18Assessment of malocclusion_240519_004424 (1).pdf

Assessment of malocclusion Dr. D D Vithanachchi 5th semester 2023 Intended Learning Outcomes At the end of the lecture,you should be able to Describe the method available to formulate a database for an Orthodontic patient. Apply this knowledge clinically and build up...

Assessment of malocclusion Dr. D D Vithanachchi 5th semester 2023 Intended Learning Outcomes At the end of the lecture,you should be able to Describe the method available to formulate a database for an Orthodontic patient. Apply this knowledge clinically and build up a database for overall diagnosis of the orthodontic patient Assessment of malocclusion The purpose of an orthodontic assessment is to gather information about the patient to produce an accurate orthodontic diagnosis  History Taking Personal data – Name, TP, Address, sex, Date of birth. Physical growth status (identifying whether growth is complete or still ongoing- Patient’s complaint Dental history including trauma history Medical history Family History Social History Habits Patient (or parent’s) motivation Presenting complaint Functional (speech or mastication difficulties) Related to dental health (like a traumatic overbite) Aesthetics In patient's words-Not technical terms My teeth are crooked/sloping backwards/Missing teeth/not straight My teeth are jutting out Past Dental history Experience in restorations,scalings Previous orthodontic treatment Who did the treatment,[GDP,Technician, Orthodontist) Whether teeth have been extracted, What type of appliance used To minimize side effects and medico legal problems Trauma history External replacement root resorption  Past Medical history No absolute contra indication, Few medical conditions limit the treatment Epilepsy Allergies-to drugs, latex,nikel, Bleeding disorders Cardiac diseases Diabetes Asthma Patients with cancer on radiotherapy and chemotherapy- short roots On any tablets, pill Eg – Bis-phosphonates, Na Valproate Pregnancy  Habits Can cause malocclusions Eg- Thumb sucking Can interfere with orthodontic treatment Eg- Nail / pencil biting Type,Duration, Intensity Clinical Extra Oral Intra Oral Examination Examination Examination Extra Oral Examination Frontal view (assessing in Profile view (assessing in the the vertical and transverse planes) anteroposterior and vertical planes) Natural Head position Frontal examination 1/3 1/3 1/3 Verticle 1/3 Facial Assymetry Occlusal cant with facial assymetry  Profile Examination convex straight concave Vertical facial proportions Profile divided into thirds 1/3 In a well-balanced face,can be divided into equal thirds 1/3 Upper,middle,lower Variations affect facial 1/3 appearance Airway Nasal breathing Oral breathing Adenoid facies  Skeletal relationships  Antero –Posterior Skeletal Verticle relationships Transverse Anatomic Landmarks Natural Head position Skeletal pattern Antero –Posterior relationship between maxilla and mandible in centric occlussion Class I Class II Class III Clinical assessment of the skeletal pattern Tip of the index finger-concavity between the base of the nose and the vermillion border of the upper lip Tip of the middle finger at the vermillion border of the lower lip and the bony chin Vertical Relationship Linear Angular Verticle skeletal relationship ( Angular measurement) Frankfort mandibular plain angle ( FMPA) Average Increased/High Reduced/Low Measurement of the lower facial height. (Linear measurement) 1/2 1/2 TRANSVERSE SKELETAL RELATIONSHIP Difficult to see extra orally Can manifest intra orally as posterior crossbites or Scissors bites  A difference in transverse size between two symmetrical bases Causes for A true asymmetry in one or both transverse bases skeletal malrelationship An incorrect antero posterior relationship of the skeletal bases rather than a difference in size  Soft tissue examination Soft tissue examination vLip competence vLip line Resting lip length and incisor coverage vLip morphology vTongue Size vTongue during activity  The Neutral Zone  Lip competence Upper and lower lips are brought together without undue contraction of lip muscles at rest Causes for incompetence Short upper lip Increased anterior lower facial height Severe antero- posterior skeletal discrepancy Nasal obstruction and mouth breathing Interposition of the teeth between lips  Lip line Relationship of the upper border of the lower lip to the upper incisor Normally-lower lip covers the incisal 1/3 rd of the upper incisors on the labial surface Related to the etiology of malocclusion To judge the stability at the end of treatment  Lip Morphology (form/contour) Lip morphology affect tooth position Average Full and everted Tight and vertical slight amount of large area of mucosa Vermilion demarcation mucosa visible beyond visible beyond the with oral mucosa is not vermillion zone vermilion zone visible Other Soft tissue features Short upper lip lip trap  Tongue vSize- Normal or Larger vAt rest -Resting tongue posture  Swallowing Sequence of events in Oral Phase 1.Lip seal is obtained with minimal muscular effort. 2.Tip of the tongue is lightly applied to the palatal mucosa behind the upper incisors 3.Teeth are brought lightly into occlusion, and 4.The floor of the mouth is elevated by the action of mylohyoid muscle bringing the remainder of the tongue into contact with the hard palate so that the bolus is passed to the pharynx  v Normal tongue thrust v Adaptive tongue thrust Tongue during activity v Endogenous tongue thrust Mandibular path of closure Mandibular path of closure vDisplacement- Forward Lateral vDeviation Displacement When the patient is closing the mouth from rest position to centric occlution with a hinge movement ( condyle head at centric relation) Forward displacement/ Pre mature contact lateral displacement of the mandible Deviation Habitual posture of the mandible( Sunday bite) Patients with class II Skeletal bases tend to posture the mandible forward to mask the discrepancy between the jaws It is a habitual rest position  Intra Oral examination  To assess patients presenting complain To help identify etiology of the malocclusion Intra Oral To determine how the other factors modify examination treatment planning. Eg; Level of oral hygiene, caries,Periodontal disease  Systematically and logically By inspection(visual examination) How is it done? palpation Further investigations(Radiographs,Vitality tests) Intra Oral Examination 1. Stage of dental development (by charting the teeth present) 2. Soft tissues and periodontium for pathology 3. Oral hygiene 4. Overall dental health, including identifying any caries and restorations 5. Tooth position within each arch 6. Tooth position between arches Stage of dental development (by charting the teeth present) Count teeth Mobility of deciduous teeth Compare the events on both sides If different suspect- absence,submergence,ectopy Palpate buccal/labial/lingual or palatal mucosa if tooth are missing/ over retain primary. Soft tissues and periodontium for pathology & Oral hygiene Asses oral mucosa for any lesions Basic periodontal examination High labial frenal attachment Gingival recession Overall dental health, including identifying any caries and restorations Caries Areas of hypomineralisation Effects of previous trauma Discoloured tooth Tooth wear Teeth of abnormal size or shape Existing restorations Examine Lower arch Upper arch Teeth in Occlusion Tooth position within each arch Crowding or spacing Alignment of teeth, including displacements or rotations of teeth Inclination of the labial segments (proclined, upright or retroclined) Angulation of the canines (mesial, upright or distal) Arch shape and symmetry Depth of Curve of Spee  Labial segment v4 incisors or incisors + canines EACH ARCH Buccal segment Crowding( Labial segment) 0–4 mm = Mild crowding 4–8 mm = Moderate crowding > 8 mm = Severe crowding Severe Mild Moderate ANGULATION ( mesio distal tip) Inclination v Upper incisors - 1050 +- 50 v Lower incisors- 900 v Normal/Procline /Retrocline Rotations Furthest away from the line of the arch Eg: 11 Mesio labialy 30 degree rotated  Tooth position between arches Over jet Horizontal distance between the labial surface of the tips of upper incisors and the labial surface of the lower incisors Centric occlusion, ruler is held parallel to the occusal plane OJ of both incisors can be recorded Overbite Vertical overlap of the incisors Average - Upper incisor covers 1/3 of lower incisor Increased,decreased Complete/Incomplete Complete-hard palate, teeth Traumatic-gingival recession, soreness Incomplete-Anterior open bite Anterior Open Bite-Measure using a ruler Centerlines Upper and lower midlines are assessed relative to each other and to the midline of the face Record the discrepancy in millimeters In relation to face-coincident or positioned to the right or left. Orthodontic treatment point of view it is important to correct midline to get maximum intercuspation and class I relationship.  Inclination Crowding and spacing Buccal Angulations segments Rotations Marked tooth malpositions Normal buccal occlusion The buccal cusp of the lower teeth occlude with the central fossae of the upper teeth Crossbites Anterior crossbite Posterior crossbite One or more teeth of the upper Buccal cusp of one or more upper teeth labial segment occlude lingual to occlde in the central fossae in lower opposing the incisal edges of corresponding buccal teeth lower teeth Scissors bite The buccal cusps of the lower teeth occlude lingual to the lingual cusps of the upper teeth Classification of malocclution Angles classification Canine classification BRITISH STANDARD INSTITUTE INCISOR CLASSIFICATION Palatal anatomy or the cingulum plateau is important Class I – Class II Class III Investigations Radiographs Vitality tests Classification and diagnosis All the features of the Other features- face and the occlusion is Incisor relationship displacements,persistent considered habits Early mixed/Middle Skeletal base Type of dentition mixed/Late relationship mixed/Permanent Diagnosis ?? Diagnosis ?? summery vHistory vExtra oral examination Frontal Profile Skeletal relationships Soft tissues Mandibular path of closure vIntra oral examination Each arch seperately for crowding, Inclination , Angulation In occlusion for overjet, overbite , crossbites scissors bite, midline v Relationship of upper and lower arches