Basics of prosthetic dentistry
Prosthodontics – it is a dental
speciality that deals with
diagnosis, planning, treatment,
rehabilitation and maintenance of
the oral funcion, comfort,
appearance and health of the
patients with clinical conditions
associated with missing or
deficient teeth and/or
maxillofacial tissues using
biocompatible substitutes.
Divisions
• Fixed prosthodontics - deals with restoration of teeth using crowns,
bridges, onlays, inlays and veneers.
• Removable prosthodontics - replacing the teeth and soft tissues with
a non-permanent prosthesis that can be removed, complete or partial
dentures.
• Implant prosthodontics – using implants that are interfaced with the
bone of the jaw to support dental prosthesis such as crown, bridge,
denture.
• Maxillofacial prosthodontics – deals with defects or deficits of the
face, jaws and surrounding soft tissues that may have occured due to
development, trauma or diseases.
Causes of teeth loss
• Periodontal diseases
• Dental caries
• Congenital missing
• Trauma
• Surgical procedures (on demand)
Consequences of teeth loss
• Anatomical loss of ridge volume – both height and width
• Physiological – chewing efficiency is decreased, drifting and
overeruption of the teeth, temporomandibular joint complications,
speech problems
Aesthetic consequences
Cosmetic impact of tooth loss may lead to psychological effects and:
• decreased facial heights (vertical dimension loss)
• ptosis of the chin and rotation forward (witch’s chin)
• Increase in the numer and depth of face lines
Terminology
• Dentate (dentulous) – condition in which natural teeth are present
• Edentulism (edentulous) – without natural teeth
• Partially edentulous – one or more teeth are missing
• Completely edentulous – all natural teeth are missing
Solutions
• Prosthesis – artificial substitute for missing natural teeth and adjacent
tissues, usually made of metallic and/or acrylic materials
• Aims of prosthesis construction – to replace missing teeth and restore
the masticatory function, to correct facial deformity caused by teeth
loss, to correct the speech, to maintain the oral and facial structures
in healthy conditions
• Division: partial denture/complete denture, removable/fixed
+ single artificial
crowns
Maxillofacial
prosthesis
• Replacement of the missing organs of the
stomatoghnathic system such as eyes, ears,
nose, lips etc. or part of them such as part of the
mandible, part of the tongue
Implant
prosthesis
• Branch of prosthodontics
based on the replacement of
missing teeth and/or
associated structures by
restorations that are
attached to the dental
implants
• Dental implants are medical
devices surgically implanted
into the jaw
Part 2 - physiology of chewing system, human
dentition, characteristic signs
Mastication
• It is a sensory-motor activity aimed
at the preparation of food for
swallowing, involves activities of the
facial, elevator and suprahyoidal
muscles and tongue. These activities
result in patterns of rhythmic
mandibular movements, food
crushing and manipulation.
• Saliva facilitates mastication,
moistens the food particles, makes a
bolus and assists swallowing.
Functions of mastication
• Enables bolus to be easily swallowed
• Enhances digestibility of food by decreasing the size of particles to
increase the surface area
• Initiates digestion with saliva
• Stimulates gastric juice secretion
• Prevents irritation of GI system
Process
• Convergent („come
together”) movements
• Most food is firstly crushed
by vertical movements and
then is sheared by lateral
to medial movements
• Once the cusps
interdigitate, the ridges of
the cusps shear the food as
the mandibular teeth move
across the maxillary teeth
Bite force
• The forces that are exerted on the teeth
and jaws are large and physiologically
significant
• Bite force during mastication is about 515kg and it varies according to the food
texture
• We can measure the bite pressure with
gnathodynamometer with a maximum
pressure of 50kg that can be recorded
Dentition
• Is based on:
• arrangement of teeth in the dental arch,
• types of teeth,
• characteristics of the teeth,
• total numer of teeth present
• dental formula (system for summarizing the number of each type of
tooth),
• structure of the teeth.
Human teeth are characterised by the
following features:
• Thecodont – socketed teeth, articulated with their root in dental
sockets in the dental arch
• Diphyodont – two sets of teeth (milk/decidous and permanent)
• Heterodont – different types of teeth (different morphological
structures and functions)
Types of teeth according their shape and
function
• Incisors – chiseled, flat and sharp with single root, function – cutting
• Canines – conical, single root, function – tearing
• Premolars – bicuspid, one or two roots, function – crushing and partly
chewing
• Molars – square, 2 or more roots, function – grinding and crushing
Thank you
Jakub Sepetowski