Monday, April 27, 2015

Correction of an Impacted and Severely Displaced Central Incisor in an 8 Year Old Patient

This patient (8 years old) presented to our practice after referral from their dentist after it was discovered that his upper left central incisor was displaced severely and would not erupt due to the presence of two supernumerary teeth (extra teeth) in the same region.

The initial panoramic radiograph shows the central incisor crown tipped up toward the nose and one of the developing supernumerary teeth is circled. The other had already been removed previously. Supernumerary incisors in the maxilla (upper jaw) are actually fairly common and are called mesiodens if in the region of the central incisors.

The initial cephalometric radiograph cleary shows just how far the extra tooth's development pushed the central incisor out of position.

To correct this problem and bring the impacted central incisor into position, we placed limited braces along with a transpalatal arch bar and referred him to an oral surgeon to attach a button and gold chain to the impacted incisor. The button and chain allow the orthodontist to gradually guide the tooth in by applying orthodontic traction in desired directions periodically. The surgeon determined that the extra tooth was too close to the incisor needing to be moved so he wanted to perform a second surgery later to remove the extra tooth once there would be minimal risk of damage to adjacent teeth.

The following photo is following the surgery with our orthodontic appliances in place:

We started seeing him once per month to apply orthodontic traction with an elastic thread usually and gradually bring the tooth in. The discomfort associated with activation is usually minimal and lasts for just a few minutes. The patient did great at every appointment.

This panoramic radiograph shows the attachment of the gold chain to the lingual (backside of the tooth):

The next progress panoramic radiograph shows the position of the central incisor after 6 months of activation. The supernumerary tooth is much more visible also, so it was decided that it was time for a second visit to the oral surgeon to now remove the extra tooth safely now that the central was not so close and move the button from the underside of the tooth to the more ideal position on the front side of the tooth:

Here is the tooth 10 months after starting traction with the button now on the facial but still a lot of root movement needed to get the tooth into the right angulation:

And finally here is the final photo and panoramic radiograph. The central incisor has good root form and is fully vital making the case a great success. We are currently giving him a little break and will start his comprehensive orthodontic treatment with full braces once the rest of his permanent teeth finish erupting to ideally align all teeth, even the vertical position of the central incisors a little better and perfect his bite. Needless to say he was very excited to have that front tooth finally!

Tuesday, April 22, 2014

Impressive Orthognathic Surgery Correction of a Patient With a Pituitary Tumor

Pituitary tumors can cause widespread effects on our bodies because the pituitary gland secretes a total of nine hormones and is vital for homeostasis. Human growth hormone (HGH) is often one of the hormones that starts to increase when a tumor of the pituitary gland is present and the increased production of HGH can lead to dramatic changes in the body, even in adults.

When excess HGH is being produced in the body, a condition known as acromegaly results. Acromegaly causes soft tissue swelling, pronounced brow protrusion, pronounced lower jaw protrusion (prognathism), macroglossia (enlargement of the tongue), and related shifting of teeth.

The following patient presented to Avery Orthodontics after referral from the Oral Surgery Department at the University of Texas Health Science Center San Antonio. She was 28 years old and had a benign pituitary tumor removed about 6 months earlier. The goal of the surgery department was to repair the effects that the acromegaly had, namely macroglossia and prognathism (protrusion of the lower jaw). As you can see in the initial photos below, the effects of the tumor on the bite and jaw structures was dramatic:

My job as the orthodontist was to align the teeth, close excess spacing and level the arches so that the surgical team could then have an upper arch and a lower arch that matched nicely when they move the underlying jaw bones during the surgery. Full upper and lower braces were placed and in a little over a year, she was ready for her surgery. Her hormone levels were continuously checked after the removal of the tumor as we would not have wanted to perform the jaw surgery until we were certain that hormone levels were normal and stable again.

The following photo shows our progress prior to surgery:

Dr. Daniel Perez (Department of Oral Surgery, University of Texas Health Science Center San Antonio) and his surgical team were tasked with quite a challenge as the distance of the surgical moves in this case were larger than usual. The summarized surgical plan was to set the mandible (lower jaw) back while also attempting to correct the asymmetry present with a little more of a set back on the right than the left sides. The maxilla (upper jaw) meanwhile would need to be widened and brought forward the necessary distance to end up with the teeth in the proper bite position while trying to improve facial balance and esthetics as much as possible. Finally, the tongue would need to be reduced (glossectomy) due to the macroglossia that had occurred.

The resulting surgery was one of the finest orthognathic surgeries I have ever seen performed. When the patient returned to us, it was a simple matter to finish out the detailing of her bite and putting the teeth into their final positions. The post-surgical phase of orthodontics usually takes from 6-12 months and is shorter if the bite is already in great position following surgery, requiring less detailing on the orthodontist's part. It is with great admiration for Dr. Perez and his team in San Antonio that I present the final photos. As you can see, we have an almost ideal bite at the finish. I did not include facial photos for patient privacy, but needless to say the improvement in facial symmetry and balance were also dramatic. The missing lower molars are planned to be replaced with either bridges or dental implants in the future. She will always be one of my favorite patients due to the way she bravely handled all the difficult medical challenges she faced and I cannot be prouder that we were able to erase the effects of the pituitary tumor and get her confident and smiling once again.

Tuesday, April 23, 2013

Case of the Month: April 2013 (Orthognathic Surgical Correction)

This month's case illustrates the sometimes life changing transformation that orthodontics combined with orthognathic (jaw) surgery can make.  This particular patient presented to our office at age 15 wanting straighter teeth, an improved bite and an increase in the prominence of her lower jaw.

She was diagnosed as having a constricted maxilla (upper jaw), retrusive mandible (lower jaw) in part to a high jaw angle, proclined and protrusive upper incisors (front teeth), and an excessive overjet (front to back distance between the upper and lower incisors).  Her facial balance needed improvement due to the lower jaw being so retrusive, which also causes the lip balance to appear strained when trying to keep the lips closed.

The initial cephalometric radiograph below illustrates the jaw and bite discrepancies from a lateral view (patients facial photos are not shown for privacy purposes):

During our orthodontic consult, we explained that jaw surgery would be required to meet all of the patient's goals and expectations due to the severity of the skeletal discrepancies.  Many cases with more mild skeletal problems can be fixed with orthodontics alone, but some cases require the jaw bones themselves be moved to create the proper balance.  A referral was made to Dr. Steve Widner, an oral surgeon in central Austin.  After discussing the patient's case, Dr. Widner and I agreed that two-jaw surgery involving expanding the upper jaw along with tipping the back part of the upper jaw up and an advancement of the lower jaw would meet everyone's expectations.  The upper front teeth would also have space to tip back once the upper jaw was widened surgically.

Orthodontic treatment was initiated with the expected 12 months of pre-surgical tooth movements needed.  Essentially it is the orthodontist's job to align and level each arch individually so that when the jaws themselves are moved, the dental arches and bite will fit together nicely.  Once we were ready and all preparations were made, the jaw surgery was completed and about 9 months of post-surgery orthodontic finishing was done.  Jaw surgery usually requires 2 weeks of rest (usually no school or work) post-surgery and patients start feeling 100% about a month after the surgery.  A month of rest and healing is worth the dramatic quality of life improvement in my opinion.

The following before and after photos impressively illustrate the powerful changes that jaw surgery combined with orthodontics can make for those who can benefit from it:

Believe it or not that is the same patient in the before and after photos and needless to say she is thrilled and can't wait to start college.

Sunday, January 6, 2013

Case of the Month: January 2013

The following case will demonstrate the effectiveness of early orthodontic intervention to address an ectopically erupting tooth (a tooth erupting in the wrong direction or location) followed by the use of pre-molar extractions during comprehensive treatment to alleviate severe crowding.

The patient presented to the office at the age of 9 having been sent by her pediatric dentist due to a mandibular incisor erupting ectopically.

 As you can see above, the lower right lateral incisor erupted backwards in the dental arch, while the primary (baby) incisor (yellow X) that should have been lost was not.  This is obviously a problem because the canine and first pre-molar on that side would be blocked from erupting in the future.  She was sent back to her pediatric dentist to remove the retained primary incisor and limited braces on the front four incisors was initiated to tip the ectopic tooth into the correct position.  Because the patient was in the mixed dentition stage (half primary teeth/half permanent teeth), we call any orthodontic treatment at this time early or interceptive because we are essentially ensuring that a normal eruption process can occur.  Other common early or interceptive treatments include maxillary expansion and various types of headgear if a patient has a large enough jaw growth discrepancy. 

The total treatment time for the interceptive treatment was 7 months and the picture below shows the lower incisors in better position.

We continued to monitor the patient's tooth eruption pattern periodically over the next two years and comprehensive orthodontic treatment (full braces once all permanent teeth are in) was initiated at age 12.  When the patient returned almost ready for her comprehensive treatment, she had severe crowding due to a large tooth size/jaw size discrepancy and the decision was made to extract all of the permanent first pre-molars.  Orthodontists try to not have to extract permanent teeth, but the lower jaw limits our ability to expand because the jaw itself does not expand like the upper jaw because it does not have a growth suture in the midline and we also have to be careful not to push the teeth too far forward when aligning them and cause gingival recession. 

 The panoramic radiograph above shows the crowding issues, especially in the lower jaw where some of the canines and pre-molars don't have enough space to erupt.  A referral to her dentist was made to extract the first pre-molars and she returned in 6 months after the remaining teeth erupted to begin her comprehensive treatment.  The pictures below show how she presented at that time.

We then proceeded to place full braces on both arches.  After aligning and leveling each arch, the remaining extraction space needed to be closed.  The patient did a great job wearing rubber bands for us and otherwise did not need any other kinds of appliances.  The pictures below show the nice finish with excellent alignment, great esthetics and all teeth positioned well within their bony housing for long-term good periodontal health.

The total treatment time for phase II or her comprehensive treatment was 20 months, which is pretty typical for extraction cases.  If you look carefully, you can see that we are missing all of the first pre-molars, but no one would ever be able to tell.  Many people you know may have been effectively treated with extractions by their orthodontist.  As I stated earlier, we only extract when we absolutely have to (about 10% of cases in my practice), but extraction cases can work out very nicely when the proper diagnosis and treatment plan is followed.

Sunday, December 2, 2012

Invisalign Summit 2012 Review: Invisalign G4

I recently had the pleasure of attending the Invisalign Summit, which is held every other year and offers orthodontists and their team members an opportunity for continuing education time along with updating all of us on the current changes and innovations that Invisalign is making to improve their product.  I saw a variety of case presentations where Invisalign was effectively used to treat cases that were complex, and in many cases most orthodontists would not have considered Invisalign as an option.  In addition, I am becoming more and more comfortable with Invisalign as an option for teenagers instead of braces with the Invisalign Teen product.  The biggest news out of the conference was the future implementation of Invisalign G4.  Whenever Invisalign makes an innovation that is big enough to warrant calling it a new generation for the product, they give it a "G" tag and thus this is considered the 4th generation of the product.

Here is a video explaining  the new approaches to some of the tooth movements that have been more difficult to achieve with Invisalign versus braces.

Invisalign G4 should thus allow:

1.  Greater root tip control for upper central incisors and canines
2.  Improved predictability for upper lateral incisors
3.  Better clinical outcomes for anterior open bite treatment

All three of those categories of tooth movement were by far the most unpredictable with Invisalign treatment in the past, so I am looking forward to being able to offer the Invisalign option to patients who have those tooth movement needs to achieve a nice result.

Finally, the news I was most excited about was to hear that Invisalign has been very active in researching ways to improve the properties of the plastic used for the aligners.  Invisalign suffers in comparison to braces in that the force levels are fairly high with the initial placement of the new trays and they then decay over the typical two week period a set of trays is worn.  Not to get too technical, but this is the opposite of the properties of the initial wires we place to start the alignment and leveling process in a braces patient.  The initial wires are made of nitinol and deliver a low, almost constant force throughout the period that they are in the mouth.  These wires were obviously a huge advancement a few decades ago for the profession.  As this chart shows, the plastic they are working on should allow force levels more in line with the most ideal for efficient tooth movement and I feel it could be a major game changer for clear aligner treatment versus braces.



Friday, September 28, 2012

Case of the Month, September 2012

This month's case will illustrate an impressive improvement of a patient's overbite due to the lower jaw being positioned too far back or posterior to the upper jaw.  This is a common problem that orthodontists have to correct and not only does it result in a more functional bite, it can greatly improve lip and facial balance.  There are many methods of correction of these types of bites and this case will demonstrate a non-surgical correction that avoids the use of headgear.

The patient was 12 years old at the start of treatment and the initial photos below illustrate the large overbite (vertical), overjet (front-back discrepancy of the front teeth) and class II occlusion (lower back teeth a full tooth behind where they should be versus the upper teeth).

The cephalometric radiograph shows the poor soft tissue profile and proclined incisor positions.

The method of bite correction used in this case was an appliance called Forsus Springs.  Once the teeth were well aligned and leveled (about 6 months), the Forsus springs were placed and worn for 6 months.  This is a great appliance when methods such as rubber band wear alone would not be expected to achieve desired treatment results and the patient does not desire to wear headgear or other less patient friendly appliances.  Patients actually do quite well with the springs, as they are flexible and allow a wide range of jaw movements, making eating almost normal.  They are also not too large and sit on the sides of the mouth and thus are not highly noticeable.  The force the springs apply is also at at low, constant level, so the discomfort is not a bad as one might think. 

Illustration of the Forsus Springs appliance.  We placed springs on both sides, but they can also be very effective placed on one side when the bite is asymmetrical and off on one side only.  The springs are not removable (probably another reason for their high effectiveness).

The results of our treatment are shown below.  The bite was fully corrected to an ideal overbite and overjet and a marked improvement in lip and facial balance can be seen on the lateral radiograph (actual facial photos of the patient are not shown for patient privacy).  The total treatment time was right at 2 years with a few months added on because we had to wait on a few teeth to finish erupting near the beginning of treatment.  Our young patient did a wonderful job and all in all we are very proud of the finished product.