Dr. Chris H. Chang
Since time immemorial, human has always been looking for the simplest way to deal with their problems. Sometimes, a simple solution can be found with very little effort, sometimes by chance, but sometimes, we really have to rack our brains for it.
Steven Jobs had his 3 levels of pro philosophy: simple solutions from simple thinking, complex solutions from deep thinking, and simple solutions from insanely deep thinking. It is the last level which we follow in our case reports for this journal, finding a simple solution to our complex cases by giving them a tremendous amount of thought! As we explore new horizons with newly developing mechanics, it is of utmost importance that we use them in the simplest manner possible…
Simple Solution for Brodie Bite with Skeletal Class II Asymmetry
Bear Chen, Chris H. Chang, W. Eugene Roberts
Introduction: A 30-year-old female presented with a chief complaint of difficulties in chewing due to a constricted lower arch and a unilateral full buccal crossbite (scissor-bite or Brodie bite). She requested a non-surgical treatment, but agreed to extra-radicular temporary anchorage devices and any required extraction of teeth.
Diagnosis & Eitiology: Her facial profile was convex with protrusive lips. Lip incompetence was not obvious. Skeletally, the mandible was retrusive (SNB 75º) with an ANB of 7º, indicating skeletal Class II. There was 7mm crowding in the upper arch and none in the lower arch. The buccal crossbite on the left side, as well as asymmetrical condylar heads and mandible, resulted in a 5mm deviation of the mandible to the right.
Treatment: A non-surgical approach was indicated using passive self-ligating brackets. Glass ionomer bite turbos (BTs) were bonded on the occlusal surfaces of the lower right molars at the beginning of the treatment. The extra-radicular temporary anchorage device (E-R TAD) that was indicated was a 2x12-mm OrthoBoneScrew® (OBS), which was inserted in the left mandibular buccal shelf (MBS). Elastomeric chains, anchored by the OBS, extended to lingual buttons bonded on the lingually inclined lower left molars. Cross elastics were added as secondary up-righting mechanics. The lower right BTs were removed in the third month when the posterior crossbite was corrected. In the nineteenth month, BTs were bonded on the lingual surfaces of the upper central incisors, and an OBS was inserted in each infrazygomatic crest (IZC) and pre-maxillary area. The Class II relationship was resolved with retraction of the maxillary arch using IZC anchorage and intermaxillary elastics. The gummy smile was corrected by intruding the upper anterior teeth with pre-maxillary anchorage.
Results: The scissor-bite and lingually inclined lower left posterior segment were sufficiently corrected after 3 months of treatment. The anterior BTs opened space to extrude the posterior teeth and level the lower arch, and the IZC and pre-maxillary bone screws anchored the retraction of the maxillary arch. In twenty-seven months, this difficult malocclusion, with a Discrepancy Index of 29, was treated to a Cast-Radiograph Evaluation of 12 and a Pink & White esthetic score of 3. (J Digital Orthod 2021;62:4-23)
Key words: Scissor-bite, Brodie bite, buccal crossbite, lingually inclined lower molars, maxillary protrusion, lip protrusion, cross elastics, occlusal bite turbo, extra-alveolar anchorage, mandibular buccal shelf, mandibular rotation, infra-zygomatic crest, inter-proximal reduction, bone screws, TADs
Combining Orthodontics with an Implant-Supported Prosthesis to Replace Multiple Congenitally Missing Maxillary Teeth
Yen-Feng Lee, Chris H. Chang, W. Eugene Roberts
History: Congenitally missing maxillary lateral incisors are the second most common dental agenesis, exceeding only by third molars. The congenital absence of one or more maxillary lateral incisors usually compromises the esthetics and may also be associated with dental midline as well as functional occlusion problems.
Diagnosis: A 21-year-1-month-old male presented with a chief complaint (CC) of an unattractive smile due to irregular teeth and spacing. The UR5, UL2, UL4, UL5 were all missing. The upper left lateral deciduous incisor was retained, but there were several edentulous spaces in the maxillary arch. A clinical examination revealed a Class I molar relationship on the right side, end-on Class III molar relationship on the left side, lingually tipped incisors (U1-SN 96˚, L1-MP 76˚), an upper left lateral deciduous incisor (ULb) in crossbite, as well as spaces mesial and distal to it. The discrepancy index (DI) was 21.
Treatment: The dentition had to be aligned while maintaining enough space for an implant-supported prosthesis (ISP) to restore the upper left incisor (UL2). The cusp height of ULe had to be reduced to let the gingiva grow over it and regain space for a crown and bridge prosthesis to restore the UR5, UL4, and UL5. The pre-prosthetic orthodontic treatment duration was 18 months. In the 16th month, the ULb was extracted and the UL2 area implant was placed simultaneously. Soft tissue was formed with a healing abutment associated with simultaneous guided bone regeneration around the implant. After a 6-month healing phase, the prosthetic abutment was placed and adjusted to achieve 2mm of interocclusal clearance. The final crown was delivered 2 weeks later.
Results: The dentition was aligned, and all spaces were closed except for the UR5, UL2, UL4, and UL5 edentulous sites. Following the completion of the ISP to restore the UL2 and a bridge prosthesis to restore the UR5, UL4, and UL5, the overall treatment was excellent, as evidenced by a Cast Radiograph Evaluation (CRE) score of 15, and Pink and White (P&W) dental esthetic score of 6. (J Digital Orthod 2021;62:28-45)
Key words: Congenitally missing, implant placement, 2B-3D rule, bone augmentation
Anterior Crossbite Treated with Four-Bicuspids Extraction and Insignia® System without Manual Adjustments or TADs
Connie Huang, Chris H. Huang, W. Eugene Roberts
An 18-year-old girl reported with chief complaints of crooked teeth, prominent chin, and depression of mouth corners. She was diagnosed with a unilateral end-on Class III (Super Class I) with anterior crossbite, and severe crowding (20mm) in the upper arch. The orthodontic treatment was accomplished in 19 months with extraction of the four first premolars and the application of a custom-made self-ligating orthodontic appliance, Insignia® (Ormco, Brea, CA). There was no bracket repositioning, nor archwire adjustments. At the one-year and two-year follow-up, the improved functional occlusion and esthetics were stable. (J Digital Orthod 2021;62:52-70)
Key words: Insignia® system, customized passive self-ligating bracket, digital set-up, bite turbos, anterior crossbite
Efficient Correction of Crowded Anterior Crossbite: Passive Self-Ligating Brackets and Anterior Bite Turbos
Chia-Wei Liu, Chris H. Huang, W. Eugene Roberts
Etiology: A 16-year-5-month-old female presented with chief complaints of anterior crossbite and crowding. Past medical history was non-contributory, but dental history revealed that the upper left second premolar was extracted because of a blocked-in position.
Diagnosis: Extra-oral examination revealed a symmetric, but long tapered face in the frontal view, with a SN-MP angle of 39˚. The facial profile was convex with competent lips, and the lower lip was protrusive. There was an asymmetric Class III (right) and Class II (left) molar relationship, anterior crossbite, intermaxillary crowding, and a missing upper left (UL) second premolar. The Discrepancy Index (DI) was 27.
Treatment: This challenging malocclusion was efficiently corrected with a passive self-ligating fixed appliance, anterior bite turbos, progressive archwires, and intermaxillary elastics. After only 16 months of active treatment, the patient was satisfied with the result, and requested appliance removal prior to the planned completion of treatment.
Results: Lip profile was improved, and there was no lip strain when the patient smiled naturally. After 16 months of active treatment, the dental outcomes were acceptable, with a Cast Radiograph Evaluation (CRE) score of 24 and a Pink & White dental esthetic score of 7, but the result could have been improved with more detailed finishing. (J Digital Orthod 2021;62:74-90)
Key words: Anterior cross bite, extraction, asymmetric Class II and III, passive self-ligating appliance, crowding
Taiwanese Lifestyle Through the Eyes of CC
Chapter 1. Eco-Pond Filtration System
During the ongoing global pandemic, Dr. Chris Chang has had the opportunity to stay in Taiwan and complete his ideal home for his future retirement. Attempting not only to create a haven for his family, but also to accommodate Taiwanese wildlife, he turned to the US National Wildlife Federation for their guidance in creating a wildlife habitat. In order to be recognized as a Certified Wildlife Habitat, a property has to be able to sustainably provide essential elements such as food, water, cover, and places to raise young. Among these essentials, water is of the greatest importance to life - not only how it maintains life, but also in the creation thereof…