根管峡区的定位、发生率及临床意义

doi:10.12016/j.issn.2096-1456.2021.01.002

摘要/Abstract

摘要：

根管峡区（root canal isthmus,RCI）是位于同一牙根内、根管之间含有牙髓或牙髓衍生组织,呈现为带状狭窄的连接或含有交通支及横向吻合的解剖学结构,它常存在于含有两个根管的牙根中,解剖结构复杂。不同牙位的RCI发生率不尽相同,发生率最高的部位是下颌第一磨牙近中根和上颌第一磨牙近中颊根。RCI的存在增加了根管治疗的难度,并给患牙治疗带来了预后的不确定性。临床上,对于可能存在RCI的患牙建议使用锥形束CT及牙科显微镜进行识别;同时,对含RCI患牙治疗时应考虑选择合适的器械以及超声辅助下加强根管冲洗,有助于提高根管治疗以及根尖手术的成功率。目前的技术对于RCI的清理和充填仍存在一定的局限性,相应技术设备的研发改进是目前的研究热点,也是未来的研究方向。

关键词: 根管峡区, 根管解剖, 根管预备, 根管充填, 根管冲洗, 恒磨牙, 锥形束计算机断层扫描

Abstract:

Root canal isthmus(RCI) is defined as a narrow, ribbon-shaped communication between two root canals that contains pulp or tissue derived from pulp. Any root that contains two or more root canals has the potential to contain an isthmus. The incidence of RCI from different tooth positions varies, with the highest RCI incidences usually found in the mesial root of the mandibular first molar and the mesiobuccal root of the maxillary first molar. The presence of RCI increases the difficulty of root canal therapy and introduces uncertainty regarding the prognosis for dental treatment. It is recommended to use CBCT and dental microscopy to identify teeth with suspected RCI in clinical practice. At the same time, for treatment of teeth with RCI, appropriate instruments should be selected, and enhanced root canal irrigation assisted by ultrasound should be considered to improve the success rate of root canal treatment and endodontic root-end surgery. The current technology still has some limitations regarding the cleaning and filling of RCI and additional research and development. Improvement of the corresponding technology and equipment is a current research hotspot and a future research direction.

Key words: root canal isthmus, root canal anatomy, root canal preparation, root canal filling, root canal irrigation, permanent molar, cone-beam computed tomography

中图分类号:

孙书昱,王贺. 根管峡区的定位、发生率及临床意义[J]. 口腔疾病防治, 2021, 29(1): 11-19.

SUN Shuyu,WANG He. Location, incidence and clinical implications of the root canal isthmus[J]. Journal of Prevention and Treatment for Stomatological Diseases, 2021, 29(1): 11-19.

图/表 7

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Nationality	Sample number	Method	Prevalence （%）	Year of publication	Note
South Korea	31	Section observation	100	2020^[29]	The value was measured 3mm from the root tip
China	823	CBCT	64.6	2019^[9]	Mongoloid population
Brazil	140	Micro-CT	74.3	2019^[32]	The proportion of Type I-V was 52.9%,7.7%,2.9%,19.2% and 17.3% from the Hsu & Kim's classification
Iran	150	X-ray and Stereomicroscope	44.6	2017^[33]	The RCI prevalence of distal roots was 27.3%
USA	122	CBCT	64.7	2017^[24]	Mandibular second molars got a higher RCI prevalence without statistically difference
Brazil	132	CBCT	87.9	2015^[7]
India	150	Section observation	30	2012^[34]	The RCI prevalence of distal roots was 10
China	36	Micro-CT	49.5-66.1	2009^[35]	The value was observed 0-6 mm from the root tip, the highest RCI prevalence occurred in 4-6 mm from the root tip The RCI prevalence of distal roots was 17.3%-17.8%
UK	20	Micro-CT	17.25-50.25	2005^[36]	The value was observed 3-5 mm from the root tip, the highest RCI prevalence occurred in 3 mm from the root tip
Poland	50	Section observation	20	2004^[37]	The value was observed 3 mm from the root tip. The RCI prevalence of mandibular second molar was 18%
Brazil	50	Section observation	59	2003^[3]	The value was observed 0-6 mm from the root tip, the highest RCI prevalence occurred in 3-5 mm from the root tip

Nationality	Sample number	Method	Prevalence （%）	Year of publication	Note
South Korea	31	Section observation	100	2020^[29]	The value was measured 3mm from the root tip
China	823	CBCT	64.6	2019^[9]	Mongoloid population
Brazil	140	Micro-CT	74.3	2019^[32]	The proportion of Type I-V was 52.9%,7.7%,2.9%,19.2% and 17.3% from the Hsu & Kim's classification
Iran	150	X-ray and Stereomicroscope	44.6	2017^[33]	The RCI prevalence of distal roots was 27.3%
USA	122	CBCT	64.7	2017^[24]	Mandibular second molars got a higher RCI prevalence without statistically difference
Brazil	132	CBCT	87.9	2015^[7]
India	150	Section observation	30	2012^[34]	The RCI prevalence of distal roots was 10
China	36	Micro-CT	49.5-66.1	2009^[35]	The value was observed 0-6 mm from the root tip, the highest RCI prevalence occurred in 4-6 mm from the root tip The RCI prevalence of distal roots was 17.3%-17.8%
UK	20	Micro-CT	17.25-50.25	2005^[36]	The value was observed 3-5 mm from the root tip, the highest RCI prevalence occurred in 3 mm from the root tip
Poland	50	Section observation	20	2004^[37]	The value was observed 3 mm from the root tip. The RCI prevalence of mandibular second molar was 18%
Brazil	50	Section observation	59	2003^[3]	The value was observed 0-6 mm from the root tip, the highest RCI prevalence occurred in 3-5 mm from the root tip

Nationality	Sample number	Method	Prevalence （%）	Year of publication	Note
South Korea	28	Section observation	89.3	2020^[18]	The value was measured 3mm from the root tip
China	494	CBCT	92.5	2019^[30]	Investigated from a 9 to 12 years old population
Brazil	102	CBCT	60.8	2015^[7]
Brazil	50	Section observation	29	2003^[3]	The value was observed 0-6 mm from the root tip, the highest RCI prevalence occurred in 3-5 mm from the root tip
Canada	50	Section observation	62.5	2002^[31]
USA	50	Section observation	100	1995^[2]	The value was observed 0-6 mm from the root tip, the highest RCI prevalence occurred in 4 mm from the root tip

Nationality	Sample number	Method	Prevalence （%）	Year of publication	Note
South Korea	28	Section observation	89.3	2020^[18]	The value was measured 3mm from the root tip
China	494	CBCT	92.5	2019^[30]	Investigated from a 9 to 12 years old population
Brazil	102	CBCT	60.8	2015^[7]
Brazil	50	Section observation	29	2003^[3]	The value was observed 0-6 mm from the root tip, the highest RCI prevalence occurred in 3-5 mm from the root tip
Canada	50	Section observation	62.5	2002^[31]
USA	50	Section observation	100	1995^[2]	The value was observed 0-6 mm from the root tip, the highest RCI prevalence occurred in 4 mm from the root tip