It depends on the age, the inferior alveolar nerve block is a good opsion, currently is managing the extraction of wisdom teeth in children, when they are very damaged by hypomineralization long as you have the second and third permanent molar healthy, and promote mesial eruption.

Yes, it is difficult to get hypomineralized first molars anesthetized, because of pulpal nature of those teeth. Intrapulpal injections (with conscious sedation) after caries excavation will do, but it is little difficult with a child who is already experiencing severe pain.

thank you Dr Shubha,

Dr. Pammi,

I have the same difficulty. I have always remarked how difficult it is to get these teeth adequately anesthetized. These teeth are often found in 6 year old children soon after eruption. These young permanent teeth are exquisitely innervated in contrast to the primary dentition that is bioenginered to be destroyed on eruption of the succedaneous tooth. Also, these children have not yet developed mature down modulators to pain (e.g. voluntary control of attention, pain inhibitory controls) so that they are already primed for robust pain expression. Children under 7, in general show five times more distress for the same medical procedure than children 7 and above and not everyone conforms to that developmental schedule.

So what I do is to carefully excavate all of the active, soft caries and place a glass ionomer restoration for 6 months to two years. The fluoride release desensitizes the dentin, inhibits secondary caries and I have no problem getting these teeth numb thereafter. Since the soft, active caries are necrotic debris that is not innervated, I usually do not use a needle procedure to anesthetize the tooth in order to excavate caries. These restorations need vigilance and maintenance. The family needs to be committed to establishing a dental home for their child. I tell my parents this and make them understand that I need to see the child regularly and that I may have to repair the restoration or resort to sedation if this strategy is not working for their child.

By the way, I am very much consoled to hear that you have the same problem I have all the way over in your neck of the woods.

thank you Dr Nutter.

I fully agree with Dr Nutter's first paragraph stating how and why hypomineralized first permanent molars are difficult to anesthetize. I agree with Dr Pammi's statement that both upper and lower first molars are equally difficult to numb.

On the other hand, I cannot follow Dr Shubha in his opinion that "Intrapulpal injections (with conscious sedation) after caries excavation will do". As far as I know, concious sedation is definitely not an analgesia. Moreover, treating these hypomineralized molars does not imply systematically performing a root canal treatment. And I strongly believe that intra pulpal anesthesia is the surest way to keep a child -an adult as well- out of any dental chair for the rest of his life. We should absolutely get rid of intra pulpal anesthesia : this is just an opinion.

Now, bak to the problem :the reason why hypomineralized first permanent molars are difficult to anesthetize is that hypomineralization induces a chronic permanent stress to the pulpal tissues,i.e, a chronic pulpitis. And I believe that teeth with chronic pulpitis are more difficult to anesthetize than teeth with acute pulpitis - even this can seem rather astonishing!

The best method to anesthetize these teeth is intraosseous anesthesia, either as a complement to other techniques, or as a primary (first-line) technique. I use these techniques as first line anesthesias. The intraosseous anesthesia consists in injecting the anesthetic solution directly in the spongy bone surrounding the dental roots.

I use the French system called "Quicksleeper" ( invented by a French dental surgeon, Dr Alain Villette, and produced and marketed by a French company Dental Hitec). It allows the penetration of the needle into the spongy bone by passing the cortical plate by a rotation of the needle. The other advantages iare a computer controlled injection, and a pen-grip allowing a most precise manipulation of the needle, contrarily to any other seringes or systems (with the notable exception of the Wand). These intraosseous anesthesias (transcortical, osteocentral) can be used on children from the age of 6 months until 6-7 years without rotation of the needle, and on children aged 8 years onward, with rotation of the needle, as the cortical plate is harder. On permanent first molars, the osteocentral technique is preferred : it uses a 16mm needle penetrating the distal interdental space. The anesthetic formulation is lidocain 2% with 1/100 000 epinephrine or articain 4% with 1/100 000 epinephrine.

The volume injected is much lower than with IAN blocks,there is virtually no risk of soft tissue anesthesia (lip or tongue biting), and the analgesia provided is optimum. The analgesia is of of relatively short duration, which is a great advantage on children with which, in my opinion, dental care should not exceed 30 minutes.

Thank you Dr. Collier. This is very informative.

I am somewhat disappointed that my intervention on the topic seems to have put a final point to the discussion : is it that my argumentation was so convincing that everybody has decided to make intra osseous anaesthesia their primary technique...or what else?

Hi there.

The remarks of Dr. Collier regarding the intraosseous anasthesia are very interesting. We use a combination of terminal anaesthesia and intraligamentary anasthesia with the Wand for MIH-molars quite succesful. Besides lidocain or articain + adrenalin 1:200 000 we use mepivacain. Mepivacain provides a deeper anaesthesia but for shorter time.

Hi Theirry, I haven't looked in here in a while but I certainly want to compliment you on your excellent suggestion for "good clinical pediatric pain practice". It certainly will motivate me to try out intraosseous anesthesia for the my pediatric patients. I do agree with your statement that dental care for children should not exceed 30 minutes.

Currently, while I try to stay away from needle procedures (in the mandible) in children under 7, for those hypomineralized molars in 6-year-olds it is just not possible if they are going to display pain behavior during invasive treatment. Therefore the prospect of placing anesthesia into the marrow space between the two buccal roots on the maxillary first molar or the mesial and distal root of the lower first molar interests me. Question: is the target space for placement of the anesthetic between the roots of the same tooth or between the roots of adjacent teeth?

I have begun to use Gow gates technique for mandibular molars and Posterior superior alveolar nerve block for maxillary molars. It has definitely improved success rate of achieving anesthesia on hypomineralised molars

In addition to all these good advices, the use of rubberdam in treating MIH-molars is also needed. Other not anesthesised MIH molars are protected by the rubberdam from the cold water.

Marlies - I always thought that it was the hypomineralized molar would be more cold sensitive than the other teeth. Has it been your experience that placing a rubber dam reduces cold sensitivity?

Re Dennis - The hypomineralised molars are the most sensitive. But most of time, it is not only 1 molar that is affected by MIH. So when you treat one molar, please use rubberdam to prevent cold water on the other MIH-molars.

I hope it is more clear this way.

Okay. Now I get it. Thanks for that clarification. You are not talking about teeth in the same quadrant but other Hypomineralized molars in the opposing quadrant. I don't usually have to worry about water spray because I am not touching these teeth with a high speed hand-piece initially. My first action is to use a slow rotating round bur to remove active decay (and anything else that I can get atraumatically) and place glass ionomer as a transitional restoration. ( I use Fugi IX)

(Next paragraph is an expansion of my previous answer) So what I do is to carefully excavate all of the active, soft caries and place a glass ionomer restoration for 6 months to two years. The glass ionomer's fluoride release desensitizes the dentin and inhibits secondary caries. I have no problem getting these teeth numb thereafter to so a more definitive restoration.

Since the soft, active caries are necrotic debris that is not innervated, I usually do not use a needle procedure to anesthetize the tooth in order to excavate the caries during the first restorative procedure. Of course the children must not be showing pain behavior while I am cautiously excavating the caries either. Otherwise, they will need plan B. (Which is slang for "alternate plan" here in America. Sorry if this is a fundamentally understood concept in Amsterdam.) I do have these kids on nitrous oxide and they have previously demonstrated during a trial exposure (Show-tell-simulate) that they have been desensitized to the mechanics of the procedure and can tolerate the procedure's non-nociceptive (pain) stimuli. This type of procedure is elected as a type of pain intervention that avoids more invasive or risky alternatives. Most parents are very appreciative of this type of treatment pathway. Especially as most of these kids present with the problem before they have had significant maturation of their pain inhibitory controls. (Kids under seven, in general, show five times more distress for the same medical procedure than children 7 and above [Jay SM, Ozolins M, et al, Assessment of children’s distress during painful medical procedures. Health Psychol 2:133-47, 1983.] )

These restorations need vigilance and maintenance. The family needs to be committed to establishing a dental home for their child. I need to see the child regularly and if need be I am not averse to increasing their frequency of observation.

First of all, I would like to apologize for my late reply to the question by Dennis Nutter. I have been away from home for 4 weeks (Indonesia and Malaysia…on MAS aircrafts!), with little or no connection to the web.

Now, I give you more details on intraosseous anesthesia for children, as the initial problem was : "Enamel Hypomineralization in molars : I have highest failure rate of securing local anesthesia [ both mandibular & maxillary ) first molars", wasn't it?

We describe, in Europe, 2 types of intraosseous (intra diploic, inside the diploe) anesthesia :

-transcortical : consists in injecting the anesthetic directly into the cancelous bone after crossing the cortical plate with a drill or with a rotating and perforating needle (8mm long, and 0.3 or 0.4 mm diameter) (Quicksleeper system), at right angle to the cortical plate surface.

-osteocentral : the perforation point is similar to an intraseptal anesthesia, but you insert the needle vertically much further into the interdental space, with a loger needle ( 12 or 16 mm long, and 0.3 or 0.4 mm diameter.

On permanent teeth,

-between the ages 6-9 : for anterior teeth and first molar : transcortical anesthesia without rotational system for peforing the cortical bone. Generally, at that ages, bone is rather easy to perforate by a simple pression on the needle (8 mm, diameter 0.3 or 0.4 mm)

-between the ages 10-16 :

+for anterior teeth : transcortical anesthesia with rotation

+for first maxillary molar : transcortical or osteocentral anesthesia with rotation

+for second maxillary molar : osteocentral anesthesia with rotation

+for first mandibular molar : transcortical or osteocentral anesthesia with rotation

+for second mandibular molar : osteocentral anesthesia with rotation

You will use less than 0.9 mL of an anesthetic formulation with epinephrine. I consider hypo mineralized teeth as chronically inflamed teeth, and this implies to use an anesthetic formulation with 1:100 000 or, better, 1:80 000 epinephrine. The onset will be immediate (as soon as the injection is over, you can begin to treat ); there will be no or minimal soft tissue anesthesia. If you want to install a clamp for thre rubber dam, no supplemental anesthesia is required.

Moreover, in the maxilla, you can anesthetize 2 teeth distally and 3 or 4 teeth mesially to your injection point, depending on the amount injected. You can make the anesthesia either on the labial or the palatal aspect of the tooth.

In the mandible, you will anesthetize one tooth distally and 2, 3, or 4 teeth mesially, because the vasularisation of the mandible is unidirectional, postero-anteriorly oriented. So, when anesthetizing a mandibular molar, always try to inject in the distal interdental space (transcortical anesthesia) or in the inter radicular space of the molar tooth (osteocentral anesthesia). The injection is made on the buccal aspect of the tooth.

I understand Dennis point of view, but I prefer anesthetizing systematically, because, as demonstrated by Sixou and al. these intraosseous anesthesias are very well tolerated by children (no "big shot").

I also would like to point out that, for numbing the attached gingiva prior to performing the intraosseous injection, I never use any kind of topical compound : I think that proper use of the needle (correct positioning of the bevel "flat" on the mucosa), and pen-grip handling of the syringe (Wand, SlleperOne, QuickSleeper) and computer controlled injection, are three basic factors allowing a totally pain-free anesthesia : see for more about that our pedagogic article about pain-free palatal anesthesia...in French...

I hope this will help.

If you need further details, please let me know : if you provide me with your email details, I can send you a lot of articles (with good iconography demonstrating the art of doing).

Theirry, I just got back from a conference myself though not on MAS! Your very detailed explanation of intradiploic anesthesia (hadn't been aware of that term before) was very helpful. I have to try that technique! I will have to look for a QuickSleeper delivery system. When I get it I will let you know. My email is [email protected]. Send me an email and I will have yours and I can contact you directly if i have particular questions.

I've been looking at the Sixou articles.

I give you below some more information on anesthetizing teeth with MIH : during the recent (April) congress of the French Pedodontics Society, a team from the university of  LILLE (northern France, near Belgium) communicated on the subject . Here are the main facts:

22 patients aged 6 to 13 years, with a MIH and requiring a conservative treatment on mandibular molars were included in the study. Each patient had a mucous anesthesia followed by an osteocentral injection of articaine with 1/100 000 or 1/200 000 epinephrine, using the QuickSleeper S4 injection system (DHT ®). 

Results:  successful anesthesia was obtained in 91% of cases (20/22). It allowed immediate dental treatment (immediate onset) right at the end of the injection. However, the authors explained that they could not be sure on the failures, as the notion of failure remains difficult to assess because the anxiety linked  to dental care that characterizes these patients,  influences strongly their feeling.

They concluded that the use of the Quicksleeper S4 system for performing osteocentral  anesthesia, sometimes associated with sedation, allows to get very quickly an effective analgesia. This study shows the interest of osteocentral anesthesia performed with a controlled rotary injection system in treating children with MIH. As usually, they said that a study on a larger sample more is needed to confirm these preliminary results.

Reference :

Laumaillé M, Borowski M, Dehaynin E,  Delfosse C, Trentesaux T. Apport de l’anesthésie intraosseuse pour les patients atteints de MIH. Le Fil Dentaire.2014 ; 94 : 34-8

Unité Fonctionnelle d’Odontologie Pédiatrique

Centre Hospitalier Régional Universitaire de LILLE (FRANCE)

In my opinion, in these cases (MIH) it is highly advisable to use an anesthetic formulation with a higher concentration in epinephrine (in France : lidocaine 2% with 1/100 000 or 1/80 000epinphrine (we do not have formulations with 1/50 000). This allows by the same way to reduce drastically the quantity injected .

 Bonjour Dr Collier. 

Je ne sais pas si vous verrez ce message, que je publie 2 ans après vos réponses ! 

Je rédige en ce moment ma thèse pour le diplôme de chirurgie dentaire sur le traitement des MIH. Et je suis très intéressée par vos réponses. Notamment sur la difficultés d'anesthésie des dents atteintes de MIH. Vous dites que l'analgésie est difficile à obtenir du fait d'un état permanent de pulpite chronique sur ces dents à cause de l'hypominéralisation. 

Auriez vous des articles à me conseiller, car je recherche des références bibliographiques sur ce sujet, qui justifierait scientifiquement de la difficulté d'obtention d'analgésie de ces dents. (Autres que par les retours/ressenties des dentistes)

Egalement, est ce que vous pensez que la MIH a un effet sur les canaux sodiques? Si on injecte la solution anesthésique, ne devrait elle pas simplement bloquer les canaux sodiques et permettre l'analgésie?

J'espère que vous verrez ce message. 

Je vous remercie par avance, 

Cordialement 

Clinically, the lesions of MIH are fairly large demarcated opacities of altered enamel translucency. The defective enamel is white-cream or yellow-brown in color. The opacities are usually limited to the incisal or cuspal one third of the crown, rarely involving the cervical one third. The intact enamel surface is typically hard, smooth and often hypermineralized following posteruptive maturation; the subsurface enamel is soft and porous. The MIH-affected FPM’s are sometimes hypersensitive to stimuli and may be difficult to anesthetize. It is believed that there is subclinical pulpal inflammation due to porosity of the enamel which could lead to hypersensitivity experienced by som individuals. In a study comparing the pulps of noncarious hypomineralized FPM to apparently sound FPM from MIH affected individuals, it was concluded that the changes were indicative of inflammatory changes. Caries progression is very rapid in FPM affected by MIH due to the porous enamel. It is further compounded by the fact that these affected children may avoid brushing because of sensitivity.

Hypomineralization of molars does not interfere with successful anesthesia. The 3-position blocking technique is the most indicated and due to the child's growing anatomy, the tilt widely reported in the books must be observed.

Fernanda - As. Berkant wisely noted, chronic nociceptive neural stimilation of hypomineralized tooth pulps can occur from deep carious incursion to thesse teeth, the resulting inflammation can produce a low threshold high frequency (chronic) neural stimulation that causes pthological function of the nociceptors in the dorsal horn of spinal cord. This produces the hyperalgesia of hupomineralized teeth and explains why many of them ar e so difficult to anesthetize.

Anatomical oosition should not intrrfer with the

Should not interfer with a mandibular block injection

I should have said “anatomical position of the tooth” in my previous statement.