Hajime Hanamura

Biographic Data

ID135257
NAMEHajime Hanamura
GIVEN NAMESHajime
FAMILY NAMEHanamura
SIGNATUREHANAMURA H
AFFILIATIONSAichi Gakuin University
VERIFIEDNo
TOTAL WORKS15
TOTAL CITATIONS3
AUTHOR COUNT15
EDITOR COUNT0
FIRST PUBLICATION YEAR1965
LATEST PUBLICATION YEAR2010
H-INDEX1

  • Analysis of Heredity Factors in the Morphological Variation of the Maxillary Lateral Incisor by a Twin Model

    Open AccessShintaro Kondo, Masanobu Matusno et al.ARTICLEAnthropological Science2010References: 19

    歯の形態に関与する遺伝・環境要因の分析は双生児法による研究が多数報告されてきた。この方法は遺伝子を100%共有する一卵性双生児(MZ)と約50%共有する二卵性双生児(DZ)とを環境変化のもとで比較することで遺伝性を検討する。肉眼的観察により上顎側切歯退化を大きさと形に分けて評価した。退化した場合を(+),退化がない場合を(−)として,左・右側および双生児ペア内で比較を行い,両方が退化した場合(++)の一致率を検討した。双生児ペア間の一致率はMZの方がDZより高かったが,MZの一致率は50~60%であったことから環境要因が強く関係している。また,大きさの方が形より一致率が高く,遺伝性が高いと考えられる。最近の研究から一卵性双生児における形質の不一致は胎生期の栄養供給の不均衡による成長の違いやエピジェネシスの可能性が指摘されている。本研究で環境要因の影響と推測した中にはこうした要因も含まれている可能性がある

  • Tooth size in individuals with congenitally missing teeth: A study of Japanese males

    Open AccessHiroyuki Yamada, Shintaro Kondo et al.ARTICLEAnthropological Science2010Cited by: 1References: 1

    There is evidence of a relationship between tooth size and tooth agenesis in human populations, with a tendency for reduced tooth size in individuals with missing teeth. The aim of this study was to analyze the size of remaining teeth (mesiodistal crown diameters) and their variability in individuals with varying degrees of severity of congenitally missing teeth. Tooth crown diameters were recorded from 100 dental plaster casts of Japanese males.…

  • Tooth Size and Molar Crown Characters of Individuals with Third Molar Agenesis in Japanese

    Open AccessHiroyuki Yamada, Shintaro Kondo et al.ARTICLEAnthropological Science2005Cited by: 1References: 16

    第3大臼歯の先天性欠如にともなって他歯の大きさ・形態がどのように変化するかを調査した。対象は日本人成人男性169名である。第3大臼歯の欠如様式により歯の大きさは4歯存在群,片側欠如群,両側欠如群,4歯欠如群の4群に,形態は4歯存在群,片側・両側欠如群,4歯欠如群の3群に分けて上・下顎を別々に分析した。 歯冠近遠心径では第3大臼歯が欠如した3群は4歯存在群よりもほとんどの歯で大きな値を示していた。とくに4歯欠如群は4歯存在群よりも上・下顎第1・第2大臼歯が有意に大きかった。すなわち,第3大臼歯が4歯とも欠如すると,上・下顎の第1・第2大臼歯の近遠心径はとくに強く影響を受け,大臼歯列長を代償していると考えられる。 第3大臼歯欠如による残りの歯の変動は4歯存在群よりも欠如群で,下顎歯よりも上顎歯で一般的に高くなる傾向があるが,歯種や欠如歯数においては必ずしも欠如群がすべて高くなるとは限らなかった。 歯冠形態では咬頭数および溝型とも上・下顎第1大臼歯は欠如した群と4歯存在群の間に有意な頻度の違い…

  • Secular Change of Third Molar Agenesis in the Japanese Population

    Open AccessHiroyuki Yamada, Shintaro Kondo et al.ARTICLEAnthropological Science2004References: 32

    人の第3大臼歯は最も発生が遅く,形態変異も大きく,欠如率も高い。環境要因の影響を最も受けやすく,小進化を反映しやすい歯である。そこで,日本人集団の歯牙形態の小進化を考察する目的で,第3大臼歯の先天的欠如率を時代順に調べた。その結果,縄文時代人は欠如頻度が低く,ほとんどの第3大臼歯は発生していたが,弥生時代人になると急激に欠如頻度が高くなっていた。この急激な変化は,外来集団からの遺伝的影響によって生じたと考えられる。弥生時代人以降,欠如頻度はさらに高くなり,昭和初期にはピークに達した。その後,先天的欠如頻度は急激に減少し,第3大臼歯が存在する人は多くなっていた。昭和時代以降の変化は高栄養物の摂取と,それに伴う高身長化や性成熟の加速化によるものと思われる

  • Distribution of Tabercle-shaped Incisors in South Pacific Populations

    Open AccessEisaku Kanazawa, Yuji Shirono et al.ARTICLEAnthropological Science2001Cited by: 1References: 2

    The basal tubercle and its related traits on the basal part of the lingual surface of maxillary central incisors vary in developmental grades. Although a well-developed basal tubercle was observed in fossil humans, much attention to this trait has not been paid in modern humans. We compared five morphological traits on the lingual surface of maxillary incisors among seven Pacific populations. Results showed that the South-Pacific populations exam…

  • Tubercle-shaped Incisor of the Cook Islanders

    Open AccessHiroyuki Yamada, Hajime Hanamura et al.ARTICLEAnthropological Science2000

    A well-developed basal tubercle was found in the lingual surface of the upper central incisor in the Cook Islanders. The basal tubercle was accompanied with large spines, and limited to the central incisor. Such a configuration was thought to be almost the same characteristic as the “tubercle-shaped” incisor observed in Homo erectus, Peking man in China (Adloff, 1938). Females exceeded males in frequency of the basal tubercle. This characteristic…

  • Occlusion and Inclination of the Pashtun and Tajik in Afghanistan

    Open AccessTakuro Sakai, Hajime Hanamura et al.ARTICLEThe Journal of Anthropological…1973

    We have reported previously on the descriptive features and the size of the dentition of the Pashtun and Tajik in Afghanistan. The present work concerns an occlusion and incisor inclination. The materials used were 111 upper and lower plaster casts of 74 Pashtuns and 37 Tajiks. The materials of the Japanese used in comparative study were 184 upper and lower plaster casts. On these plaster casts vertical overbite, horizontal overbite (overjet) (fi…

  • A Morphological Study of Enamel-Dentin Border on the Japanese Dentition: VII. General Conclusion

    Open AccessTakuro Sakai, Hajime HanamuraARTICLEThe Journal of Anthropological…1973

    The authors dercribed the crown characters of the Japanese permanent dentition on the exterior surface of enamel and on the interior surface of dentinoenamel border in previous chapters. The present article gives general conclusion as the last chapter of this work. The junction of the enamel and dentin has been investigated in several ways in the past. We used acid to dissolve away the enamel for our studies of the dentin core, and interpreted ma…

  • A Morphological Study of Enamel-Dentin Border on the Japanese Dentition: VI. Mandibular Molar

    Open AccessTakuro Sakai, Hajime HanamuraARTICLEThe Journal of Anthropological…1973

    We have reported on the pattern of the enamel-dentin border of the incisors, canines, premolars and maxillary molars in this journal (vol. 73, no. 3, vol. 75, no. 4, 5, vol. 77, no. 3, vol. 79, no. 4). The present article is the description on the mandibular molars as the sixth chapter of our work. The materials used in this study were 114 mandibular first molars and 77 second molars.The results were summarized as follows:1. On the enamel-dentin …

  • Tooth Size of the Pashtun and Tajik in Afghanistan

    Open AccessTakuro Sakai, Hajime Hanamura et al.ARTICLEThe Journal of Anthropological…1971

    We have reported previously on the descriptive features of the dentition of the Pashtun and Tajik in Afghanistan. The present work concerns an odontometric investigation on the Pashtun and Tajik. The materials used were 114 upper and lower plaster casts of 75 Pashtuns and 39 Tajiks. The materials of the Japanese used in comparative study were 91 upper and lower plaster casts. On these plaster casts mesiodistal and buccolingual crown diameters wer…

  • A Morphological Study of Enamel-Dentin Border on the Japanese Dentition: V. Maxillary Molar

    Open AccessTakuro Sakai, Hajime HanamuraARTICLEThe Journal of Anthropological…1971

    We have reported previously on the pattern of the enamel-dentin border of maxillary median incisor, maxillary canine, maxillary premolar and mandibular premolar in this journal (Vol. 73, no. 3, Vol. 75, no, 4, 5, Vol. 77, no. 3). The present article is the description on maxillary molar as the fifth chapter of our work. The material used in this study were 125 maxillary first molars and 100 second molars

  • AMorphological Study of Enamel-Dentin Border On the Japanese Dentition IV.Mandibular Premolar

    Open AccessTakuro Sakai, Izumi SASAKI et al.ARTICLEThe Journal of Anthropological…1969

  • A Morphological Study of Enamel-Dentin Border on the Japanese Dentition: III. Maxillary Premolar

    Open AccessTakuro Sakai, Izumi SASAKI et al.ARTICLEThe Journal of Anthropological…1967

    We have reported previously on the morphology of the enamel-dentin border of maxillary median incisor and canines in this journal (Vol. 73, No. 3 and Vol. 75, No. 4). The present article is the description on maxillary premolar as the third chapter of our work. The materials used in this study were 125 extracted maxillary first premolars and 54 second premolars

  • A Morphological Study of Enamel-Dentin Border on the Japanese Dentition: II. Maxillary Canine

    Open AccessTakuro Sakai, Izumi SASAKI et al.ARTICLEThe Journal of Anthropological…1967

    We have reported previously on the morphology of the enamel-dentin border of maxillary median incisor in this journal (Vol. 73, No. 3, 1965). The present article is the description on maxillary canine as the second chapter of our work

  • A Morphological Study of Enamel-Dentin Border on the Japanese Dentition

    Open AccessTakuro Sakai, Izumi SASAKI et al.ARTICLEThe Journal of Anthropological…1965

    The exterior surface of the enamel layer of the teeth has frequently beensubject of morphological, morphogenetic and anthropological considerations. But regarding the interior surface of the enamel cap (enamel-dentin border), a few studies have been reported. To ascertain the morphological relationships between enamel surface and enamel-dentin border of the maxillary median incisor, the enamel has been artificially removed by means of acids