“Why I don’t have a permanent tooth?”

One of the most difficult conversations I have with a parent is explaining that their child does not have a permanent adult tooth. A congenitally missing tooth (CMT), also diagnosed as hypodontia, dental agenesis, or congenital dental aplasia, is not only the most common dental issue but the costliest. Treatment for this involves a long-term, multidisciplinary approach with orthodontics, maxillofacial surgery, periodontics, and prosthodontics lead by your “quarterback,” the general dentist. If left untreated, functional issues, reduced chewing, poor speech, unfavorable appearance and poor self-esteem can develop.

Third molars are the most commonly missing tooth, with 20-30% of the population affected, followed by mandibular second premolars, maxillary lateral incisors and mandibular central incisors. Genetic factors, genetic syndromes, physical obstruction, limited space, functional abnormalities and failure for programmed cells to initiate growth are some of the causes. In the case of genetic syndromes, patients usually fail to develop several teeth and evidence based studies have found a predisposition to colorectal and ovarian cancers. Researches have postulated that failure to develop 3rd molars may be a process of evolution. Studies assessing the size of cranial base, maxilla, mandibular and the craniofacial complex discovered that patients with congenitally missing molars had a smaller jaw and face. For those of our readers who never developed 3rd molars, please feel free to inform your friend or neighbor that perhaps you are just more evolved!

The complexity of CMT is not in understanding the cause and diagnosis, but in the treatment, which involves a multidisciplinary approach requiring both resilience and financial resources by the patient. If you are missing 3rd molars be grateful that you will not need to endure this rite of passage. In the case of congenitally missing second premolars, the baby tooth does not fully erupt causing the tooth in front and behind drift towards each other causing food impaction, decay and loss of space for replacing the missing tooth. Orthodontics helps maintain the space, potentially increasing the longevity of the baby tooth and allowing for future implant placement. As for the missing lateral incisor, considerations for esthetics are of utmost importance. When a child is missing a front tooth, the primary concern for the parent following orthodontics is what will replace the tooth for family photos coming up. In the past, the only missing tooth replacement option was a removable partial (aka “flipper” which is similar to a retainer with a false tooth attached). Parents can understand how trying this type of appliance can be the first time your teenager throws this away! Most recent studies have found that this missing tooth replacement option may cause the adjacent roots to converge and close that space for a potential implant, resulting in the need for orthodontic retreatment. With the advent of adhesive dentistry and increased strength of porcelain, amazing esthetics can be accomplished with a minimally invasive bridge as a temporary solution until an implant can be placed once growth is complete.