2016 Glossary - 64
sequestration n: the process whereby necrotic bone
separates from native healthy bone and forms a sequestrum.
sequestrectomy n: removal of a sequestrum by surgical means.
sequestrum n: an island of nonvital bone that is separated from native healthy bone.
sessile adj: having a wide base of attachment; lacking
a stem; not pedunculated.
sextant n: generally, the sixth part of anything. In dentistry, it is a one-sixth subdivision of the dental arches. The anterior sextants are composed of the incisor
teeth and canines; the posterior sextants are composed of the premolar and molar teeth.
shade n: the color selected for a coronal or gingival
portion of a dental prosthesis (crown, bridge, or implant restoration).
shearing stress n: the stress induced in a material as a
result of sliding forces over 2 areas.
shelf, buccal n: the bony area of the mandible extended from the alveolar ridge distal to the mental
foramen to the external oblique ridge. This area is
covered by cortical bone and provides attachment
to the buccinator muscles. It has considerable resistance to resorptive changes and is considered a
primary stress-bearing area for a conventional complete mandibular denture or a mandibular partial
denture with a free-end distal extension.
shim stock n: a thin strip (8-12 μm) used to mark or
confirm the point(s) of contact on natural teeth, artificial teeth, or a restoration. It is used to facilitate
occlusal and proximal contact adjustment.
sialadenitis n: salivary gland inflammation.
sialagogue n: any substance or agent that stimulates
sialorrhea n: salivary flow more than the normal rate.
sinus n: a cavity or hollow space in the body.
sinus tract n: a communication between a pathologic
space and an anatomic body cavity.
sleeper n: slang for any osseointegrated dental implant fixture that is not in function.
slough n: the process of shedding necrotic tissue.
SNA angle n: acronym for sella-nasion-A point; in analysis of a cephalometric radiograph, it is an angle that
indicates the relationship of the maxillary basal arch
to the anterior cranial base. It denotes whether the
maxilla is in a normal, prognathic, or retrognathic
SNB angle n: acronym for sella-nasion-B point; in analysis of a cephalometric radiograph, it indicates the
relationship of the anterior limit of the mandibular
basal arch to the anterior cranial base. It denotes
whether the mandible is in a normal, prognathic, or
soft splint n: (1) a dental device (appliance), fabricated from a resilient material, such as flexible acrylic
or vinyl, which covers the upper, lower, or both arches to protect them from trauma or disclusion. An
athletic mouthguard is an example. Unlike its hard
counterpart, this appliance is used only for shortterm indications because of its lack of durability. (2)
A characteristic of a portion of an occlusal splint; generally, resilient acrylic placed on the intaglio surface
for comfort or increased retention.
soldering index n: (1) using a heat-stable investment
material to form a refractory cast in order to capture
the exact orientation of the units to be soldered that
were retrieved via a pickup impression; (2) fixing the
relative positions of units to be soldered through a
rigid connecting material. Fixation of this type is often used in conjunction with an implant analog master cast to accurately capture implant prosthetic unit
positions on their respective fixtures.
somatoprosthetics n: the art and science of artificial replacement of missing or deformed parts of
the body with medical-grade silicone, glass, and/or
acrylic. Often these prostheses are anchored to the
body through the use of osseointegrated implants
with clips, snaps, or magnets.
sonicate (sonicated, sonicating, sonication) v: application of sound energy to agitate particles in a solution.
Often used to create air bubbles through cavitation
in order to disrupt microorganisms.