4(3)

TRIANGULAR ELASTICS

  • A variation of vertical elastics
    • Worn from two mandibular teeth to one maxillary tooth (or vice versa) on the same side of the mouth, or from archwire hooks.
    • Purpose: Correction of vertical discrepancies such as a localized open bite.
    • Visual Reference: FIGURE 4.29 COURTESY OF DAMON SYSTEM BRACES FROM ORMCO CORPORATION.

CROSSBITE OR THROUGH-THE-BITE ELASTICS

  • Worn from the lingual or palatal tooth surface of one arch to the buccal tooth surface of the opposing arch on the same side of the mouth.
    • Purpose: To correct crossbites.
    • Visual Reference: FIGURE 4.30 COURTESY OF DR. T. CARLYLE.

ELASTIC CONFIGURATIONS

  • All elastic configurations are interarch with the exception of the Class I elastic.
  • Customization: Elastic configuration is tailored to individual patient needs.
    • Example: Two or more elastic types can be worn simultaneously by the patient.
  • Documentation Requirements:
    • Always record in the patient's chart the size, strength, brand name, and classification of intraoral elastics prescribed.
    • Include instructions for wear (hours of wear) in the chart.

ARCHWIRE ACCESSORIES

  • Accessories are attached to the archwire to complement tooth movement and:
    • Facilitate the placement of some power products.
    • Immobilize the archwire.
    • Provide patient comfort.
  • Record Keeping: Placement and removal of all archwire accessories must be documented in the patient record.

HOOKS

  • Small brass or stainless steel hooks used to attach intraoral elastics.
    • Can be inserted in both the mandibular and maxillary arches.
    • Documentation: Record in the patient's chart the number, type, and location of hooks placed.
TYPES OF HOOKS

  1. CRIMPABLE OR SPLIT HOOK

    • Has a split in the body so it can be attached without removing the archwire.
    • Placed by squeezing the slit closed on the archwire using a Howe, Weingart, or crimping plier.
    • Visual Reference: FIGURE 4.31 CRIMPABLE HOOK COURTESY OF DR. T. CARLYLE.

  2. SLIDE-ON HOOK

    • Body resembles a tube; simply slide it onto the archwire before it is placed in the patient's mouth.
    • Visual Reference: FIGURE 4.32 SLIDE ON HOOK COURTESY OF DR. T. CARLYLE.

CRIMPABLE STOP

  • Stops used to immobilize the archwire to prevent it from sliding around the arch.
    • A crimpable stop has a split in the body for attachment without removing the archwire.
    • Positioned on the archwire and squeezed closed with a Howe, Weingart, or crimping plier.
    • Visual Reference: FIGURE 4.33 COURTESY OF DR. T. CARLYLE.

COMFORT TUBING

  • Made from a plastic material with no elastic properties.
    • Features a hollow core to facilitate sliding over an archwire.
    • Provides patient comfort by covering an archwire that may cause tissue irritation, especially in areas with a long span between teeth, such as an edentulous site.
    • Purpose: Minimizes tissue irritation.
    • Visual Reference: FIGURE 4.34 COURTESY OF DR. T. CARLYLE.
PROCEDURE - PLACEMENT AND REMOVAL OF COMFORT TUBING
  • Armamentarium:
    • Ligature cutter
    • Archwire
    • Weingart plier and all armamentarium needed for archwire insertion
    • Millimeter ruler

  1. PREPARATION

    • Measure the length of tubing required by measuring the edentulous area between the bracket tie wings with a flexible millimeter ruler.
    • Cut the desired length of tubing with a ligature cutter.
    • Confirm the tubing size intraorally; trim if necessary.

  2. PLACEMENT

    • Slide the tubing onto the archwire.
    • Insert the archwire with tubing into the bracket and band slots.
    • Secure the archwire in place with ligatures.

  3. REMOVAL

    • Remove ligatures.
    • Remove archwire from the patient's mouth.
    • Slide the tubing off the archwire.

  4. DOCUMENTATION

    • Record in the patient's chart the length of tubing placed and where it was applied.

ELASTOMERIC ROTATION WEDGES

  • Made of synthetic rubber.
  • Function: Helps correct stubborn tooth rotations not correctable by archwires alone.
PROCEDURE - PLACEMENT AND REMOVAL OF ELASTOMERIC ROTATION WEDGE
  • Armamentarium:
    • Schure instrument
    • Weingart plier
    • Hemostat
    • Archwire
    • Ligatures (elastic or steel)
    • Rotation wedges

  1. PREPARATION

    • Predispense the number of rotation wedges required.

  2. PLACEMENT

    • Grasp the thick side of the rotation wedge with the tips of the hemostat and squeeze to close.
    • Place the holes of the rotation wedge on the mesial or distal tie-wings of the bracket (the direction depends on which way the tooth will be rotated).
    • The bulge on the wedge should be placed toward the desired rotation vector.
    • Seat the rotation wedge on the bracket, ensuring tie-wings come through the holes.
    • Use a Weingart plier to insert the archwire in the bracket slots and buccal molar tubes.
    • Secure the rotation wedge by placing an archwire ligature on the tie-wing opposite the rotation wedge.

  3. DOCUMENTATION

    • Record in the patient's chart where the rotation wedge was placed.

  4. REMOVAL

    • Remove ligatures.
    • Remove the archwire with a Weingart plier.
    • Use tips of hemostats to roll the rotation wedge off the bracket tie-wings.

KOBAYASHI TIES

  • Made from round stainless steel ligature wire, measured by gauge of the wire.
    • Most common sizes are .012 and .014 (slightly heavier than plain stainless steel ligatures).
    • Resemble steel ligature ties but are spot-welded on the end to form a hook to support intraoral elastics.
    • Commonly referred to as "Kobi ties."
    • Combined advantages of ligature ties and hooks.
    • May be placed over or under the archwire.
PROCEDURE - PLACEMENT AND REMOVAL OF KOBAYASHI TIES
  • Armamentarium:
    • Schure instrument
    • Hemostat
    • Ligature cutter
    • Kobi tie

  1. PREPARATION

    • Predispense the required number of ties.
    • Engage the archwire in the bracket slot.

  2. PLACEMENT

    • Kobi ties may be placed before or after archwire insertion.
    • Apply the Kobi tie as described for a single steel ligature.
    • Placement consideration includes where the hook of the tie is on the mesial or distal of the bracket, based on elastic placement. The hook of the Kobi tie is positioned on the gingival tie wings.
    • The hook of the tie may be adjusted for elastic placement.

  3. DOCUMENTATION

    • Record in the patient's chart where the Kobi ties were placed.

  4. REMOVAL

    • Remove the Kobi tie similar to the removal of a single steel ligature.

SECTION FIVE: CHECKING APPLIANCE INTEGRITY AND INITIAL TRY-IN OF APPLIANCES

OBJECTIVES

  • State the purpose of performing a "three minute check."
  • List six potential problems encountered during the "three minute check."
  • Describe facebow selection.
  • Explain the procedure to try-in a maxillary Hawley retainer.
  • Explain criteria for assessing pre-cementation fit of mandibular and maxillary holding arch, and maxillary expansion appliance.
  • Explain criteria for assessing fit of a splint at the try-in stage.

CHECKING APPLIANCE INTEGRITY

  • After fitting a patient with braces or appliances, treatment has begun.
  • Regular appointments typically occur every 4 to 10 weeks, depending on individual treatment plans and prescribed archwires and brackets.
  • Before any adjustments, an evaluation of the patient’s overall oral status is essential.
  • The “three minute check” is crucial at the beginning of each appointment to examine the patient's appliances for potential issues.
COMMON APPLIANCE PROBLEMS

  • Loose or missing band(s)

  • Loose or missing bracket(s)

  • Broken, bent, or loose archwires

  • Loose or missing ligatures, or open doors/gates on self-ligating brackets

  • Appliances that impinge upon soft tissue

  • Improperly fitting removable appliances

  • These problems must be addressed before treatment can continue. If extra work is needed, materials and equipment can be prepared to minimize patient chair time.

THREE MINUTE CHECK (TMC)

  • T - Ties and archwires

    • Verify for loose or missing ligature ties.
    • Check integrity of archwire: determine if it is bent, broken, loose, or missing.
    • Ensure distal ends of archwire are not poking the tissue.

  • M - Missing or loose bands and brackets

    • Check for missing bands or brackets.
    • For loose brackets, apply gentle pressure with the Schure instrument on the gingival edge of the bracket; it should not move.
    • Check loose bands by applying gentle pressure on the gingival edge of the buccal attachment; it should not move.

  • C - Condition of tissue and appliances

    • Inquire with the patient about discomfort or signs of any issues.
    • Inspect the patient’s soft tissue for lesions that suggest ill-fitting appliances.
    • Assess the patient’s oral hygiene.
    • Use an explorer tip to check for gaps between tooth and band for potential "washouts of cement" (indicating cement disintegration).
    • Evaluate condition of any removable appliance to ensure it is not bent or broken, and is clean.

  • Clinical Note: Ensure to inform patients of their appliance and oral hygiene condition. Record results of the three minute check in the patient's chart; additional educational instruction may be required.

INITIAL TRY-IN OF APPLIANCES

  • Newly fabricated appliances from the lab are typically mounted on the patient's study cast.
  • All appliances must be disinfected before insertion, and lab-disinfected appliances may be returned wrapped to indicate this.
  • The initial try-in session serves to ensure the appliance is for the correct patient and provides insight into necessary adjustments.
  • Setup: Required pliers, handpieces, and burs should be prepared in advance to facilitate adjustments.
  • Initial try-in performed by an orthodontic auxiliary generally does not include adjustments.

COMMON APPLIANCES AND ASSESSMENT CRITERIA

MAXILLARY HAWLEY
  • Check Engagement: Adams clasps should engage the undercut on the tooth well enough to hold the appliance in place (should create a snapping sound upon seating).
  • Labial Bow: Should be passive, resting without applying pressure on the anterior teeth.
  • Acrylic Quality: Surface should be smooth and of uniform thickness.
  • Adaptation: The appliance should fit well against any soft tissue, especially on the lingual surface of teeth.
MAXILLARY AND MANDIBULAR SPACE MAINTAINER (HOLDING ARCH)
  • Passive Checking: Seat one side to confirm passivity of the opposite band; this must be directly over the tooth, both buccolingually and mesiodistally; any deviation indicates the appliance is not passive and needs adjustment.
  • Sequential Procedure: Repeat for the other side.
  • Lingual Bow: On the mandibular arch, it must sit passively against the cingulum without tissue impingement; the maxillary arch should not impinge on palatal tissue.
PALATAL EXPANSION APPLIANCE
  • Initially passive; activated by the dentist before cementation (for Quad Helix) or after cementation (for Hyrax).
  • Size Consideration: Bands fitted a size larger than usual to facilitate insertion; they should slide on and off the teeth easily without tissue impingement.
VACUUM FORMED RETAINER OR CLEAR RETAINER AND SEQUENTIAL ALIGNERS
  • The appliance should slide onto teeth with finger pressure and should not rock once seated.
  • Tightness: Expect initial tightness lasting a couple of days.
  • Removal: Gently pry off starting at the molars.
  • Cleaning: Instruct patients to clean with a toothbrush and wear as directed; remove to eat.
BONDED LINGUAL RETAINERS
  • Teeth prepared as with bonding a bracket.
  • If bonding six teeth, intraoral elastics are placed around laterals to hold the lingual bar; elastics removed post bonding.
  • If fewer than six teeth are involved, use floss between centrals and laterals to hold the bar during bonding.
  • Maintenance: Ensure cleaning well around bonded wire with toothbrush and floss (a floss threader may be necessary).
  • Key Consideration: Ensure the wire is bonded passively to avoid inducing unwanted tooth movement.
SPLINT
  • Appliance should snap onto the occlusal surface without rocking.
  • Ensure there's no tissue impingement.
HEADGEAR-FACEBOW SELECTION
  • Use the patient’s recent maxillary study model to select an appropriate facebow allowing a 2-4 mm gap between the inner bow and incisors when the distal legs of adjustment loops are placed against the buccal surface of the first permanent molars.
  • Goal: Maintain about 2 mm of distal expansion while buccally moving the molars as they shift distally.
  • Recording Requirements: Document in the patient’s chart the facebow size, type of traction device and number of hours per day the patient is instructed to wear it.
    • Visual Reference: FIGURE 4.37 FACEBOW COURTESY OF IACT.