Case Nh

A 30-year-old male patient with severe anterior crowding on mild Class il dental bases (ANB 5°). He had Class I buccal segments, and third molars had been previously n r-

There was a high-angle pattern (MM angle 35°). Lower arch form was checked with transparent arch form cards, and assessed as approximately ovoid.

The upper right central incisor was recorded at 12 mm to APo line and lower left central incisor at 5mm to APo line. It was decided that the treatment goal would be to retract and align incisors to a planned incisor position (PIP) of approximately 7rnm to APo in the upper and 3 mm to APo in the lower.

Bendbacks were used to ensure that the ends of the archwire were comfortable in the molar area, and to help control mesial movement of the anterior teeth. (Bendbacks and lacebacks are normally continued throughout tooth leveling and aligning, until the rectangular steel archwire stage, in most cases.) Upper and lower ovoid .016 HANT wires were placed. Standard .022 metal brackets were used for optimal control, and bands were placed on all molars and premolars. The instanding lower incisors were not bracketed at this stage, because no space was available to position them in the line of the arch. Rubber sleeve was used for patient comfort meantime.

Treatment mechanics were required to align upper incisors approximately to the starting position of the upper left central incisor, or a little more distally. In the lower arch, the objective was to align the lower incisors to the starting position of the lower right central incisor. It is desirable to treat as many cases as possible without extractions, but in this case there was a need to make space available for lower incisor alignment and retraction. Sufficient space could not be obtained from expansion or from enamel reduction. A decision was therefore made to extract all first premolars, and to treat this high-angle case as a maximum anchorage case, using an upper palatal bar and a lower lingual arch to support tooth movements during leveling and aligning stages.

N.H.Begin 30.4 years 11/4/97

SNA SNB ANB AN FH Po-N FH WITS GoGnSN FM MM 1 to A-Po 1 to A-Po 1 to Max Plane to Mand Plane

-3 mm -15 mm 3 mm 42 0 32 ° 35 0 12 mm 5 mm 115 0 94 0

■ ¿ 'www.allislatn .net » »

N.H.Begin 30.4 years 11/4/97

Fig. 9.45

Occlusal views of the case at the start of treatment. A lower lingual arch and an upper palatal bar were used at the outset of treatment for anchorage control.

Sequential views at early adjustment visits. At the first adjustment visit, the archwires were removed. The lower was checked, and the ends were re-flamed to re-soften them for new bendbacks. Upper and lower lacebacks were slightly tightened, to remove the 1 mm or so of slack which typically develops between adjustments in the early stages of treatment. An upper .019/.025 HANT wire was placed with bendbacks. The ends of the HANT wire were flamed and quenched before placement.

At this stage, the case set-up can be clearly seen. As the upper incisors start to level, a 0.5 mm vertical adjustment to the upper right central incisor bracket can be seen (Fig. 9.52). This tooth was eventually to be restored and the slight extrusion was to facilitate the restorative procedure. Double upper molar tubes were placed to allow headgear support.

Normal canine brackets are in use with -7° upper and -6° lower torque. Consideration could be given to using 0° torque brackets in this type of case to assist in keeping the canine roots in cancellous bone. At subsequent visits, the lower .016 IIANT wire was replaced with a .016 round steel wire and open coil springs to recreate space for lower incisors. Brackets adjacent to the open coil were tied with wire ties to prevent rotations.

The case after 9 months of treatment. Upper lacebacks were discontinued and the upper rectangular 1 IANT wire was replaced with a steel .019/.025 rectangular wire with soldered hooks and passive tiebacks. Enough space had been created for alignment of the instanding lower incisors, and these were bracketed. A lower .016 I IANT ovoid archwire was used with lacebacks and bendbacks to start moving them into the line of the arch. It is not correct to attempt this before enough space has been created, as there is a risk of proclination and then a need for torque correction later.

Sequential views of the right side showing space closure with the Hycon® device. No obstacles to space closure were evident, and alternative mechanics such as tiebacks with two modules, or a looped archwire were considered. A decision was made to use the 1 Iycon® device from Edenta. This has been used successfully by one of the authors for 4 years in selected cases.

Sequential views of the case after 10 months (Fig. 9.56), 13 months (Fig. 9.57), and 18 months (Fig. 9.58).

At the 7-month adjustment visit, a rectangular .019/.025 I1ANT lower wire (ovoid shape) had been placed, and at the 10-month adjustment visit, a rectangular .019/.025 steel lower wire (ovoid shape) was possible, with soldered hooks and passive tiebacks. At this stage, consideration was given to producing an individualized arch form (1AF) for this patient, but it was felt that the normal ovoid form was veiy close to the starting lower arch, and could therefore be used. Normal space closure was carried out with active tiebacks, but difficulty was experienced in closing the upper right premolar space. This is unusual. In almost all treatment of children, the spaces will close uneventfully using sliding mechanics and active tiebacks. In a few adult treatments, it may be found that spaces are slow or difficult to close with the normal mechanics, and there may be a need to use a rectangular wire with space-closing loops or a I Iycon® device.

Sequential occlusal views showing space closure. Approximately 1 mm of space closure can be accomplished per month. This device provides a very short-acting but strong force that essentially overcomes any frictional concerns. If overdone, however, it will lead to significant archwire deflection, which should be avoided. The Hycon® device, like palatal expanders, distraction osteogenesis screws, and some molar distalizing devices, requires diligent patient cooperation to ensure success.

The final settling stage of treatment, after 20 months. Finishing and detailing was not a separate and lengthy stage of mechanics in this case; as a result of good early treatment management, only careful settling was needed before proceeding into retention. A .016 round FIANT wire was used in the lower arch, with ovoid arch form. In the upper arch, a .014 round sectional wire was placed from lateral incisor to lateral incisor. Teeth had been extracted, and therefore figure-8 ligature wires were placed across the extraction sites to hold them closed.

The .014 settling wires were accompanied by the use of light vertical triangular elastics and good settling occurred. In cases with accurate bracket placement, few elastics need to be used in this way. It was decided to keep all bands and brackets on the teeth during settling, so that if unwanted changes occurred, these could be corrected. The patient was seen at approximately 2-week intervals during the settling phase. Elastics were worn full time for the first 2 weeks, then at night for a period of 2 weeks.

The case after appliance removal. A lower bonded retainer was placed from second premolar to second premolar, to stabilize the lower anterior alignment and to prevent premolar space opening. It was recommended that the lower bonded retainer should be left in place indefinitely.

N.H. Begin

N.H.Final

A lower canine-to-canine lingual bonded retainer is placed for almost all the authors' patients at the end of treatment, and in first premolar extraction cases this is normally extended on to the mesial fossae of the second premolars, as in this case. I he multistrand wire may be .015 or .019, and it is bonded with a very careful technique, usingTransbond LR™. An upper vacuum-formed retainer was lilted, after adjustment to the restoration on the upper right central incisor. In the upper arch, the majority of relapse is likely to occur within ihe first 6 months, and the patient was therefore asked to wear the removable retainer full time, or as often as possible for several months.

Some band space is present mesial to upper second molars. This is a recurring problem in adult treatment. During finishing a tube can be bonded on to each second molar after removal of all molar bands. F.lastic chain may be used lo close band space on the rectangular wire, with incisor, canine and premolar teeth still carrying bonded brackets.

SN at S

Fig. 9.73

Palatal Plane & Palate Curvature

Fig. 9.75

Palatal Plane & Palate Curvature

N.H.Begin

N.H.Final

Mand. Symphasis & Mand. Plane

N.H.Begin N.H.Final

N.H. Final

32.9 years 3/28/00

N.H. Final

32.9 years 3/28/00

SNA 78 SNB 73 ANBZ 5 A-N FH -2 Po-N FH -13 WITS 4 GoGnSN 41 FM / 31 MM .'33 1 to A-Po 7 1 to A-Po 3 1 to Max Plane 104 1 to Mand Plane 91

A female first premolar extraction case, aged 11.6 years at the start of treatment, with Class 11 skeletal bases (ANB 7°) on an average angle pattern (MM 28°).

Dentally, there was anterior and posterior crowding with a lack of space for permanent canines. There was upper and lower incisor crowding with rotations. Archform was assessed as ovoid. It was felt that four first premolars should be extracted in order to achieve a stable result with good profile and healthy periodontal tissues.

After first premolar extractions, the first molars were banded, and standard metal brackets were placed in the lower arch. Commencement of upper arch bracketing was delayed until after eruption of the upper second premolars. The initial lower archwire was .016 IIANT, and here the case is seen after 2 months of treatment with .020 round steel wires in place. Lower lacebacks were placed to control and slightly retract the canines.

M.O. Beginning 11.6 years 3/7/97

Fig. 9.81

M.O. Beginning 11.6 years 3/7/97

SNA x 86 0 SNB / 79 ° ANB/ 7° A-N FH 4 mm Po-N FH -5 mm WITS 0 mm GoGnSN 36 ° FM / 27 ° MM 28" 1 to A-Po 7 mm 1 to A-Po 3 mm 1 to Max Plane 111 ° 1 to Mand Plane 94°

A lower lingual arch and an upper palatal bar were placed to support anchorage during the early stages of tooth alignment.

When upper second premolars were close to full eruption, the six upper anterior teeth were bracketed and a .016 HANT wire was placed with passive coil springs to protect the long buccal spans of the archwire. Lower lacebacks were discontinued at this stage, as the canines were beginning to move away from the lateral incisors.

Sequential view of the "right side of the treatment after 7 months, 11 months, and 15 months of treatment. At 7 months, upper and lower rectangular I IANT wires are in place, and the upper canines have retracted a little away from the lateral incisors, as the lower canines have moved distally. This is acceptable during tooth leveling and aligning, and provides a small amount of additional anchorage. Subsequently, upper and lower steel rectangular wires were placed, with light (Mass II elastics during space closure. Passive tiebacks were placed to maintain the space closure.

After 2 years of active treatment, settling was commenced. I lere, the case is seen prior to appliance removal. Light triangular elastics were used in the molar and premolar regions and the patient was checked at 2-weekly intervals.

Fig. 9.93
Fig. 9.101

Fig. 9.103

The case after appliance removal. Active treatment time was slightly extended to 27 months because of delays early in the treatment whilst awaiting the eruption of premolars.

Fig. 9.106

Post-treatment facial profile was pleasing, and the cephalometric measurements were close to normal.

Fig. 9.103

Normal retention, with lower retainers extended onto the lower second premolars. The post-treatment radiographs suggest there is adequate space for eruption of the third molars, and confirm a good relationship between the upper canine roots and upper second premolar roots.

Fig. 9.104

Fig. 9.105

Fig. 9.114

Fig. 9.111

M.O.Begin

M.Q.Finall

Fig. 9.114

Fig. 9.107

Fig. 9.110

Fig. 9.108

SNA Z85 • SNBZ81 " ANBZ 4° A-N FH 2 mm Po-N FH O mm WITS 0 mm GoGnSN 34 0 FM /26 ° MM/28* 1 to A-Po 6 mm 1 to A-Po 3 mm 1 to Max Plane 113 0 1 to Mantl Plane 92 0

Maud. Symphasis & Mand. Plane

Fig. 9.111

Fig. 9.113

Palatal Plane & Palate Curvature

M.O.Begin

M.O.FinaO

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