Intro Flashcards
orthodontics is
Speciality of dentistry concerned with: - Growth and development of teeth, face and jaws - Diagnosis, prevention and correction of dental and facial irregularities
what does orthodontic assessment include
systematic evaluation of the face and skeletal bases in 3D Position of the teeth depend to a large extent on the size, shape and relative position of the underlying bones (i.e. the maxilla and mandible)
position of teeth depend on
depend to a large extent on the size, shape and relative position of the underlying bones (i.e. the maxilla and mandible)
what is the key skeletal relationship that impacts occlusion
relation ship of jaw Where does maxilla line in relation to mandible – anteroposterior skeletal relationship
Frankfurt plane
Top of ear hole to orbital rim needs to parallel to floor for orthodontic assessment Reproducible by getting pt to stare into own eyes in mirror
what is ignored in orthodontic assessment
Chin completely separate from mandible – not used in assessment
2 bone points used in orthodontic assessment
Basal bone of maxilla –curvature of upper lip, below nose Innermost curvature of lower lip mandible
Class 1 skeletal relationship
mandible 2-3mm behind maxilla - normal
class 2 skeletal relationship
maxillary base is in front of mandible significantly (10mm approx.) expect overjet teeth
class 3 skeletal relationship
maxillary base is in line with mandible reverse overjet expected
mandibular hypoplasia causes
CLASS 2 Juvenile arthritis condyle crumbling Smaller lower jaw
mandibular prognathism and maxillary hypoplasia causes
CLASS 3 Large lower jaw And smaller upper jaw
orthodontic dimensions
3D problem – facial asymmetry - Hemimandibular hypertrophy
Hemimandibular hypertrophy
3D problem -> facial asymmetry Many female late teen – early 20s Gradual onset Lack eruption on one side undereruption on other side causing maxillary cant
hemifacial microsomia
syndrome Failure to develop condyle, ramus and body to differing tegress Progressive facial asymmetry Can graft (2/3 successful)
example of syndrome impacting orthodontics
hemifacial microsomia
Mandibular retromaphia causes
class 2 point A (maxilla) in front of B (mandible)
lateral cephalometry taken when
Only take if skeletal problem – so only class 2 or 3
orthodontic tx options for skeletal discrepancies
Growing patients - Growth modification techniques to promote or restrict growth of either jaw Adults who have completed growth - Orthognathic Surgery
growing patients orthodontic Tx options for skeletal discrepancies measn
growth modification
orthodontic appliances to alter growth in skeletal discrepancies of growing pts (3)
Functional appliances – grow mandible (wear 24 hours a day) Headgear – reduce maxillary Reverse pull facemask and RME – promote maxillary growth
orthognathic surgery
- split and move Single jaw or bimaxillary procedures
orthodontic treatment for adults who have completed growth but have skeletal discrepanacies
orthognathic surgery
BSSO
Bilateral Sagittal Split Osteotomy
orthognathic surgery for maxilla
le fort 1
orthognathic surgery for mandible
Bilateral Sagittal Split Osteotomy BSSO
le fort 1
Split bone and pull forward Secured my pins and screws
BSSO
Inside behind nerve and mandible around lower molars Slide mandible forwards of back Careful of nerve
orthognathic team (6)
Orthodontist Maxillofacial Surgeon Clinical Psychologist – ensure pt knows what impact will be Maxillofacial Technician Speech Therapist GDP
cleft lip and palate prevalence and causes
1 in 700 live births Multifactorial - Cleft lip or Cleft palate or Cleft lip and palate Unilateral or Bilateral
cleft lip and palate team (7)
Orthodontist cleft surgeon ENT Speech therapy Max-fac surgeon Plastic surgeon Dental practitioner
what can go wrong in growth and development of teet?
Increased overjet Deep overbite Anterior cross bite Posterior cross bite Retained deciduous teeth Early loss of deciduous teeth Ectopic teeth Impacted first molars Crowding Spacing Trauma Habits Anterior open bites Lateral open bites Ankylosis of deciduous teeth Cysts Diastema Supernumeraries Dental asymmetries
role of dentist and orthodontist in diagnosis
Watch developing occlusion for issues and intercept to alleviate
anterior eruption norm
centrals before laterals issue in sequence of eruption -> refer
orthodontic diagnosis consists of
Careful systematic assessment of teeth, face and jaws (Lecture 2) - Facial anomalies, asymmetries - Skeletal relationship (how the jaws relate to each other) - Skeletal relationship (how the jaws relate the skull base) - Teeth in each arch separately - Occlusion (how they bite together) Study models Radiographs - Orthopantomogram (OPG) - Lateral Cephalogram – if skeletal issue Photographs – before and after Tx Sensibility tests Cone beam CT scan
key aims of orthodontic Tx (3)
stable functional aesthetic occlusion done prior to restorative work try to recreate the ideal occlusion - Andrew’s 6 keys
types of orthodontic appliances
Removable Functionals Fixed Others - Aligners, Invisalign replace every 3-4 weeks - Headgear and reverse pull HG - Temporary anchorage devices last 10-15 years, screws to move teeth
removable appliances
tip teeth, open bites, maintain space start the job often - Growing patient
functional appliances
modify jaw growth
fixed appliances
true 3D control of tooth protrusion (traintracks)
benefits of ortho
Improve function - e.g. anterior cross bite or anterior open bite can make it difficult to incise food improve appearance (aesthetics) improve dental health (make teeth more easy to clean) Reduce risk of trauma To facilitate other dental treatment - E.g. rearrange spaces in hypodontia cases prior to bridges or implants – right size for it
3 key risks of ortho
Decalcification Relapse Root resorption
risks of ortho
Decalcification Relapse – hence retainers Root resorption - Pain, discomfort - Soft tissue trauma - Failure to complete treatment - Loss of tooth vitality - Inhale or swallow small components - Candidal infections
who do orthodontists treat
not limited to adolescence 30% of our patients are adults treatment in the mixed dentition for some cases (interception) Early treatment of facial anomalies Cleft lip and palate cases may require very early treatment (just after birth)
why do we do orthodontics studying
Interesting Stimulating Technically demanding and hands on Infinite variety of malocclusions and problems Good patient population
Which of the following may be used to assess the antero-posterior skeletal pattern CLINICALLY? a. Incisor relationship (BSI) b. Mandibular unit length c. Maxillo-mandibular planes angle (MMPA) d. Palpation of the skeletal bases e. Molar relationship
d. Palpation of the skeletal bases
Which of the following can be used to assess the vertical skeletal pattern CLINICALLY? a. Lower anterior face height /upper anterior face height x 100 b. The Frankfort-Mandibular Planes Angle (FMPA) c. Lower anterior face height + upper anterior face height x 100 d. Frankfort-Maxillarly Planes Angle (FMxPA) e. Total anterior face height /upper anterior face height x 100
d. Frankfort-Maxillarly Planes Angle (FMxPA)
Which two soft tissue landmarks are used to construct the Frankfort Plane? a. Porion and Pogonion b. Gonion and Pogonion c. Gonion and Menton d. Porion and Orbitale e. Alar and Tragus
d. Porion and Orbitale Prosthodontists use the Alar-Tragus Line as an approximation to the Maxillary Plane
Which two soft tissue landmarks are used to construct the Manibular Plane? a. Porion and Menton b. Alar and Tragus c. Gonion and Menton d. Porion and Orbitale e. Gonion and Pogonion
c. Gonion and Menton
What is the definition of a Class 1 incisor relationship? a. The lower incisor edges are in contact with or below to the cingulum plateau of the upper incisors. b. The lower incisor edges lie posterior to the cingulum plateau of the upper incisors, there is an increased overjet. c. The lower incisor edges in contact with or below to the cingulum plateau of the upper incisors, there is an increased overjet and the incisors are usually proclined. d. The lower incisor edges in contact with or below to the cingulum plateau of the upper incisors, there is an reduced overjet and the upper central incisors are retroclined. e. The lower incisor edges lie anterior to the cingulum plateau of the upper incisors, the overjet is reduced or may be reversed.
a. The lower incisor edges are in contact with or below to the cingulum plateau of the upper incisors.
What is the definition of a Class II division 1 incisor relationship? a. The lower incisor edges lie anterior to the cingulum plateau of the upper incisors, there is an increased overjet and the incisors are usually proclined. b. The lower incisor edges lie posterior to the cingulum plateau of the upper incisors, there is an increased overjet and the incisors are usually proclined. c. The lower incisor edges lie posterior to the cingulum plateau of the upper incisors, there is an increased overjet and the incisors are usually retroclined. d. The lower incisor edges lie posterior to the cingulum plateau of the upper incisors, there is an decreased overjet and the incisors are usually retroclined. e. The lower incisor edges lie posterior to the cingulum plateau of the upper incisors, there is an decreased overjet and the incisors are usually proclined.
b. The lower incisor edges lie posterior to the cingulum plateau of the upper incisors, there is an increased overjet and the incisors are usually proclined.
What is the definition of a Class II division 2 incisor relationship? a. The lower incisor edges lie anterior to the cingulum plateau of the upper incisors, there is an increased overjet and the upper central incisors are usually proclined. b. The lower incisor edges lie posterior to the cingulum plateau of the upper incisors and the upper central incisors are usually proclined. c. The lower incisor edges lie posterior to the cingulum plateau of the upper incisors, there is an increased overjet and the upper central incisors are usually retroclined. d. The lower incisor edges lie posterior to the cingulum plateau of the upper incisors and the upper central incisors are usually retroclined. e. The lower incisor edges lie posterior to the cingulum plateau of the upper incisors and the upper lateral incisors are usually proclined.
d. The lower incisor edges lie posterior to the cingulum plateau of the upper incisors and the upper central incisors are usually retroclined.
What is the definition of a Class III incisor relationship? a. The lower incisor edges lie anterior to the cingulum plateau of the upper incisors, there is an increased overjet and the incisors are usually proclined. b. The lower incisor edges lie posterior to the cingulum plateau of the upper incisors, there is an increased overjet and the incisors are usually retroclined. c. The lower incisor edges lie posterior to the cingulum plateau of the upper incisors, there is an decreased overjet and the incisors are usually retroclined. d. The lower incisor edges lie posterior to the cingulum plateau of the upper incisors, there is an decreased overjet and the incisors are usually proclined. e. The lower incisor edges lie anterior to the cingulum plateau of the upper incisors, the overjet may be reduced or reversed.
e. The lower incisor edges lie anterior to the cingulum plateau of the upper incisors, the overjet may be reduced or reversed.
What is Orthodontics? a. Is all about straightening teeth b. Involves fixed appliances only c. A way to get rich quickly and retire early d. Treating patients with orthodontic appliances e. Managing the developing occlusion
e. Managing the developing occlusion
Skeletal relationships… a. have some influence on the observed malocclusion but can be safely ignored b. can be one of the most important influences on the observed malocclusion c. should be assessed in 3 dimensions; Antero-posterior, Vertical and Transverse d. have little or no influence on the observed malocclusion and can be safely ignored e. should be assessed in a careful and systematic way
c. should be assessed in 3 dimensions; Antero-posterior, Vertical and Transverse and e. should be assessed in a careful and systematic way
What are the orthodontic treatment options for a patient who has a significant skeletal discrepancy and is still growing? Select one or more: a. Functional appliances b. Headgear c. Facemask therapy with RME d. Accept the malocclusion e. Orthognathic surgery
a. Functional appliances b. Headgear c. Facemask therapy with RME d. Accept the malocclusion
Maxillary Incisors were commonly ectopic. This is true to an extent but which maxillary tooth is more commonly ectopic than the incisor? a. Canine b. Second Premolar c. Third Molar d. First Premolar e. First Molar
a. Canine
Which of the following Orthodontists named the ‘6 Keys to the Occlusion’? a. Anderson b. Andrew c. Angle d. Angel e. Agnew
b. Andrew
