Aging of the Occlusion: What Should We Know? Daniela Garib
Life expectancy most countries 75-90
Long term changes in adults
· Males forward rotation, females backwards rotation Behrents 1984
· Arch length decreases
· Increase in crowding
· Limited study follow up
Study by Daniela to investigate up to the age of 60, not previously done in orthodontic literature Massaro 2018 AJODO
· Initial sample age 13 -17 second sample age 60
· Study sample 22
Findings
· Increase in crown height 0.5-3mm, due to passive eruption and gingival migration
· M-D tooth size decreased 0.3mm
· Mandibular incisor crowding increased 2.5mm
o Due to reduction in arclength, direct relationship
o Possible boned retainer in normal occlusion
· Maxillary incisors crowding of 1mm (small)
o Arch length reduction of 3.5mm
o Explanation, upper incisors upright to resolve the reduction in arch length
· Overbite reduction
o Due to late mandibular growth
· Upper 7s upright, age 13 distally tipped, age 60 upright
· Patient satisfaction age 60 – satisfied
o Concerns relate to colour
o No desire for orthodontics
3d superimposition on aging models Garib 2021 AJODO
· Lower arch 13 landmarks of the gingival aspect
o Incisors retract
o Molars medialise
o Premolars lingually tip
· Maxillary arch Garib Orthodontics and craniofacial research
o 6 landmarks investigated , including 2nd, 3rd palatal rugae
o Reliable in 5 year interval
o Unreliable in 40 year intervals – likely due to changes in palatal rugae
Cephalometric soft tissue changes
· Decreased in NLA
· Upper and lower lip retrusion
· Reduction in upper lip thickness
· Soft tissue nose and chin increased
· Upper incisor show decreased 4mm in total, 1 mm per decade
Conclusion
· Occlusion is the most stable component when compared to skeletal and soft tissues
