Tooth Removal in the Leopard Gecko and the de novo Formation of Replacement Teeth

Brink, Kirstin S.; Henriquez, Joaquin; Grieco, Theresa M.; Campo, Jesus Rodolfo Martin Del; Fu, Katherine; Richman, Joy M.

doi:10.3389/fphys.2021.576816

Cited by 9 publications

(24 citation statements)

References 41 publications

(79 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Animals ranged in age from 1-3 years post-hatching (Table 1). The methods of removing plucking out or enucleating second generation teeth are as published (Brink et al 2021)(Fig. 1A-G).…”

Section: Methodsmentioning

confidence: 99%

“…When teeth were plucked, the immature teeth form deep in the tooth field but once they have formed a substantial crown complete with the enamel cap, these teeth have migrated out of the tooth field. There are never teeth of the same stage beside each other, but neighbouring teeth are arranged in diagonal rows or zahnreihen according to maturity (Brink et al 2021). We also never saw a group of teeth erupt at exactly the same time which would have happened if there was a simultaneous release from inhibitory signals.…”

Section: Comparison Of Osborn's Zone Of Inhibition Relative To the Ph...mentioning

confidence: 99%

“…We previously showed that animals recover the normal dentition within 3 months of removing the unerupted, second generation teeth. However, in this previous study (Brink et al 2021) we had not followed the animals for longer than 3 months. Instead attention was focused on the cellular events that occurred after tooth removal and the contribution of epithelial stem cells to the next generation of teeth (Brink et al 2021).…”

Section: Introductionmentioning

confidence: 98%

“…However, in this previous study (Brink et al 2021) we had not followed the animals for longer than 3 months. Instead attention was focused on the cellular events that occurred after tooth removal and the contribution of epithelial stem cells to the next generation of teeth (Brink et al 2021). In the present study we combine the selective tooth removal experiments with long term tracking of tooth shedding.…”

Section: Introductionmentioning

confidence: 98%

“…The leopard gecko is a good model in which to carry out experimental perturbations. We have developed methods to selectively remove a set of unerupted teeth to offset the timing of tooth initiation, eruption and shedding in the centre of the jaw (Brink et al 2021). We previously showed that animals recover the normal dentition within 3 months of removing the unerupted, second generation teeth.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Evolutionarily conserved waves of tooth replacement in the gecko are dependent on local signaling

Brink

Cytrynbaum

Grieco

et al. 2022

Preprint

Self Cite

View full text Add to dashboard Cite

Tooth replacement is a conserved process in vertebrates extending back to the ancesters of modern fish, amphibians, reptiles and mammals. The patterns in dinosaurs and reptiles have been described by scientists as regular waves going from posterior to anterior of the jaws where every other tooth is replaced. The patterns suggest that local and possibly jaw-wide communication betwen tooth families is involved. The tooth replacement process is not well understood since there are few animals with acessible dentitions. In this study we study leopard geckos in which tooth succession occurs repeatedly throughout life thus giving multiple opportunities to track the process. In addition we performed 2 types of experiments that unlaterally interfere with tooth replacement. Animals were followed using serial wax bites for 2-3 months prior to unilateral, selective tooth removal and then for 7-9 months after surgery. The data on tooth presence or absence was transformed mathematically to capture the time between eruption events of the successional tooth at the same position. Relationships between neighbouring tooth families and across the midline were measured to look for relative phase symmetry or asymmetry. We then tested 5 alternative models of tooth replacement to explain the observed patterns of recovery. The selective removal of unerupted second generation teeth showed that there were no signals passing back to the tooth forming field. The pattern of tooth eruption was not only re-established but it was in phase with the surrounding unperturbed tooth locations, as reflected in the nearest-neighbour diagonal lines. In animals that had permanent ablation of the dental lamina, the cycling of teeth anterior and posterior to the gap was unaffected refuting the presence of directional factors that pass from one tooth family to the next. Finally we compared the patterns of replacement between geckos and alligators using Edmund, 1962 data. The general nearest neighbour staggered patterns were conserved but the alligator had very slower rates of replacement in the posterior jaws. The geckos maintain similar cycling frequences across the jaws. In conclusion, we reject the Osborn model of zones of local inhibition and Edmunds wave-stimulus theory.Instead propose that teeth themselves are cycling and that these cycles regulate the staggered timing of tooth initiation. We also showed that once established, the local control of tooth replacement is very resilient to environmental perturbations as long as the dental epithelium is retained.

show abstract

“…Animals ranged in age from 1-3 years post-hatching (Table 1). The methods of removing plucking out or enucleating second generation teeth are as published (Brink et al 2021)(Fig. 1A-G).…”

Section: Methodsmentioning

confidence: 99%

Section: Comparison Of Osborn's Zone Of Inhibition Relative To the Ph...mentioning

confidence: 99%