How Do We Compose Case Reports?
Chris H. Chang
In recent years, a few of our team’s case reports have been published in the world-renowned journal, American Journal of Orthodontics and Dentofacial Orthopedics (AJO-DO). One even received the prestigious 2019 CDABO Case Report of the Year Award. These achievements are the fruits of our labor since 2006, when we started publishing case reports in our own humble JDO. I would like to share our secrets of writing pertinent case reports.
The journey to compose a standard case reports takes only 5 w weeks. In the first week, you need to immerse yourself in the case to firmly grasp as many details as possible. The initial step is to analyze the ceph tracings to understand the change of profile and tooth positions between pre-treatment and posttreatment, followed by studying every treatment step as well as the Discrepancy Index (DI) and Cast-Radiograph Evaluation (CRE) measurements…
Non-Extraction Aligner Treatment for Moderate Crowding and Flared Upper Incisors in a Female with a Flat Facial Profile and Prominent Chin
Yu-Hsin Huang, Chris H. Chang, W. Eugene Roberts
Introduction: A 27-yr-1-mo-old female presented with chief complaints (CC) of flared and crowded incisors. She preferred aligner treatment to avoid oral hygiene problems.
Diagnosis: An assessment of the face revealed slightly concave profile (-2 ̊), increased facial height (54.9%), decreased mandibular plane (FMA, 21°), protrusive maxilla (SNA, 82.0°), protrusive mandible (84.5°), and an intermaxillary discrepancy (-2.5°). Furthermore, there were severely flared incisors (129°) and retroclined lower incisors (77.5°). The dental midline was shifted 2mm to the left, and there was 6mm of crowding in the lower dentition. The Discrepancy Index (DI) was 17.
Etiology: The severe anterior crowding was due to the limited arch development in width.
Treatment: Clear Invisalign® aligners (Align Technology, Inc., San Jose, Calif) were used for the correction of the moderate crowding, flared upper incisors, and retroclined lower incisors. The crowding was mainly relieved by inter-proximal reduction (IPR) and arch expansion. Furthermore, smart-feature attachments were used to improve the rotated teeth. The buccal power ridges were designed for increasing the lingual root torque of the lower anterior teeth. Simultaneous dental movement was employed, and IPR was sequentially performed during the arch expansion and tooth rotation process. During the active treatment of 41 stages, off-tracking occurred on several anterior teeth in the 26th stage, so the remaining stages of aligner treatment were aborted and additional aligners for refinement were constructed. Four sets of additional aligners improved alignment and detailing.
Results: This crowded and canted dentition, with a Discrepancy Index (DI) of 17, was treated in 29 months with an excellent outcome, with a Cast-Radiograph Evaluation (CRE) score of 13 and a Pink and White dental esthetic score of 2. Both arches were well-aligned, and a Class I relationship was achieved. However, after concluding the treatment, slight bilateral posterior open bite still remained and the LL3, LR2 and LR3 still showed minor black triangles.
Conclusions: Crowded end-on Class III dentitions can be treated with IPR and arch expansion to relieve the crowding and allow tilted incisors to be up-righted without further extraction and miniscrew application. (J Digital Orthod 2022;66:4-22)
Key words: nvisalign, aligner treatment, crowding, flared incisors, anterior crossbite, end-on Class III, arch expansion, inter-proximal reduction (IPR)
Non-Extraction Treatment for Excessive Overjet and Deep Bite with Aligners and IZC Screws
Vicky T. Huang, Bear C. Chen, Chris H. Chang, W. Eugene Roberts
Introduction: A 15-year-11-month-old female presented with chief complaints of protrusion and a severe deep bite.
Diagnosis: Cephalometric analysis revealed a skeletal Class I relationship (SNA, 87˚; SNB, 84˚; ANB, 3˚), reduced facial convexity (-10˚), as well as proclined upper and lower incisors. An intraoral assessment revealed canine Class II malocclusion with an 8mm overjet and an impinged deep bite. There were slight generalized spaces in the upper anterior dentition, and the Discrepancy Index (DI) was 35.
Treatment: The treatment plan was a non-extraction treatment using Invisalign® clear aligner therapy anchored with infrazygomatic crest (IZC) bone screws bilaterally. Class II elastics were used during the treatment to correct the relative position between the upper and lower arches. The active treatment time was 25 months with 3 refinements to effectuate the final result.
Results: Improved dentofacial esthetics and a better occlusal function were achieved after treatment. The Cast-Radiograph Evaluation (CRE) was 12, and Pink and White esthetics score was 4. No significant root resorption nor periodontal problems were noted. The patient was well satisfied with the final outcome.
Conclusions: With Chang’s extraction decision table, a feasible treatment plan was completed with a pleasant result. In retrospect, the treatment time could have been decreased by adding virtual anterior bite ramps, which would reduce the bite- block effect. Overcorrection of intrusion for the lower anterior teeth was applied since, along with canine rotation, it is one of the most inaccurate movements in ClinCheck®. Rearranging the sequence of tooth movements by intruding the lower anterior teeth before retracting the upper arch may also improve this issue. (J Digital Orthod 2022;66:28-42)
Key words: Excessive overjet, deep bite, clear aligner treatment, Invisalign®, IZC screws, anchorage
Class II Malocclusion with Severe Crowding and a Protrusive Profile
Shih-Wei Lu, Chris H. Chang, W. Eugene Roberts
A 25-year-old female presented with almost end-to-end Class II buccal segments, severe anterior crowding bilaterally in the right lateral incisor and canine areas, and a protrusive profile. The Discrepancy Index (DI) was 19. All four first premolars were extracted, canines were moved distally to resolve crowding, and the anterior segments were retracted to correct lip protrusion. After initial alignment and leveling, the residual space was closed with elastometric chains, and Class II elastics were applied to correct the sagittal discrepancy. At progress evaluation, it was noted that the crowding, protrusion, and flaring of upper and lower incisors were corrected, but the buccal segments were still Class II, the bite had deepened, and a 1-2mm midline deviation was evident. Extra-alveolar miniscrews were inserted to complete the correction. After a total of 36 months of active treatment, an optimal result was achieved. The final Cast-Radiograph Evaluation (CRE) score was 24, and the Pink and White dental esthetic score was 2. (J Digital Orthod 2022;66:48-75)
Key words: Protrusive profile, four bicuspids extraction, miniscrew, Angle Class II malocclusion, asymmetric crowding
Taiwanese Lifestyle Through the Eyes of CC
Chapter 5. Maximizing Spaces and Resources - Building a Rooftop Putting Green
Have you ever thought about what your dream house would look like? For Dr. Chris Chang, the answer lies in maximizing all available spaces and turning them into something that can be enjoyed. For example, most Taiwanese households have a rooftop deck; however, apart from hosting a water tank, very few people actually make use of them, let alone know how to have fun with them.
When it comes to making the best use of your rooftop space, the single most crucial key (and we cannot emphasize this more in this lifestyle series - see also Chapters 2 and 3 on building a rooftop garden and a rooftop aviary) is waterproofing and drainage. Dr. Chang always says “no over-retention of water means no leaking!”
(不積水，就不漏水!) This is especially true when designing a golf green with artificial turf, as there are no plants to help absorb any excessive moisture in the base structure. Therefore, instead of the regular one layer, two layers of drainage trays (10cm thick in total) were used in addition to coats of waterproofing for extra draining ability and air circulation at the bottom…