Perio Restorative Interface Flashcards
Restoring a tooth that is perio involved can cause failures because…
If placed in time of inflammation- tooth-restoration interface can become exposed after inflammation subsides
Except for emergency
Define disease activity
Presence of inflammation in the dentogingival complex not conductive to the maintenance of health
Inflammation can set when epithelial integrity is breached by pathogenic microflora and their metabolic products as well as result of trauma during the restorative peocedures
Disease activity and severity are influenced by host susceptibility and response, tissue characteristics, virulence factors of the microorganisms and iatrogenicity of restorations or prosthesis
Disease can advance to involve loss of connective tissue attachment with apical migration of the junctional epithelium and loss of alveolar bone
Even healthy periodontium can be affected by restoration of poor quality or other way around- high quality restoration can fail due to poor periodontal health and maintenance
What is biological width
It is the vertical dimension of the dentogingival complex (from the top of the interdental bone to the base of the sulcus, which comprises sulcular depth, the junctional epithelium and the connective tissue attachment.
Preserving this distance is necessary for a healthy periodontal attachment
It is usually around 2.04 mm but clinically we say it is 3 mm
It provides natural seal around the tooth, protecting from the unchecked ingress of pathogenic organisms in to the connective tissue
- it is the primary defence barrier
If restoration margin is extended into the biological width, body will try to re establish it so there will be persistent gingival inflammation within the attachment apparatus.
Usually it is G - and anaerobic bacteria that thrive there and cause progression of persistent inflammation
Clinically - 3 mm from the crown margin to the crestal bone is needed for maintaining periodontal health
The margin of the restoration should never be more than 0.5 mm subgingival
Gingival biotypes
Can influence restorative treatment outcomes
It can be either thick and flat or thin and scalloped
Thin scalloped gingivae are more prone to recession
What is zenith
Zenith point is the height of contour of the gingival scallop
Zenith point is distal to the long axis of the central incisors and canines, while on the lateral incisor the zenith is coincident with the long axis
Explain few points of gingival arcade
Height of gingival margin of the central incisors and canines should be at the same level
Lateral incisal gingival margin height is up to 1 mm incisal to the line joining the height of the gingival margins of central and canines
Most incisally positioned papillae is between centrals, papillae gradually assumes a more cervical position posteriorly
Gradual decrease in height of the gingival outline from the centrals backwards
Contact areas and interdental embrasures
Biggest between centrals (50% of the length) then between central and lateral ( 40% of the length of central incisor) then between lateral and canine (30% of the central incisors)
Paipllae contour - the distance from the gingival margin to the alveolar crest is 3 mm on labial; and from the interproximal papillae to the bone crest is 5 mm - therefore it is important to position contact point relative to the interproximal alveolar crest for reconstructing and maintaining papillae to avoid black triangle
So if distance is bigger- bigger the black triangle
Importance of attached gingivae
It is important to minimize the risk of gingival recession and to increase PT comfort when doing OH
The width of the attached gingivae is not interfering to periodontal health in presence of good OH ( e.g in perio)
Hard tissue- tooth dimensions
Prosthetic crown contour should appropriate tahta of the natural tooth
However, in cases like median diastema - mesiodistal dimension might be increased
If the roots of the adjacent teeth are in close proximity then there will be less room for increase of mesiodistal dimension
Hard tissue- tooth
In facio-lingual direction dimension of the prophetic crown should not be increased more than 0.5 mm from the gingival margin as it may induce plaque retention
The location of interproximal area determines the height of contour of the interdental papillae, as well as the dimensions of the incisal and gingival embrasure
Emergence profile of the restoration as it emerges from the gingival margin should be straight or flat for the first 0.5 mm of the restoration to maintain healthy gingival tissue.
Emergence angle-15°
