TO THE TREATING DOCTOR
The following appliance explanation is being given at the specific request of the doctor treating the case and is not to be viewed as a treatment plan or diagnosis for the patient. Suggestions are based on records furnished, laboratory work performed and are a recap of discussions with the doctor and do not take into account all diagnostic considerations or any treatment considerations that the doctor may exercise. Any diagnosis or treatment of this patient is solely the responsibility of the doctor treating the patient. These explanations are for the information of the treating dentist only. The explanations provided are not to be considered as any attempt to influence or otherwise interfere with the doctor’s independent professional judgment regarding the diagnosis or treatment of this patient, which is the ultimate responsibility of the treating doctor.
Regarding: Case Example (age 12 years)
Concerns for this case according to the cephalometric X-ray and the study models may include:
Profile Angle: The upper lip is 0.8mm in front of the S line giving you a nice upper lip soft tissue profile. The lower lip is 1.3mm in front of the S line giving you a nice lower lip soft tissue profile
SNA: (Position of the maxilla as it relates to Nasion) 81.0°, indicating the maxilla is in an ideal position, (should be 82° +/-2)
SNB: (Position of the mandible as it relates to Nasion) 80.0°, indicating the mandible in an ideal position, (should be 80° +/-2)
ANB: (MX to MD (+)II, (-)III) 1.0°, which is a Class I maxilla to mandible relationship, (should be 2.0° +/-2)
Wits: (Mandible to maxilla according to the occlusal plane) -2.1mm, which is heading towards Class III. (Ideal is 0mm)
Maxilla Length: 81.5mm, which is slightly small
Mandible Length (Modified Harvold Analysis): 108.7mm, which is small
Maxilla to Mandible Difference (Modified Harvold Analysis): 27.2mm, which is Class I
Upper Facial Height (N to ANS): 54.0mm, which is normal
Lower Facial Height is 56.4mm, which deviates from the norm for their age by -5.6mm deviation. This patient is skeletally deep. (Norms are = +/- 1mm)
Upper Gonial Angle is 50.7° (should be 50-55°) and Lower Gonial Angle is 75.6° (should be 70-75°)
NSGoM: 31.6°, neutral grower
Upper incisors are protrusive at 113.0° (should be 102° +/-3); lower incisors are normal at 91.7° (should be 95° +/-5).
The length of the upper incisor (Upper incisor to ANS) is 22.8mm, which is short. (Mean value is 30mm)
Summary: Wits measurement shows mandible in front of the maxilla by 2.1mm which is slight Class III according to the occlusal plane, maxillary mandibular difference shows mandible is large compared to the maxilla by 2.8mm, slight Class III according to size; lower facial height short by 5.6mm, upper facial height balanced, deep skeletal vertical; predominant direction of growth is slight vertical grower due to the steep lower Gonial angle of 75.6°, upper Gonial angle within the norm, NSGoM shows balanced neutral – overall breakdown is balanced neutral with a slight vertical tendency; upper incisors protrusive at 113°, lower incisors retrusive at 91.7°; upper incisor length is short at 22.8mm; mid and posterior airway is slightly constricted.
Schwarz Korkhaus measurements:
UprRt Central 9mm UprRt Lateral 8mm Upper 4×4 -1mm Lower 4×4 -2mm
UprLt Central 9mm UprLt Lateral 8mm Upper 6×6 -1mm Lower 6×6 -4mm
Study cast: Class I molar right and left; Class I cuspid right and left; dental and skeletal midlines appear to be on.
Possible Appliance Suggestions: Possible anterior sagittal, straight into bands and brackets, probable incisor blocks to open the vertical.
Possible Appliance Therapy: Check the airway before proceeding. Once airway has been cleared or diagnosed clear, start the case. Double check for Class III in the family history. If there is a strong Class III in the family history, it is a good idea to place an upper sagittal to move the premaxilla forward about 3mm in conjunction with straight wire. You may have to do some re-contouring of the lower second bicuspids and lower left first bi to help make ideal space; they are mal-shaped and rotated. The lower left is rotated, the lower right is not rotated. Use an .014 thermal to start; do that in conjunction with the upper sagittal if you chose to do the sagittal. Wire sequencing will be: .014 thermal, .018 thermal, to an .019 x .025 multi-modulus for 4-6 months working on getting the lower bi’s rounded out waiting for the second molars to come in. Then place an upper 3×3 extrusion wire and extrude upper incisors at least 2-3mm so that you can open the vertical. When you open the vertical, it will de-rotate the mandible back slightly. If you chose the sagittal, it will be 2-3 months of sagittal development and 3 months of retention. Remember, when you go to the .019 x .025 multi-modulus, place arch wire locks mesial to the molars to hold the sagittal development, and then do extrusion. Take an .017 x .025 extrusion wire and place in the molar brackets. Place an .018 stainless steel sectional wire from canine to canine. The wire will step down and sit passively below the lower CEJ. Flex up above the gingival tie wings and tie to the .018 stainless steel sectional between #8 and #9 and distal to #8 and #9 to start to extrude upper incisors. Then place incisor blocks and second molar buildups and begin verticalization. On the upper arch, stay in the .019 x .025 multi-modulus, place an .014 thermal on the lower and use triangulated elastics to verticalize: upper first molar, upper second bi to lower first molar; upper second bi, upper first bi to lower second bi; upper first bi, upper canine to lower first bi, bilaterally. Place separators between the molars and bi’s for 1 week and have the patient remove with tweezers. Repeat this process as often as the patient can tolerate to speed up verticalization. Once you get first molar contact, remove second molar composite, move to an .018 thermal with vertical elastics to the seconds, and finish with an .019 x .025 multi-modulus. Move the upper to an .019 x .025 CNA at any time during the verticalization process. After case is completed, you can reduce the size of the incisor blocks, but leave incisor blocks for at least 6 months to stabilize the verticalization. Overall treatment time will be about 1 year if you decide not to extrude and open the bite. If you decide to open the bite and extrude upper incisors, add about 6-8 months to the treatment time. Once the case is completed, retain with Hawley retainers.
All supplies mentioned in treatment recommendations can be supplied by Five Star Orthodontic’s supply department. Please go to www.fivestarortho.com for our online catalog and excellent pricing.
All explanations and observations are given solely at the request of and based solely upon the information provided by the treating doctor. Any diagnosis and treatment should be based on the treating doctor’s independent professional judgment without regard to the foregoing explanation or observations.