Page 855 - My FlipBook
P. 855
:
SECONDARY DENTINE. 865
perfectly satisfactory way at the present time ; and, besides, it does not
seem best to attempt to consider these entirely apart from the diseases
of the soft parts, for the reason that the one seems in many cases to be
directly dependent on the other. Some attempt at classification will,
however, serve the purpose of simplifying description ; I therefore give
the following
1st. Secondary Dentine.—A new growth of dentine more or less
regular in formation, excited by abrasion, decay, or other injury, by
which the dentinal fibrils are subjected to irritation at their distal ends.
2d, Dentinal Tumor within the Pulp-chamber.—An erratic growth of
dentine into the pulp-chamber united to the wall by a pedicle. The
structure is usually very irregular.
3d. Nodular Calcifications among, but not of, the Tissues of the Pulp.
—These are the irregular nodulated masses so frequently seen either as
very small stones or irregular masses. They contain many calcospher-
ites. These were considered with the soft parts for the sake of con-
venience.
4th. Interstitial Calcifications of the Tissues of the Pulp.—This is the
counterpart of calcifications elsewhere in the body, as in the arteries, etc.
5th. Cylindrical Calcifications of the Pulp, the tissues of Avhich are
probably in a state of fibrous degeneration. Usually seen in the pulp-
canals.
6th. Osteo-dentine.—Erratic formations showing; both the lacunse of
bone and dentinal tubes.
Many
Calcospherites may be seen in connection with any of these.
irregular formations are found that are scarcely assignable to any of
these forms, and it is not unusual to find them intermixed with each
other.
Secondary Dentine is the result of a new growth excited by some
abnormal condition of, or injury to, the tooth. It is always deposited
upon the walls of the pulp-chamber, and results in the reduction of its
size. This must be distinguished from the normal growth of the dentine.
In the young the pulp-chamber is comparatively very large, and dimin-
ishes in size for some time (which cannot be definitely stated) after the
tooth has otherwise completed its growth or has attained the full form
of its root and crown. This growth is continuous with the general
structure of the dentine, without break or demarcation of any kind so
long as it continues normal ; but in case a new growth is excited by
abnormal conditions there is generally a departure from the normal
structure that distinguishes it sharply from the original dentine, and
enables us to make out the original form of the pulp-chamber. This
departure from the normal structure varies greatly in different cases.
It is occasionally marked by a sharp curve or change in the direction
of the tubules only, or there may be, and generally there is, a marked
diminution of their numbers. Occasionally the sudden diminishing of
the number of the tubules will be the only distinguishing mark, and in a
very few instances I have seen what seemed to be a great reduction in
the size of the chamber, tiiat had occurred with such perfect regularity
of structure as to leave no line of demarcation whatever ; but this is rare.
Generally there is a marked difference in the color of the new structure
Vol. I.—55
SECONDARY DENTINE. 865
perfectly satisfactory way at the present time ; and, besides, it does not
seem best to attempt to consider these entirely apart from the diseases
of the soft parts, for the reason that the one seems in many cases to be
directly dependent on the other. Some attempt at classification will,
however, serve the purpose of simplifying description ; I therefore give
the following
1st. Secondary Dentine.—A new growth of dentine more or less
regular in formation, excited by abrasion, decay, or other injury, by
which the dentinal fibrils are subjected to irritation at their distal ends.
2d, Dentinal Tumor within the Pulp-chamber.—An erratic growth of
dentine into the pulp-chamber united to the wall by a pedicle. The
structure is usually very irregular.
3d. Nodular Calcifications among, but not of, the Tissues of the Pulp.
—These are the irregular nodulated masses so frequently seen either as
very small stones or irregular masses. They contain many calcospher-
ites. These were considered with the soft parts for the sake of con-
venience.
4th. Interstitial Calcifications of the Tissues of the Pulp.—This is the
counterpart of calcifications elsewhere in the body, as in the arteries, etc.
5th. Cylindrical Calcifications of the Pulp, the tissues of Avhich are
probably in a state of fibrous degeneration. Usually seen in the pulp-
canals.
6th. Osteo-dentine.—Erratic formations showing; both the lacunse of
bone and dentinal tubes.
Many
Calcospherites may be seen in connection with any of these.
irregular formations are found that are scarcely assignable to any of
these forms, and it is not unusual to find them intermixed with each
other.
Secondary Dentine is the result of a new growth excited by some
abnormal condition of, or injury to, the tooth. It is always deposited
upon the walls of the pulp-chamber, and results in the reduction of its
size. This must be distinguished from the normal growth of the dentine.
In the young the pulp-chamber is comparatively very large, and dimin-
ishes in size for some time (which cannot be definitely stated) after the
tooth has otherwise completed its growth or has attained the full form
of its root and crown. This growth is continuous with the general
structure of the dentine, without break or demarcation of any kind so
long as it continues normal ; but in case a new growth is excited by
abnormal conditions there is generally a departure from the normal
structure that distinguishes it sharply from the original dentine, and
enables us to make out the original form of the pulp-chamber. This
departure from the normal structure varies greatly in different cases.
It is occasionally marked by a sharp curve or change in the direction
of the tubules only, or there may be, and generally there is, a marked
diminution of their numbers. Occasionally the sudden diminishing of
the number of the tubules will be the only distinguishing mark, and in a
very few instances I have seen what seemed to be a great reduction in
the size of the chamber, tiiat had occurred with such perfect regularity
of structure as to leave no line of demarcation whatever ; but this is rare.
Generally there is a marked difference in the color of the new structure
Vol. I.—55
