Clinical consequences of premature loss of primary molars: a narrative literature review

The premature loss of primary molars in children during the transition from primary to early mixed dentition is a dental condition that may affect the development of the masticatory system and the eruption of permanent teeth. This study is a narrative critical review of the literature aimed at analyzing and synthesizing the clinical consequences associated with premature loss of primary molars in children. A structured literature search was conducted in PubMed, Scopus, and SciELO databases for studies published between 2009 and 2024 in English and Spanish. A combination of Medical Subject Headings (MeSH) terms and free-text keywords was used to identify relevant studies. Eligibility criteria were applied to select studies involving children during the transition from primary to early mixed dentition that reported clinical consequences of premature loss of primary molars. The selected evidence was critically analyzed and narratively synthesized. A total of 58 records were identified, of which 19 studies were included in the final synthesis. The included studies reported clinical consequences such as loss of arch space, occlusal alterations, early eruption of permanent teeth, dental crowding, mesial tipping of permanent molars, and tooth impaction. The effects varied depending on the location and type of molar affected. In conclusion, premature loss of primary molars is associated with clinically significant alterations in occlusion and space maintenance during mixed dentition development.

Early loss; Premature loss; Primary molars; Deciduous molars

[1] El-Motayam AK, Hassan MA, Sadek MM, Fathalla R, Wahba N, Mahmoud R, et al. Extraction of first primary molars and significance of space loss: a systematic review and meta-analysis. BMC Oral Health. 2026; 26: 611.

[2] Shakti P, Singh A, Purohit BM, Purohit A, Taneja S. Effect of premature loss of primary teeth on prevalence of malocclusion in permanent dentition: a systematic review and meta-analysis. International Orthodontics. 2023; 21: 100816.

[3] Santos AGC, Machado CV, Telles PDS, Rocha MCBS. Early loss of deciduous molars in children assisted by the School of Dentistry of the University of Bahia. Odontologia Clínico-Científica. 2013; 12: 189–193. (In Portuguese)

[4] Macena MC, Tornisiello Katz CR, Heimer MV, de Oliveira e Silva JF, Costa LB. Space changes after premature loss of deciduous molars among Brazilian children. American Journal of Orthodontics and Dentofacial Orthopedics. 2011; 140: 771–778.

[5] Gandhi JM, Gurunathan D. Short- and long-term dental arch spatial changes following premature loss of primary molars: a systematic review. Journal of Indian Society of Pedodontics and Preventive Dentistry. 2022; 40: 239–245.

[6] Díaz-Valdés K, Iglesias-Iglesias MA, Fernández-Canino A, Pérez-Díaz MK, López-González M. Premature loss of primary teeth in school children. Revista de Ciencias Médicas de Pinar del Río. 2024; 28: e6173. (In Spanish)

[7] Gomide RT, Frencken JE, Leal SC, Kuijpers-Jagtman AM, Faber J. Impact of proximal cavities and primary molar absence on space in the dental arches. PeerJ. 2020; 8: e8924.

[8] Kobylińska A, Piekoszewska-Ziętek P, Gozdowski D, Turska-Szybka A, Olczak-Kowalczyk D. Spatial changes in the dental arch after premature extraction of the first primary molar: a 12-month observational study. New Medicine. 2019; 23: 96–104.

[9] Lin YJ, Lin YT. Long-term space changes after premature loss of a primary maxillary first molar. Journal of Dental Sciences. 2017; 12: 44–48.

[10] Lin YT, Lin WH, Lin YTJ. Twelve-month space changes after premature loss of a primary maxillary first molar. International Journal of Paediatric Dentistry. 2011; 21: 161–166.

[11] Cernei ER, Mavru RB, Zetu IN. Axial modifications of permanent lower molars after premature losses of temporary molars. Medical-Surgical Journal of the Society of Physicians and Naturalists, Iaşi. 2016; 120: 178–185.

[12] Cernei ER, Maxim DC, Zetu IN. The influence of premature loss of temporary upper molars on permanent molars. Medical-Surgical Journal of the Society of Physicians and Naturalists, Iaşi. 2015; 119: 236–242.

[13] Heidari A, Mokhtari S, Hamrah MH, Tavana Z, Heydarigoojani M, Tavana N. Investigating the factors affecting the need for unilateral space maintainer for first primary molars in late mixed dentition. BioMed Research International. 2022; 2022: 7604144.

[14] Park K, Jung DW, Kim JY. Three-dimensional space changes after premature loss of a maxillary primary first molar. International Journal of Paediatric Dentistry. 2009; 19: 383–389.

[15] Petcu A, Maxim A, Haba D. Correlation between the lower first permanent molar axis and the premature loss of temporary molars. Medical-Surgical Journal of the Society of Physicians and Naturalists, Iaşi. 2009; 113: 1253–1257. (In Romanian)

[16] Pokorna H, Marek I, Kucera J, Hanzelka T. Space reduction after premature loss of a second deciduous molar: a retrospective study. IOSR Journal of Dental and Medical Sciences. 2016; 15: 1–8.

[17] García Y, Da Silva L, Medina A, Contreras O. Effect of the premature loss of primary molars over the incisal horizontal relation. Revista De Odontopediatría Latinoamericana. 2011; 1: 49–57. (In Portuguese)

[18] Warkhandkar A, Habib L. Effects of premature primary tooth loss on midline deviation and asymmetric molar relationship in the context of orthodontic treatment. Cureus. 2023; 15: e42442.

[19] Alexander SA, Askari M, Lewis P. The premature loss of primary first molars: space loss to molar occlusal relationships and facial patterns. The Angle Orthodontist. 2015; 85: 218–223.

[20] Alnahwi HH, Donly KJ, Contreras CI. Space loss following premature loss of primary second molars. General Dentistry. 2015; 63: e1–e4.

[21] Bindayel NA. Clinical evaluation of short term space variation following premature loss of primary second molar, at early permanent dentition stage. Saudi Dental Journal. 2019; 31: 311–315.

[22] Lucas-Rincón SE, Robles-Bermeo NL, Lara-Carrillo E, Scougall-Vilchis RJ, Pontigo-Loyola AP, Rueda-Ibarra V, et al. Interproximal caries and premature tooth loss in primary dentition as risk factors for loss of space in the posterior sector: a cross-sectional study. Medicine. 2019; 98: e14875.

[23] Mosharrafian S, Baghalian A, Hamrah MH, Kargar M. Clinical evaluation for space maintainer after unilateral loss of primary first molar in the early mixed dentition stage. International Journal of Dentistry. 2021; 2021: 3967164.

[24] Kaklamanos EG, Lazaridou D, Tsiantou D, Kotsanos N, Athanasiou AE. Dental arch spatial changes after premature loss of first primary molars: a systematic review of controlled studies. Odontology. 2017; 105: 364–374.

[25] Zhao J, Jin H, Li X, Qin X. Dental arch spatial changes after premature loss of first primary molars: a systematic review and meta-analysis of split-mouth studies. BMC Oral Health. 2023; 23: 430.