Episodes
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Join me for a summary looking into the increasingly populartopic of paediatric obstructive sleep apnoea, a review of orthodontic treatments available, and how effective they are in this growing field of both medicine and dentistry. This episode is a summary of Alberto Capriglio’s lecture fromthe AAO and Carlos Flores Mir’s lecture at the IOF earlier this year.
OSA - Defined upper airway dysfunction causing complete orpartial airway obstruction during sleep
Sleep = Slow wave sleep – constructive phase of sleep(recuperation of the mind)
· Growth hormones secreted
· Glial cells within brain restored
· Cortical synapses increase in number – Moberget 2019
Outcomes to paediatric patients of SDB: (AASM)
· delays in development, Poor academic performance, Aggressive behaviour,attention- deficit/hyperactivity disorder, , emotional problems in adolescence
First line medical treatment – adenotonsillectomy
· 40% residual OSA
Effect palatal expansion
1. Roof the mouth = base of the nose - Increase innasal airway volume - Reduction in OSA, if obstruction in naso-pharynx,
2. Short term reduction in OSA (not cure AASM)
a. 20% improvement in AHI, 85% of cases Villa 2015
b. 15% got worse by 20%
c. 57.5% residual AHI greater than 1 - notresolution
3. Caprioglio 2019 long term AHI return to initialscores, from 7 to 5 long term
4. Change in metabolism when combined with Vit D3
a. Vit D3 with RME increases reduction in AHI,sustained long term, Caprioglio 2019 AHI 61.9% Vs 35.5% long term
Expansion other outcomes - school performance Bariani 2024
· AJODO – RME improves academic performance –
o BEHAVOUR 1 of 8 parameters improved only foracademic performance - change small 0.68
o COGNITIVE 1 in 8 improve
Mandibular advancement
Move mandible forwards and open space behind the tongue – oropharynx
· Anatomical – increase size of oropharangealairway
· YAnyAn 2019 mandibular advancement for pOSA systematic review: 1.75 AHI reduction (CI) −2.07, −1.44)– modest change
· However long term use required of the paediatric patient
Orofacial features in children with obstructive sleepapnea. Fagundes Flores-Mir 2022
o No craniofacial features specific to pOSA – ANB,
o However medical diagnosis through polysomnographymay under-estimate incidence,
o Broader diagnosis such as snoring, mayover-estimate OSA
AADSM 2024 – consensus statement
· Expansion
o Prevention: No consensus
o Management: No consensus
o Cure: Insufficient
· Mandibular advancement
o Prevention, management, cure – unclear
More about OSA?
To hear more about OSA, please check out the last interviewon orthodontics in interview with Sanjivan Kandasamy, where we had a deep diveinto OSA and where we are in our understanding today from the research
Interviewwith Sanjivan Kandasamy on OSA
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Join me for a summary looking at The Posterior Bolton Discrepancy,a new take on the classic Bolton discrepancy. Wayne Bolton’s analysis has beencritically appraised and the outcome from Patrick Foley and his team has beenthe formation of the posterior Bolton analysis, a new perspective on an establishedtool in orthodontics which seeks to give better insight into the location of toothsize discrepancies. He has also explored through his research the effects ofpremolar extractions and the likely outcomes of compromised occlusal outcomes,and where we should expect to see it within the posterior segment.
Wayne Bolton established the Bolton’s ratio:
· Mesial distal widths of teeth
· Original study 55 well treated cases
· Anterior – ideal 77.2%
· Overall 91.3% - Anterior tooth size discrepancy maybemasked by a compensatory posterior discrepancy
What is the posterior Bolton’s ratio
· Not included in original study
· Formular sum of mandibular 4s, 5s, 6s,/maxillary 4s, 5s, 6s x 100 = 105.27% - data from original Bolton’s study
Ratio confirmed by Mongillo 2021
· N=55 patients ideal outcomes
· Digital casts (from plaster)
· Posterior ratio 105.77% +/- 1.99% VsBolton’s data of 105.27%
The effect of 4 premolar extractions on the posteriorBolton ratio
Study: Mongillo 2021 (extraction of all 4s) Holton 2023 (extractionof upper 4s, lower 5s)
· Posterior Bolton increases 107% +/- 2.23%(or U4s and L5s 106.52 +/- 2.52%), ideal digital removal of teeth
· Observed Bolton’s was 110.48 % = 3.18% above Bolton’s ideal
· Space of 1.1mm – 1.28mm remains in mandible whenideal arch – only 1 patient did not have space
Clinical options
i. compromise occlusion
1. slightly class 3 molar and class 1 canine
2. class 1 molar and slightly class 2 canine
ii. IPR upper arch
iii. Bonding
· Anterior and posterior Bolton may be valuable indiagnosis and prediction than an overall Bolton
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Missing episodes?
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Join me for a look into a recent digital innovation withinorthodontics, Lightforce. I explore how the 3D printedlabial bracket system works, the features and what the proposed advantages. Recentresearchexploring the advantages of Lightforce is discussed as well as my comparison toother digital innovations within orthodontic appliances.
What is Lightforce
· Manufacturing: 3D printed brackets Cad/Cam
· Material: ceramic polycrystalline labial
· Planning: Digital planning using Lightplan,visualisation of the outcome, alter both tooth position and bracket position,individualise prescription per bracket as a result of planned movements
· Flexibility in positioning: Brackets do not have to be in the Facial Axisof the Clinical Crown, through altering the base thickness, the resultingmoment can be achieved through the center of resistance
· Torque expression is independent of the vertical position, for the same reasons
· 0.018", 0.020", and 0.022",including combinations
Stages
1. Submit records
2. Digital planning using lightplan, visualisationof the outcome,
3. Case approval
4. Indirect bonding tray – light-Tray, with bracketsin situ
Other advantages
· Accuracy of 3D printed slot
· Adapted base, less adhesive
· Minitubes, biteturbos
What are the proposed advantages and claims around Lightforcewith evidence
1. Shorter duration of treatment due to precision
a. JCO 2024 Wheeler 2024 Retropsectice study, 900 lightforcescases and over 300 conventional cases, 30%shorter and 30% fewer appointments. significant floors, with a lack of outcomemeasure and matching of controls
Proposed advantages and claims around Lightforce ithoutevidence
2. Reduced complications white spot lesions, dehiscencesand root resorption as relate to duration
3. Remove issue of compliance or biomechanics as limitationsto treatment outcomes
4. Saving Doctors time and money, removerepositions
5. Reduce or eliminate wire bends
What are my thoughts?
· Labial fixed appliances are catching up withaligners and lingual appliances
· New possibilities of varying biomechanics, slotsize, bracket position and customised prescription
· Presence of Lighforce features within otherappliances:
o Customised brackets Insignia / Incognito
o Digital planning: aligners, Insignia
· No customisation of archwires with Lightforce
· Not sure how Lightforce would reduce appointmentintervals, ligation is conventional ligation through elastomeric modules, withplastic deformation
Papers and videos on Lightforce
https://www.jco-online.com/media/42415/2023_09_500_waldman.pdf
JCO retrospective study
https://www.jco-online.com/media/43897/2024_05_273_wheeler.pdf
Youtube videos from Lightforce company, Alfred Griffin
https://www.youtube.com/watch?v=zSNkYVgZ69I&t=2s&ab_channel=People%2BPractice
Disclaimer
The podcast is opinion and may not be 100% accurate orrepresentative of the lecture / speaker, the podcast is not endorsed by aninstitute or the speaker and is the independent work of Farooq Ahmed and theOrthodontics in Summary team. It is not intended to over-ride or replace therequirement clinicians have in being familiar with the relevant training andguidelines for the treatment they provide.
Contributions
Contents and editing
Farooq Ahmed
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Join me for a podcast summary looking at the effects ofaligners when expansion occurs. In this podcast we will explore if bone lossoccurs with expansion and why bone loss doesn’t necessarily cause recession. Thepodcast is based on the lecture and research by Greg Huang presented at this year’sAAO, and includes some more recent research on the topic
PICO
Population adults, 22 maxillary arches, 20 mandibular arches
Intervention – expansion with aligners, average 3.7mm
Control – minimal expansion, average 0.6mm
Outcome – bone height and width from CBCT
What was the bone loss?
Maxilla
· Minimal bone loss
· Minimal bone height and width change
Mandibular
· Significant bone loss
· 1.5mm height mandibular centrals
· 1.4mm height premolars
What movement took place of the incisors?
Maxilla
· Little change in bucco-lingual inclination
Mandibular
· Labial and buccal tipping increased
What were the overall changes?
Dental changes
· 3-4mm of expansion
· Mainly atpremolars
· Mainly buccal tipping, not bodily movement
· Lower incisors procline
Similar bone loss with aligners expansion from other studies,Zhang 2023 , Allahham 2023
Should CBCT’s debate within the literature regarding voxelsize of a CBCT and false negatives. Accuracy of alveolar height CBCT 2019 Yuan Li BAsystematic review showed
· CBCT Vs skulls/patients
· Bone height 0.03mm
· Bone width 0.11mm
My thoughts: no difference in cbct and gold standard,however the measurements were all of large structures, not bone height orthickness of less than the voxel size
Predict bone loss
· Upper arch no predictors as limited changes
· Lower arch, same as for fixed appliances, butthe quantity was missing
o Proclination
o Expansion
o Buccal expansion and tipping
Systematic review of orthodontics 48 articles deLlano-Pérula 2023
· Proclination
· Less keratinised tissue
· Thin biotype
· Prior recession
· Crossbite
· Previous recession
· Age
Does bone loss = gingival recession?
· Not generally found from Greg’s study
· When significant bone loss of 3mm, far less than3mm gingival recession
Significant retraction of upper incisors and intrusion Kim2024. Loss of Palatal bone however in retention palatal bone recovered
Hypothesis
· If PDL and periosteum are maintained epithelium is maintained
· If the root moves back into the bone, the bonerecovers – as PDL and periosteum osteogenic, and tension generated between PDLand periosteum
· PDL-periosteum hypothesis – proposed by GregHuang
What I liked about Greg’s lecture was that he started withdeclaring his conflict of interest as an academic, both the royalties hereceives for his books as well as research funding, which was great to hear anda trend I hope continues. Acknowledged the hard work of the research lead, his traineeand the time-consuming process of orientatingCBCT slices of 1000s of images
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“Airways are like TMD controversy on steroids”
“it amazes me we still think we can grow mandibles”
“We have an appliance (expansion) and are trying to fit it into a diagnosis”
“it is unethical to call yourself an airway orthodontist”
Sanjivan describes why there is controversy inairways and orthodontics, where the research stands on treatment with expansionand mandibular advancement, can mouth breathing cause adverse development, theeffects of extractions on the airway, as well as ethics within current practiceof airway orthodontics.
Click on the link below to view previous episodes, to refresh topics,pick up tricks and stay up to date.
YouTube
https://youtu.be/m2NIp1XhnxQ
#orthodontics
#farooqahmed
#sanjivankandasamy
#westaustralianorthodontics
#airwayorthodontics
#airway
#OSA
#SDB
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Join me for a summary exploring an innovation of the use of bone-anchored plates in class 2 correction. This was a clinically novel idea presented by Hugo De Clerck, who has been an innovator in the use of bone-anchored plates and has published seminal papers on the topic for class 3 treatment.Hugo explores the use of bone-anchored plates in the mandible, combined with a Herbst appliance. He presents his data of 90 patients treated in Brussels by his research team.PROTOCOLCustomised bone anchored plates in lower anterior mandible – digitally designed per patient with surgical guideTransmucosal between lower canine and 1st premolarHerbst: modified to attach from upper 1st molar to the lower bone anchored platesProcline upper incisors prior to fitting Bone anchored-HerbstExpansion of the upper arch2-3 modifications to Herbst piston to lengthen during treatmentDuration 10 monthsHOW DOES IT WORKGrowth of the mandibular body: mainly, bone modelling. Average growth 5-7mm, whereas conventional herbst 2-2.5mm of chin projection. New growth of bone as ramus moves backwards, resulting in lengthening of the mandibleForce generation: in similar to the conventional functional appliance, with contraction of medial and lateral pterygoid and stretching of the suprahyoid and temporalis muscleLower incisor proclination: No lower incisor proclination: There is a distal force on the mandibular dentition instead of a forward force from conventional functional appliances, due to the appliance attaching to the mandibular body, not the dentitionCondylar displacement: Longer duration, of up to 10 months which results in stimulation of growth of the body of the mandible, conventionally this stops with a herbst as the lower incisors procaine, resulting in only 2 months of condylar displacement and therefore less stimulation of growthGlenoid fossa remodelling. The glenoid fossa remodelled in a forwards direction, however it was small and unpredictable, with some posterior remodellingRotation of mandible – similar to the conventional functional appliance, a posterior rotation reduces the effects, anterior rotation enhances, for every 1 degree 1.1mm increase projection. Achieve via expansion and removable applianceUpper molar distalisation: Hugo saw this as unfafourable and advised lengthening the herbst piston to reduce upper molar distalisation, therefore maximising mandibular lengthening Age 13-15Not possible with miniscrews, due to the quantity of forceBreakages of Herbst still occurIs growth maintained long term – unable to stateNo control as requirement for cbct of untreated patients. ContributionsContents: Farooq AhmedEdited and produced: Farooq Ahmed
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Join me for a summary looking intodifficult movements with aligners, why they are difficult, and a protocolderived from research on how to manage tooth movements with aligners. Thislecture was given by Bill Layman at this year’s AAO, where he describes maxillaryincisor extrusion, posterior intrusion, and controlled expansion.
Introduction
· Rate of refinement: 2.5 perpatient Kravitz 2022
· 41% of aligner cases 3refinements +
· Switch to fixed appliances fromaligners 1 in 6 Kravitz 2022
Staging and synergistic movements can reducerefinement rates
Incisor extrusion
Why is Incisor extrusion difficult?
· Lack of undercut
· Sqeeze teeth to engage, creatingopposite effect due to V shape of a tooth – leading to loss of retention of thealigner
· Interproximal binding through verticalcontact point overlap or slipped contact points and a closed system of aligners
Incisor extrusion staging steps:
1. Create undercut: Horizontalattachments are most effective, regardless of design Groody 2023
2. Create 0.1mm between teeth torelieve interproximal binding
3. First procline the incisors toincrease surface contact
4. Then Extrude and retract
Posterior intrusion
Why is it difficult?
· Multiple teeth and lack of anchorage,through anterior teeth
· Crowns tip mesially duringintrusion as an unwanted effect
· What happens when we intrude:
o Mesial tipping of posteriorteeth Fan 2022 Finite element
o Buccal and palatal attachments= less tipping buccal or lingual
How to improve posterior intrusion
· Sequential intrusion – 1stpremolars
· Tip posterior teeth 5-10 degreesdistally
· Horizontal attachment buccal /palatal
· Consider attachment lingualUpper molars
· Sequential intrusion
· TADs not always needed, 5200 timesbite on hard surface, enables posterior intrusion through masticatory forces
Controlled expansion
Why is it difficult
· Aligners tip teeth buccally =creates occlusal interferences
· Lack of rigidity of tray toexert forces = straight finish trays increase rigidity
· Attempting to correct skeletalproblems with dental solution
· Greatest expansion in the premolarregion
· Expansion from the researchshowed progressive less posterior expansion
o Molars expand less due toanchorage loss
· Expansion through tipping
How to improve posterior intrusion
· Plan around premolar expansion
· Expect 70% in premolar region,55% molar and 46% canine
· Overcorrection of canines 1.7mm(premolar region 3.4mm) Zhou 2020
· Maximum expansion seen is 4mm
Conclusion:
· Incisor extrusion: proclineteeth with attachment, then extrude and retract
o Include iPR
· Posterior intrusion: Start withpremolars and sequentially intrude posterior teeth
o Add distal tip
· Controlled expansion: Effectivein premolar region
o Plan with overcorrection
Jay Bowman
· “If you don’t build-inovercorrections you can’t get corrections”
· “there many things that needimprovement at the end that aren’t hard to do if start treatment with theovercorrections in mind”
Contributions
Contents:Shanyah Kapour
Editedand produced: Farooq Ahmed
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Join me for asummary looking at fixed versus removable functional appliances. This podcastsheds light on recent research comparing the main two types of functionalappliances, which appliance offers the most advantages, and what patients thinkabout the two appliance types. This was a lecture given by Ama Johal at lastyear’s British Orthodontic Conference, where the most recent evidence carriedout by his PhD student Moaiyad Pacha.
Moaiyad Pacha’sRCT 2023 – received Dewel 2024 clinical research award
· Hanks Herbst Vs Modified Twinblock
o Rollo bands
o Expansion
o No fixed appliances
o Incremental advancement – no evidence to supportbut patient-centred
· Overjet correction: More effective Herbstat 7mm Vs 5.8mm Twinblock ,
· Molar and skeletal changes: no difference
o Twinblock = greater residual overjet aftertreatment p=0.2
· Dental changes: Herbst advance lowerincisor greater 3mm Vs 1mm
· Failure to complete: 17% Herbst Vs 37%twin block
o 3 times greater likelihood of discontinuetreatment OR 2.8
· Treatment duration: longer with Twinblock1.5 months 8.8 Vs 10.3, and quicker rate of correction with Herbst
· Chairside time : Greater than Twinblock2.7 hours longer, 7.6 Vs 4.9
· Emergency appointments greater with HanksHerbst 2.7 Vs 0.3
o Herbst mainly
· Severe complications = same 0.5
o Severe complications – previously defined asinvolving lab work or break in appliance wear from Pasha’s SR 2020
Advantage of Hanks Herbst
· Greater completion of treatment, 3 times lesslikely to discontinue
· Quicker rate of correction, shorter duration,
Disadvantages
· Greater chairside time of nearly 3 hours
· Greater emergency appointments, each patientneeding 2-3 emergency appointments
Qualitative
· Both appliances – very negative to QoL and dailylife
· Aesthetic and self-image – worse with Twinblock
· Patient preference – Herbst
o Due to non-compliance and likely to get to theend
· Positive Twinblock is flexible and easier to eat
Conclusion was profound
· Patients prefer Herbst, based on aesthetics,self image and non-compliance
· Clinicians are likely to prefer Twinblock,quicker, easier, less emergencies
Time to reconsider, and having both options, as well as bothdiscussing of clinician Vs patient preferences, should decide which appliance
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Join me for a summary podcast exploring the topic of white spot lesions, and up-to-dateresearch looking at how to manage lesions when they occur, when the right timeis to treat the patient, and what minimally evasive options can be used in clinic. This was an excellent lecturefrom Gayle Glenn earlier this year at the AAO winter meeting.
Four treatmentoptions are discussed, Fluoride, CPPACP (Mi paste), resin infiltrate andmicroabrasion.
Whitespotlesion background WSL
Definition - subsurface deminieralization,intact outer layer, 1st sign of carious lesionsRemineralisation– no additional agents
Most rapidrepair first 6 weeks without use of additional agents
· Upto 6 months spontaneous improvement with good oral hygiene
· Recommend3-6 months monitor after debond: BEFOREconsider additional treatment
Fluoride
· Decreaseenamel dissolution
· Increasereminerazation
· Formationof fluorapatite
· Products
o Fl varnishreduce WSL occuring by 44%:
§ require plaque removal and wire removal
§ Not often used in clinical practice and requiresrepeat application
· TREATMENTWSL
o Fluoride low dose (toothpaste)
o High Fluoride – hyperminerasied surface layerforms = seal off subsurface layer which remains demineralized. Bishara 2008
Resin infiltration Gray 2002
· Remove outer hypomineralised area with 15% HFL
o Infiltrate with low viscosity
o Improves aesthetics
o Arrest lesion – however some demineralisationmay remain
o Lack long-term evidence
o Most effective in research (RR:121.50, 95%CI:51.45-191.55 Jiang 2023)
MI paste (CPPACP) Frencken 2012
· Milk protein derived
· Stabilizes Ca PO4 – ideal of for formed WSL
· Creates Ca PO4 reservoir around bracket
· Applied:
o Brush above and below bracket or finger
o Distributed by the tongue
o Can be swallowed
o Avoid eat and drink 30-60 minutes
· Effectiveness for reminersation
o Evidence unclear – conflicting sustematicreviews AlBukaiki 2023 no difference, same year Jiang 2023, it is effective, however exceptionally large rangeof values (RR:49.69, 95%CI: 0.87-98.51 and although RCTs, limited to assessingpremolars only and different methods of assessment and duration of treatment.
· TREATMENT FOR WSL
o Wait 3-6 months following removal of braces
o In retainer 3-5 minutes
o Rinse out
o Nothing to eat 30-60 minutes
Microabrasion
· Combination of acid and abrasive particles
· Burinsh into enamel with slow speed handpiece
· opalustre = 6% HCL + silica (low particlesize, lower concentration with larger particle size than prophy paste = 12-160 particle size 1986 Krol)
o 1 mm size of use
o Burnished in using a polishing cup and slowhandpiece
o 1 minute
· Not widely accepted
o Partly due to variations in protocol
o Use of rubber dam
· Microabrasion and CPP-ACP proposed idea Ardu2007
2022 Lammert
· CPP-ACP both sides, with half of mouth alsoreceiving 1 visit of microabrasion
· After 6 months post debonding
· Evaluate and repeat up to 8 times
· Results
o Mi paste group 9.3-8.1 size of lesion –statistically significant
o Microabrasion and Mi paste group
§ 13.2 – 4.3and reduce to 2.1
· Most improvement immediate after microabrasion
o Compared difference of size of the initiallesion
§ 5.5 xreduction in CPPACP
§ 7.4 Xreduction in microabrasion
Clinical implication
· Microabrasion = significant clinical time
o Up to 8 minutes per tooth, can be up to 1 hour
o Therefore clinical application
§ Perhapsisolated 1 or 2 teeth
Conclusions:
1. Patientswith WSL are usually not great compliers, giving additional products whichrequire significant compliance, is practising research in isolation.
2. Microabrasiontakes nearly 1 hour, role in clinical practice limited to isolated areas
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Join me for a summary exploring bullying and itsrelationship with malocclusion, with a contemporary review of evidence showingthe psychological effects various malocclusions can cause young people. Thispodcast is a summary of Andrew DiBiase’s lecture last year at the BritishOrthodontic Conference. Andrew’s research explores what factors moderatebullying, and what factors can be protective against bullying.
Introduction
· Nearly 1 in 3 patients report teasing or fear ofteasing as a motivating factor for orthodontic treatment Bauss 2023 AJODO
· 1 in 7 patients attending our clinics arebullied Seehra et al., 2011
· Most upsetting feature of bullying teeth 60.7%Shaw
· 13, 387 teenagers 25% report bullying
o Around 7% related to teeth
Definition of bullying: Olweus 1984
· Unprovoked and sustained campaign of aggression,towards someone in order to hurt them
· Student exposed repeatedly to negative action onthe part of one or more students
o Harm, imbalance of power, organised, repetitive,harm experienced
Who gets bullied and how?
· Younger more – 10 year olds 22%, 15 year olds 7%
· Girls are greater than boys by 5%
· Boys low athletic competence
o Judged on homour as well Langlois 2000
· Girls appearance
o We do judge girls on physical appearance Langlois2000
o 80% verbal - Cyber bullying – doest stop at theschool gate
Consequences of bullying
· Short term and long term effects
o Poorer academic performance
o Crime
o Self harm
§ 26% within young population and teeth occupyingthe reason in 1 in 5 young people Bitor 2022 AJODO
o Low self esteem
o Structural changes, medulla – related to fear(peer victimisation and its impact on adolescent brain)
What features are more likely to result in bullyingDibiase, Jad Seehra 2014
· Greater rate of bullying
· 2 div 1: 18%
· Increased overjet 16% Tristão SR 2020
· Deep overbite
· Missing teeth, anterior spacing
· IOTN AC 9 and 10
· Regression – younger worse
· Low athletic competence p 0.019
Conclusions
· Relationship between bullying and severemalocclusion
· Schoolchildren who report being bothered bytheir teeth report being lonelier at school and lower self-esteem
· Malocclusion has a greater impact on femalesthan males
· Malocclusion and peer relations is moderated byself-esteem in girls, but not boys
· Good peer relations protect against the negativeimpact of malocclusion in girls with low or average self-esteem
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Orthodontics and TMD, what is the role of orthodontics?
“if you give a splint, it will not cure the TMD”
“It depends on the adaptability of the patient”
“The role of the patient in the treatment is very, very important”
Roxana describes her journey into TMD and orthodontics, what led her to attend courses worldwide and also set up her own course on TMD.
Roxana describes what has created the controversy in TMD management, and answers recent questions from the literature of the role of both orthodontics and splints in TMD management
To book onto Dr Roxana Petcu’s courses please visit www.lazarlearning.ro/cursuri/ or roxanapetcu_ (I have no financial interest)
Click on the link below to view previous episodes, to refresh topics, pick up tricks and stay up to date.
Please like and subscribe if you find it useful!
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Does whitening have a role in orthodontics? A popular cosmetic procedure which 1 in 4 adults partake in, and was proposed recently at a conference as part of finishing in orthodontics. So this podcast reviews whitening as a topic and the latest evidence in combining whitening with aligners.
Reminder the podcast is an opinion piece and is the independent work of myself and the orthodontics in summary team.
24% of adults have whitening their teeth (dentalhealth.org)
How does it work:
Bleaching is the chemical changing of darker staining on teeth termed chromogens, with the active ingredient hydrogen peroxide.
Hydrogen peroxide reacts to oxidize the chromogen, which becomes a lighter colored compound.
Hydrogen Peroxide is not a stable chemical, so Carbamide peroxide is used, which roughly breaks down to 1/3 H2O2 when mixed with water.
Hydrogen Peroxide UK limit 6%, or Carbamide peroxide 16% is used, USA, greater concentrations are used with 10% hydrogen peroxide for at home whitening, and 35% hydrogen peroxide for in office bleaching.
Children
UK guidelines GDC 2014 – no bleaching until 18, unless purpose of treating or preventing disease.’
USA: The AAPD 2023 s Safe and effective for whitening discolored teeth of children and adolescents. Avoid full-arch bleaching mixed dentition and primary dentitions
Risks
Sensitivity -
about 80% of patient’s experience sensitivity
Tooth sensitivity usually occurs at the time of treatment and can last several days
Upper lateral incisors – greatest sensitivity
Directly correlated with concentration
Greater intensity if tooth was restored Bonafe 2013
Gingival irritation
gingival irritation begins within a day of the treatment and can also last several days
Susceptibility to demineralisation
Suggested surface demineralization occurs as the pH of the whitening agent are acidic and hydrogen ions affect the enamel crystals,
No difference when using manufacturers protocols including 35% H202 Tompkins 2014
However aggressive whitening: excessive use of in office whitening Shi 2012
How long does the whitening last
Duration of correction, depends on lifestyle, with smoking and coffee reducing the correction. Expected 6-12 months of stable colour change. Wiegand 2008
Aligners
Bleaching tray is different – reservoir for bleach, 1 or 1.5mm soft ethylene-vinyl acetate (EVA), Straight cut 2mm beyond gingiva or scalloped, with 2 mm extension onto the gingiva giving a better seal and greater patient comfort. Dosage dots to limit application beyond 2mm
Aligners
Usually gingival bevelled, but as effective as bleaching trays, Levrini 2020 improvement of 3.5 shades on average Seleem 2021
tooth sensitivity and gingival irritation does not disrupt of treatment 16% Carbamide peroxide Oliverio 2019, Levrini 2020
2 mm thick layer of gel is advised at incisal or facial central surface of the aligner
Bleaching with attachments present, when bleaching complete attachments removed:
hydrogen peroxide diffuses through spaces between enamel prisms
The composite attachment was thought to affect pigment infiltration, however with enamel polishing after composite removal, color equalization occurs without discrepancies Staley 2004
Minimal change to aligner structure Oliverio 2019
Retainers as bleaching trays?
Use of 0.8mm Zendura, no resivoir, effective bleaching with marked or extremely marked improvement in 78% of cases with 10% Carbamide peroxide, however but this changed the VFRs’ biomechanical properties, decrease in tensile strength and an increase in hardness and internal roughness, unclear what the medium and long term effects are .Jin 2024
Bond strength
By Bleaching a tooth there is enamel bond strength reduction by 25 % Miguel 2006
Wait 2 weeks after bleaching for aligner attachment placement.
Bonded retainer has not been researched
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Join me for a summaryof direct to print aligners. This lecture explores the application of a relativelynew resin material which can be used for aligner fabrication, without the needof a 3D printed model. The lecture was given by Simon Graf who expertlycompared the differences between conventional and direct to print aligners, aswell as the clinical application of specific features of direct to printaligners.
Limitations ofcurrent aligner material:
1. Only smallundercuts
2. Limitedaligner thickness to sheet thickness / no selective thickness
3. During themanufacturing process material can get thinner or thicker depending on heat distributionand stretch, 54% change in thickness of the aligner Lee 2022
4. Plasticand resin waste, (122 million aligners and models in 2022 Slaymaker 2024)
Advantages of directto print aligners
· Select thickness, 0.5-0.7mm, conventionalaligners 0.75mm+
· Gingival margin
· Dentist incharge of design, not company
Manufacturing stepsof Direct to Print aligners (Tera Harz ‘Graphy’)
1. 3D printingof resin aligner
2. Centrifuge:Spin remove excess resin
3. UV Lightcure in Nitrogen chamber
4. Washedtwice, hot distilled water
Characteristics ofDirect to print aligners
· Greater accuracy: (Zendura, EssixAce and DTP were compared and DTP were 20-30% more accurate Koenig 2022)
· Less with DTP (Hertan 2022)
o DTP 50%less still (2.59 Vs 5.26 N)
o DTP Lessforce as strain increases
Shape memory effect
· DTP Polymer chains crosslinked, not case in conventional aligners
o The shape recovers in DTP whenstrain is removed, which does not occur to the same degree in conventional alignersLee 2022
o Accelerated by placing in water
Unknowns
· How effective shape memory is remains unclear
· Cytotoxicity – not enough data, although manufacturerprotocols, lack of studies
· Changing thickness, unclear how much of adifference in force it makes
Clinical points
Teeth extrusion
Lateral incisors
· Difficult to do with conventional aligners,
· Create ‘wedging’ gingival pressure columns tosqueeze the teeth to cause an extrusive force.
Elastic Hookswithout loss of force delivery on single tooth
· Hook printed into aligner with DTP, instead of cutout which alters the force of the aligner instantly, maintain tooth control
· Tip aligners and elastics: Still add attachmentto tooth to prevent aligner displacing
Mandibular advancement
· Problem of mandibular advancement with aligners
o Wings softand not maintaining the AP position
o Hard blockmany breakages
· DTP choice of thickness of block
Bite ramps
Conventional biteramps: limited length and often too short
DTP no limit to sizeand thickness, and can be designed to not contact upper palatal surfaces, maintainingfull tooth control
In the Transverse
o Palatalcoverage can be added as feature, similar to a TPA
o Stillbeing researched how much force can be delivered with palatal coverage
Concluding statement
Enjoy the variabilityof direct printed aligners.
Contributions
Contents:Abdallah Sharafeldin
Editedand produced: Farooq Ahmed
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Join me for a summary looking at gingival recession in orthodontics, and whether it is detrimental or beneficial. This lecture was given by James Andrews, he explored the effect of orthodontics on the periodontium, an area under increasing interest within aesthetics to achieve the ideal ‘pink aesthetics’ with the increasing adult population receiving orthodontic treatment. His lecture was based on, is orthodontics good or bad for the gingiva?
What is the starting point ?
Increase in adult orthodontics from 1970 by 800%
50% of adults have some element of periodontal disease
Untreated adult population 51% dehiscence 37% areas of fenestration Evangelista 2010
Facial type and bone morphology Tunis 2021
Dolichocephalic = narrow alveolus and elongated to compensate for vertical growth
Brachycephalic = larger alveolus
Dolichocephalic - Red flag patients
Tooth movement:
What happens when teeth move buccally?
facial tooth movement Wennström 1996
Reduced bucco lingual width
Therefore, reduced free gingiva
Increased risk only if tooth is moved out of the alveolar housing
What type of movement
Tipping (uncontrolled) increase likelihood of recession Condo 2017
Proclination causes recession, but inconclusive
Thickness more relevant than final inclination Yared 2006
How to decide what to do?
WALA line – Will Andrews Larry Andrews ridge Andrews 2000
Limit of labial bone – shape is coincident with the mucogingival junction, coincident with centre of resistance
Upper incisors – located anterior 1/3 of alveolus
Mandibular incisors – cantered within the alveolus
Gingival recession did not increase in treatment orthodontic population with segmental mechanics Melsen 2005
Aligners any different?
Association between non-extraction clear aligner therapy and alveolar bone deficiency and fenestration
Presence of both fenestration and dehiscence
What do we do to correct extra-alveolar teeth?
If teeth pushed outside of cortical plate then retracted, what happens
Monkey – moved teeth outside of bone for 8 months, then reposition within bone with appliances = repair bony dehiscence and fenestration
Morten Laursen and Melsen 12 consecutive patients 2020
Teeth moved towards the centre of the cortical plate = improvement in gingival height of depth decrease of 23%, the width with 38%
Intrusion
Use of intrusion arch increases the thickness of the periodontal fibres 0.7 to 2.3 mm Melsen 1988
Gingival graft when to move teeth
Free gingival graft – 6 weeks
Connective tissue graft – 12 weeks
“Diagnose and treat each tooth no miracles shortcuts for good orthodontics” Peck 2017
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Join me for a summary looking at miniscrews, looking atwhere the answer to successful TAD placement lies, in research or clinicalpractice. The reasons for higher failure rates than others with TADs wasexplored through 3 key factors; insertion torque, site selection and rootproximity. Evaluation of both scientific and clinical processes were describedby Sebastian Baumgartel at the British Orthodontic Conference, as theNorthcroft lecture.
Is torque a factor in TAD success?
Torque study – compression during insertion Motoyoshi 2006
· High torque – 60%
· Low torque = 72%
· Medium torque – 92%
Understanding
· Low torque = low compression, low primarystability - early failure as not engagement with screw
· High torque = high compression, early success,but greater resorption after insertion, remodelling results in a resorptionprocess
· Medium = best of both = sufficient compressionfor primary stability, not high enough to cause resorption remodelling
Ideal
· Ideal torque range – 10 Ncm Shantavasinkal 2016
o Study of buccal tads
· Sebastian’s empirical experience between10-25Ncm depending on site
Rules:
· Aim for medium torque
· Target 10Ncm
· Exceed 10Ncm on palate acceptable
What is the best site for TAD insertion?
Keratinised gingiva
· Evidence - states no difference Lim 2009, Chen 2008, Park 2006, Cheng 2004
· Non Keratlised – depends on mobile or nonmobile, with non-mobile higher success rate Viwattanatipa 2009
· 2mm apical to muco-gingival junction
o zoneof opportunity
Target zones and site
o No roots
o Consistent cortical bone
o More tolerant to higher torque
o Attached gingiva with low mobile mucosa
Is there ideal bone?
· = ifideal torque = ideal cortical plate thickness
§ 1-1.5mm cortical plate thickness
· CBCT can be overkill, using research sites foraverage sites
Ideal site:
– 1st premolar region (transverse) Sebastian 2009
– 2 mm away from mid-palatal suture
o = creates ideal zone ‘Mx1’
Evidence of site selection success
· 98% Vs buccal 71% Houfar 2017
· 84% Trainee success Sebastian 2020
· Success of Sebastian anterior palate 100%, maxillarybuccal lowest 85%
Does root proximity influence TAD success?
· Not just contact with roots, but proximity toroot also causes failure Kuroda 2007, Asschericks 2008, Chen 2008
Understanding
o Increase root and PDL proximity = bone stress increases = increase bone turnover= increase failure of TAD
· 4mm interradicular distance needed (depending onsize of tad) to achieve 1 mm clearance from roots
· Most buccal sites have less than 4mm (resolvethrough diverging roots, or sites with no roots)
What happens if TADs fail and we try again?
– Secondary insertion success
o 58% (reduced by 33%) Park 2006
o 44.2% (reduced by 36%) Uesugi 2017
o 58.1% buccal (reduced by 21%), 88.9% palatal(increased by 4%) Uesugi 2018
§ Uesugi 2018 showed buccal failure increases forsecondary insertion, but palatal insertion increases success
For more education see Sebastian’s TAD course:
https://tadchallenge.com/tad-certification-course
I have no financial interest
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Join me for a summary of Tommaso’s lecture on aligner treatment, exploring questions on the use of aligners. Tommaso described how compliant patients are with the use of aligners, who is more likely to wear aligners well and methods to increase compliance. He critically reviewed the use of attachments, and revealed aligner deformation and staging as key areas of treatment. This podcast is a summary of the WFO online webinar from November patient compliance, biomechanics , rotation, distalisation and intrusion
Patient ComplianceSample of over 200 patients treated with aligners under remote monitoring, Thirumoorthy 2021:
36% of the sample was fully compliant
25% has poor compliance
1st time Ortho patients are more compliant
Conclusion: early detect non compliant patients with remote monitoring
Patient factors which vary compliance of removable appliances Fleming 2019
The study came with some recommendations:
Effective communication with our patients, with visual aid, pictures or movies.
Using of tracking sensor included in the device
Using some reminding tools – remote monitoringBiomechanics and material properties.Distalisation class 2Incisors intrusionConclusion
We need to consider the lines of forces and aligner deformation not only on the attachments
Any malocclusion that can be corrected by tipping has better predictability
Add less activation Per aligner (to help flattening the steep decline in force over time and create consistent and continuous force system)
Attachment driven mechanics are not always effective, aligner Activation is more effective
Graphy is the trending technology in aligner activation
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Join me for a podcast summary looking at the grey topic oflower third molar management. The podcast explores the different guidelines of removal,factors for consideration for removal as well as the effect orthodontics canhave on third molar pathology. The lecture was given by Flavia Artese at thisyear’s British Orthodontic Conference in my city London.
Flavia Artese began with asking the clincal question weface, what would you do with an impacted 3rd molar?
Difference in international practice
· UK NICE guidelines 2000: Surgical removal ofimpacted third molars should be limited to patients with evidence of pathology
· AAOMS White paper USA 2016: currently or likelyto be non-functional associated with disease or at a high risk of developingdisease
What factors in decision making
1. Eruption path
· Mandible = mesial, whereas Maxilla = distal
o Rate of impaction Mandible 25%, maxilla 14%Worthington 2016
2. Mechanism of tooth eruption – explained byFrazier-Bowers
· A pathway created by the dental follicle
o Triggers eruption of intraosseous eruption
o Genetic control of cell differentiation indental follicle
§ Requires root elongation, vascular pressure andDL ise 2008
Orthodontic influence = SPACE
· Decrease with distal movement of posterior teeth
o Distalisation, elastics
§ Kim 2014 = limit of lower molar distalisation
§ 35% of cases already have contact with lingualcortical plate
· Increase through mesial movement
o 80% of 3rd molars erupted in premolarextraction cases Kim 2003
o Increase in retromolar area
o 2nd molars – removal of guidance =unpredictable alignment of 3rd molars, tipped, therefore will likelyrequire orthodontic alignment Gooris 1990
§ Flavia suggested if 7s impacted, removal of 8sand 2nd molar uprighting, as no delay until full root development
Prediction method
· Mandibular morphology
o Longer the mandible = greater chance of 3rdmolar eruption: Begtrub 2012
· Retromolar space
o OPG - size of crown and space available: If space greater then size of thetooth = 75% eruption, if less space available than the tooth size = 75% ofimpaction Olive
Prediction of orthodontists and surgeons Bastos 2016
· Orthodontists 38% extract
· Surgeons 50% extract
· Surgeons extract more
o Surgical morbidly 10% Yamada 2022
o Greater pathology: 82% when erupted, 74% in softtissue, bone 33%
Surveillance protocol
· No complaints from patients
Fully erupted
· No consensus of protocol pathology
Review of guidelines Gadiwalla 2021
Only 2guidelines were recommended , RCS and SIGN
· Recommended guidelines
Conclusion
· Limited evidence
· Orthodontists can influence the space
· If second molars require extraction, willrequire time to erupt as well as
· CBCT should be used for diagnosis
· Refer to oral surgeon for assessment ofdifficulty in removal
Please join Flavia Artese at the 2025 InternationalOrthodontic Conference in Rio De Janeiro
Contributions
Contents: AbdAllah Sharafeldin
Contents edited andproduced: Farooq Ahmed
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Join me for a podcast exploring the limits oforthodontic tooth movement. This podcast is a summary of two intriguinglectures, by Dr Yanqi Yang and Carlos Flores Mir from this year’s InternationalOrthodontic Symposium by the IOF. This podcast explore the anatomical andperiodontal boundaries of orthodontic tooth movement
Anatomical boundary
· Distalisation: Alveolar boundary lowermolar distalization
· Horizontal: Atrophic ridge.
· Vertical: Maxillary sinus
boundary for lower molar distalization.
o Coronal level: Anterior border ofmandibular ramus
o Apex level: lingual plate
o Variable – distance from secondmolar distal root and inner lingual cortex
§ Favourable Class 3 greater retromolarspace, class 2 least Fan 2022
§ Unfavourable High angle haveshorter distance Kim 2021, Victoria 2022
Side effects of lower molar distalisation
o Mainly tipping
o Distalisation achieved at apicallevel approximately 1mm AJODO 2016
o Lingual plate contact 1/3 of cases Kimet al 2014
Horizontal movement: atrophic ridge
· Change in width and height ofextraction site
o Loss of 40-60% width and heightPagni 2012
§ Width 3.79mm Tao 2012
§ Height 1.24mm Tao 2012
o Mostly within 6 months Schrepp 2003
· Changes when orthodontic toothmovement into atrophic edentulous site
o Increase bone height 2.2-5.2mm,duration 24 months Elif 2004
o Increase in width 0.8-1.6mmStokland 2011
o Greater height increase buccally,less lingually Dos Santos 2017
· Side effects
o Root resorption – lateral
§ 0.7mm
o Dehiscence
§ Slight in all cases, thinning ofalveolar bone Patricia dos Santos 2017
o Reduced bone height compared tonon-edentious area
Vertical:
· Maxillary sinus prevent toothmovement?
o Increased tipping, slower rate of toothmovement
· Side effects
o Mild increase in RR
o No difference in relapse, vitalityor periodontal differences
o 6 buccal roots closest . (Qin et al2020)
· Understanding
o Maxillary sinus remodels itselfwith tooth movement
o Increase in resistance to toothmovement, greater tipping.
Periodontal boundaries
Carlos Flores Mir started the topic with a thought provingquestion, that we are well aware of Proffit’s envelope of lower incisor dentalmovements; but the question of whatis the periodontal limit, is still yet to be clearly defined.
The difference between the gingival biotype and phylotype,there has been a focus on biotype but it
· Biotype – thickness of gingiva inbucco-lingual direction
· Phenotype – contour gingiva,underlying bony architecture, and width of keratinised tissue
Thin gingival biotypes are likely to have more chancesof recession.
Factors to consider
· Extraction Vs non-extraction: inboth scenario the bone height decreases, but in different locations, anteriorextraction treatment = 2mm reduction, non-extraction = 1.2mm. www.orthoinsummary.com/blog
· Dehiscence exist pre treatment
· Thicker the gingiva, the better Yared2006
· Initial position of the toothdecides its periodontal future
· Thickness varies in various areasof the mouth.
· Oral hygiene major factor ofrecession Melsen 2005.
CBCT
· Aren’t really telling us the wholestory –
· Size of the image of a CBCT islimited by the radiation dose, and typically is 0.3-0.6mm3 of voxel size
· Tissue less than 0.6mm appears as aabsent in CBCT giving false positive results ( Redua 2020)
Lower incisor proclination and recession:
· Systematic review Kalina no correlationbetween proclination and gingival recession. (Kalina 2022)
Understanding
Recession = Thin gingiva + proclination +periodontitis
Contents– Shanya Kapoor
Editing and Production – Farooq Ahmed
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Orthodontics In Interview: RICHARD COUSLEYDigital orthodontics, miniscrews and aligners“Aligner set ups need to be orthodontically checked to make sure it is realistic, and an accurate representation of what you are trying to achieve”Richard describes his journey into digital orthodontics, what led him to create his own successful miniscrew system, and why he has continued to innovate in orthodontic with 3D printing.Richard describes what he thinks stifles innovation in orthodontics, as well as how CBCTs have improved his miniscrew success rates. Please like and subscribe if you find it useful!To book Dr Richard Cousley’s 3D orthodontic course, please see: https://www.3dorthodonticscourse.com(no financial interest)#orthodontics #farooqahmed #richardcousley #aligners #digitalorthodontics #infinitas #miniscrews #orthodonticsinsummary#orthodonticsininterview Farooq Ahmed
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Join me for a summary of two lectures from this year’s international orthodontic symposium (IOF), looking at mouth breathing and paediatric obstructive sleep apnoea, by Hong He and Carlos Flores Mir. The lectures explore this controversial area in both medicine and orthodontics and review the current understanding of the topic, the relationship with facial features and current recommendations for orthodontists.
OSA is defined disruption to breathing American Academy of Sleep Medicine
Adult > 5 apnoea/hour & 10 seconds
Child apnoea for duration of 2 breaths 1
Defining mouth breathing at airflow over 25% through the mouth
Evidence of craniofacial effects
Mouth breathing
Retrusive maxilla -1.33o (SNA -2.03 -0.63)
Retrusive mandible -1.4 (SNB -2.20—0.6) Zhang 2020 SR
Increased mandibular angle 3.38o (2.77-3.98)
But is mouth breathing pathological?
pOSA
no craniofacial difference in pOSA vs controls SR Fagundes 2022
Recent study by Carlos Flores Mir, combine factors
Demographics, lifestyle, craniofacial features and sleep features. Investigating effects of treatment on these categories
Treatment
Twinblock improves pOSA AHI 14.08 to 4.25 in the short term, severe to mild Zhang 2012
MARPE increases cross sectional area, by 40% oropharynx, 7% nasopharynx Zhao 2020
RME increases nasal airway volume initially of 1604 mm3, but reduce to 579mm3 after 3-5 months and non-significant SR Zhao 2021
Tonsillectomy
Does not stop mouth breathing, even if OSA resolved Bae 2020
Conclusions
Breathing involves complexity of 3D structures and fluid dynamics is not well understood
Mouth breathing does seem to have craniofacial influence, however OSA does not
Orthodontists role in OSA
screening for OSA
Refer to physician if risk factors present
Refer adenoid hypertrophy to ENT
Contributions
Contents and video editing – Shanya Kapoor
Editing and Production – Farooq Ahmed
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