Think pink – orthodontics a problem or solution to gingival recession. 6 MINUTE SUMMARY

orthodontics In summary

Join me for a summary looking at gingival recession in orthodontics, and whether it is detrimental or beneficial. This lecture was given by James Andrews, he explored the effect of orthodontics on the periodontium, an area under increasing interest within aesthetics to achieve the ideal ‘pink aesthetics’ with the increasing adult population receiving orthodontic treatment. His lecture was based on, is orthodontics good or bad for the gingiva?

What is the starting point ?

• Increase in adult orthodontics from 1970 by 800%

• 50% of adults have some element of periodontal disease

• Untreated adult population 51% dehiscence 37% areas of fenestration Evangelista 2010

Facial type and bone morphology Tunis 2021

• Dolichocephalic = narrow alveolus and elongated to compensate for vertical growth

• Brachycephalic = larger alveolus

• Dolichocephalic - Red flag patients

Tooth movement:

What happens when teeth move buccally?

• facial tooth movement Wennström 1996

• Reduced bucco lingual width

• Therefore, reduced free gingiva

• Increased risk only if tooth is moved out of the alveolar housing

What type of movement

• Tipping (uncontrolled) increase likelihood of recession Condo 2017

• Proclination causes recession, but inconclusive

• Thickness more relevant than final inclination Yared 2006

How to decide what to do?

WALA line – Will Andrews Larry Andrews ridge Andrews 2000

• Limit of labial bone – shape is coincident with the mucogingival junction, coincident with centre of resistance

• Upper incisors – located anterior 1/3 of alveolus

• Mandibular incisors – cantered within the alveolus

• Gingival recession did not increase in treatment orthodontic population with segmental mechanics Melsen 2005

Aligners any different?

• Association between non-extraction clear aligner therapy and alveolar bone deficiency and fenestration

• Presence of both fenestration and dehiscence

What do we do to correct extra-alveolar teeth?

If teeth pushed outside of cortical plate then retracted, what happens

• Monkey – moved teeth outside of bone for 8 months, then reposition within bone with appliances = repair bony dehiscence and fenestration

• Morten Laursen and Melsen 12 consecutive patients 2020

• Teeth moved towards the centre of the cortical plate = improvement in gingival height of depth decrease of 23%, the width with 38%

Intrusion

• Use of intrusion arch increases the thickness of the periodontal fibres 0.7 to 2.3 mm Melsen 1988

Gingival graft when to move teeth

• Free gingival graft – 6 weeks

• Connective tissue graft – 12 weeks

“Diagnose and treat each tooth no miracles shortcuts for good orthodontics” Peck 2017