I was looking for a star — I found the galaxy
Dr. Chris H. Chang
15 years ago, at a time when I spent as much time on a golf course as I did in my practice, a friend suggested that I start a study group of about 20 local doctors to share how and why I was using miniscrews for my treatments. Having started this group, we explored and discussed not only the successes, but also the failures I had encountered, and I made a lot of friends that I wouldn’t have made if I had spent all my free-time on the gold course. Over the years, this group, my circle of friends, and the golf courses I have played on have increased exponentially, based not only in Taiwan, but globally.
Non-Extraction Treatment for Class II Open Bite Using the Combination of Aligners and IZC Screws
Yulin Hsu, Chris H. Chang, W. Eugene Roberts
A 25-year-old male presented with a Class II open bite malocclusion with a lower midline shift to the left. The treatment plan was aligner therapy, with two IZC screws for anchorage. The mechanical advantages of aligners can enlarge the TMJ space by increasing the vertical dimension. A spongy device, aligner Chewies, was used to facilitate the counterclockwise rotation of the mandible, which successfully resolved the open bite. Incisor extrusion, a side effect of retracting the upper dentition with IZC screws, was beneficial for opening the bite. (J Digital Orthod 2021;63:4-16)
Key words: Invisalign®, aligner treatment, open bite, IZC screw
Invisalign® Treatment for Bimaxillary Protrusion
Chao Pan, Sophia Shu, Chris H. Chang, W. Eugene Roberts
Clear aligners have been increasingly utilised by orthodontists in recent years; however, there are some limitations when treating complex malocclusions and extraction cases with this approach. When clear aligners are the exclusive treatment method, it can be difficult to achieve (1) space closure for four extracted premolars, (2) proper inclination of anterior teeth, and (3) adequate posterior anchorage. The Invisalign G6 solution with mini-screw anchorage has created more options for predictable tooth movement across a wider range of malocclusion types. A 24-year-old female presented with chief complaints of protrusion and crowding of the dentition. Treatment involved extraction of four first premolars followed by aligner treatment using two miniscrews for anchorage. The malocclusion was corrected with no adverse effects, and a normal occlusion was achieved. The patient was extremely satisfied with the treatment results. (J Digital Orthod 2021;63:20-36)
Key words: Bimaxillary protrusion, premolar extraction, clear aligner treatment, Invisalign aligners, Invisalign G6, mini-screws, space closure, anchorage control, torque control
Aligner Treatment for Class III Malocclusion with Anterior Crossbite
Bear Chen, Chris H. Chang, W. Eugene Roberts
Introduction: A 19-year-old male came for consultation for a protrusive mandible and an unesthetic smile. He was previously advised against his preference for clear aligner therapy by other orthodontists.
Diagnosis & Etiology: His facial profile was concave, and the cephalometric analysis indicated a skeletal Class III relationship (ANB -2°). The diagnosis was a skeletal Class III malocclusion with an anterior crossbite and an overjet of -2mm. No functional shift was noted. The molar relationships were end-on Class III bilaterally.
Treatment: The treatment plan was to retract the lower arch with aligners. Class III intermaxillary elastics were added to increase anchorage. Occlusal attachments were installed on the LL6 and LR6 to correct the anterior crossbite. In the 9th month, the anterior crossbite was resolved. The patient finished his first set of aligners in the 14th month. A refinement phase was then initiated to improve the final occlusal outcome.
Results: The total treatment time was 19 months. Overall, the case, with a Discrepancy Index (DI) of 11, was treated to a Cast-Radiograph Evaluation (CRE) of 6 and a Pink & White esthetic score of 2. (J Digital Orthod 2021;63:42-56)
Key words: Aligner, Class III malocclusion, anterior crossbite, Class III intermaxillary elastics, occlusal attachment
Non-Surgical and Non-Extraction Orthodontic Treatment for Severe Skeletal Class III Malocclusion with Negative Overjet
Nawal J. Almutawa, Chris H. Chang, W. Eugene Roberts
History: A 30-year-old male presented for orthodontic consultation with a severe Class III malocclusion, negative overjet, and decreased facial height. The chief complaints were poor masticatory function and compromised dento-facial esthetics.
Diagnosis & Etiology: A decreased vertical dimension of occlusion (VDO) was associated with a deep underbite (-7mm), a generalized lingual crossbite on both sides, a deviated mandibular dental midline (1.5mm to the left), and a skeletal Class lll malocclusion (ANB -5.5 ̊). The probable etiology for the anterior crossbite was functional displacement of the mandible, which led to over-eruption of lower anterior teeth, and developed into a generalized crossbite. The patient was a good candidate for a non-surgical treatment because the facial profile was almost straight with protrusive lower lip despite the reduced VDO which was due to the underbite.
Treatment: A non-surgical, non-extraction orthodontic approach with temporary skeletal anchorage devices (TSADs) was planned. A full fixed appliance was bonded on all permanent teeth in both arches. The anterior crossbite and the VDO were corrected by bonding bite turbos, firstly on the lower premolars and later on the lower anterior teeth, so the profile and the facial height of the patient were improved from the beginning, which led to increased patient confidence and cooperation. Early light Class III elastics were introduced from the early stage of treatment, and different patterns of elastics were used during treatment to facilitate palatal expansion in transverse and sagittal planes. Two TSADs were inserted in the buccal shelves to facilitate the A-P plane correction of Class III. The treatment duration was 24 months when all fixed appliances were removed. Retention was with lower and upper fixed 3-3 lingual retainers, and clear overlay retainers on both arches.
Outcomes: Following a very conservative orthodontic treatment plan of 24 months this severe Class III malocclusion, with a Discrepancy Index of 72 points, was treated to a Cast-Radiograph Evaluation score of 12 points and a Pink and White esthetic score of 3 points. Both the patient and the clinician were very pleased with the treatment outcome. (J Digital Orthod 2021;63:60-74)
Key words: Skeletal Class lll malocclusion, Class lll molar relationship, curve of Spee, VDO, crossbite, TSADs, Bite turbos, Class lll elastics, early light elastics
A Biographical Portrait of Edward Hartley Angle, the First Specialist in Orthodontics, Part 1
Dr. Sheldon Peck
Much of what is known about Edward Hartley Angle, MD, DDS (1855–1930), the acknowledged “father” of modern orthodontics, has been derived from secondary sources, accounts written by his contemporaries and others. New historical research using primary sources, largely the recently published four-volume sourcebook of Angle’s correspondence and business transactions from 1899 to 1910, gives a broad view of the personality, interests, and activities of this prime mover in the evolution of orthodontics. This three- part article highlights aspects of Edward H. Angle’s life and persona, based on new findings culled from his letters and other personal documents. Part 3 presents a biographical chronology of Angle’s remarkable life. (Reprinted from News & Trends in Orthodontics 2009;16:8-14, originally reprinted with permission from Angle Orthod 2009;79:1021-1027. Copyright 2009).(J Digital Orthod 2021;63:78-88)
Taiwanese Lifestyle Trough the Eyes of CC
Wildlife Habitat for Quail
“Ideas lose themselves as quickly as quail, and one must wing them the minute they rise out of the grass, or they are gone.” — Thomas F. Kennedy.
This quote by Thomas F. Kennedy (1858-1917) vividly portraits the nature of quail - easily alerted and quick to run into hiding. The word quail is even used as a verb, meaning to feel or show fear, or to want to move away from something out of fear (source: Cambridge online dictionary).
Quail are mid-sized, ground-dwelling birds, with the term covering a wide variety of breeds and species; the most common quail in Taiwan and most East Asian countries is the Japanese quad. An adult quail on average weighs around 10oz (≈ 130g, with females slightly heavier than males) and measures around 20cm in length. Chicks mature after about 6 weeks and a female adult quail can lay up to 300 eggs in a year, a profitable and abundant resource for farmers and scientific research.