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(BQ) Part 1 book Orthodontics - Prep manual for undergraduates has contents: General considerations in treatment planning, methods of gaining space, removable appliances, removable appliances, removable appliances, removable appliances, removable appliances, preventive orthodontics, preventive orthodontics,... and other contents.
SECTION VI Orthodontic Appliances OUTLINE 18 Removable appliances 19 Functional appliances 20 Orthopaedic appliances 21 Expansion appliances 22 Fixed appliances CHAPTER 18 Removable appliances CHAPTER OUTLINE ❖ Definition and classification of orthodontic appliances ❖ Ideal requirements of orthodontic appliances ❖ Advantages and limitations of removable orthodontic appliances ❖ Mechanical principles involved in designing of removable appliances ❖ Components/Various parts of removable appliances ❖ Designing of clasps used in orthodontics ❖ Classification of clasps used in orthodontic practice ❖ Free-ended clasps ❖ Circumferential clasps ❖ Triangular clasp ❖ Ball end clasps ❖ Duyzing’s clasp ❖ Lingual extension clasp ❖ Continuous clasp ❖ Jackson’s clasp ❖ Arrowhead clasp ❖ Southend clasp ❖ Adams’ clasp ❖ Delta clasp ❖ Various active components of removable appliance ❖ Springs used in removable appliance ❖ Canine retractors ❖ Labial bows ❖ Screws ❖ Elastics ❖ Orthodontic pliers ❖ Base plate ❖ Hawley appliance and retainer ❖ Insertion of removable appliance ❖ Failures of removable appliance/unsuccessful removable appliance therapy ❖ Accessory points ❖ Advanced learning ❖ Designing of removable orthodontic appliances ❖ Fabrication of removable appliance ❖ Treatment of various malocclusions by removable mechanical appliances Definition and classification of orthodontic appliances Definition Orthodontic appliances are devices by means of which pressure may be applied to a tooth or group of teeth to move them in a predetermined direction Classification of orthodontic appliances There are different methods of classification I Simple classification Appliances • Removable • Mechanical • Functional • Fixed appliances • Mechanical • Functional Removable appliances: Appliances that are designed to be taken from the mouth by the patient Attached removable appliances maintain a fixed relationship to the dentition through clasps or other attachments Loose appliances fit imprecisely and alter the neuromuscular activity during function; also called functional appliances Passive appliances are used to maintain the existing occlusion (space maintainers and retention appliances) and to disocclude the dentition (bite-blocks) Passive appliances not exert force Mechanical appliances exert force to tooth or group of teeth through mechanical devices or active components II Detailed classification Appliances Removable appliances • Attached • Active Headgears Facemask Chin cups Lip bumpers Active plates – Hawley appliance – Space regainers – Schwarz expansion plates – Anterior spring aligners (Barrer appliance) – Crozat appliance – Vacuum formed appliances (invisible appliances) • Passive Space maintainers Bite planes Retainers Occlusal splints Posterior bite-blocks • Loose removable appliance/functional appliance Activator Bionator Frankel Twin block Fixed appliances • Mechanical Edgewise Begg PEA or preadjusted edgewise appliance Lingual orthodontic appliances • Functional Herbst Jasper Jumper Forsus Ideal requirements of orthodontic appliances Ideal requirements of orthodontic appliances can be studied under the following headings: Mechanical aspects ➤ Appliance should deliver light continuous force ➤ Appliance should have low load deflection rate ➤ It should have high maximum elastic load ➤ Should have control over centre of rotation ➤ Appliance should have self-limiting force, i.e if the patient misses appointment, force delivery should not occur ➤ Ease of fabrication is a requirement ➤ Appliances should be able to withstand forces from mastication Biological aspects ➤ Should be able to produce tooth movement in the desired direction ➤ Should not restrict normal growth ➤ Function should not be interfered ➤ Deleterious effects like root resorption, nonvitality should not be produced ➤ Frontal resorption is desirable panoramic, 184–186 paralleling technique, 182 Raphe median plane, 133–134 Rapid maxillary expansion, 419 history, 420 indications, 421 principles of, 432 Reciprocal anchorage, 279 Recovery heat treatment, 287–288 Recrystallization, annealing, 288 Registration point, Broadbent, 235 Reinforced anchorage, 281 Relapse, 615 causes, 615–617 definition, 615 Reminder appliance, therapy, 512 Remodeling, 18 definition, 18 types, 18 Removable appliances, 310–359 advantages, 313 clinical management, 347–348 designing of, 353–355 fabrication, 355–357 failures of, 350–358 limitations, 313 mechanical principles involved, 313–315 parts, 315–316 trimming, 357 uses in different types of malocclusion, 358 Removable space maintainer, 493–495 Repositioning of tooth, 533–534 Resilience, 314f, 315 Retained infantile swallow, 514 Retainers, 621–624 banded/bonded, 623 Essix, 623 fixed, 623–624 ideal requirements, 621 removable, 621–623 Retention, 615 definition, 615 in different types of malocclusion, 625–626 need for, 615–617 planning of, 619–620 schools of thought, 617 theorems on, 618–619 Retrodiscal pad, 51, 363f, 364f Reverse loop canine retractor, 331–332 Reverse piezoelectricity, 248–249 Reverse pull headgear, 414–417 biomechanics, 416–417 components, 414–416 effects of, 416 history, 414 indications, 414 types, 415 Ricketts analysis, 223–225 Roberts’ retractor, 358-359t Roche’s appliance, 499 Roll, 178 Rooting and placing reflexes, See Benjamin theory Root movement, 271f, 273 Root resorption, 265–266, 630t types, 263 Rotations of jaw, 41 clockwise and counterclockwise, 42 internal and external, 42f matrix and intramatrix, 42f Roth, keys of functional occlusion, 105–108 Rubella, 145, 303, 555 S Safety valve mechanism, 26 Sagittal split osteotomy, 540 Scammon’s growth curves, 23f Schwarz, clasp, 322–323 degree of forces, 263 expansion plate, 425–427 Scissors bite, 575, 591 Scott’s hypothesis, See Cartilaginous theory Screws, 345 Sealants, 439 Second messengers, 252 Self-correcting malocclusions, 102 Self-ligating brackets, 451 Sella, 215, 216t, 220, 235 Sella-nasion plane, 216t Sensitization, 291–292 Separators, 432 types, 432 Serial extraction, 475–476, 521–527 benefits of, 522 contraindications, 522 definition, 521 disadvantages, 524–527 indications, 522 rationale, 522 technique, 521, 524 Servo system theory, 49–52 and functional appliances, 407–408 Shape memory, 292–294 Sheldon’s classification of body build, 165b Short face, 588–589 clinical features, 463 principle in growth modification, 462–465 surgical management, 572, 602 Sicher’s sutural theory, 45 Simian space, 96 Simon’s classification of malocclusion, 134 Simple anchorage, 509–510 Simple tongue thrust, 512 Skeletal classification, 139 Skeletal malocclusion, 131, 140, 414, 526 Skeletal maturity indicators, 29 cervical vertebrae maturation, 30 hand-wrist radiographs, 29 Skeletal open bite, 587–588 Skeletal unit, 47 macro, 48t micro, 48t Skinner BF, operant conditioning, 83 Sliding genioplasty, 542, 543 Slow expansion appliance, 424–425 Smile analysis, 178–180 SNA angle, 217 SNB angle, 217–218 Soft tissue paradigm, 14 Soldering, 295–296 definition, 295 technical procedure, 296 South end clasp, 323 Space age wires, 292–294 Space gaining procedures, 460t, 468 Space maintainers, 485 active, 490–491 classification, 565–566 contraindications, 493 definition, 490 functional, 490–491, 495 ideal requirements, 493 indications, 493 non-functional, 490–491, 491f, 495 removable type, 493–495 Space maintenance, 491–493 definition, 491 planning, 491–492 Space regainers, 519–521 Spacing, 568–569 aetiology, 568–569 generalized, 568–569 localized, 568 management, 569 Speech types and malocclusion, 118–120 Spring characteristics, 315 Springiness, 315 Spring retainers, 626–627 Springs, 327 auxiliary, 328 basic properties, 328–339 definition, 327–328 free-ended, 328 guided, 328 ideal requirements, 328 self-supported, 327–328 Sprinkle on technique, 357 Squeeze film effect, 263 Stability ratio, 329 Stainless steel, 289–292 18-8 type, 289–292 definition, 289 properties, 290–291 Stationary anchorage, 278 Steiner’s analysis, 217–220 Sterilization, 303–306 definition, 303 monitoring of, 304–306 of orthodontic materials, 304 Stomatognathics, 109 components, 109 definition, 109 Straight wire appliance, See Preadjusted appliance Strain, 287, 314 Strain hardening, 287 Streaming potential, 249 Stress, 250f, 272, 283, 288, 293, 314 Study models, 196–200 advantages, 199 fabrication, 197 parts, 196–197 uses, 199 Superego, 77 Superelasticity, 293 Supernumerary tooth, 153 Supplemental diagnostic aids, 163 Supplemental tooth, 153 Surgical orthodontics, 528 definition, 287 procedures, 529–530 major, 529t minor, 529t Surgically assisted rapid palatal expansion (SARPE), 420, 423 Sved bite plane, 369 Swallowing, adult, 115, 117 infantile, 116 Swallowing exercises, 513, 526 Synchondroses, 31–33 definition, 32t intersphenoidal, 32t intraoccipital, 32t Syndromes causing malocclusion, 159t T Tanaka-Johnston analysis, 206–207 Temporomandibular dysfunction, 608 Terminal plane relationships, 97 distal step, 97 flush, 97 mesial step, 97 Terrible two’s stage, 99 Therapeutic aids, 545–548 Therapeutic extractions, 529 Third molars, 75, 106, 472, 617 Third order bends, 435–436 Through the bite elastics, 280, 445t, 579 Thumb sucking, 508 aetiology, 508–509 definition, 521 methods of approach and treatment, 511 pathogenesis, 509 Timing of treatment, 416, 457 Tip edge, 437 Tipping, 271f, 472 controlled, 272 uncontrolled, 271 Titanium-molybdenum alloy (TMA), 294 Tongue blade therapy, 506–507 Tongue development, 70–75 Tongue thrusting, 512–514 classification, 512–513 definition, 512–514 treatment, 513 Tooth material, 202, 461, 570 Tooth movement, biology of, 245–246 biomechanics of, 269 changes in other tissues, histological changes, 252 stages, 257–258 theories of, 247–252 types, 271–274 Torque, 104, 273 Total space analysis, 465 Trajectorial theory of bone formation, 110–111 Trajectories of forces, 111–113 mandible, 113 maxilla, 111–113 Transduction, 247, 364 Transient malocclusions, 102 Translation, 63 Transpalatal arch, 499 Transplantation, 534 Transposition of tooth, 566 Trauma, and orthodontics, 613 Treatment planning, 454–461 establishing goals of treatment, 455 for mixed dentition, 458 for primary dentition, 459 in adolescents, 460t in orthodontics, 454–461 timing of treatment, 457 Treatment priority index, 12–13 Triangular clasp, 319 Trident of habit factors, 151 T spring, 352t Tube shift technique, 163, 530 Tweed, 221–222 analysis, 221–222 diagnostic triangle, 221–222 growth trends, 39 retention plan, 629–630 technique of serial extraction, 524–527 Twin block, 402–408 clinical management, 404 components, 403–404 construction bite, 403–404 design, 403–404 Twinning, 153 Twins, 146 dizygotic, 146 monozygotic, 146 Twin study, 146 U Ugly duckling stage, 98–99 U-loop canine retractor, 332 Ultimate tensile strength, 314 Undermining resorption, 255–256 Unfavourable sequelae of malocclusion, 2–3 Universal pliers, 346 Unloaded nerve concept, 68 Upper anterior inclined plane, 347 Uprighting, 472 Utility arches, 585 V Variability in growth, 23–25 Veau’s classification of cleft lip and palate, 554 Venn diagram, 135, 136, 138 Vestibular screen, 372–375 Visick clasp, 317 Visualized treatment objective (VTO), 365–366 cephalometric, 244 Vital staining, 35 Vitamin D excess, 144t V principle, 21 W W arch expansion, 464 Wash board appearance, 604b Wassmund procedure, 543 Water holding test, 173t Welding, 297 WHO classification of malocclusion, 139–140 Wilkinson extraction, 474 Wires, 288 braided or twisted, 306 composition and properties of metallic, 306–307 ideal requirements, 289 non-metallic, 306 used in orthodontics, 289 Wits analysis, 222–223 Wolff’s law of transformation of bone, 110–111 Working side, 123 Wrap around retainer, 621 Wrought alloys, 287 X Xenon, 308t Xeroradiography, 191 X rays, See Radiographs Y Yaw, 178 Y axis, 220–221 Yield strength, 314 Z Zinc phosphate cement, 298 Zinc polycarboxylate cement, 298 Z spring, 320–321 Zygomatic pillar, 111f ... When a force is applied to a beam, its response can be analysed with the diagram (Fig 18 .2) and definitions FIG 18 .2 Application of force Relationship between stress, strain and resilience, formability... buccal surface ➤ End of the clasp is fabricated in the form of a ball or knob ➤ They are available as ready-made forms ➤ Instead of the ready-made ball, the end of the wire can be recurved to make... continuous force ➤ Appliance should have low load deflection rate ➤ It should have high maximum elastic load ➤ Should have control over centre of rotation ➤ Appliance should have self-limiting force,