A Narrative Review on Non-Invasive Diagnostic Tools for the Analysis of Dental Arches in Orofacial Cleft Patients

Background: It is necessary to analyze and monitor the facial growth of orofacial cleft patients. The documentation should therefore begin before and after primary surgeries. Technological evolution has transformed plaster models into 3D images through scanners that allow rational storage, manipulation, and rotation without the possibility of breakage or damage. Based on this fact, this narrative review aims to provide a feature on the three-dimensional tools available for the assessment of dental arches in children with orofacial cleft and mixed dentition. Material and Methods: Three databases were chosen (PubMed, ScienceDirect, and Scopus) and keywords were used to select papers. Results: During the database screening, 292 potentially relevant papers were found. After removing duplicates, titles, and abstracts, 32 papers presented qualifications for analysis. Through evaluating each document by reading it one by one, 24 papers fulfilled the eligibility criteria. Conclusions: It was concluded that digital tools—i.e., benchtop scanners which evaluate the dental arches of children with cleft lip, palate, and mixed dentition—are reproducible and reliable, without the use of ionizing radiation, allow storage, manipulation with sustainability, and help preserve the environment.

As such, it is necessary to analyze and monitor the facial growth of individuals with cleft lip and palate. Facial growth documentation should begin before primary surgeries and continue after until five years of age. In addition to the documentation already included in the protocols and in plaster models, 3D photos can aid in the measurements and analyses of dental arches and facial growth.
The literature describes intraoral photos for the purposes of analyzing occlusion indexes. Plaster models are the gold standard [7] and plaster model images have been analyzed with accuracy [8]. Both intraoral photos and plaster models have proved to be reliable and reproducible [9]. Technological evolution has changed plaster models into 3D images through the use of scanners [10] that allow rational storage, manipulation, and rotation without the possibility of breakage or damage. With the use of software to carry out the evaluations, instead of using a caliper and rulers [11], more accurate linear [12] and angular measurements are obtained. In addition to these, more accurate measurements of area [6], volume [3], superimpositions [13], and occlusal contacts [14] are also obtained. All of these help to better understand what happens with the growing dental arches of patients undergoing the rehabilitation process. The software's ability can be sufficiently precise and

Search Strategy
PubMed, Scopus, and ScienceDirect were chosen as the databases reviewed. Additionally, the narrative review included papers only in the English language. The following keywords were used: Children; Cleft Lip; Cleft Palate; Imaging, Three-dimensional; and Dental Arches.

Inclusion Criteria
All studies that presented quantitative assessments, such as research, multicenter studies, randomized clinical trials, and retrospective clinical studies, were included.

Selected Sample
-Maxillary dental arches of cleft lip and palate patients aged up to 12 years; -Optical devices, scanners, and stereophotogrammetry in order to reproduce 3D maxillary dental model; -Types of intervention, linear, angular, surface (area), volume measurements, and qualitative analysis of the occlusal index. Types of analysis of results, reliability, precision, repeatability (conventional vs. digital analysis), cross-sectional, and longitudinal analyses.

Study Selection
According to the inclusion and exclusion criteria, two examiners independently analyzed the titles and abstracts of the articles initially selected. The full texts were read whenever the title and abstract lacked sufficient information. This procedure avoided the exclusion of relevant papers. In the absence of consensus among the examiners considering the eligibility of some documents, a third reviewer participated in the scientific discussion.

Data Extraction
The examiners collected the following information after reading the full text of each paper: title, authors, year, and device were used to acquire the 3D image. Parameters were evaluated in the dental arches, anthropometric analysis software, selected sample, and type of study (either cross-sectional or longitudinal). All data collected were stored in a table (Microsoft Word 2019, Microsoft Corporation, Redmond, DC, USA). Figure 1 presents a flowchart of the paper selection process.
ing the eligibility of some documents, a third reviewer participated in the scientific discussion.

Data Extraction
The examiners collected the following information after reading the full text of each paper: title, authors, year, and device were used to acquire the 3D image. Parameters were evaluated in the dental arches, anthropometric analysis software, selected sample, and type of study (either cross-sectional or longitudinal). All data collected were stored in a table (Microsoft Word 2019, Microsoft Corporation, Redmond, Washington State, USA). Figure 1 presents a flowchart of the paper selection process.

Results
During the database screening, 292 potentially relevant papers were found. After removing duplicates and reading the titles and abstracts, 32 papers were selected for analysis. Eight papers were excluded after carefully reading of the text. Twenty-four scientific articles were selected from between 2007 and 2022. All the studies evaluated were of participants with cleft lip and palate, 23 evaluated a UCLP patient and the other BCLP. Twelve studies were longitudinal, and the other twelve were cross-sectional (Table 1). Twenty-three studies used a scanner to obtain three-dimensional virtual dental arches, and the other used stereophotogrammetry equipment. The 3Shape Orthodontic Scanner (Copenhagen, Denmark) was the most used model (14 articles, as shown in Table 2). Fourteen different types of software were used in the studies. Mirror imaging software (Canfield Scientific Inc., Parsippany, NJ, USA) was the most used computer program (used in 5 articles). Linear measures were the most quantified (14 articles), while project palatal curve and superimposition were the least evaluated (1 article for each parameter, as shown in Table 3). Six of the selected articles were included in the reproducibility analysis (5 articles: occlusal index and 1 article: palatal surface area). Among these, one evaluated the accuracy (parameter assessed: area), while another evaluated the validity (parameter assessed: occlusal index, as shown in Table 4).

Results
During the database screening, 292 potentially relevant papers were found. After removing duplicates and reading the titles and abstracts, 32 papers were selected for analysis. Eight papers were excluded after carefully reading of the text. Twenty-four scientific articles were selected from between 2007 and 2022. All the studies evaluated were of participants with cleft lip and palate, 23 evaluated a UCLP patient and the other BCLP. Twelve studies were longitudinal, and the other twelve were cross-sectional (Table 1). Twenty-three studies used a scanner to obtain three-dimensional virtual dental arches, and the other used stereophotogrammetry equipment. The 3Shape Orthodontic Scanner (Copenhagen, Denmark) was the most used model (14 articles, as shown in Table 2). Fourteen different types of software were used in the studies. Mirror imaging software (Canfield Scientific Inc., Parsippany, NJ, USA) was the most used computer program (used in 5 articles). Linear measures were the most quantified (14 articles), while project palatal curve and superimposition were the least evaluated (1 article for each parameter, as shown in Table 3). Six of the selected articles were included in the reproducibility analysis (5 articles: occlusal index and 1 article: palatal surface area). Among these, one evaluated the accuracy (parameter assessed: area), while another evaluated the validity (parameter assessed: occlusal index, as shown in Table 4).

Discussion
In the last decade, technology and innovation have also assumed a prominent position in dentistry by providing researchers with more accurate measurements in growth analysis and dental arch evaluation. The study of orofacial development and the growth of patients with cleft lip and palate is widely evaluated before and after primary surgeries [1][2][3][4][5][6][18][19][20][21][22]25,[30][31][32] and for the follow-up of specific therapies [1,24]. This orofacial growth and development evaluation aims at better techniques and surgical time due to the fact that gold standard surgical protocols have not yet been described.
The image acquisition can be obtained from benchtop scanning to taking pictures. Bench scanners are the most used because they have certified technology with an affordable price. This type of equipment aims to digitize impressions, or dental models, in order to obtain 3D images, provide storage, manipulation, and the exchange in information between research centers for the purposes of cross-sectional and/or longitudinal studies as well as clinical follow-ups. However, non-dental scanners have been used as digitizers [26][27][28][29].
The software can capture measurements of different magnitudes, including the analysis between three points (angles), between two points (area), and also three planes (volume). The analysis of the area measurements reveal the maxillary segments' size, the arch's total development, and the potential palate growth [23]. Volume is a broader measurement, considering the whole maxilla from the palate to the ridge and in covering all teeth. The volume is assessed from image superimposition, a relevant tool in the evaluation of craniofacial development, bone deficiency in the cleft region, and in monitoring the effect of rehabilitation protocols in patients with cleft lip and palate [3]. This technology, either intraoral or model scanning, proved to be a minimally invasive method without the use of ionizing radiation [36].

Conclusions
Based on the eligible studies of this narrative review, it is concluded that using digital tools and benchtop scanners in order to evaluate the dental arches of children with cleft lip and palate, at a mixed dentition, are reproducible, reliable, possible without the use of ionizing radiation, capable of allowing storage, allow manipulation with sustainability, and are able to assist with environment preservation.