1
Oral hygiene measures
When plaque is allowed to accumulate freely, there is an acute exudative
inflammatory response within 2-4 days of junctional epithelium. After 10-12 days
of persistent plaque accumulation, marked collagen destruction and a dense
infiltration of chronic inflammatory cells can observed in this zone. The clinical
changes of chronic gingivitis can be detected: redness, swelling, reduced resistance
to probing and increased tendency to bleed on probing or when the teeth are
brushed.
Apical advancement of sub gingival plaque cause separation of junctional
epithelium from tooth surface to form (pocket epithelium), which characterized by
formation and lateral extension of retepegs and by area of micro ulceration. As
soon as the destruction process extends apically to affects the alveolar bone and
fibro attachment of the root surface, periodontitis is said to have developed.
Periodontitis is characterized by loss of connective tissue attachment.
Dental plaque occupies the central role as the major etiological factor in the
pathogenesis of periodontal disease.
Chronic gingivitis is a condition that can be largely reversed by plaque
control, on the other hand, the loss of fiber attachment which is the principal
feature of periodontitis, is virtually irreversible and may lead eventually to tooth
loss.
Dental plaque
It is the non-mineralized, bacterial aggregation on the teeth and other solid
structures in the mouth, which is so tenaciously adherent to the surface and resists
removal by salivary flow or gentle spray of water across its surface. Approximately
70% of the volume of plaque is composed of bacterial cells. The reminder
comprises protein and extracellular polysaccharides, which act as matrix for the
cellular component. In addition, plaque contains small numbers of epithelial and
white blood cells that are derived from crevicular fluid.
The earliest deposit to form on a cleaned tooth structure is the acquired
pellicle, which is a structureless film of salivary glycoproteins selectively adsorbed
Preventive Dentistry
Fifth Grade
أ.م. ساهر سامي
2
to the surface of hydroxyapatite crystals. This formation of pellicle is accompanied
by bacterial colonization as microorganisms in saliva adsorbed to the pellicle.
After 3 or 4 hours, a thin layer of plaque, composed mainly of gram positive cocci
will be established. After 7 days, other different species become predominant.
In gingivitis, there are more than 200 different species occur, periodontitis is
caused by sub gingival down growth of those bacteria that are best able to evade
host defenses and survive in a low oxygen environment.
Dental calculus
Mineralization within plaque results in calculus formation. The inorganic
content of calculus (70-90%) is mostly crystalline amorphous calcium phosphate.
The organic content include protein, carbohydrates, lipid and various non-
vital microorganisms, predominantly filamentous ones.
Stain
It is caused by food substances such as tea, coffee and red wine, by tobacco,
by the products of chromogenic bacteria or by metallic particles. The pigments
become absorbed by plaque or pellicles.
Factors predisposing to plaque accumulation
1. Anatomical factors as:
a. Tooth malalignment.
b. Crowding.
c. Tipped or rotated teeth.
2. Dental (Iatrogenic factors) are often result of poor quality dental
treatment or treatment planning as:
a. Rough surface of restoration which accumulate plaque more readily
than a well-finished or highly polished restoration.
3
b. Overhanging or defective cervical margins of restoration act as
retention sites for dental plaque.
c. Sub gingival restoration margins which lead to greater plaque
accumulation.
d. Removable partial denture.
e. Fixed orthodontic appliance.
Factors modifying the inflammatory responses
1. Smoking.
2. Diabetes.
Smoking
Considerable research has established that the nicotine may have wide ranging
effect on the host’s immune and inflammatory status by causing:
a. Vasoconstriction of the periodontal and gingival microvasculature.
b. A reduction of neutrophil chemotaxis and phagocytosis.
c. A reduction of the ability of neutrophils to adhere to capillary walls.
d. In a dose-dependent manner: the production and release of cytokines such as
interleukin TNF and acute phase protein.
e. Reduction of the concentration of serum immunoglobulin, particularly in
subjects with early onset periodontitis.
Diabetes
Poor or unstable glycaemic control lead to an increase in advanced glycated
end products (AGEs) which are glucose- derived compounds that form when there
is a chronic elevation in blood sugars. (AGEs) link with receptors on macrophages
to up regulate the macrophages to release biological mediators of inflammation
such as cytokines.
4
Oral hygiene measure
1. Periodontal health education:
The objective of oral hygiene education is to produce a change in behavior, which
will result in a reduction of plaque accumulation through:
a. Dental hygiene advice.
b. Dietary advice.
c. Smoking cessation advice.
2. Plaque removal
We have different ways and methods to remove dental plaque:
a. Mechanical method.
b. Natural method.
c. Chemical method.
d. Professional method.
Mechanical method
1. Teeth brushing (manual)
We have different types of tooth brush:
Mixed bristles which characterized by different thickness of the bristles,
and so, this brush has double action due to thin and thick bristles.
Interlaced bristles with each other and this type is used for malaligned
teeth.
Flat surface brush (best and most used one).
Tufted dental brush, that used mainly for orthodontic and malalignment.
The tooth brush must be small (not large), soft bristles (not hard), rounded end
bristles (not sharp), bristles of nylon and flat in shape.
5
Design variation in tooth brushes include:
Dimensions of the head
The length, diameter and modules of elasticity of the filaments.
Number, distribution and angulation of the filaments.
Tooth brushing methods
They are categorized according to the direction of the brushing stroke into:
a) Vertical.
b) Horizontal.
c) Roll technique.
d) Vibration technique (Charters, Stillman and Bass)
e) Circular technique.
f) Physiological technique.
g) Scrub brush method
The recommended method of tooth brushing is determined by the individual
patient’s manual dexterity, motivation and oral hygiene. Also any method of
brushing that remove dental plaque effectively without harm to hard and soft tissue
is acceptable.
Historically, the most frequent used is the roll method. This, however, may
be one of the least efficient methods according to several studies with modification
in technique as attempt to cleans the sulcus, the Bass method was developed and
has become one of the more frequently suggested technique.
Roll (sweep) technique:
The brush is placed on attached gingiva close to the gingival margin of the
teeth with bristles pointing apically in 30-40 degree angle to the long axis of the
teeth then with a rolling or sweeping stroke, the brush is moved in a coronal
direction until the bristles make 90 degree angle with the tooth surface at the
occlusal edge of the teeth, only moderate pressure is applied and the movement is
repeated five to six times for each segment covered by the brush. From the lingual
6
and palatal sites, only few teeth can be covered by each movement of the brush.
Occlusaly, clean with horizontal stroke. The used brush is hard or medium.
Advantages:
Easy to learn.
Require moderate dexterity.
Disadvantages:
Does not clean sulcus area.
If hard brush is used carelessly, may produce damage to the gingiva.
2. Powered tooth brush
Used in specific patient groups:
a. With fixed orthodontic appliances.
b. Children and adolescents with a physical or learning disability.
c. Institutionalized patients.
The brush of the powered tooth brush tend to be more compact than those of
conventional manual brush. The bundles of bristles are arranged either in rows or
in circular pattern mounted in a round head.
The bristles are also arranged as more compact single tuffs, which facilitate
interproximal cleaning and brushing in less accessible areas of the mouth.