Morphological variations of the labial frenum, type of attachment and presence of diastemas: integrative review

SANTOS, Aline; SILVA, Lindinalva Marielly; LIMA, Isabela; OLIVEIRA, Lívia Maria Lopes de; VAJGEL, Bruna de Carvalho Farias; CIMÕES, Renata

doi:10.1590/1981-86372023001220210122

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RGO - Revista Gaúcha de Odontologia

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ORIGINAL • Rev Gaúch. Odontol. 71 • 2023 • https://doi.org/10.1590/1981-86372023001220210122 copy

Morphological variations of the labial frenum, type of attachment and presence of diastemas: integrative review

Variações morfológicas do freio labial, tipo de inserção e presença de diastemas: revisão integrativa

Authorship SCIMAGO INSTITUTIONS RANKINGS

ABSTRACT

Objective:

The aim of the present literature review was to compile data on the frequency of morphological and attachment types of the upper and lower labial frenum in different populations and investigate the association between the attachment level of the upper labial frenum and the occurrence of diastemas.

Methods:

Searches were conducted between May and June 2021 in the Medline (via Ovid), Google Scholar and CAPES databases. Thirty-eight studies that evaluated frenum morphology, frenum morphology and attachment or frenum morphology, attachment and the occurrence of diastemas were selected for the extraction of data.

Results:

Based on the data compiled in this review, the most common morphological and attachment types were labial frenum normale and mucosal attachment. The papillary and papilla penetrating types of attachment were more associated with the occurrence of diastemas.

Conclusion:

Longitudinal studies are needed to investigate this correlation in children and adults.

Indexing terms
Anatomy; Diastema; Labial frenum

Study	Country	Sample size	Age (years)	Location of frenum	Morphological Type of Upper Labial Frenum (%)
					Diastemas (%)
					A	B	C	D	E	F	G	H
Sewerin (1971) [⁹9 Sewerin IB. Prevalence of variations and anomalies of the upper labial frenum. Acta Odontol Scand. 1971; 29(4):487-496. https://doi.org/10.3109/00016357109026535 https://doi.org/10.3109/0001635710902653... ]	Denmark	1430	0-60	UL	60.2	19.9	9.1	3	2.8	2.6	2.1	0.4
	Denmark	1430	0-60	UL	-	-	-	-	-	-	-	-
Ruli et al. (1997) [¹¹11 Ruli LP, Duarte CA, Milanezi LA, Perri SHV. Frênulo labial superior e inferior: estudo clínico quanto a morfologia e local de inserção e sua influência na higiene bucal. Rev Odontol Univ São Paulo. 1997;11(3). https://doi.org/10.1590/S0103-06631997000300008 https://doi.org/10.1590/S0103-0663199700... ]	Brazil	100	19-26	UL and LL	69	10	15	1	3	1	0	1
	Brazil	100	19-26	UL and LL	-	-	-	-	-	-	-	-
Braga et al. (2006) [¹²12 Braga AT, Quelemes PV, Moura WL, Moura WL. Descrição da morfologia dos frênulos labiais superiores em escolares de Teresina. Rev Cir Traumatol Buco-Maxilo-facial. 2006;7(3):59-64.]	Brazil	300	7-10	UL	57.3	3.6	11.3	2.3	3.6	15	0.6	6
	Brazil	300	7-10	UL	-	-	-	-	-	-	-	-
Díaz-Pizán et al (2006) [¹⁸18 Díaz-Pizán ME, Lagravère O, Villena R. Midline diastema and frenum morphology in the primary dentition. J Dentr Child. 2006;73(1):11-14.]	Peru	1355	0-6	UL	59	42	12	<1	<1	25	<1	<1
	Peru	1355	0-6	UL	-	-	-	-	-	-	-	-
Kakodkar et al. (2008) [³⁹39 Kakodkar P, Patel T, Patel S, Patel S. Clinical assessment of diverse frenum morphology in permanent dentition. J Dental Sci. 2008;7(2):1-8.]	India	1206	12-17	UL	70.6	3.9	17.6	<1	<1	6.6	<1	0
	India	1206	12-17	UL	-	-	-	-	-	-	-	-
Gusmão et al. (2009) [¹³13 Gusmão ES, Souza PFJC, Vasconcelos RB, Claus RP, Cimões R, Coelho RS. Inserção e morfologia dos freios labiais. Odontol Clínico Científ. 2009; 8(2):133-139.]	Brazil	261	18- 72	UL and LL	79.7	11.1	7.7	0.4	0	0	0	1.1
	Brazil	261	18- 72	UL and LL	-	-	-	-	-	-	-	-
Townsend et al. (2012) [⁴²42 Townsend JA, Brannon RB, Cheramie T, Hagan J. Prevalence and variations of the median maxillary labial frenum in children, adolescents, and adults in a diverse population. Gen Dent. 2013;61(2):57-60;]	USA	284	3-74	UL	69.3	10.5	17.6	0.7	0.3	1.4	1	0
	USA	284	3-74	UL	-	-	-	-	-	-	-	-
Estrada (2014) [²⁰20 Estrada SNT. Incidencia de Variantes Anatómicas del Frenillo Labial Superior en los y las estudiantes de 1 8 a 3 0 años de edadd e la universidad nacional de loja modal dadde estudios presencial en el periodo mayo – julio de 2014. Loja, Ecuador: Universidad Nacional de Loja Área de La Salud Humana Carrera de Odontología; 2014.]	Ecuador	894	18-30	UL	74.8	19.7	4.3	0.2	0	0.5	0.2	0
	Ecuador	894	18-30	UL	-	-	-	-	-	-	-	-
Christabel & Gurunathan (2015) [²¹21 Christabel SL, Gurunathan D. Prevalence of type of frenal attachment and morphology of frenum in children, Chennai, Tamil Nadu. World J Dent. 2015;6(4):203-207. https://doi.org/10.4103/jisp.jisp_294_17:10.4103/jisp.jisp_294_17. https://doi.org/10.4103/jisp.jisp_294_17... ]	India	931	3-12	UL	97	0	2.6	0.4	0	0	0	0
	India	931	3-12	UL	-	-	-	-	-	-	-	-
Jindal et al. (2016) [²²22 Jindal V, Kaur R, Goel A, Mahajan A, Mahajan N, Mahajan A. Variations in the frenal morphology in the diverse population: a clinical study. J Indian Soc Periodont. 2016;20(3):320-323. https://doi.org/10.4103/0972-124X.182598 https://doi.org/10.4103/0972-124X.182598... ]	India	500	16-40	UL	77.6	9	12.41	0	0	0	0	0
	India	500	16-40	UL	-	-	-	-	-	-	-	-
Ribeiro et al. (2015) [¹⁴14 Ribeiro ILA, Fernandes TL, Trigueiro DA, Souza CFM, Medeiros JMD. Avaliação dos padrões de morfologia e inserção dos freios labiais em pacientes da clínica-escola de odontologia do Centro Universitário de João Pessoa - PB. Rev Odontol UNESP. 2015;44(5):268-272. https://doi.org/10.1590/1807-2577.1081 https://doi.org/10.1590/1807-2577.1081... ]	Brazil	385	10-72	UL and LL	82.6	4.5	10.4	0.7	0	0.5	1.3	0
	Brazil	385	10-72	UL and LL	-	-	-	-	-	-	-	-
Bervian et al. (2016) [¹⁵15 Bervian J, Cazarotto F, Perussolo B, Patussi EG, Pavinatto LCB. Description of the Upper Labial Frenulum Characteristics in Preschool Children of Passo Fundo, Brazil. Braz Res Pediatric Dent Integr Clinic. 2016;16(1):351-357. http://dx.doi.org/10.4034/PBOCI.2016.161.37 https://doi.org/10.4034/PBOCI.2016.161.3... ]	Brazil	304	0-6	UL	77.3	8.6	2.63	0.32	0	8.6	2.6	0
	Brazil	304	0-6	UL	-	-	-	-	-	-	-	-
Sagar et al. (2016) [²³23 Sagar S, Heraldsherlin J, Moses S. Morphological variation of abnormal maxillary labial frenum in South Indian population. Int J Pharmaceutical Sci Res. 2016;7(5):2142-2146. http://dx.doi.org/10.13040/IJPSR.0975-8232. https://doi.org/10.13040/IJPSR.0975-8232... ]	India	60	15-25	UL	0	16.6	28.3	13.3	1.67	20	0	20
	India	60	15-25	UL	-	40	52.9	50	0	75	0	66.6
Dasgupta et al. (2017) [²⁴24 Dasgupta P, Kamath G, HS S, Babshet M, Doddamani L. Morphological variations of median maxillary labial frenum: a clinical study. J Stomatol Oral Maxillofac Surg. 2017;118(6):337-34. https://doi.org/10.1016/j.jormas.2017.06.018 https://doi.org/10.1016/j.jormas.2017.06... ]	India	1400	5-74	UL	67.78	11.9	16.5	0	0.8	1.7	0.07	1
	India	1400	5-74	UL	-	-	-	-	-	-	-	-
Hammouri et al. (2017) [⁴⁰40 Hammouri E, Ghozlan M, Alsmadi H, Rihani F, Alrawashdeh T. Morphology and positional characteristics of maxillary labial frenum in Jordanian children. J Royal Med Serv. 2017;24(2):35-40. https://doi.org/10.1016/j.jormas.2017.06.018 https://doi.org/10.1016/j.jormas.2017.06... ]	Jordan	300	1-13	UL	54.6	9.6	25.6	2	0	4.3	0.3	3.33
	Jordan	300	1-13	UL	-	-	-	-	-	-	-	-
Niazi et al. (2017) [²⁵25 Niazi M, Manzoor N, Sajjad S, Qazi HS. Morphological and attachment variations of median maxillary labial frenum. J Pakistan Orthop. 2017;9(1):19-23.]	Pakistan	600	5-63	UL	54.3	6.3	3.1	0.1	1	34.6	0.1	0.1
	Pakistan	600	5-63	UL	-	-	-	-	-	-	-	-
Thosar et al. (2017) [³⁸38 Thosar N, Murarka P, Baliga S, Rathi N. Assessment of maxillary labial frenum morphology in primary mixed, and permanent dentitions in Wardha district. Eur J General Dent. 2017;6:14-17. https://doi.org/10.4103/2278-9626.198601 https://doi.org/10.4103/2278-9626.198601... ]	India	1000	3-14	UL	88.3	0.6	4.7	0.7	0.1	2.1	0.6	0.7
					-
						-	-	-	-	-	-	-
Jonathan et al. (2018) [⁸8 Jonathan PT, Himani T, Abhiruchi G, Virat G, Neha G. Maxillary labial frenum morphology and midline diastema among 3 to 12-year-old schoolgoing children in Sri Ganganagar city: a cross-sectional study. J Indian Soc Pedod Prev Dent. 2018; 36(3):234-239. https://doi.org/10.4103/JISPPD.JISPPD_51_18. https://doi.org/10.4103/JISPPD.JISPPD_51... ]	India	1200	3-12	UL	68.7	5	10.3	0	0	15.3	0.3	0.16
	India	1200	3-12	UL	31.1	1.1	1.1	0	0	66.6	0	0
Manjunath (2018) [²⁶26 Manjunath N, George AM, Mathew NML. The frenum and the diastema: a clinical observational study. Int J Innov Sci Res Technol. 2018;3(9):560-563.]	India	100	18-50	UL	65	19	8	4	1	0	2	0
	India	100	18-50	UL	-	10.5	12.5	50	100	0	0	0
Pandiyan et al. (2018) [²⁷27 Pandiyan NJ, Hedge A. Clinical assessment of frenum morphology and attachment in malaysian children. Pesq Bras Odontoped Clinica Integr. 2018;18(1):1-9. http://dx.doi.org/10.4034/PBOCI.2018.181.20 https://doi.org/10.4034/PBOCI.2018.181.2... ]	Malaysia	200	2-15	UL	73	5	11.5	7.5	0	2.5	0	0.5
	Malaysia	200	2-15	UL	-	-	-	-	-	-	-	-
Rajani et al. (2018) [²⁸28 Rajani ER, Biswas PP, Emmatty R. Prevalence of variations in morphology and attachment of maxillary labial frenum in various skeletal patterns – A cross-sectional study. J Indian Soc Periodontol. 2018;22(3):257-262. https://doi.org/10.4103/jisp.jisp_294_17. https://doi.org/10.4103/jisp.jisp_294_17... ]	India	150	13-30	UL	45.33	6	12	19.3	2.6	1.3	1.3	4
	India	150	13-30	UL	-	-	-	-	-	-	-	-
Bowsiyaand & Arjunkumar (2019) [⁴¹41 Bowsiya S, Arjunkumar R. Prevalence of labial frenum attachment and frenal morphology among patients reporting to Saveetha Dental College. J Clinical Dent. 2019;12(3):181-89. https://doi.org/10.4103/jisp.jisp_294_17 https://doi.org/10.4103/jisp.jisp_294_17... ]	India	500	20-70	UL and LL	79.6	2	16.4	0.8	1.2	0	0	0
	India	500	20-70	UL and LL	-	-	-	-	-	-	-	-
Sekar et al. (2019) [¹⁶16 Sekar R, Mungara MJ, Joseph E. To determine the prevalence of maxillary labial and mandibular lingual frenum and it’s relationship between the upper midline space and to clinically assess the maxillary labial frenum morphology in 3 to 14 years children of Chennai City. Gjra - Global J Res Anal. 2019; 8(2):136-140. https://doi.org/10.36106/GJRA https://doi.org/10.36106/GJRA... ]	India	951	03-14	L and l	86.4	6.3	4.6	0	0	2.4	0.2	0
	India	951	03-14	L and l	22.9	18.3	20.5	0	0	39.1	50	0
Biradar et al. (2020) [³¹31 Biradar SM, Patil AY, Kotnoor SS, Bacha S, Bijjaragi SC, Kattimani PT. Assessment of diverse frenal morphology in primary, mixed, and permanent dentition: a prevalence study. J Contemp Dental Pract. 2020;21(5): 562-567. https://doi.org/10.5005/jp-journals-10024-2794 https://doi.org/10.5005/jp-journals-1002... ]	India	1.800	3-17	UL	69.33	5.61	12.11	-	0.55	11.27	0.72	0.38
	India	1.800	3-17	UL	-	-	-	-	-	-	-	-
Rathod et al. (2020) [⁴³43 Rathod S, Bawankar PV, Chikahale P, Bidwaikar A. Evaluation of variations in morphology and attachment of frenum in diverse population - A cross-sectional study. Clin Epidemiol Global Health. 2020;8:1094-97. https://doi.org/10.1016/j.cegh.2020.03.026 https://doi.org/10.1016/j.cegh.2020.03.0... ]	India	400	20-40	UL	77.44	1.75	15.79	0.50	1.75	0.50	0.75	1.50
	India	400	20-40	UL	-	-	-	-	-	-	-	-
Chaulagain et al. (2021) [³²32 Chaulagain R, Khanal N, Singh AK. Morphology of maxillary labial frenum in chepang community of Chitwan. J Nepal Health Res Council. 2021;19(50):185-188. https://doi.org/10.33314/jnhrc.v19i1.3475 https://doi.org/10.33314/jnhrc.v19i1.347... ]	Nepal	102	≤10-60	UL	72.5	7.8	19.6	0	0	0	0	0
		102	≤10-60	UL	-	-	-	-	-	-	-	-
		302	06-16	UL	83.2	6.5	7.3	0.3	1.2	1.5	0	0
Joshi et al. (2021) [⁴⁴44 Joshi U, Pradhan M, Neupane A, Lawanju N, Khadka N, Chaulagain R. Variations in maxillary frenal morphology in a sample of newari children of Bhaktapur. J Nepalese Soc Periodontol Oral Implantol. 2021;5(9):34-8. https://doi.org/10.3126/jnspoi.v5i1.38181 https://doi.org/10.3126/jnspoi.v5i1.3818... ]		302	06-16	UL	-	-	-	-	-	-	-	-
Patel et al. (2021) [⁴⁵45 Patel J, Parikkh H, Duseja S, Agrawal C, Dholakia P, Pathak V. Variations in the attachment and morphology of maxillary labial frenum in diverse population of gujarat: an observational study. J Res Adv Dent. 2021;11(3):336-41.]	India	1000	18-30	UL	84.3	3.5	8.3	0	0	0.2	3.7	0

					-	-	-	-	-	-	-	-
Kilinc et al. (2021) [⁵¹51 Pereira RMA, Marangonn Jr. H, Tedesco TK, Alencar CJF, Moura-Netto C, Mello-Moura ACV. Longitudinal evaluation of diastema closure in patients submitted to labial frenectomy in different phases of the mixed dentition: a historical cohort. J Indian Soc Pedodont Prev Dent. 2021;39(2):159-63. https://doi.org/10.4103/jisppd.jisppd_397_20 https://doi.org/10.4103/jisppd.jisppd_39... ]	Turkey	1023	2-65	UL	66.9	17.0	5.7	8.8	0.9	0.3	0.4	-
					-	-	-	-	-	-	-	-

Study	Country	Sample size	Age (years)	Location of frenum	Frenal attachment (%)
					Diastema (%)
					1	2	3	4
Placek et al. (1974) [¹⁷17 Placek M, Miroslav S, Mrklas L. Significance of the labial frenum attachment in periodontal disease in man.part 1. classification and epidemiology of the labial frenum attachment. J Periodontol. 1974;45(12): 891-894. https://doi.org/10.1902/jop.1974.45.12.891 https://doi.org/10.1902/jop.1974.45.12.8... ]	Czech Republic	465	15-40	UL and LL	46.5	34.3	3.1	16.1
	Czech Republic	465	15-40	UL and LL	-	-	-	-
Ruli et al. (1997) [¹¹11 Ruli LP, Duarte CA, Milanezi LA, Perri SHV. Frênulo labial superior e inferior: estudo clínico quanto a morfologia e local de inserção e sua influência na higiene bucal. Rev Odontol Univ São Paulo. 1997;11(3). https://doi.org/10.1590/S0103-06631997000300008 https://doi.org/10.1590/S0103-0663199700... ]	Brazil	100	19-26	UL and LL	15	77	7	1
	Brazil	100	19-26	UL and LL	-	-	-	-
Braga et al. (2006) [¹²12 Braga AT, Quelemes PV, Moura WL, Moura WL. Descrição da morfologia dos frênulos labiais superiores em escolares de Teresina. Rev Cir Traumatol Buco-Maxilo-facial. 2006;7(3):59-64.]	Brazil	300	7-10	UL	46	32	18.6	3.3
	Brazil	300	7-10	UL
Gusmão et al. (2009) [¹³13 Gusmão ES, Souza PFJC, Vasconcelos RB, Claus RP, Cimões R, Coelho RS. Inserção e morfologia dos freios labiais. Odontol Clínico Científ. 2009; 8(2):133-139.]	Brazil	261	18- 72	UL and LL	60.9	34.1	4.2	0.8
	Brazil	261	18- 72	UL and LL	-	-	-	-
Boutsi & Tatakis (2011) [³³33 Boutsi EA, Tatakis DN. Maxillary labial frenum attachment in children. Int J Paediatr Dent. 2011 Jul;21(4):284-8. https://doi.org/10.1111/j.1365-263X.2011.01121.x https://doi.org/10.1111/j.1365-263X.2011... ]	Greece	226	1-18	UL	10.2	41.6	22.1	26.1
	Greece	226	1-18	UL	-	-	-	-
Upadhyay & Ghimire (2012) [¹⁹19 Upadhyay S, Ghimire N. Attachment of maxillary labial frenum in nepalese children. Orthod J Nepal. 2012;2(1):28-31. https://doi.org/10.3126/ojn.v2i1.9291 https://doi.org/10.3126/ojn.v2i1.9291... ]	Nepal	198	1-14	UL	13.6	61.1	17.2	8.1
	Nepal	198	1-14	UL	-	-	-	-
Christabel & Gurunathan (2015) [²¹21 Christabel SL, Gurunathan D. Prevalence of type of frenal attachment and morphology of frenum in children, Chennai, Tamil Nadu. World J Dent. 2015;6(4):203-207. https://doi.org/10.4103/jisp.jisp_294_17:10.4103/jisp.jisp_294_17. https://doi.org/10.4103/jisp.jisp_294_17... ]	India	931	3-12	UL	38.8	49.5	9.8	1.9
	India	931	3-12	UL
Khursheed et al. (2015) [³⁵35 Khursheed DA, Zorab SS, Zardawi FM, Ali AJ, Talabani RM. Prevalence of labial frenum attachment and its relation to diastema and black hole in kurdish Young population. J Dental Medical Sci. 2015;14(9):97-100. https://doi.org/10.9790/0853-149197100 https://doi.org/10.9790/0853-149197100... ]	Iraq	279	10-30	UL	12.5	68.8	16.4	2.1
	Iraq	279	10-30	UL	-	-	-	-
Ribeiro et al. (2015) [¹⁴14 Ribeiro ILA, Fernandes TL, Trigueiro DA, Souza CFM, Medeiros JMD. Avaliação dos padrões de morfologia e inserção dos freios labiais em pacientes da clínica-escola de odontologia do Centro Universitário de João Pessoa - PB. Rev Odontol UNESP. 2015;44(5):268-272. https://doi.org/10.1590/1807-2577.1081 https://doi.org/10.1590/1807-2577.1081... ]	Brazil	385	10-72	UL and LL	75.8	19.2	1.8	3.2
	Brazil	385	10-72	UL and LL	-	-	-	-
Bervian et al. (2016) [¹⁵15 Bervian J, Cazarotto F, Perussolo B, Patussi EG, Pavinatto LCB. Description of the Upper Labial Frenulum Characteristics in Preschool Children of Passo Fundo, Brazil. Braz Res Pediatric Dent Integr Clinic. 2016;16(1):351-357. http://dx.doi.org/10.4034/PBOCI.2016.161.37 https://doi.org/10.4034/PBOCI.2016.161.3... ]	Brazil	304	0-6	UL	21.4	51	21	6.6
	Brazil	304	0-6	UL	-	-	-	-
Jindal et al. (2016) [²²22 Jindal V, Kaur R, Goel A, Mahajan A, Mahajan N, Mahajan A. Variations in the frenal morphology in the diverse population: a clinical study. J Indian Soc Periodont. 2016;20(3):320-323. https://doi.org/10.4103/0972-124X.182598 https://doi.org/10.4103/0972-124X.182598... ]	India	500	16-40	UL	66	28.4	2.4	3.2
	India	500	16-40	UL	-	-	-	-
Sękowska & Chałas (2016) [⁶6 Sękowska A, Chałas R. Diastema size and type of upper lip midline frenulum attachment. Folia Morphol. 2017; 76(3):501-505. https://doi.org/10.5603/FM.a2016.0079 https://doi.org/10.5603/FM.a2016.0079... ]	Poland	102	-	UL	41.1	28.4	14.7	15.6
	Poland	102	-	UL	17.3	25	26.9	30.8
Niazi et al. (2017) [²⁵25 Niazi M, Manzoor N, Sajjad S, Qazi HS. Morphological and attachment variations of median maxillary labial frenum. J Pakistan Orthop. 2017;9(1):19-23.]	Pakistan	600	5-63	UL	38.8	58.5	2.1	0.5
	Pakistan	600	5-63	UL	-	-	-	-
Karam et al. (2018) [³⁶36 Karam BM, Ahmed AG, Kadir SK, Qasim HJ, Mohammed GN. Upper labial frenum attachment and medium diastema; comparative study between Kurdish and arab teenagers in Zakho city, Kurdistan, Iraq. Duhok Med J. 2018;12(1):31-40. https://doi.org/10.31386/dmj.uod.18.12.1.4 https://doi.org/10.31386/dmj.uod.18.12.1... ]	Iraq	307	15-19	UL	35.1	57.9	4.8	1.9
	Iraq	307	15-19	UL	-	-	-	-
Rajkarnikar et al. (2018) [³⁴34 Rajkarnikar J, Khanal S, Acharya J. Prevalence and variations of the maxillary labial frenum in children, adolescents and adults. Nepal Med College J. 2018;20(1-3):94-97.]	Nepal	356	1 - > 35	UL	70.5	28.4	0.8	0.3
	Nepal	356	1 - > 35	UL	-	-	-	-
Jonathan et al. (2018) [⁸8 Jonathan PT, Himani T, Abhiruchi G, Virat G, Neha G. Maxillary labial frenum morphology and midline diastema among 3 to 12-year-old schoolgoing children in Sri Ganganagar city: a cross-sectional study. J Indian Soc Pedod Prev Dent. 2018; 36(3):234-239. https://doi.org/10.4103/JISPPD.JISPPD_51_18. https://doi.org/10.4103/JISPPD.JISPPD_51... ]	India	1200	3-12	UL	47.5	38.1	0	14.2
	India	1200	3-12	UL	12.2	22.2	0	65.5
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	Malaysia	152	2-15	UL	-	-	-	-
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		102	≤10-60	UL	-	-	-	-
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	Nepal	140	12-71	UL	-	-	-	-

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[1] Correspondence to: R Cimões. E-mail: renata.silveira@ufpe.br.