March 04, 2016

A “thinking about orthodontics” blog post

A “thinking about orthodontics” blog post

This is a short blog post to read just before the weekend, or just after if you are in Australia!  I have just attended a major symposium in the UK and I was asked to give a major lecture.  The preparation of this took some thought. During the meeting I listened to some great presentations and this got me thinking about orthodontics.  I have been working as an academic orthodontist and research since 1986, spent a large amount of time researching clinical matters, I have trained too many people for me to remember and spoken at many major orthodontic conferences.  But what do I know about orthodontics?  Here is a list of my academic knowledge and opinion.

This is a precursor to a more thoughtful blog post that I am going to post next week, so here we go. You may not agree with me..

  • Malocclusion is caused by a combination of genetic and environmental factors
  • There are many ways to treat particular malocclusions.
  • Evidence based orthodontics is a combination of clinical experience, patient opinion and scientific research.  The proportions of influence of these factors varies according to our level of scientific evidence.
  • Arch form and dimensions should generally be accepted
  • Functional appliances and other bits of plastic, pistons and springs do not change or influence facial growth. They tip teeth.
  • To my knowledge there is no high quality scientific proof that orthodontics, extractions, appliances, expansion, myofunctional orthodontics influence breathing, posture, academic attainment, sleep disordered breathing etc
  • Class I molar non extraction treatment is very easy
  • I wish that I knew how to intercept malocclusion…
  • Extraction of permanent teeth is required for the treatment of some malocclusion..but treatment mechanics are as important as the extraction decision
  • You can only “drive” upper molars 2 mm distally
  • Temporary Anchorage devices are better than other anchorage reinforcement method by about 2mm
  • Wire and bracket properties do not influence the efficiency of alignment
  • None of the new developments that are supposed to speed up orthodontic treatment seem to work; according to new trials..
  • There is no such thing as non-compliance treatment
  • I simply do not understand clear aligner systems
  • Self Ligating brackets do not have any advantages over conventional brackets.  The self ligating practitioner should explain this to their patients.
  • The alternative orthodontist should explain to their patients that there treatment is not mainstream.
  • The General Dental Practitioner who has been on a short  course to learn speedy orthodontics should explain to their patients the limitations of their training and knowledge
  • There has been and there continues to be great high quality research being done in orthodontics and don’t tell me that our evidence base is weak!
  • Nearly all orthodontic treatment relapses to a degree and this is probably caused by ageing and we cannot stop time…………….

That’s about it, does anyone want to add to the list?

Related Posts

Have your say!

  1. I would like to add a statement about RPE.

  2. my thought is that in orthodontics (for all practitioners) is that we don’t know, what we don’t know… and in orthodontics there is a lot of what ‘we don’t know’, but little admission to our colleagues and patients that we don’t know….

    • Totally agree with Ross….. When I reflect on what I was taught and what I see …… I may be drifting to the dark side but I keep an open mind (not too much so my brain falls out) but sometimes reflection is a powerful tool….and asking ‘but why’ (which got me labelled as troublesome in Bristol) but if we don’t poke the box….

  3. Thank could you add tmj discussion and evidence base
    I thoroughly enjoy and appreciate your efforts on this blog and the introduction to dental elf

  4. Dear Kevin,
    Some points I would like to see in your list:
    Temporomandibular joint and Orthodontics;
    Quality of life and Orthodontics.
    Best wishes,
    Klaus

  5. Well said Professor!

  6. I would also paraphrase Dr Lysle Johnston that “nobody ever died from malocclusion”! ?

    • disagree . The united states medical officer when he viewed Alred Fonders work about dental distress syndrome , stated it would take 15 years of a persons life expectancy with its ragbag of symptoms including high blood pressure , dystonias , postural problems , psychological symptoms etc . Having have extraction based treatment induce migraines , and had to correct it myself , by reversing the mechanics , I completely agree with this dramatic statement . Watch dentist Brendon Stack treat/ cure tourettes patients on you tube . Its not just about teeth . Part 2 – Dr Brendan Stack’s Treatment for Complex Temporomandibular (TMJ/TMD) Disorder

  7. I would add statements about orthodontics and the perception of it by laypersons:

    Patients do not perceive need for treatment as we professionals do.

    The range of acceptability for anterior aesthetic dentoalveolar variables by most laypersons is wider than ours.

    The real impact as well as the timing in quality of life, day-to-day activities and oral function of orthodontic treatment for laypersons is still not clear.

  8. Dear Kevin,
    It was a pleasure to meet you and hear you speak at this symposium.
    Another one for your list …. cephalometric analysis in orthodontics.
    Best wishes,
    Raman Aulakh

  9. Patient diet and oral hygiene can sometimes make end result worse than start point – assess carefully before commencing treatment

  10. 1: Almost all treatment is carried out to improve appearance
    2: The alignment of the lower incisors in itself is of no benefit to the patient and it is possible to leave them irregular in quite a few cases. Remember they move as you age anyway, maybe you should let them.

  11. We should learn from our relapsed cases what are the steps we could have done differently
    Stick to what works for you

  12. To which I would add:

    Way too often wisdom teeth are wantonly “amputed”

    Canines are not sacred; they can be “removed” when the indications warrant it

    Sometimes its better to leave an impacted tooth impacted

    Premolar extractions can lead to lingually inclined upper anteriors and coupled with a deep vertical overbite and shallow articular eminence can predispose to TMJD

    IPR can spare many an unnecessary “extraction”

    Dental professionals should provide weight control services in their offices: http://www.drted.com/ojw-forms/

    • agreed , good point . Upper arch extractions reduce the vertical , compress the joint, and symptoms occur later in life . Not always , but a good many times . The effects are life ruining . Class three lower arch extractions don’t cause this generally . It is class 2 camouflage treatment (upper arch extractions) that generally cause the problems .

  13. I have found your blog recently, I find it very refreshing. Despite to not agree at 100%, the reflection about all biomechanics must keep us thinking about straight wire appliance, its limitations, and furthermore the problems inherent to these mechanics. For example, given torque with a single rectangular wire is inefficient and increased friction significantly with all problems derived. However, it still the cornerstone to current biomechanics. More over, the only way that self ligating brackets could be effectively used remains i not to be used as a strength wire appliance.

    Love your blog, keep doing great reflections!!

    Regards

  14. Thank you for your excellent post which is a validation of my own thoughts regarding the drawbacks of orthodontics, particularly the issues of efficacy of clear aligners, self-ligating systems, angles cut in the slots that differ a bit in different systems and the treatment relapse.
    In addition to the astute points you’ve made, I’d like to add the following observations:

    *Nature and Time are two big helpers of most of the orthodontists to survive in same way they help endodontists with incompletely filled canals, prosthodontists with imperfectly prepared margins and conservative dentists with overhanging proximal restorations and many general practitioners with the left out apical root pieces of mainly roots with curved apical third.That is not to say that that ideal orthodontic treatment for a particular condition with excellent treatment result does not exist that is very few and far between.
    * Not only self ligating practitioners but *every* practitioner of orthodontics has the moral responsibility to explain to the patients the drawbacks of orthodontic treatment in general..but then that’s what the informed consent is all about..but unfortunately only a small percentage of patients/parents actually go about reading it in detail.

  15. “You can only “drive” upper molars 2 mm distally” Why exactly 2? What about distalization after extraction of 3rd molars?

  16. There are some techniques that seem to help reduce treatment time and risks of decalcification. Hopefully the devices that do not work as claimed are removed from the market as soon as possible to reduce the costs to practitioners and patients.

  17. Slow maxillary development.

  18. Hi Kevin,
    a good list, I liked each and every point. However, for me, the unspoken dominant truth of orthodontics pertains to aesthetics. Your list reflects your interests and strengths and I suspect my list does the same for me. I wondered whether stating malocculsion is normal or an ideal occlusion is abnormal was appropriate but I chose not to include that.

    My list to augment yours is:

    Most orthodontics is optional

    Most orthodontics is for (usually dental) aesthetic concerns and the aesthetics may be considered on two levels.
    The first would be the Moorees and Keane level where orthodontics addresses (corrects) a patient’s dental deformity
    The second is enhanced aesthetics, it is the orthodontists need to clarify in detail and ensure all parties are aware of the goals and changes

    AEsthetics has so far eluded efforts to define it with ratios and other mensuration and when listening in lectures to someone who ‘tells me’ this is a measure of dental beauty, I know that so far, none has been validated so i am probably being mislead. For example: do a search to see how poorly ‘divine or golden proportion’ performs when tested in dentistry, Mario Livio (read his book on phi) found the same lack of ‘success’ with it in art and other fields.

    Teeth are solid objects often typically shaped. Orthodontists arrange them. The better the knowledge of the geometry of the teeth, arches, supporting structures and overlying soft-tissue form with it’s variable muscular function the greater the chance of creating a more pleasing orthodontic result.

    Diagnosis and treatment planning prior to treatment is important but at least as important is responding to the individual and their response during treatment, response and co-operation cannot be known prior to treatment hence our incapacity to be certain. For example: the point immediately previous is often not fully knowable until well along the journey of treatment. And then the points on aesthetics are not fixed in time in a patient’s mind and they may change of time, including over the course of treatment. Therefore: Predetermined treatment that is not refined during treatment is often suboptimal.

  19. Kevin.
    I would love you to expand on your statement “Malocclusion is caused by a combination of genetic and environmental factors”. Are you saying that there is a gene for narrow jaws and crooked teeth? If so, when did this gene undergo its mutation – because anthropological studies from as little as 400 years ago, across a number of different races, show no malocclusion – and a well developed arch with room for all 32 teeth.
    Your next statement is that environmental factors cause malocclusion. Could you explain what these environmental factors are and how they cause the jaws to narrow.
    Orthodontics seems to be much more of an art than a science – because science dictates that comparisons be made on subjects that are as identical as possible before conclusions can be drawn. No two human beings are the same – everyone has slightly different issues – functional as well as underlying – and I am sure that over the years you and many of your colleagues have been perplexed that what you thought was going to work – simply did not. There was nothing wrong with what you did – there was something different in the underlying factors associated with the cases being compared.
    To try and achieve the evidence based scientific research you refer to – “To my knowledge there is no high quality scientific proof that orthodontics, extractions, appliances, expansion, myofunctional orthodontics influence breathing, posture, academic attainment, sleep disordered breathing etc” is virtually impossible. You will be trying to prove a negative – and besides which – it is ethically unacceptable to extract teeth to try to prove a point.
    Sometimes the evidence is in the observation – much like the fact that manufacturers of Thalidomide saw a spate of deformed babies and withdrew their product. They did NOT run a second double-blinded trial to PROVE that their drug caused deformities. Research is valuable but not infallible, and not always appropriate when stacked up against observation and common sense. Very difficult to research an Art. In my 50 years plus in practice – dealing largely with breathing disorders – the numbers show clearly that there is a direct correlation between poor posture, poor tongue position, open mouth breathing, extraction orthodontics, NO orthodontics – and Sleep, Asthma, Apnoea, Concentration and Energy levels, and general lack of good health. This is also so obvious in races which have adopted the Western diet and are suffering the consequences.
    To paraphrase the International Marketing Director of Pfizer when asked to comment on a $50 billion investment in China. “As the Chinese become more Westernized they are developing the diseases of modern living – and we make drugs to address those problems”. Not publishable research – but it tells a story.

    • Hi, just an extension of what you have said, and a summary of the orthodontic problem, is that we don’t realise that no two patients are alike. We tend to get into dogmas and schools of thought very passionately, and tend to inadvertently apply the same principles to all patients, disregarding individual biology. This is where the experience of the orthodontist comes in, where the appliance should be chosen as per the needs of the patient, and that thought process is what breaks the monotony in orthodontic treatment tof different individuals, and can also help in increasing the percentage of successfully treated cases.

  20. To add to your list:
    Brained F. Swain, DDS taught me that the difference between a good Orthodontist and a great Orthodontist is Attention to Detail.
    Enjoy your blog posts. Often share them with my grad students.

  21. Add to list:
    TADs can fail. The patient in which the plan is totally reliant on the success of TADs must be informed of the risks; otherwise tears for both the patient and practitioner.
    Non-extraction plans with TADs just because it can be done are not necessarily better, faster nor more simple than extraction based plans.
    Speedy orthodontics by non-specialists such as the various six month treatment philosophies do not use magic braces and wires. They are the same as so called conventional appliance systems. Most of the time it is overpriced and underwhelming in terms of the results.
    Specialists sometimes do so called six month orthodontics. The difference is they are fussier in terms of case selection.
    Evidence based practice. We should all be fully supportive. The fact that improper orthodontic treatment doesn’t kill people saves us from more serious repercussions from poor and ineffective treatments. Imagine drug treatments in a world without randomised clinical trials.

  22. Dear Prof O’Brien,
    I would like to thank you for sharing your experience and knowledge through this blog.
    I assume that by stating that Functional appliances and other bits of plastic, pistons and springs do not change or influence facial growth- they tip teeth, you refer to the treatment of Class II cases. Can I add to your list treatment of Class III cases with reverse Headgear and Chincup, and how these appliances can influence facial growth?

  23. Thanks Kevin, I’m in Aus and it is still the weekend!
    Enjoying the list, agree with other bloggers – would love to hear your summary on TMJ and cephalometric analysis.
    My curiosity peaks when I read the 2mm distalization limit and lack of comprehension of clear aligner systems. Would love to determine the reason/s. In relation to the latter – is it a lack of belief that plastics may produce moments and forces capable of moving teeth, a discomfort with systems that do not express “fully”, or as programmed (as with brackets and wires, we just cant see it as easily as we have no end-point unless digital and we have learned how to compensate mechanically); perhaps a lack of gold standard scientific research (as with fixed appliances; they have a century head-start), or a distaste for the pop-culture that manufacturers of these systems tend to encourage, other? Personally I do relate to all of these attributes of clear aligner systems but in my 19 year experience of testing and teaching such systems I conclude that it mainly comes down to wanting to work with them, therefore needing to understand them for all their strengths and weaknesses. If you have an appliance system that works great in your hands, earns you a steady income and resolves most orthodontic predicaments, there is really little reason to understand them. That’s simply my observation. I would like to know why YOU say it, ’cause I think that you try to understand everything in our wonderful world of ortho! Have a great weekend! VV

  24. Hi Kevin,
    Thanks for a great list. Some great points made in the discussion too. I would also add that (in most cases) patients should be made aware that retention is a life-long commitment. Your list reminded me that what patients want and what we as orthodontists want are not always the same thing – maybe that is why six month smile/clear aligners/fastbraces etc are so popular. The title of your blog also reminded me of a dental colleague who described orthodontists as “the hairdressers of the dental world” (with apologies to any hairdressers reading)…

  25. Hey Kev , love the blog , but allow me to disagree with you on few points !!
    This is what I know.
    * Functionals do work, just not as well as we would always like to completely reduce an over jet. Yes they tip teeth and distalise the upper arch . Not great .
    * Often with disclusion the mandible will track forward of its own accord with out a functional . Predicting this is difficult .
    * To extract upper premolars to correct an over jet , can entrap or distalise the mandible , reduce the vertical , and compressing the tmj .This resuls in poor posture and
    migraines .
    * It is ok to extract upper premolars if the patient is truly prognathic ( Sassoni arc , or Jefferson analysis ) and the mechanics do not over retract the incisors and compress
    the joint . True maxillary prognathism is unusual in modern caucasions . Most have undeveloped lower faces .
    * Alveolar bone grows with light forces . ALOT , both horizontally and vertically .
    * Its not ok to extract simply for crowding , with out reference to lower face volume ,or with internal derangement of joint. i.e. a click .(40% of population click )
    * Patients with extracted upper premolars , age terribly , as the upper lip further collapses .
    * Of coarse PSL are no quicker if used on an extraction basis . All the quoted studies I read were extraction based . This is poor evidence to
    dismiss PSL at what they are good at .
    * PSL brackets are better than twin brackets at unravelling very crowded arches and giving beautiful full faces and smiles . Lighter forces make bone grow . Its as stable as
    extraction treatment . Ie not very !
    * Relapse of a non extraction case does not medically compromise the patient later in life .
    * Relapse of an extraction case often will further medically compromise the patient later in life .
    * I have stuffed up plenty of cases also . we all have , and will continue to do so until some common protocols are formed unifying orthodontic treatment .
    * I’ve had a hell of a time retreating myself to decompress my own Tmj , following extract and retract upper arch treatment . ( I was a mild class 2 div2 )
    I have done it three times and three times headaches have gone . As soon as it relapses the migraines have returned . This time Ive committed to full therapy and increasing
    the vertical and functioning the mandible forward and has made me feel 15 years younger. All pain gone , ( I was getting 3 migraines a week and losing a day in bed a month ) Voice improved in strength . I look facially better . Posture improved .
    * If i wasn’t a dentist I would have no clue !
    * Teeth and bite 100% affect posture .
    * Non extraction treatment looks a hundred times better facially than extraction based camouflage treatment . Camouflage cases can rarely go on to model . They are just
    too ugly !
    * If a patients over jet will not reduce with a functional I still think they look better with a full arch of upper teeth , and accept the over jet , when considering the alternatives.
    * To focus fully on Andrews six keys of occlusion ( over jet ) and forget facial volume and tmj health is a mistake.
    * GDP treatment instinctively tends to avoid extraction based treatment ( trying to do no harm ) and they inadvertently achieve this . I see qualified orthodontists being more
    confidant because they are trained , over extract and cause the most horrendous health problems for our patients , by completely ignoring TMJ compression .

    * Please watch orthodontist Brendon Stack on you tube and tell me what the hell he is doing to cure , migraines , tourettes , parkinsons , bowel conditions etc etc etc .Please
    watch if you are a dentist it will change you opinion of what we should be doing as a profession .
    * Kev I would love your opinion of what Brendon is doing !
    * Sorry for the lecture folks but I do think we all have something to add , and with out discussion we go no further . Kev is to be praised for raising the debate .
    Replys welcome .

    • Peter I agree with you as I see all the above in practice, and sometimes worse. People sometimes crippled with pain post extraction treatment.
      I suspect the orthodontists don’t understand /believe these problems exist because they don’t see the problems.
      They often occur many years after treatment, and in my experience, if they revisit the orthodontist (difficult for NHS patients over 18 years) are told it is nothing too do with the orthodontics.
      Kevin, I would love you to see some of the cases that I see in general practice, try and treat one and be successful with it and you will be swamped- there are so many out there. Look at the TMJ forums for some of the opinions the patients have!

  26. Hey Kevin, just a note of congratulations on your choice of words in your latest rumination on orthodontics, vis a vis,
    “driving maxillary molars distally 2mm.” You avoided the commonly and erroneously used term “distalize.” We don’t
    mesialize, intrudilize or extrudilize, so why do editors continue to allow contributors to use this linguistic abomination.
    You can retract maxillary molars or distally drive maxillary molars, you just should not distalize them. Hope your neck
    is better by now.

    Larry White

  27. 1 – Orthodontics can be learned by general dentists; but not in a 2 days course. It has to be taken seriously, like everything else we do!
    2 – General dentists can perform excellent orthodontic treatments to their patients when applying rule number one
    3 – Dr Angle is the father of modern orthodontics
    6 – The orthodontic world still admire the work of Dr Angle
    4 – Dr Angle learned orthodontics by himself
    5 – Dr Angle was a general dentist who self proclaimed himself an orthodontist
    6 – Dr Gerry Samson said: “There is not only one good way to do things, otherwise we would all be doing it”
    7 – Lysle Johnston said: “Orthodontic is not a business of perfection, but a business of improvement”
    8 – You dont need to be a specialist to be an expert
    9 – People do not care about the difference between general dentist and orthodontist: what they want is to have confidence in their treating doctor… and to be seen on time at their appointment 😉
    10 – Spending money to explain to the public what is the difference between an Orthodontist and a General dentist is a waste of money and a waste of time. People dont care!
    11 – The AAO should spend money on explaining the importance of orthodontic examination at a young age and educate people about it.
    12 – If orthodontist and general dentist would live in harmony and if orthodontist would be open to teach how to diagnose and treat easy cases to general dentists, orthodontist would do more orthodontic treatments and would have more referrals.
    13 – It is fun to imagine some of your faces while reading these 12 previous points!

  28. Discovered this blog recently
    Thank you for sharing your thoughts : The topics are relevant and often subject of ongoing debates. I recommend reading the comments which are often Very interesting
    1-I Disagree partially about self ligation : it is obvious PSL make the initial phases of alignment easier ( but the finishing phases might be a little more difficult )
    2-Clear Aligners sponsored meetings and claims of the companies will I’m afraid kill orthodontics
    All opinion leaders must react NOW and explain what IS the real place of Aligners in the orthodontic treatment

  29. https://www.youtube.com/watch?v=JGlDCyZGkoc
    Hi Kevin , (Thinking about orthodontics)
    Brendon Stack is an 80 year old orthodontist successfully treating tourettes , movement disorders , dystonias , bowel conditions , all spin off from his headaches and migraine treatment , by opening the vertical and repositioning the condyle in the fossa , down and forwards . He then erupts the posterior teeth to the new vertical . My particular favourite is the girl he helps walk normally again from being wheelchair bound . Look at “track and field star Brendon Stack” , on you tube .
    He has been doing it most of his career . He has over fifty or so medical miracles posted on you tube that need to be looked at to be believed .
    I think these techniques should be taught at dental school ?
    Your opinion would be greatly appreciated .
    If you are a dentist / orthodontist please watch , and pass opinion . Love to know what you think about it .

  30. Orthodontics = think global, act local

  31. Since you are discussing evidence-based care, there were a couple of statements made about PSL brackets being superior (particularly in non-extraction cases) and I have to disagree as the evidence is fairly clear that there is no difference. I agree a lot of the evidence from RCTs is in extraction cases but in the Angle Orthod 2006;76:480–485 during initial alignment (non-extraction) there was a very minor (not clinically meaningful) difference in favour of conventional brackets during initial alignment. In Am J Orthod Dentofacial Orthop 2010;137:12.e1-12.e6 there was no difference in non-extraction cases between PSL or ASL brackets. In light of this it cannot be supported by the current evidence that PSL brackets are superior during initial alignment so it then comes to a personal preference as to which bracket you prefer to use as a clinician.

  32. This is a great view of some fundamental orthodontic thoughts. Every Ortho resident should read this to prompt some good discussion!

  33. Thanks for the blog Kevin, it’s a great contribution.

    What’s not to understand about clear aligners? Like most force delivery systems they have advantages and disadvantages, and good and bad suppliers, and good and bad operators. Lots and lots of happy patients worldwide, probably lots of unhappy ones too.

    Probably the reason why we don’t have so much evidence about them is because in the UK they are usually provided outwith the NHS, which is the treatment offered by most institutions who do the research. The people who do the bulk of our academic teaching also reside in the same environments, so ortho postgrads don’t get much of a grounding in the appliance. As Wilde said “experience is the name we give to our mistakes”. We should be able to avoid problems and mistakes with aligners if there was more academic “understanding”.

  34. Growth and cooperation = ” success “

  35. Evidence based care is about clinical experience and research which form a triumvirate with patient opinion says

  36. Generally speaking, how much of an orthodontist’s patients come from referrals and how much from direct marketing? I guess it depends on practice to practice, but is there a typical amount? Are there orthos who get by without any referras?

  37. My opinion about orthodontics is that they give long life for our teeth by doing proper treatment. You can get more beautiful and healthier smile.

  38. Kevin,
    I’ve been practicing for 27 years. Is there any evidence that orthodontic treatment improves one’s oral health over the course of a lifetime? I realize that treatment can greatly influence self esteem. But this is primarily esthetic in nature. Is malocclusion a physical disease? How many patients come to us to fix their “bite”? And even if they, do isn’t it mainly because their “bite” isn’t esthetically pleasing. People can live perfectly happy lives with a malocclusion. And in my experience, have just as good oral health as anyone with perfectly straight teeth and a Class 1 occlusion. Sometimes I think we are disingenuous when patients ask us what will happen if they don’t receive the treatment we recommend. What negative consequences will they experience over the course of a lifetime? After years of experience, I must say “Not much”. My main point is that we are not doctors treating a “disease”. If we were, no one would even talk about marketing a practice. Physicians don’t market their practices because they don’t need to. They are treating physical disease; patients actually feel physical relief with treatment. So, here is what I have learned.

    1. Orthodontic treatment is a choice.
    2. Malocclusion is not a disease state.
    3. Patients seek us out mainly for esthetic purposes.
    4. Orthodontics can have an overwhelmingly positive influence on self esteem and contribute greatly to one’s quality of life.
    5. Orthodontists take themselves too seriously.
    6. We would not have a job if we lived 150 years ago.
    7. We are obsessed with a Class 1 occlusion.
    8. We should not be obsessed with a Class 1 occlusion.
    9. Orthodontics is fun.
    10. I am personally grateful to be in a profession that can positively affect people’s lives.

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