The canine protocol
Peridontitis is one reason why anyone would want to transplant the microbiome from the mouth of one dog to another. These authors started out with a super donor dog with all of her teeth and no gum disease. The recipients were test beagles with dental issues. Each of the recipients received bacteria from the mouth of the super donor. Scroll down to the human section . This 2021 publication claims that their canine based [1] protocol is the only one in the world.[2]
Healthy donor:
4-y-old periodontally and systemically healthy female beagle dog with all 42 teeth was enrolled as the healthy oral microbiota transplant donor
Treatment groups:
- Eighteen systemically healthy 2- to 7-y-old female and male beagle dogs with naturally occurring periodontitis with at least 32 teeth were included in the study and randomly assigned to a test (n = 9) or control (n = 9) group by block randomization.
- Periodontitis severity was determined after inclusion and randomization into experimental groups to avoid allocation bias.
- Probing pocket depths (PPD), bleeding on probing (BOP) scores, and plaque index (PI) scores were recorded for both groups at 4 time points: 2 wk before OMT (week –2), at OMT (baseline), 2 wk after OMT (week 2), and 12 wk after OMT (week 12) by calibrated examiners under general anesthesia. Animals were housed at the
- To prevent any unintended transmission of oral microbiota, dogs were separated from each other during the study period.
- To reduce periodontal inflammation, all dogs in both groups received full-mouth supra- and subgingival debridement using sonic scalers and hand instruments as well as full-mouth glycine powder air polishing (GPAP) 2 wk before baseline. GPAP seems to be a new addition to air polishing with baking soda. Interesting as baking soda is used a cheap version of tooth paste.
- Each supra- and subgingival tooth surface was treated with GPAP for 5 s and each mucosal surface (buccal and labial mucosae, lingual and buccal alveolar mucosa, floor of the mouth, tongue, and palate) for 1 min. At baseline, this procedure was repeated except for the donor dog.
- To further suppress the resident oral microbiota, additional subgingival and oral irrigation with 0.1% NaOCl was performed for 5 min. Then, NaOCl was inactivated by subgingival and oral rinsing with 23 μM buffered sodium ascorbate for 10 min. Dental Economics compares iodine and chlorine based mouth rinses as antimicrobials.
The Oral Microbial transplant
- The donor microbiota was collected prior to mechanical debridement from supragingival biofilms of all teeth and mucosal surfaces using a hand curette and a cotton swab under general anesthesia at week 2.
- At baseline, the donor dog was sedated and supragingival biofilms from all teeth The samples were pooled and suspended in sterile reduced transport medium.
- An aliquot was reserved for microbiome analysis at each visit.
- The collected oral microbiota was dispersed by vortexing and used immediately for transplantation to 1 dog of the test group.
- Test dogs were inoculated with OMT by continuous subgingival and oral irrigation over a period of 10 min. The biofilms from the other side of the mouth were analogously collected on the next day and used for transplantation to a different test dog. This general procedure was repeated on pairs of test dogs over an approximately 18-mo period,waiting a minimum of 3 mo between harvesting/transplantation procedures to allow for the reestablishment of the biofilm
The Amazon.com version of the Vet hand curette looks like the product on the left. The same “hand curette” search of Amazon retrieved and “ear curette” for earwax removal.
The ear wax curettes might also work better than cotton swabs for the removal of mucosal biofilms. They may also be less dangerous for the donor child.
The human protocol [2]
- On the day of collection the donor refrains from oral brushing their teeth and other forms of oral hygiene.
- Supragingival plaque samples would be collected from four sites (buccal surface of maxillary central incisor, and lingual surface of mandibular central incisor and mesio-buccal surface of maxillary molar using a sterile dental curette.
- pooled plaque sample would be vortexed in 200μL of phosphate buffer solution and then samples would then be immediately transported to the Oral Microbiology Laboratory for inoculation in to the flow cells,
- A protocol for chewing of inert gum, spitting after two minutes and chewing on inert gum for another 2 minutes followed by sitting was included in this publication. [2]
- The sample (100 μl) is to be mixed with 1 ml of 25% modified version of Artificial Salivary Medium (ASM) before inoculation. The ASM includes the following components: 0.50 g/L tryptone (Oxoid, Hampshire, England), 0.50 g/L neutralised bacteriological peptone (Oxoid), 0.625 g/L type III porcine gastric mucin (Sigma-Aldrich, Steinheim, Germany), 0.25 g/L yeast extract (Oxoid), 0.05 g/L KCl, 0.05 g/L CaCl2, 0.088 g/L NaCl, and 1mg/L haemin (Sigma-Aldrich). The solution was supplemented with 2.5mM DTT (Sigma-Aldrich) and the pH was adjusted to 7.0.
- Things got complicated with the introduction of sodium alginate hydrogels with dopamine in them for the transfer of human oral microbiome samples to mice. The authors also discussed the visco elastic properties of these hydrogels.
As a general note, the 2.5mM DTT may be what the first paper referred to as “reduced.” the high protein content of this mixture might favor the growth of Porphyromonas gingivalis.[1] The authors of the proposed Australian study kept reiterating how this was the first of its kind in the world. There are so many foods that tend to stick to the teeth that may favor the growth of one set of microorganisms versus others…
Discussion
“To the best of our knowledge, OMT for the treatment and prevention of oral diseases has not been established anywhere in the world. OMT therapy may provide alternative tool to overcome poly-microbial oral diseases that are typically recalcitrant to treatment or prevention such as dental caries and periodontal disease. Our approach represents several strategic advantages at each step”
References
- Beikler T, Bunte K, Chan Y, Weiher B, Selbach S, Peters U, Klocke A, Watt RM, Flemmig TF. Oral Microbiota Transplant in Dogs with Naturally Occurring Periodontitis. J Dent Res. 2021 Jul;100(7):764-770. Free article
- Nath S, Zilm P, Jamieson L, Kapellas K, Goswami N, Ketagoda K, Weyrich LS. Development and characterization of an oral microbiome transplant among Australians for the treatment of dental caries and periodontal disease: A study protocol. PLoS One. 2021 Nov 29;16(11):e0260433. Free article
