Sys Rev Pharm 2021;12(2):493-499 A multifaceted review journal in the field of pharmacy 493 Systematic Reviews in Pharmacy Vol 12, Issue 2, Jan-Feb 2021 The Effect of Thumb Sucking Habit on Children’s Dentomaxillofacial Development: A Systematic Review Harun Achmad a , Eriska Riyanti b , Arni Irawaty Djais c , Irene Edith Rieuwpassa d , Risti Saptarini Primarti b , Sasmita M. Arief e a. Department of Pediatric Dentistry, Faculty of Dentistry, Hasanuddin University, Indonesia b. Department of Pediatric Dentistry, Faculty of Dentistry, Padjadjaran University, Indonesia c. Department of Periodontology, Faculty of Dentistry, Hasanuddin University, Indonesia d. Department of Oral Biology, Faculty of Dentistry, Hasanuddin University, Indonesia e. Clinical Dental Student of Faculty of Dentistry, Hasanuddin University, Indonesia ABSTRACT Oral bad habits are one of the major etiologic factors which will leads to malformation in dento- facial structures, teeth malposition, respiratory disorder, difficulty speaking, muscle imbalances, and face psychological problems. Thumb sucking is the most common oral bad habit in children that can be grouped under a list of habits known as non-nutritive sucking habits. The reported incidence of thumb sucking is between 13% and 100% in some societies. The oral habit may continue to 3–4 years and will stop automatically. If the habit continues whilst the permanent dentition is becoming established, a diverse variety of approaches include advice, removal of the comforting object, fitting an orthodontic appliance to interfere with the habit, or behavior modification techniques are needed. The aim of this study is to determine the effect of thumb sucking habit on children’s dentomaxillofacial development. Data collection was carried out by searching the literature on the article search site, Pubmed, which was published from 2011 to 2020, the search was carried out in December 2020. The full-text articles in the remaining 46 articles were re-analyzed and excluded 36 articles and produced 10 articles which were then entered into the analysis. Based on this systematic literature review shows that thumb sucking can cause an impact on the muscles and facial development patterns in children, as well as impaired growth and development in the dentomaxillofacial. Keywords: Thumb Sucking; Children; Dentomaxillofacial Corresponding Author: harunachmader@gmail.com Introduction A habit is a routine of behavior that is repeated regularly and tends to occur unconsciously, repetitive action that is being done automatically. Oral bad habits are one of the major etiologic factors which will leads to malformation in dento- facial structures, most frequent cause of these malformations mostly seen in the early childhood and mixed dentition stages. 1 Oral bad habits that are abnormal often associated with disorders of growth of the jaw, teeth malposition, respiratory disorder, difficulty speaking, muscle imbalances, and face psychological problems. 2 Thumb sucking is the most common oral bad habit in children that can be grouped under a list of habits known as non-nutritive sucking habits. The incidence of thumb sucking can be very variable depending on the geographic area. The reported incidence of thumb sucking is between 13% and 100% in some societies. The prevalence of this habit is decreased as age increases. 3 Thumb sucking is a common childhood habit or behavior that is considered normal up to the age of 3 to 4 years. Prevalence of thumb sucking habit was found to be 14% in six years-old children, and 6% in children 11 years old. 4 A Swedish study showed an 82% incidence of non-nutritive sucking behaviors during the first five months of life. Another study done in the U.S. showed a 73% incidence of non–nutritive sucking habits in children between 2 and 5 years. Studies have shown the presence of a digit or pacifier sucking habit in about 48% of children at 4 years of age and 12.1% in children older than 7 years. The habit persists in 1.9% of 12-year-old children. 5 Most children leave this harmless habit before the age of two without any worries or interventions but the sucking habit in some children is so severe or repeated that it becomes a problem. Sucking a thumb is a natural reaction in children that may be beneficial or harmful. Sucking a thumb gives a sense of safety or joy to the infants; and helps them to better understand the world around themselves. On the other hand, thumbs that placed inside the mouth exert force on the tissues, thus creating physical changes as dentomaxillofacial abnormalities. Deleterious habitual patterns of muscle behaviour, often are associated with perverted or impeded osseous growth, tooth malposition, disturbed breathing habits, difficulties in speech, imbalance the facial musculature and psychological problems. 6 Thumb