Local predisposing factors Flashcards
Local predisposing factors contribute to the disease initiated by bacterial plaque by?
- increase plaque retention
- interfere with perfect plaque removal
- induce direct damage to the tissue as food impaction & habits
What are the characters that dental restorations & RPD should fulfill to maintain the periodontal health?
- gingival margin of restoration (position & nature and with no overhanging margin).
- contour of restoration.
- materials used.
- occlusion.
- restorative procedures.
- design of RPD.
The restorations margins should be
round & smooth with polished surface
least effect on the periodontium (restoration margin type)
Supragingival
greatest biological risk (restoration margin type)
Subgingival
Subgingival margins of restoration can contributed to periodontal diseases by:
(Give reasons)
- More accumulation of plaque (considered a plaque retentive area).
- Represent an inaccessible areas for both proper plaque control by the patient and even for scaling by the dentist.
- Violation of the Biologic width.
Thus may lead to severe gingivitis & even pocket formation.
☻ Overhanging margins contribute to the development of periodontal disease by:(Give reasons)
- inhibiting the pt’s access to remove plaque. (i.e. interfere with perfect plaque removal)
- changing the ecologic balance of the gingival sulcus to an area favors the growth of disease-associated m.o (i.e. Change the balance of the gingival sulcus area in favor of the growth of G –ve anaerobic species instead of G +ve facultative species).
☻ Removal of overhanging (Mention results)
more effective plaque control, leading to
reduction of gingival inflammation
small increase in alveolar bone support
Periodontal complications associated with orthodontic therapy
☻ The presence of orthodontic appliance :
1. favor plaque retention.
2. modify plaque composition with increasing gram –ve m.o. such as
P. intermedia,
P. melaninogenica,
A. actinomycetemcomitans.
☻Factors leading to food impaction:
- uneven occlusal wear
- open contact point
- morphological abnormalities
- improper constructed restorations
- excessive anterior overbite
Iatrogenic Factors
Def:
Faults in dental restorations & prosthesis.
Overcontouring leads to:
Undercontouring leads to:
Overcontouring leads to:
1. Plaque accumulation increased.
2. Prevention of the physiologic self cleansing mechanisms from adjacent muscles of cheek, lips and tongue.
Undercontouring leads to:
1. Lack of protection of gingival margin during mastication thus affecting gingival health.
2. Open contact results in food impaction
From the periodontal point of view, Glass ionomer restoration & porcelain are more acceptable, as they seem to retain less plaque. (Give reasons )
- Fluoride that constantly leak from glass ionomer cement prevents the attachment of bacteria to the pellicle, and it interferes with the metabolism & growth of bacteria.
- The highly polished surface of porcelain inhibit plaque formation and facilitate its rapid & easy removal too.
☻ Gingival recession occur in case of:
- prominent roots in the arch (buccal or lingual version) fenestration & dehiscence.
- high frenum attachment.
- narrow attached gingiva.
☻ Failure to replace missing posterior teeth (ex. missing lower 1st molar) may adversely affect the periodontium:
- extrusion of max. 1st molar (opposing molar).
- mesial drifting & tilting of mand. 2nd & 3rd molars.
- The distal cusps of the mand. 2nd molar extrude & act as plunger cusp wedge between the max. 1st & 2nd molars & open the contact between the upper 1st & 2nd molar by deflecting the max. 2nd molar distally food impaction.
