Occlusal Analysis in Natural Dentition: Systematic Review

Abstract This study aimed to evaluate the effectiveness of conventional occlusal analysis in contrast with digital occlusal analysis in natural dentition. Occlusal analysis allows the identification of normal and abnormal occlusal contact points that alter the craniomandibular cervical system. We searched for articles with keywords [[dental occlusion]], [[natural dentition]], [[occlusal adjustment]], [[Immediate Complete Anterior Guidance Development]] [[mastication]], [[bite force]], [[premature contact]], [[occlusal balance]] [[articulating paper]]], [[spray]], [[Occlusal contacts]], and [[bite strength]]. They were considered observational , odds ratio and case control studies. We found 189 items. After evaluating the abstracts and full texts of the articles, 10 papers met the inclusion criteria. It was found that occlusal analysis allows the identification of the relationship between poor occlusion and the sensitivity of the teeth due to occlusal trauma, which is also related to temporomandibular joint pain in dynamic occlusion. The contacts of greater strength were observed in nonfunctional cusps, 48%, without ruling out the functional cusps, 24%. Despite being the universal method of occlusal control to date, the use of joint paper, remains subjective compared to the digital occlusal control device. Posture is considered directly related to occlusal trauma and temporomandibular disorders; without proper occlusal analysis, a clear diagnosis of the patient's joint condition cannot be obtained. Digital occlusal analysis is more objective than traditional occlusal analysis.


Introduction
Occlusion is morpho-physiologically static, dynamic, and uniaxial and can be altered by modifications in the stomatognathic system, teeth, muscles, ligaments, and temporomandibular joint. 1,2Occlusive analysis allows the identification of normal and abnormal occlusal contact points.In occlusion, marks are used to indicate the location of contact points after asking the patient to make mandibular movements such as opening, closing, lateral movements (right and left), protrusion, and retrusion. 2Marks can be made by spray or paper.The fidelity of these systems depends on the operator's ability, the sensitivity of the marker, etc. 3,4 When thinner articulating paper is used, unnecessary wear on teeth can be prevented.Additionally, some commercial brands do not adhere to the thickness guidelines of occlusive paper. 5,6Computerized digital occlusal analysis appears to be a more precise method; it uses technological benefits to achieve the correct occlusal diagnosis, measure relative occlusal forces in static and dynamic mandibular positions, and generate three-dimensional graphics that identify the areas of greater or less pressure. 7espite the advantages of the digital method, articulating paper is the most used method by clinical dentists.By varying occlusal effects in endodontic teeth and utilizing digital or traditional occlusal analysis, 8 we determined that occlusal contact can be reduced with occlusal adjustment.A similar analysis of occlusal force is measured in overdentures in total edentulous patients, indicating greater force measured with a digital system in the posterior sector. 9Simultaneous occlusal contacts observed with articulating paper 10 and digital occlusal analysis 11 allow us to differentiate moments of occlusion and disocclusion, which appear visually on the teeth with the help of articulating paper, as well as in the digital occlusal analysis. 12The aim of this study is to evaluate the effectiveness of conventional occlusal analysis in contrast with digital occlusal analysis in natural dentition.Inclusion criteria were as follows: complete articles, dates of the articles, odds ratio, case-control with confidence interval (CI) lower and CI upper, and articles containing studies of occlusal pathology.In total, the keyword search returned n ¼ 189 articles from the database and additional records identified from other sources were n ¼ 10.Some articles were removed after they were found to be duplicate (n ¼ 115 records), and some were excluded for not presenting their information on occlusal pathologies, anterior guide, occlusal trauma, or papers that related to bad occlusion with   Occlusal Analysis in Natural Dentition Velasquez et al. 617

Methods
bruxism or temporomandibular disorders.Articles were narrowed down to 84 after screening and excluded 62 of these so that the total number of studies included in the qualitative synthesis was 22.The total number of studies included in the final analysis was 10 (►Fig. 1).This systematic review was carried out independently by two researchers different from the main one, specialists in the area of oral rehabilitation.Disagreements about study selection were resolved by consensus or intervention of the main researcher.Agreement of the selected articles by the two authors was calculated using kappa coefficient, which was 0.85.In all cases of concordance assessment, the response options were dichotomized to two response options: inclusion and exclusion.As a result, 115 articles were excluded.Of these remaining 84 articles, complete text could be not accessed in 62 articles, only the summaries, and the remaining 22 were completely reviewed by the principal investigator, excluding 25 articles for not meeting the selection criteria due to not adequately describing the clinical criteria of the diagnosis.A final total of 10 articles were obtained.
The authors (B.V.V.R., L.C.H.B., M.R.T., and V.M.C.) independently selected the titles and summaries, excluded duplicates and irrelevant articles, and considered only full-text articles.The date and names of all authors were included in the final review article.Any conflict with respect to inclusion and exclusion criteria was resolved by the third and fourth authors (A.M.S., E.A.).The data extraction procedure was evaluated according to the criteria of all authors.Articles are classified by the author/year, study objective, study type, methodology, the results (standard mean and deviation), and conclusions.

Results
To analyze the research articles, the risk of bias was assessed.Bias is assessed as a judgment for individual elements from domains (selection, reporting, and other) (►Table 1).When assessing to clarify the gold standard, the collection of information was not homogeneous between the studies, and none reported having considered the reliability and validity of the clinical aspects.The classification system had a dental evaluation to classify patients and was able to apply conventional occlusal analysis or digital analysis.Methods varied between questionnaires (with dichotomous yes/no, multiple-choice, or visual analog scale responses), interviews, the use of immediate complete anterior guidance development, and digital occlusal analysis (►Table 2).Acceptable intra-and interexaminer reliability considered the previous training of examiners prior to clinical measurements; in many of the studies, the number of examiners was unclear and appeared to vary between one, two, or more.The use of adequate samples varied widely in the number of subjects, although a good number of the reports included more than 30 participants.Samples also varied in age ranges, and some of the studies included patients younger than 30 years, while others included patients over 50 years.When assessing replicability of the studies, the studies that presented similar conclusions did not necessarily obey a replicability of the responses of the patients examined in the different studies, which was due to the heterogeneity of the designs and other methodological shortcomings.Without an appropriate occlusal analysis, a clear diagnosis of the patient's joint condition cannot be obtained (►Table 3).

Discussion
Various methods and materials found in the literature that have been used for occlusal analysis have been described. 13owever, more work is needed in this field by developing new devices or improving them to ensure accurate diagnostic methods that minimize the possibility of error. 14ualitative analysis devices are used for clinical detection at the location of the contact point in its exact position 15 ; this type of material has the advantage of presenting a low cost and simple application, such as static occlusal devices. 16,17ith quantitative analysis devices such as digital systems dynamics, 18,19 the exact intensity has to be registered in the time of contact; however, this system does not locate the position of the contact point, as the sensor is based on standardized estimates of dental positions.However, with the new software updates 20,21 and the latest digital occlusal system, the individualization of the arcade with greater precision is possible. 22For all these reasons, it is now necessary to use the combination of both systems, qualitative and quantitative 23,24, as is the case with the role of articulation in conjunction with digital occlusal systems.
Malta et al compared the sensibility and coincidence of some studies 25 between several dispositive qualitative and quantitative studies, concluding that there are differences in the number of contacts between the three systems. 26Both studies found a lower sensitivity of the digital system T-S which can be compared to the other systems. 27,28Sensitivity is adversely affected when the sensors are used several times, while the role of articulation is realized at once. 29,30In the other systems, it was observed that the number of registered contacts increased when there was no saliva on the occlusal surfaces, while this did not seem to affect the digital occlusal system. 31,32One of the limitations of the type of device that uses sensor, 33 refers to when the thickness of the film of the device 34 is greater than it should be, the results that are obtained present older contacts of posterior teeth than in previous teeth. 35,36ong et al demonstrated that the appropriate thickness of an occlusive is that of a joint paper to detect previous and subsequent anterior and posterior contacts 37 but without altering the patient's proprioception when biting.Thus, it has to be equal to or less than 20 μm. 35A reviewed index assessed the reproducibility and usefulness of instruments that valued occlusion, 35,38 among them were both static and dynamic devices.It was observed how electromyographic records 39 could measure the activation of the jaw musculature and its position, although the cost-benefit relationship of this type of device is not clear. 40Finally, the authors concluded that none of the instruments reviewed in the different publications presented results that validated their use and reproducibility. 41,42ome authors recommend that the collection of static and dynamic occlusal data 43 did not have reliability by the operator, resulting in problems in the design study 44 and the lack of standardization.
The most common indicators of static occlusion used by dentists are role of paper articulating, 45 seda, and nylon, in clinical practice 46, which allows subjectivity at the moment of occlusal analysis, even if the mark of the indicators is considered and similarity in the variants between the digital systems (►Table 4).Variations in the mark may result in differences among observers (dentists), 47 while the clinician may remove tooth structure during an occlusal adjustment, another may not see it as convenient.The clinical judgment will depend not only on the knowledge about the occlusion of the individual himself but also on the mark that the indicator used. 48he occlusion is not static but has dynamism; consequently, it must be recorded 49 and the information obtained from the static indicators for the analysis of the occlusal contacts should be complemented with that of dynamic indicators such as digital occlusal systems. 50,51

Conclusion
Digital occlusal analysis in most interventions is more objective than traditional occlusal analysis.

Clinical Relevance
This study tries to remind professionals of the importance of occlusal analysis considering it a mandatory diagnostic means in any multidisciplinary preclinical process, determining that digital occlusal analysis limits the subjectivity of conventional occlusal analysis.
Investigators performed a systematic review of selected quantitative studies.The review was performed in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) statement.The review protocol was registered a priori, is published online in the International Prospective Register of Systematic Reviews (PROSPERO) database registration number: CRD42020146370.The PICO question was as follows: To determine the efficacy of occlusal analysis in natural dentition with joint paper and digital occlusal analysis.Population: Patients with occlusal pathologies.Intervention: Intervention of all patients with occlusal pathologies.Comparison: Comparison of occlusal analysis in natural dentition with joint paper and computerized analysis.Outcome: Observation of mandibular crane cervix after occlusal analysis.[[Observational studies]], [[case-control]], [[odds ratio]], research by keywords [[dental occlusion]], [[natural dentition]], [[Immediate Complete Anterior Guidance Development]], [[occlusal adjustment]], [[mastication]], [[ bite force]], [[premature contact]], [[occlusal balance]], [[articulating paper]]], [[spray]], [[Occlusal contacts]], [[bite strength]] using the Boolean operators AND, OR, and NOT.Scopus, EBSCO, PubMed, Medline Embase, Cochrane Library, and Web Science and alternate databases Scielo, Latindex, and Redalyc were searched.Preferred Reporting Items for Systematic Review and MetaAnaysis Protocols (PRISMA) research protocol, fluxogram that explains the sequence of information selection.

Table 1
Summary of the risk of bias according to Consolidated Standards of Reporting Trials

Table 2
Summary of the risk of bias

Table 3
Structural summary of systematic review Occlusal Analysis in Natural Dentition Velasquez et al. 619 European Journal of Dentistry Vol. 17 No.3/2023 © 2022.The Author(s).

Table 4
Occlusal indicators