The document discusses the history and evolution of tooth replacement methods. It describes how early replacements used ivory, bone, silver and gold dating back to 700 BC. In the 18th century, dentures were made of porcelain and later vulcanized rubber. The discovery of acrylic resin in the early 20th century revolutionized prosthodontics. Implants were also introduced as an important milestone. New resins with better properties than acrylic have since been developed. The document outlines different types of prosthodontics and causes of tooth loss that prosthodontics addresses.

1. Dr Anmol Asghar Ali
BDS, PG Oral Implantol ADA Certified
PG DIP:Orthodontics &
Dentofacial Orthopadics USC Spain

2.  • Replacements of lost teeth have been
reported for thousands of years
 • 1 st dentures were 700 BC from ivory &
bone, Silver, gold,
 • In 1774, dentures made from porcelain •
The real breakthrough came when vulcanized
rubber was discovered

3.  The discovery of acrylic resin is the next
major revolution in prosthodontics In 1901,
in Germany, Otto Röhm described his
acrylate synthesis work in “Polymerization
products of acrylic acid”, his doctoral thesis
then later patented the process in 1915.
 Another important milestone in tooth
replacement was the introduction of
implants.

4.  Acrylic resins dominated dentures technology for several
decades. Due to their many disadvantages, new classes of
resins, which promise better quality, constantly appear.
Mechanical properties of acrylic resins, including fracture
behaviour, water absorption and mechanical strength
degradation caused by the exposure to saliva of classical heat-
cured acrylic resins compared to alternative urethane-based
light-cured resins, were carried out. The allergy potential of
acrylic resins was evaluated by in vivo and in vitro tests. New
choices of resins, like thermoplastic injected resins, light-
cured or milled high-performance polymers, with better
properties compared to acrylics, suitable for dental
applications are being presented.

5.  1. Fixed prosthodontics
 2. Removable prosthodontics
 a) complete denture prosthodontics
 b) partial denture prosthodontics
 3. Implant prosthodontics
 4. Maxillofacial prosthetics

10.  • Traumatic injuries
 • Caries
 • Periodontal diseases
 • Cysts, malignancies and tumors
 • Radiation therapy for tumors
 • Grossly malaligned teeth
 • Iatrogenic extraction
 • Congenitally missing teeth
 • Failure to erupt (impacted teeth)

24.  Following loss or extraction of teeth:
 The empty socket fills with clot and
 gradually replaced with new bone
 The bone around the socket reorganizes
 The mucoperiosteum gradually heals &
covers the healing socket
 The remodelling process results in a
rounded ridge like structure known as
the residual alveolar ridge ( RAR)

25.  The RAR plays a very important
 role in the construction of the CD

26.  Order I Preextraction
 Order II Postextraction
 Order III High, well rounded
 Order IV Knife edge
 Order V Low, well rounded
 Order VI Depressed

28.  Most rapid in the first 1 year after
extraction and can be as high as
4.5 mm / year.
 After healing of residual ridge,
annual rate of reduction in height
is about 0.1-0.2 mm in mandible
 Annual rate of reduction in height
is about 4X greater in mandible
than in maxilla.

29.  Maxilla
The resorbtion is upwards and inwards
(smaller)
 Mandible
The resorbtion is downward and outward
(wider)

30.  Significantly lower than that
produced by natural teeth
 Natural teeth can produce forces
up to 175 pounds but usually 40 to 50 pounds
 Denture wearers: the average force
was in the region of 22-24 pounds
in the molar-bicuspid region

31.  CD wearers are able to generate
forces that are only 10-15% of
those with natural teeth