Ortho - Final Review - Complete.pdf

Ortho – Final Review Week 1 o Dr Edward Angle – Devised the first classification for malocclusions o Also started the first school of orthodontics o 3 Goals of Modern Orthodontics: o Best occlusal relationship o S...

Ortho – Final Review Week 1 o Dr Edward Angle – Devised the first classification for malocclusions o Also started the first school of orthodontics o 3 Goals of Modern Orthodontics: o Best occlusal relationship o Stable occlusal result o Acceptable facial esthetics Week 2 o Early Intervention (Phase I Ortho) Indications: o Early or late loss of teeth o Di iculty chewing/biting o Mouth breathing o Thumb sucking o Crowding, misplaced, or blocked teeth o Cross bite, shifting jaws, or popping/clicking o Speech problems o Biting cheek/roof of mouth o Facial imbalances o Jaws too far forward/back o Grinding/Clenching o Primary Dentition – Classification o Listed as either: Distal Step, Flush Terminal Plane, and Mesial Step  o Flush Terminal Plane is the normal relationship in primary dentition. o Mesial Step will likely develop into CL1 or CL III o Ideally primary dentition has:  spacing – known as primate space  Broad, ovoid arches o Ugly Duckling Phase o Stage of dental development during incisor transition. o Characterized by:  Linguoversion of mandibular lateral incisors  Flared maxillary lateral incisors  Diastema between max central incsiors Ortho – Final Review _______________________________________________ o Malocclusion Causes: o Genetics o Habits o Trauma o Disease o Malnutrition o Somethings you may see in private practice o Congenitally missing teeth  Most commonly missing teeth (in order):  Wisdom teeth  Mandibular 2nd premolar  Maxillary lateral incisors ______________________________________________ o Approx only 50% of the root is formed when the tooth eruption begins, o Eruption Patter of permanent teeth o Mama Is In Pain Papa Can Make Medicine  **general rule, and mandibular first EXCEPT* canines ******** o Some problems associated with eruption:  Ankylosis Ortho – Final Review  Fusion of cementum to the bone o Most commonly a ected: Mandibular primary first molar  Ectopic  Permanent tooth erupts out of normal alignment  Can cause abnormal resorption of a primary tooth o Most commonly a ected: Permanent maxillary 1st molars (16/26) o Anomalies in Enamel: o Amelogenesis Imperfecta  Yellow-Brown colouration of teeth  4 Types:  Type 1: Hypoplasia o Most common o Localized defect, pitting  Type 2: Hypomaturation o Enamel is softer, thin and may chip o Enamel is mottled brown-yellow-white color, incisal edges are SNOW COLORED  Type 3 o Enamel is normal thickness but very soft and easily lost by attrition. o Enamel looks dull – honey colored, and stains easily.  Type 4 o a combination of all of the above types ______________________________________________ o An RDH in ON still requires a direct order for ortho and restorative o Ortho by an RDH: cementing a previously fitted ortho appliance o Bonding and debonding brackets and bands o Ligating and preparing orthodontic arch wires o Fabricating study models and mouthguards o Debanding orthodontic appliances o Ceph tracings Week 3 o Initial Diagnostic Records: o Comprehensive ortho exam  Review Med/Dent  Chief Complain  Physical growth, social and behavioural eval.  Facial analysis and assessment  o Pan or FMS Ortho – Final Review Evaluate IO and surrounding dental and skeletal structures  Caries, Apical Involvement, Abnormal masts, unerupted/impacted teeth, missing/supernumerary teeth, exfoliation sequence, jaw fractures, etc. o Ceph xray  Key tool to evaluate skeletal pattern prior to ortho treatment.  Evaluates the skeletal and dental dimensions and inter-relationships  Evaluates growth pattern in teenagers  Checks airway issues  Checks position of maxilla and mandible  Indicates asymmetric growth  Establishes a baseline for monitoring growth  Soft tissue profile o IOEO photos  To record initial condition of soft and hard tissue  Shows the intercuspation and occlusion of teeth  Occlusal photos to show severity of crowding o Study Models  Visual aid – shape of current dental state o Tomogram (case dependent)  Evaluates the TMJ for form, position and function. ______________________________________________ o AAO recommends that every child has an ortho check no later than 7 years old. o This is because enough of the permanent teeth have erupted to evaluate the relationship of teeth, jaws, and face. o Six Keys of Normal Occlusion – contribute individually and collectively to the total scheme of occlusion and therefore are viewed as essential to successful orthodontic treatment. o Class I Molar Relationship o Mesial Crown Angulation  Refers to the angulation “tip” of the long axis of the crown, not the entire tooth.  The long axis of the crown for all teeth, except molars, is judged to be the mid-developmental ridge. This is the most prominent and center-most vertical position of the labial or buccal surface of the crown  The long axis of the molar crown is identified by the dominant vertical groove on the buccal surface of the crown.  ** explained in simpler terms: o Crown Angulation: This refers to the angle or tilt of the top part of the tooth, not the whole tooth itself. o Why it Matters: In orthodontics, we focus on the alignment of the visible part of the teeth (the crowns), since that's what we work with and what people see. o Where to Measure: To measure crown angulation, we look at the part of the tooth that's closer to the gums (gingiva) and compare it to the part of the tooth that's closer to the tip (incisal). This varies depending on the type of tooth. o How to Find the Center: For most teeth, except molars, we consider the mid-developmental ridge as the centerline. This ridge is the tallest and most centered part of the tooth's front or cheek side (labial or buccal surface).  The developmental ridge is a raised, linear feature on the surface of a tooth that forms during its development. Ortho – Final Review o Finding the Center of Molars: For molars, we look at the most prominent groove on the front or cheek side (labial or buccal surface) to find the centerline. o Proper Crown Inclination  Labiolingual/Buccolingual inclina on of the long axis of the crown (not the en re tooth)  o No rotation o Tight Contacts o Flat Occlusal Plan  Generally flat, to a slight curve of Spee o Assessing a Ceph Xrays: o Used for evaluation of soft tissue  Line is drawn from soft tissue chin to a point halfway between the base and the tip of the nose  Normal – lips fall on the line  Convex – lips fall ahead of the line  Concave – lips fall behind the line o Position of maxilla/mandible  Cl I – Skeletal – normal maxilla and mandible  CL II Skeletal – Maxilla is normal, mandible is retrognathic (more common – 95%) o Maxilla is prognathic and mandible is normal (5%)  CL III – Skeletal – Maxilla is retrognathic, mandible is normal (80%) o Maxilla is normal, mandible is prognathic (20% o Airway evaluation o Severity of malocclusion, types of malocclusion, vertical problems, and inclination of incisors. o Materials used for Ceph Tracing:  Pencils and millimeter rules o Technique for Tracing  Lateral headplate faces to the right  Shiny side down  No tape at the bottom of the paper so it can be easily lifter  Client name/date/age and name of DDS ______________________________________________ o Phase I o Typically mixed dentition Ortho – Final Review o Removable or functional appliances o Corrects skeletal problems o Habit cessation o Phase II o Invisalign, Lingual Brackets, and Modified Straight Wire Technique-Braces o Phase III ______________________________________________ o Obstructive Sleep Apnea o Sleep apnea is defined as 30+ apneic episodes (cessation of breathing through mouth or nose for 10+ sec) occurring during 7 hours of nocturnal sleep  It will last anywhere between 10-20s, stopping with at least a partial wakening o Obstruc ve Sleep Apnea has 4 components:  First – airway collapses or obstructed  Second – effort is made to be breath, but it is unsuccessful  Third – The oxygen level in blood drops d/t unsuccessful breathing  Last – amount of oxygen in the brain decreases, the brain signals the body to wake up and breathe o Causes:  Airflow  Deviated septum  Turbinates  These are filters in the nose that can obstruct airflow when they become swollen (allergies and nasal conges on)  Polyps  Become large and block nasal passage  Tonsils and Uvula  Large/elongated can constrict breathing  May* be surgically corrects  Tongue  Tongue falls backwards and obstructs breathing (especially those that sleep on the back – and even more so for class II pa ents with a retrusive mandible) o Prevalence and Effects  Obese pa ents – 70% have OSA  Heart Disease – 30-50% have OSA  Strokes – 60% have OSA  Effects:  High BP, Heart Failure, Atherosclero c Heart Disease, Pulmonary Hypertension, Insulin Resistance  The risk of conges ve heart failure increase by 2.3X  Risk of stroke increases by 1.5X o Treatment:  Dental Appliances – first choice for mild-moderate OSA Ortho – Final Review  Holds mandible in a more anterior posi on, and brings the tongue forward  May cause stress to the TMJ  CPAP – first choice for SEVERE cases  Uses air pressure to hold the ssues open during sleep  Medica on  To provide relief of nasal conges on/allergies to help open air  Surgical Treatment  Severe OSA not able to be treated with tradi onal methods o “Red Flags” of OSA o High BP, Cardiac Problems, Class II Malocclusions, Obesity, Alcohol use/Seda ves, Snoring, Gene cs, Large Neck Circumference (16in, or 17 in) o Large, flat, and low posteriorly posi oned tongue o High vaulted and narrow palate o Enlarged tonsils/adenoids o Class II, crossbite, constricted maxilla o Edentulous, GERD, Bruxism (IO signs) ______________________________________________ o Orthodontic Appliances: o Phases or Orthodontics o Phase 1  Passive management of space  Preservation of space during developing years  Ex – early loss/prolonged retention of primary molars  Space Maintainer Space Maintainer Shwartz - < 13 y.o - Turn 2x/week - Expands 2mm per MONTH Banded Hyrax - RAPID palatal expander - Requires separator - Turn 1-2x/DAY - Expands 1.75-3.5mm PER DAY Ortho – Final Review Bonded Hyrax - Same process as above - Does NOT require separators - Occlusal pads on posterior to help correct crossbite “W” Expander or Quad Helix - Anchored to permanent molars - Does not split palate Transpalatal or Lingual Arch - Maintains expansion after expanding the palate - Used if exo’s are indicated - Maintains oral arch length Nance Holding Arch - Used after expanding the premaxilla with a sagittal appliance - Maintains total arch length MANDIBULAR ADVANCING APPLIANCES Bionator - Holds mandible in anterior position and guides eruption Ortho – Final Review Twin Block - 2 separate appliances worn on upper and lower at the same time - Better acceptance than the bionator Herbst Appliance - Fixed – can’t be removed - Holds back the maxilla and enhances growth of mandible - Mara appliance does the same – see second photo Rick – A – Nator - Advances Mandible - Corrects CLII to CL I - Eliminates deep overbite & deep curve of Spee - Used for minor jaw discrepancies MAXILLARY DISTALIZING APPLIANCES ADVANCING APPLIANCES Distal Jet - Distalizes first molars Pendulum - Eliminates the need to wear a headgear or functional appliance - Uses the angle of the hard palate as an anchor to distalize the molars Pendex - Incorporates a hyrax + pendulum - Expansion screw to widen arch - Distalizes molars Ortho – Final Review Headgear - Worn for 14-16 hours per day - Regular pull = retrudes maxillary molars - High pull = intrudes maxillary molars Petit Class III Face Mask (AKA – Reverse Headgear) - Treats maxillary insu iciencies - Treats mandibular prognathism (CLIII) o Phase 2  Final correction of tooth position, function and/or skeletal problems o Phase 3 WEEK 10 o Proxy Brushes – Most common and best choice to clean around braces o Foods to avoid with braces: hard, sticky, acidic, and foods with high sugar content. o Acidic foods can lead to decalcification WEEK 11 o Orthodontic Instruments and Intra-Oral Mechanics: Bird Beak Plier - 2 beaks – one round and one flat - Use: bend/form ortho wires Weingart Utility Plier - General plier, used to place/remove wires - Usef for heavier square/rectangle wires Howe Plier - Similar to Weingart (place/remove wires) - Also checks for loose bands & removes separators (stainless steel separators) - Rubber separators can be removed with explorer or scaler Distal End Cutter - Cuts distal ends of wire - Holds the wire after its cut so it doesn’t fall into oral cavity Ortho – Final Review Mathieu Plier (Hemostat) - Use: placing plastic elastics around brackets and powerchairs - Used for placement of light, round wires only Separating Plier: - Use: placing posterior separators - Beaks have small groves to hold separator during placement Band Remover: - Removable nylon tip on occlusal surface - Squeeze band remover to break and release the cement bond o o Intral-Oral Mechanics Separators - Separating teeth prior to banding - Placed 1 week before - Radiographically: they are radiopaque Elastics - AKA: O-Rings, Ties, and Donuts - Must be changed every 4 weeks Power Chain - Also must be changed every 4 weeks - Used to close space within an arch (intra) Kobayashi Hooks (K-Hooks) - Put around a bracket to create a power arm to attach elastics Closing Coil Spring - Used to close spaces within the SAME arch (intra arch) - Does not lose force like an elastic power chain Open Coil - Used to OPEN and create space INTRA = WITHIN THE SAME ARCH WEEK 12 Ortho – Final Review o Seating a band o Place over tooth and seat manually first o Use bite stick and have patient bite down on it o The band should be parallel to occlusal surface o Parts of a Bracket: o You should use the ANATOMICAL crown when placing a bracket o The arch wire slot should always be parallel to the incisal/occlusal plane o Measuring bracket placement o Measure from center of bracket to incisal edge o Maxillary Placement:  o Mandibular Placement:  o Tooth Preparation Prior to Bonding: o Prophylaxis with NON-fluoridated polishing (pumice) o Etching- 37-40% phosphoric acid for 45 seconds o A sealant/primer is importance for getting an ideal bond o Ensure “Flash” (excess cement) is removed. This is especially important for oral hygiene o Note: The indicator dot sits gingivally and distally o Incorrect Bracket Placement: o Too high (gingivally) = extrude the tooth o Too low (incisally) = intrude the tooth o Not parallel with incisal edge = tipping o Too mesially = rotates tooth distally o Cause of bond failure: moisture control inadequate WEEK 13 o Retention: o A retainer minimizes post-treatment changes but does not prevent relapse Ortho – Final Review o A Hawley Retainer is the most commonly used retainer o Essix Retainer  Clear, can be worn all the time (except eating), more fragile, NOT recommended for bruxism prevention o Tooth Positioner:  Worn at night – maintains or finalizes tooth position o Spring Appliance:  Great for minor relapse rotations  Worn 24/7 – only removed to eat o Interproximal Reduction (IPR) o Interprox is reduced with mini sand paper disk o Can be used to eliminate “dark” triangles/large embrasure spaces o Lingual Wires o Polish (pumice), etch for 45 sec, rinse + dry (frosty), seal o Recommend: Floss threader/superfloss, Waterpik, Sulcabrush WEEK 14 o Tooth Movement o PDL  Source of proliferating cellular elements when stimulated by pressure or tension (compression + stretching)  Cells in the PDL include: mesenchymal cells, fibroblasts/clasts, osteoblasts/clasts, cementoblasts/clasts  The PDL has fluid and elastic properties, making is Viscoelastic  Pressure on PDL stimulates OSTEOCLASTS  Tension on PDL stimulates OSTEOBLASTS o Bone  Osteoblast = create apposition (building) of the bone  Osteoclast = create resorption (destroying) of the bone  Maxilla is thinner – allowing for more rapid movement in maxilla o Theories of Tooth Movement o Piezoelectric Therapy  Electric charge is produced when stress is applied (PDL gets compressed or stretched) which signals a bending in the alveolar bone and stimulates a cellular response o Pressure/Tension Therapy  Release of chemical mediators in response to altered blood flow due to compressed/stretching of PDL o Teeth move in the direction of pressure o PDL are partially compressed on pressure side which alters blood flow o Cellular di erentiation occurs within 4 hours (osteoblasts and osteoclasts) o The principle cell involved in control of both FORMATION and RESORPTION = Obsteoblasts  Osteoblasts release secondary messengers to activate osteoclasts Ortho – Final Review  Osteoblasts take 3 months minimum to rebuild bone  Osteoclasts take about 3 days to begin o Factors A ecting Force o Magnitude  Less force = better (more stable results with less risk of root resorption) o Direction  Teeth move in direction with least resistance o Duration  Amount of time that an appliance used will e ect force  Ex: head gear is not worn for 14-16 hours = poor results o Distribution  Single force = more e ective than several di erent types of forces o Types of Orthodontic movements o Tipping – crown and root move in opposite directions, occurs at the center of resistance o Translation – crown and root move together in the same direction o Rotation o Extrusion – vertical movement; force on the pdl o Intrusion – vertical movement; force concentrated @ apex o Torque-Specific – roots only, crown remains stable o Types of Force: o Continuous  Same amount of force over an indefinite period of time  Ex: spring loaded expansion coils o Dissipating  Continuous force that will ease up to allow a period of recovery  Ex: elastics, power chains o Intermittent  Force created by push/pull of PDL  Ex: Associated with removable appliances o Functional  Appliances to a ect craniofacial skeletal growth  Ex: Bionators, Twin Blocks o Issues associated with ortho o Root Resorption and loss of periodontal attachment o Cause: excessive force/duration, intermittent force caused by inconsistent wearing of ortho appliances o Heavy forces can be damaging to pulp/root  Hyalinization = loss of all cells due to eliminating the blood supply  Can occur with light forces too but to a lesser extent o Pain – usually worse with greater forces, pain with ortho is usually associated with ischemia (decreased blood blow)  Chewing gum and cold water rinsing can help alleviate pain o Initial Wires Ortho – Final Review o Levels crowns of teeth and rotates into proper position o They are braided or round o Working Wires o Usually square or rectangle o Used once teeth are rotated and leveled o Finishing Wires o Rectangle; torque roots of teeth WEEK 15 o General Dentists will handle less comprehensive ortho cases o Child Orthodontic Treatment Considerations: o Address functional and airway problems early o Warning signs for orthodontic needs: eruption issues, biting/chewing concerns, mouth breaking, oral habits (finger sucking), crowing/misplaced teeth, TMJ concerns, protruded/retruded jaw, clenching/grinding, speech problems, cheek biting, protruding teeth, facial imbalance,