Skinner Mark F, Newell Elizabeth A
Department of Archaeology, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada.
Am J Phys Anthropol. 2003 Jan;120(1):61-72. doi: 10.1002/ajpa.10149.
This paper extends observations by Lukacs ([1999] Am. J. Phys. Anthropol. 110:351-363; [2001] Am. J. Phys. Anthropol. 116:199-208) of localized hypoplasia of the primary canine (LHPC) among large apes to gibbons, bonobos, and orangutans. LHPC is a roughly circular area of deficient enamel on the labial surface of primary canine teeth which, on current evidence from humans, forms several months after birth due to malnutrition-induced craniofacial osteopenia, leading to crypt fenestration that exposes the dental follicle and more deep-sited ameloblasts to minor physical traumata during normal motor infant development. Our goal was to determine the prevalence of LHPC among a variety of apes which differ in body mass and socioecology, with a view to elucidating the etiology of the defect. We examined juvenile dentitions from 122 animals from three taxa: 8 Hylobates lar, 75 Pongo pygmaeus from Borneo and Sumatra, and 39 Pan paniscus from central Africa. Reported variables include taxon, sex, arcade, side, and tooth size. Presence/absence and ordinal severity of defect expression were recorded by description, microphotography, and scanning electron microscopy. Molds were taken in high-resolution dental impression materials and cast in epoxy resin. There are clear taxonomic, but no sex, differences. Prevalence ranged from 0.0% in gibbons to 61.5% in bonobos and 85.3% in orangutans. The result for orangutans is similar to that reported by Lukacs ([1999] Am. J. Phys. Anthropol. 110:351-363), while bonobos are much more affected than were the common chimpanzees (22%) described by Lukacs ([1999] Am. J. Phys. Anthropol. 110:351-363). There are no significant antimeric differences, but the lower canine is much more affected than the upper by LHPC. We show that larger teeth are more affected by LHPC and have more severe defects. Also, we encountered several instances of patent or healing canine crypt fenestrations, occasionally in direct association with LHPC. Location of the defect indicates that LHPC may occur perinatally but more usually several months postnatally. Histological examination showing the neonatal line and LHPC is required to resolve the issue of timing. We concur with Lukacs ([1999] Am. J. Phys. Anthropol. 110:351-363) that taxonomic, anatomical, and environmental variables combine to determine the occurrence and appearance of LHPC. Nevertheless, we conclude that LHPC probably reflects deficient growth of the arcades in infant apes and humans.
本文将卢卡奇（[1999]《美国体质人类学杂志》110:351 - 363；[2001]《美国体质人类学杂志》116:199 - 208）对大型猿类中乳犬齿局部发育不全（LHPC）的观察扩展至长臂猿、倭黑猩猩和猩猩。LHPC是乳犬齿唇面釉质缺损的大致圆形区域，根据目前来自人类的证据，它在出生后数月形成，是由于营养不良导致的颅面骨质减少，进而导致隐窝开窗，使牙囊和更深层的成釉细胞在婴儿正常运动发育过程中受到轻微物理创伤。我们的目标是确定LHPC在体重和社会生态学不同的各种猿类中的患病率，以阐明该缺陷的病因。我们检查了来自三个分类群的122只动物的幼年齿列：8只白掌长臂猿、75只来自婆罗洲和苏门答腊的婆罗洲猩猩以及39只来自中非的倭黑猩猩。报告的变量包括分类群、性别、牙弓、侧别和牙齿大小。通过描述、显微摄影和扫描电子显微镜记录缺陷表达的有无及序数严重程度。用高分辨率牙科印模材料取模并浇铸在环氧树脂中。存在明显的分类学差异，但无性别差异。患病率从长臂猿的0.0%到倭黑猩猩的61.5%以及猩猩的85.3%不等。猩猩的结果与卢卡奇（[1999]《美国体质人类学杂志》110:351 - 363）报告的相似，而倭黑猩猩受影响的程度比卢卡奇（[1999]《美国体质人类学杂志》110:351 - 363）描述的普通黑猩猩（22%）要高得多。没有明显的左右差异，但LHPC对下犬齿的影响比对上犬齿大得多。我们发现较大的牙齿受LHPC影响更大且缺陷更严重。此外，我们遇到了几例开放性或愈合性犬齿隐窝开窗的情况，偶尔与LHPC直接相关。缺陷的位置表明LHPC可能在围产期出现，但更常见于出生后数月。需要进行显示新生儿线和LHPC的组织学检查来解决时间问题。我们赞同卢卡奇（[1999]《美国体质人类学杂志》110:351 - 363）的观点，即分类学、解剖学和环境变量共同决定了LHPC的发生和表现。然而，我们得出结论，LHPC可能反映了猿类和人类婴儿牙弓生长不足。
