical elastics are used for settling. TMD can be caused by closing of spaces in the anterior upper dentition. Retroclination may cause primary contact on anterior teeth and a loss of posterior contact, resulting in occlusal instability and temporomandibular joint (TMJ) pain.
3. Fixed retention does not guarantee stable occlusion after debonding: it is important to put upper and lower teeth in retention by securing back teeth too. Failure to retain the back teeth may result in dental rotations leading to loss of molar overbite and relapse into a crossbite, and formation of the anterior open bite. The most standard type of retention devices we use are: fixed retainers for the front teeth and wraparound retainers with no occlusal interferences for full arch retention. Removable retention devices should be used night time only. Occlusal and dental rehabilitation by creating good cusp to fissure contacts and occlusal guidance is the best retention measure for the long term success.
