were located in the neck and/or root of the approximal surface (NRAS). Caries ... modern population, the most frequent lesion is on the approximal surface (AS), ...
Jpn. J. Oral Biol., 44: 87-95, 2002.
ORIGINAL
Historical
Change
Prehistoric
of Dental to Modern
Carious
Lesions from
Times in Japan
Hisashi Fujita Departmentof Anthropology, TheNiigataPrefecturalMuseumof History Sekihara-cho, Nagaoka940-2035,Japan (Receivedon August1, 2001;Acceptedon November19,2001) Keywords: lesionof caries/historicalchange/dentalattrition/rootcaries/Japanese Abstract:
The aim of this study was to document
the historical
change
Japanese people. The majority of carious lesions in historical populations were located in the neck and/or root of the approximal surface (NRAS).
of dental
caries
lesions in the
from the Jomon to Edo period Caries on the occlusal surface
(OS) were rare in both the Jomon and Kofun populations, but there was a relatively high rate (17.6-24.7%) in the Kamakura, Muromachi and Edo periods. People in both the Jomon and Kofun periods had severe dental attrition; therefore, due to the disappearance of fissures and pits, caries on the OS did not arise. However, after the Kamakura period, the attrition was moderate, so occlusal caries increased. Caries on the lingual surface (LS) and the neck and/or root of the lingual surface (NRLS) were rare in all Japanese periods. The incidence may be associated with a self-cleaning action with the tongue and the saliva. In the modern population, the most frequent lesion is on the approximal surface (AS), followed by the NRAS and the OS. The rate of coronal
caries is higher than that of root caries only in modern times. It seems reasonable
to suppose that the former is a modern type of caries, and the latter is ancient. Furthermore, it can be said that from the Jomon to Kofun or from the Kofun to Kamakura periods, and from the Edo to modern times, are turning points for different types of caries in the history of Japan. The type of carious lesion is a good indicator of oral health condition, including dietary habits, subsistence and lifestyle in each period.
抄 録:本
研 究 の 目 的 は,日 本 人 集 団 に お け る齲 蝕 発 症 部 位 の歴 史 的 変 遷 を 明 ら か に す る こ とで あ る 。
縄 文 時 代 か ら江 戸 時 代 まで の 日本 人 の 齲 蝕 発 症 部 位 で 最 も頻 度 の 高 い の は,隣 接 面 歯 頸 根 部(NRAS)で 縄 文 時 代 と古 墳 時 代 に は,咬 合 面 齲 蝕(OS)が
少 な い が,鎌 倉 時 代 以 降 江 戸 時 代 まで,OSは
あ る。
か な り高 い頻 度 を
示 す 。 これ は縄 文 時 代 人 と古 墳 時 代 人 は 歯 の 咬 耗 が 著 し い た め,小 窩 裂 溝 が 消 滅 す る こ と に よ っ て,咬 合 面 に は 齲 蝕 が 生 じ に くか っ た と考 え ら れ る。反 対 に,鎌 倉 時 代 以 降 は咬 耗 の 程 度 が 軽 度 化 す る こ と に よ ってOSが た と思 わ れ る。 舌 側 面(LS)お これ は,舌
よ び舌 側 面 歯 頸 根 部(NRLS)の
や 唾 液 が 歯 面 を 清 掃 す る い わ ゆ る 自浄 効 果 の た め で あ ろ う。 現 代 人 に お い て は,隣
最 も多 く,次 い でNRASとOSで した が っ て,根
接 面 齲 蝕(AS)が
あ る。歯 冠 部 齲 蝕 の 頻 度 が 根 面 齲 蝕 の そ れ を上 回 る の は,現 代 人 だ け で あ る 。
面 齲 蝕 は古 代 型 齲 蝕,歯
歴 史 に お い て は,縄
増加 し
齲 蝕 は,全 時 代 を通 じ て 日本 人 に は 少 な か っ た 。
冠 部 齲 蝕 は 現 代 型 齲 蝕 とみ な す こ とが で き そ う で あ る 。 さ ら に,日 本 の
文 時 代 か ら古 墳 時 代,古
墳 時 代 か ら鎌 倉 時 代 と,江 戸 時 代 か ら現 代 へ い た る各 時 期 が,齲
発 症 部 位 の タ ー ニ ン グ ポ イ ン トで あ っ た と い え る。 齲 蝕 の 発 症 部 位 は そ れ ぞ れ の時 代 の食 生 活,生 イ フ ス タ イ ル を含 め た 口 腔 衛 生 を探 る う えで の 良 き指 標 で あ る と思 わ れ る。
業,そ
蝕
して ラ
88
Jpn. I. Oral Biol., 44: 87-95, 2002.
Edo periods) Introduction The outbreak closely associated
of caries
skeletal
cavities
is believed
to be
with oral health, including dietary
were derived
remains
from
from many
excavated
human
sites in Japan,
and the
teeth from the modern population
had been extracted.
The
derived
excavated
materials
were
from
five
habits, and the age of the individuals.
population groups, defined by archaeological/historical features: Jomon period (ca. 10000-300 BC),
study of carious
Kofun period
understanding and custom
Therefore , the lesions is thought to offer a key to
the dietary habits, subsistence, life span
only the modern
lifestyle , in not but also the ancient populations .
Previous
have
ancient
and/or
the
examined
modern
caries
populations
lesions
number
in
of individuals
materials
in various
Particularly,
Museum, Tokyo.
not been examined
Japan. In this study, dental caries were investigated the Jomon
the Department
in
of Anthropology,
National
dietary
times, and to estimate
period
the oral health
to
et
of these materials
is
shown in Table 2. However, the extraction age and other information
and
habits, including lifestyle, in each period .
are unknown.
Dental caries were diagnosed well-lit
conditions.
Caries
were
popula-
by Ninomiya,
rials are housed in the Kyushu Oral Health
from the Jomon
Science
and 1287 mandibular
teeth, which were reported
in dental
lesion
and Pre-
The teeth from the modern
distribution
dates, sex, These mateInstitute.
using an explorer defined
and Methods
two groups;
used in this study were divided into
the historical
teeth
(from the Jomon to Table
of the
tooth equal to or greater than Grade 1 (C1) in clinical inspection.
The materials
in
as clearly
necrotic decay in enamel, dentine or cementum Materials
are
of Tokyo and
al.12). The tooth-type
caries
to the present
carious
excavated
of Anthropology
Museum, University
tion consisted of 1308 maxillary from
these
in Japan , and classified according to the location of the lesion . The aim of this study was to examine the historical change modern
population
regarding
housed in the Department history, University
has
period
are shown in Table 1. These materials
parts of the world1-16), however, there are not many studies on the historical change of caries lesions17-19). this area
AD), Kamakura
(1192-1333 AD), Muromachi period (1336-1573 AD), and Edo period (1603-1868 AD). The site names and
of oral health, including
studies
(ca. 300-700
1
Excavated
Caries
lesions were classified
groups3): occlusal surface (OS), approximal (AS), neck and/or root of approximal
materials
used
in this
study
into eight surface surface
H. Fujita:
(NRAS), buccal surface buccal surface (NRBS), and/or
(NRLS)
destruction
as follows:
of the tooth had
proceeded so far that it was impossible to determine the site of the initial lesion. Sex and age in all of the materials were pooled. The number of historical materials from the Jomon to Edo period
is not enough
to discuss
cavities and frequencies by tooth-type, mary overview is presented. The significance examined
of differences
89
Results
and unjudgea-
(U) was considered
in a few cases, carious
Change of Caries Lesion in Japanese
(BS), neck and/or root of lingual surface (LS) , neck
root of lingual surface
ble (U). Unjudgeable
Historical
the caries
so only a sum-
1. Caries cavities through time Tables 3-1 to 3-6 show the total number of caries cavities and the percentages
of the different
carious cavities observed in each population. The total number of cavities was slightly larger than the total
number
of carious
teeth since a single tooth
could have more than one carious lesion. Tables 3-1 to 3-6 were simplified in Fig. 1. In the Jomon period, the most frequent
between values was
by x2 test, and p-values
