Abstract：
BACKGROUND: The Cusp of Carabelli (CoC) is the most commonly occurring dental morphological trait.
OBJECTIVE: To provide a pancontinental overview on the prevalence of the CoC in primary maxillary second molars and permanent maxillary molars.
METHODS: An electronic search was conducted on ten databases without year restrictions up to July 2020. All cross-sectional studies published in the English language reporting prevalence estimate of CoC were included. A modified version of the Newcastle-Ottawa scale was used to assess study quality. Meta-analyses were conducted for studies that reported data using Dahlberg and ASUDAS classification across continents.
RESULTS: For qualitative synthesis, 142 studies (45,327 participants) were included, of which 130 studies had moderate risk of bias. Random effects meta-analysis was performed for 41 studies. For prevalence of CoC in primary maxillary second molars, the estimate was 72% (2,829 participants). The overall percentage attained for permanent maxillary molars was 59% (16,607 participants) for first molars; 8% (2,277 participants) for second molars; and 10% (89 participants) for third molars. Subgroup analysis revealed the European continent reported the highest prevalence in permanent maxillary first and second molars.
CONCLUSIONS: Primary maxillary second molars recorded highest prevalence of CoC followed by permanent maxillary first, third and second molars. Pancontinental studies with regard to primary maxillary second molars are warranted.
OBJECTIVE: To provide a pancontinental overview on the prevalence of the CoC in primary maxillary second molars and permanent maxillary molars.
METHODS: An electronic search was conducted on ten databases without year restrictions up to July 2020. All cross-sectional studies published in the English language reporting prevalence estimate of CoC were included. A modified version of the Newcastle-Ottawa scale was used to assess study quality. Meta-analyses were conducted for studies that reported data using Dahlberg and ASUDAS classification across continents.
RESULTS: For qualitative synthesis, 142 studies (45,327 participants) were included, of which 130 studies had moderate risk of bias. Random effects meta-analysis was performed for 41 studies. For prevalence of CoC in primary maxillary second molars, the estimate was 72% (2,829 participants). The overall percentage attained for permanent maxillary molars was 59% (16,607 participants) for first molars; 8% (2,277 participants) for second molars; and 10% (89 participants) for third molars. Subgroup analysis revealed the European continent reported the highest prevalence in permanent maxillary first and second molars.
CONCLUSIONS: Primary maxillary second molars recorded highest prevalence of CoC followed by permanent maxillary first, third and second molars. Pancontinental studies with regard to primary maxillary second molars are warranted.
摘要：
背景：卡拉贝利尖顶（CoC）是最常见的牙齿形态特征。
目的：提供关于CoC在上颌第二磨牙和上颌永久磨牙中患病率的泛大陆概述。
方法：截至2020年7月，对10个数据库进行了电子搜索，没有年份限制。所有发表在英语语言报告中的CoC患病率估计的横断面研究都包括在内。纽卡斯尔-渥太华量表的修订版用于评估研究质量。对使用Dahlberg和ASUDAS分类报告数据的研究进行了荟萃分析。
结果：对于定性合成，纳入142项研究（45,327名参与者），其中130项研究存在中等偏倚风险.对41项研究进行随机效应荟萃分析。关于CoC在上颌第二磨牙中的患病率，估计为72%(2,829名参与者).第一磨牙的永久性上颌磨牙的总百分比为59％（16,607名参与者）；第二磨牙为8％（2,277名参与者）；第三磨牙为10％（89名参与者）。亚组分析显示，欧洲大陆报告的永久性上颌第一和第二磨牙患病率最高。
结论：上颌第二磨牙的CoC患病率最高，其次是永久性上颌第一磨牙，第三和第二磨牙。关于原发性上颌第二磨牙的泛大陆研究是有必要的。
目的：提供关于CoC在上颌第二磨牙和上颌永久磨牙中患病率的泛大陆概述。
方法：截至2020年7月，对10个数据库进行了电子搜索，没有年份限制。所有发表在英语语言报告中的CoC患病率估计的横断面研究都包括在内。纽卡斯尔-渥太华量表的修订版用于评估研究质量。对使用Dahlberg和ASUDAS分类报告数据的研究进行了荟萃分析。
结果：对于定性合成，纳入142项研究（45,327名参与者），其中130项研究存在中等偏倚风险.对41项研究进行随机效应荟萃分析。关于CoC在上颌第二磨牙中的患病率，估计为72%(2,829名参与者).第一磨牙的永久性上颌磨牙的总百分比为59％（16,607名参与者）；第二磨牙为8％（2,277名参与者）；第三磨牙为10％（89名参与者）。亚组分析显示，欧洲大陆报告的永久性上颌第一和第二磨牙患病率最高。
结论：上颌第二磨牙的CoC患病率最高，其次是永久性上颌第一磨牙，第三和第二磨牙。关于原发性上颌第二磨牙的泛大陆研究是有必要的。
