From Volume 47, Issue 11, December 2020 | Pages 951-955
Effective communication is required when referring patients for extractions and surgical procedures. There are multiple notation systems used for the identification of teeth, making communication for dental extractions challenging. The aim of this article is to provide an overview of the methods available to identify teeth and to propose a novel technique to identify erupted teeth for extraction.
Dental extractions are a common procedure carried out by many dental professionals. Often, prior to a dental extraction or surgical procedure, a referral is made from one dental professional to another. It is stated by the General Dental Council that, if you request a colleague to provide a treatment, you should make the request clear and give your colleague all the information they need.1 Effective communication when referring patients for extractions and surgical procedures is required.
Failure in communication and tooth identification when referring patients for dental extraction can contribute to surgical errors. Wrong tooth extraction is considered a ‘never event’ by the National Health Service and is regarded as equivalent to ‘wrong leg amputation.’ In 2016/17, 24% of wrong-site surgery was made up of wrong tooth/teeth extractions.2 This article summarizes the present methods used for tooth identification and proposes a novel method to help dental professionals improve communication and, therefore, theoretically reduce the risk of a ‘never event.’
Orthodontic extractions are commonly known to be high risk for wrong tooth extractions. The British Orthodontic Society has set guidelines to assist practitioners in minimizing the risk of wrong tooth extractions, particularly when referrals are made to another practitioner who will be carrying out the treatment (Appendix 1).
Dental notation techniques include the following:
The use of long-hand wording to identify teeth can be cumbersome and inconvenient, when used day-to-day by dentists when writing up patient records and referral letters. Dental notation is a much quicker and simpler way of recording dentition and communicating between clinicians. The following is a summary of the common dental notations used to identify the dentition.
The oldest notation system that is commonly used was introduced by Hungarian dentist, Adolf Zsigmondy, in 1861.5 A few years later, in 1870, Corydon Palmer, in the USA, unaware of previous publications, described a similar symbolic system.6 The Palmer notation uses a cross structure (+) to denote the four quadrants of the mouth and the position of the teeth within them (Figure 1).7 Permanent teeth are numbered 1–8, commencing in the midline, and deciduous teeth are lettered A–E.7 Individually, the dentition is represented by the ‘L-shaped symbol’.8,9 For example, V describes the lower left primary first molar. By 2000, the traditional Palmer notation created difficulties in its use with word processing, computerized records and HTML, the programming language of the internet.10 The Palmer notation evolved to a more computer friendly format, the alphanumeric system.7 The four quadrants of the mouth were given a short-hand upper left (UL), upper right (UR), lower left (LL), and lower right (LR), followed by tooth number as assigned under the Palmer notation.
This is the two-digit system, originally described by Dr Jochen Viohl of Berlin in 1966.11,12 At the 58th annual meeting of the Fédération Dentaire Internationale (FDI) in 1970, it was proposed that the two-digit system be used worldwide,11 including the World Health Organization.13 It was believed to be a superior system in being easier to teach, understand and communicate through modern technology.11 The first digit represents the quadrants and is numbered from the top right in a clockwise fashion when looking at the patient, subsequently the second digit represents the tooth within the quadrant. For example, the maxillary right quadrant is assigned the number 1. The teeth within each quadrant are assigned a second digit from 1 through 8, with 1 starting with the central incisor and 8 being the third molar (Figure 2). It should be noted that the digits are pronounced separately, for example, tooth 15 (maxillary right second premolar) is ‘one-five’ not ‘fifteen’.
The universal numbering system was proposed by a German dentist, Julius Parreidt, in 1882.11 It is the most commonly used notation system in the USA. It uses consecutive integers (Figure 3), numbered from 1 (upper right third molar) through to 16 (upper left third molar). Moving clockwise, the mandibular teeth are numbered from 17 (lower left third molar) through to 32 (lower right third molar). Primary teeth are labelled A to T using upper case letters.14
Supernumerary dentition presents as a challenge in notation and often has to be described anatomically, which may not always be clear. The prevalence of permanent supernumerary teeth ranges from 0.5% to 5.3%.15,16 Multiple supernumerary teeth are usually observed in patients with developmental disorders, such as cleft lip and palate, cleidocranial dysplasia, Ehlers-Danlos type IV. 17,18,19,20 Having no universally accepted method of notation that is easily understood can lead to confusion and delay when communicating treatment plans between dental professionals. Supernumerary teeth are best described in words along with clinical photography (Figure 4) or a copy of a radiograph.
The availability of multiple notation systems increases the risk of miscommunication, especially between the universal and FDI system, which both have a two-digit notation.21,22 When a patient is referred for a dental extraction, Dyke and Sandler suggest the use of a referral letter and an annotated dental panoramic tomograph.23 In this technique, the teeth to be extracted are identified with a cross on a radiograph, such as a dental panoramic tomograph (DPT) (Figure 5). This is particularly useful in cases where there are unerupted teeth to be removed. However, the tooth to be removed may not always be clear on a DPT in cases where there is crowding or supernumerary teeth are involved. In circumstances such as these, a clinical photograph can be annotated with an ‘X’ to identify erupted teeth planned for extraction (Figure 6).
Annotated radiographs and photographs are effective in ensuring the clinician understands the procedures required, and it aids the consent process. It can also act as a visual reminder to the clinician and the rest of the team during the clinical procedure. This will theoretically reduce the risk of error at the stage of the referral process.
The identification of teeth for extraction can be challenging. This is particularly difficult in cases where the patient is in the mixed dentition, has hypo- or hyperdontia, unusual dental anatomy, transpositions or ectopic teeth. In cases such as these, the authors propose the use of intra-oral marking of the teeth to be extracted.
In this technique, the principles of the ‘WHO surgical safety checklist’ are applied to the patient's dentition that is planned for extraction. The marking of dentition is challenging as the teeth are often immersed in saliva, making use of a marking pen impractical. To overcome this barrier, the authors suggest a blob of an adhesive restorative material, blue compomer, to be applied on the dentition planned for removal. The blue compomer is made up of glass-ionomer cements and photo-polymerized resin components, which can be set by a light cure controlled by the operator. The blue compomer can be masked by being placed palatally on the patient's dentition, particularly if planning to refer the patient to another specialty. Current guidelines and methods do not specify the marking of teeth intra-orally. However, the marking of a surgical site and the procedure are essential criteria in the WHO surgical safety checklist that aims to prevent adverse events occurring in hospital.24 The teeth to be extracted can be marked by the referring dental professional or can be marked by the operator at the time of the procedure. This technique does require treatment planning by the practitioner to take additional time to place the blue compomer on the teeth, which may prove to reduce wrong tooth extractions significantly, and thereby improve operator confidence.
The intra-oral dental marking technique is demonstrated by a 14-year-old girl who had a class III incisor relationship on a skeletal III base, complicated by palatal positioned UR3, UL3, small UR2, UL2 and retained URC, ULC. As part of her orthodontic treatment plan, the patient required the extraction of her retained URC and ULC. In addition to the orthodontist's referral letter, which described the teeth to extracted in words, supplemented by dental charting, the teeth to be extracted were also highlighted by intra-oral bonding of blue compomer (Figure 7) to the URC and ULC (3M Unitek Transbond™ Plus). This was carried out by the referring orthodontist. The use of the intra-oral marking technique was useful for the clinician receiving the referral. In addition, the family felt reassured by the process.
The use of intra-oral dental marking will theoretically reduce the risk of errors at every stage of the referral process and also the surgical procedure.
The identification of teeth for dental extraction can be challenging. This demands effective communication and identification techniques. This article has summarized the methods available to identify teeth for dental extractions. A novel method for the identification and communication of teeth in challenging cases has also been demonstrated.
