Azithromycin and Whitening

Azithromycin – The Final Ecological Solution?

I have been of the assumption of late that the once “trending” use of antibiotics as a form of adding a “sledgehammer” to the healing and repair process was defunct. I was also concerned about some of the low dose, long term prescriptive practices where patients were taking pills for up to six months. Consequently I was glad to see that this fashion appeared to be less intense as once it was. My assumption has recently been challenged in New Zealand both by what I have seen anecdotally in practice and the research I have since undertaken.

I was never convinced by the clinical outcomes I saw from other methods in antibiotic or antimicrobial forms. I was shocked, moreover, by their cost in relation to their benefit and the commercial imperative driving them forward. However, Azithromycin appears to have key features that have made me listen to the facts and question them still further. I am inclined to reconsider anything thing which is low dose/exposure/cost and manageable regime with a beneficial outcome when used in combination with effective and appropriately guided non – surgical periodontal treatment.

Azithromycin first came to my attention when discussing periodontal treatment with my New Zealand dentist colleagues who raved about its efficacy. I am always suspicious of quick fixes and over use of antibiotics but the single course of 500 mg daily over 3 days made me reappraise my position and further enquire.

What is Azithromycin?

Azithromycin comes from the Macrolide group of antibiotics being used extensively in medicine for the treatment of a wide range of infections but is also effective against common periodontal pathogens. It has additional immune-modulating/anti -inflammatory effects making it different to the Amoxicillin/Metronidazole combinations which don’t. The later are also used in longer regimes (7 days verses 3) and with 12 times the dose amount.

Azithromycin is; 1

  1. A synthetic derivative of Erythromycin.
  2. 300 times more stable in acid pH then Erythromycin.
  3. Less likely to cause gastro-intestinal upsets and therefore has better patient tolerance.
  4. Able to penetrate in high concentrations into tissue (via fibroblasts and neutrophils) and phagocytic cells allowing 2 targeted routes to infected sites.
  5. Able to be taken once daily for 3 days without regard to meals.

Azithromycin has also be shown to help manage periodontitis by reduce bleeding and increase wound healing in recent studies when used in combination with mechanical debridement 2

Now I am not usually a fan of protocols if you’ve read my previous posts but upon reflection it is important to have regime which reflects the need when to prescribe such combination treatment and for it to be more formalized whilst being refined as new evidence and experiences appear.

Towards an Azithromycin protocol

Protocol for the new patient

As a result of his clinical experience, research and observations Hirsch describes the protocol for the advanced/aggressive/refractory case as: 3, 4, 5

Initial Consult OPG – P/A’

Prescribe Azithromycin 500 mg x 3 – 1 taken daily

Pre Treatment phase

Start prescription 60 minutes (Initial removal of interdental and supra plaque retention factors/biofilm and OH phase – added by MJ and NV)

4-6 weeks

Assessment/ Initial treatment phase 90 minutes


Treatment phase

5 monthly appointments at 45 minutes

Review phase @ 6 months OPG P/A’s

Non responding supportive periodontal therapy/maintenance relapse

Hirsch describes the non-responding cases.

Identify/assess as non-responding – OPG P/A’s

Prescribe Azithromycin 500 mg x 3 – 1 taken daily

Pre Treatment phase

Start prescription – 60 minutes (Initial removal of interdental and supra plaque retention factors/biofilm and OH phase – added by NV/MJ)

Then leave 4-6 weeks

Assessment/ Treatment Phase

2 x 90 minute appointments for re assessment and non-surgical periodontal therapy within 24-48 hours (disinfection) – added by NV/MJ


5 monthly appointments at 45 minutes

Review phase @ 6 months OPG P/A’s

Non responders refer to Periodontal Specialist 


  1. L D Abby & M V Martin (2004) Azithromycin and dentistry – a useful agent? BDJ, 197 ; 141-143.
  2. M Danesh-Mayer (2012) Pockets, pus and periodontitis Non – surgical treatment strategies. Australasian Dental Practice: July/August, p56-57.
  3. Hirsch et al (2012) Azithromycin in periodontal treatment: More than an antibiotic. J Periodontal Res Apr;47(2): 137-48.
  4. Hirsch R (2010) Periodontal healing and bone regeneration in response to Azithromycin. Aust Dent J. Jun;55(2):193-9.
  5. Hirsch R (2011) Azithromycin and periodontal treatment, http;/

Doing the White Thing?– Reviewing and Changing my Practice in the Light of Evidence, Experience and Reflection.

Beautiful smile and white teeth of a young woman. Matching the shades of the implants or the process of teeth whitening.


I must confess I am not really that smitten on whitening and that aesthetic dental hygiene practice is an anathema to me. I put it down to my seniority ( age ) and a stubborn streak in me which maybe change adverse but perhaps more so a reluctance to be seen any more than a dental disease prevention expert. This is not to say I haven’t been on whitening courses, I have worked for Philips UK as a Key Opinion Leader and have been a very, very small party to their early journey after they bought the tooth  whitening company Discuss Dental and also the training that took place subsequently. I have also been very aware of various controversies linked to the whitening industry whilst in the UK and when returning to New Zealand I felt a huge sigh of relief to get aware from it all. I was however very quick to discover it’s less strictly regulated presence in the southern hemisphere.  My challenge was to either avoid it, dabble in it lamely or embrace the health and well-being benefits of it to the patient and, in turn, the professional and financial rewards to me as its clinical deliverer.

Current Situation

The previous and very capable dental hygienist used a combination of tray systems, both night and day. They occasionally used a in chair 35% Carbamide Peroxide (CP) gel for 30 minutes, a 22 % CP for 60 -90 minutes a day and a 16% CP take home  to use at night system. They were very confident about their results. I previously used a 40% in – chair light /heat activated system in Wellington successfully, similar to what I initially used in the UK, back in the days before regulations brought change. I must confess that my preference to the in-house system has changed out of necessity as my current practices aren’t equipped or orientated towards that technique. In a big way I am glad of this because 40% Hydrogen Peroxide (HP) at 2-3 x 10 minute exposures, with the hassle of applying the light, liqui-dam, lip retractors and aspiration plus the risk of gingival chemical burns and sensitivity “zingers” at that strength was ever-present. To add to this the expectation and the price of the procedure to the patient was also at the back of my mind and probably theirs too.  It all seemed a little hit and miss to me as trays and gel were needed to continue the process after anyway so why not just stay with tray systems night or day alone? I am currently contemplating creating a protocol for both day and night systems, considering the products we have and how to employ and deliver them in my current practice now. My dilemma and reflection focuses around my personal experiences, quality research and the “here say” of my current dental colleagues, some who believe that the higher concentration gels, 35% CP,  are bad for the pulp and increase the risk of non-vital teeth, others who believe the night systems are better tolerated than day systems and vice versa. This may lead to contradiction, confusion and perhaps less effective practice. I want to create an evidence based protocol that can be used in both clinics and modified when new research or better materials appear. My protocol decision-making will centre on recent quality research and also the clinical experience of colleagues and myself as well as past feedback from my patients. I use Polawhite products where I practice see


All my colleagues are agreed on night systems being 16% CP. The debate is whether 22% CP at 60 – 90 minutes or 35% CP at 15 minutes per day is more appropriate. In my experience patients when given the choice prefer day systems to night systems for a variety of reasons. I also prefer 35% CP short exposure based upon length of exposure, bulky trays in my mouth overnight and the risk of not being in control of the process. Patients have fedback to me the need to be in control of the process and I am happy to demonstrate and see them also apply the gel to the tray surfaces to confirm understand of what they need to do. I have decided also persuade them to be with me whilst the trays are in situ in my surgery for 15 minutes if 35% is chosen and a proper brief with printed handout is read and understood, as well as the process itself. I feel confident and comfortable with this process as the client experiences day whitening, the length of time required, has the opportunity to question or ask advice and is undertaken within a controlled clinical environment. Therefore,  the higher percentage of gel requires the patient to be fully informed about the process, empowered to proceed and return within the week to review shade and feedback their experience. This is also done for the other systems too. I feel very comfortable presently this whitening management protocol benefits both operator and recipient.  Will the evidence bear me out?

Research and Evidence

Costa et al (2010) indicated that bleaching with 38% HP for 45 minutes causes irreversible pulp damage in lower incisors but not in premolars .  Also, CP contains HP at a ratio of 1:3. For example, a product with 30% CP has about 10% HP. HP breaks down faster than CP, so it releases most of its whitening power within 30–60 minutes. CP, on the other hand, releases about 50% of its whitening power in the first two hours and can remain active for up to six additional hours. This affirms to me that CP is the better option for a prolonged release and less irritating to the pulp and a less concentrated gel. 1 Goldberg et al (2009) concluded that:

  1. Bleaching causes small defects at the surface and subsurface of enamel. This was a surprise to me initially but is it significant for 15 minutes a day for a week or 2?
  2. The effects on pulp are more controversial and may be inconsistent. Nevertheless, chronic treatment with peroxides may be not safe, and this could be the case when such treatments are carried out in the absence of a sufficient level of control by dental surgeons, hence the training phase is essential in my practice! 2

Meireles et al (2009) states that higher CP concentration does not increase the longevity of the whitening effect of at-home tooth-bleaching agents. One year after bleaching, both treatment groups 16% CP and 10%CP,  had the same median tooth shade, which remained lighter than at baseline.3 Therefore all are similarly effective after a year.


I wasn’t aware of the concerns regarding enamel tooth surface change with the higher concentrations but  35% CP is advised for only 15 minutes daily which I feel can be better controlled after appropriate client training prior to use. This and a 1 week follow up and feedback is still an great option for clients who want less exposure and a quicker outcome despite the evidence that indicates a possible similar median shade  comparative to other products after a year and a risk of small enamel defects . My patients are also welcomed to use 22% CP  for longer exposure times and a reduced risk to enamel defects. This appears to be the preferred option considering the evidence. Using 16% CP for several hours at night may also need to be complimented with the option, if available, of a 10% CP product. I’ll look further into this. I will therefore use the 22% CP as the whitening preference. I am hoping that most of my patients won’t mind the time lengths required. If they do find it problematic then the 35% CP  is indicated for those who want a quicker outcome with less exposure but will be advised that there may be a small risk of enamel change if used incorrectly.


Take shade – Tray fit – Training in use of product – Confirm understanding – Read brief whilst product in place – Remove after 15 minutes if 35% CP – Keep in if 22% CP  for 60 -90 minutes  – 16% CP for night use only trays checked and verbal brief – All return after a week for review, feedback and shade check – Review after as required by patient.


  1. Costa et al (2010), Human pulp responses to in-officetooth bleaching 2008 :
  2. Goldberg et al (2009), Undesirable and adverse effects of tooth-whitening products:a review
  3. Meireles et al (2009), A double blind randomized controlled clinical trial of 10 percent verses 16 percent carbamide peroxide tooth-bleaching agents: one year follow up: J Am Dent Assoc. 2009 Sep;140(9):1109-17

Go Ahead - Feed the Animal

Yes, Bears do. (Can't speak for the Pope though.)

Whole Dental Health

My Ongoing First Person Living Publication Reflecting Both Personal and Professional Developmental Changes in the Life of a Client Centred Dental Hygienist

Dr. Danenberg

Nutritional Periodontist


Brewing techniques, beer and the ins and outs of running a small brewery in Northland NZ.

Pinotoriously Hoppy NZ

Pinot in all its glory, cool Kiwi craft beer plus shitz and giggles of course.

dharma shed

In the beginner’s mind there are many possibilities, but in the experts there are few – Shunryu Suzuki

The Science of Human Potential

Understanding how to be the best you can be. Professor Grant Schofield.


Conversations to take learning forward


History never really says "goodbye", it instead says "see you later".

Loire De Da - Old and New World Wine Adventures

The Land, It's People and their Wine

Off The Plot in Dorset - The Ongoing Journey

Abiding in a life rich in experiences from the leafy down lands of Surrey to the warmer climbs of Nelson

%d bloggers like this: