The purpose of this article is to discuss the clinical considerations related to increasing the occlusal vertical dimension (OVD) when restoring a patient's dentition. Thorough extraoral and intraoral evaluations are mandatory to assess the suitability of increasing OVD. In the literature, multiple techniques have been proposed to quantify OVD loss. However, the techniques lack consistency and reliability, which in turn affects the decision of whether to increase the OVD. Therefore, increasing OVD should be determined on the basis of the dental restorative needs and aesthetic demands. In general, a minimal increase in OVD should be applied, though a 5 mm maximum increase in OVD can be justified to provide adequate occlusal space for the restorative material and to improve anterior teeth aesthetics. The literature reflects the safety of increasing the OVD permanently, and although signs and symptoms may develop, these are usually of an interim nature. Whenever indicated, the increase in OVD should be achieved with fixed restorations rather than a removable appliance, due to the predictable patient adaptation. The exception to this is for patients with TMD, where increasing the OVD should still be achieved using removable appliances to control TMD-associated symptoms before considering any form of irreversible procedure.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1834-7819.2011.01640.x

Clinical considerations for increasing occlusal vertical dimension: a review.

Statement of problem Measuring vertical dimension is a soft-tissue measurement. Therefore, inaccuracy may occur. Purpose The purpose of this study is to compare the accuracy of the Willis gauge method with the caliper method. Material and methods The Willis gauge measures the distance between the septum of the nose and the chin. The caliper method measures the distance between reference points on the tip of the nose and the chin. Twenty predoctoral students applied both methods 10 times in measuring the rest vertical dimension (RVD) and the occlusal vertical dimension (OVD) of a single edentulous patient. The measurements obtained from one experienced clinician were selected as controls for the interocclusal distances (IOD) for the Willis and the caliper methods, respectively. One-sided t tests and a 1-sided nonparametric test were used to determine significant differences between the 2 methods (α=.05). Results The variances in the RVD values for the Willis gauge method were higher than for the caliper method for most students. A Wilcoxon signed rank test showed that the accuracy of the OVD measurements for the caliper method was significantly better than for the Willis gauge method ( P =.001). This was not the case for the RVD measurements ( P =.073).The average IOD for the Willis method was significantly higher than the control IOD ( P =.026). The average IOD for the caliper method was not significantly larger than the control ( P =.1303). Conclusion This study showed that the use of the caliper method by predoctoral students was a significantly more reliable method of measuring the OVD for the patient evaluated.

A comparison of the accuracy of two methods used by pre-doctoral students to measure vertical dimension

Determination of the occlusal vertical dimension (OVD) is an integral part of complete dentures fabrication Due to the lack of teeth, the clinician faces the challenge of how to accurately establish the OVD of the new denture Therefore, the purpose of this review article was to present, discuss and critique the available methods used in determining the OVD for complete dentures patients This review identified two main streams to determine the OVD: (i) pre-extraction methods and (ii) post-extraction methods For the pre-extraction methods, the OVD of the natural dentition is transferred to the new dentures mainly by intra-oral measurements, profile tracing and cephalometric analysis The post-extraction methods rely on mandibular rest position, facial aesthetic appearance, swallowing pattern, craniofacial landmarks measurements, cephalometric analysis, phonetics and existing dentures In general, all the available techniques have merits and are helpful for routine clinical use However, they are empirical in nature, controversial and lack the scientific support Further, there is no single accurate method for OVD determination To overcome the limitations of the techniques, the clinician will benefit from applying combination of techniques to approximate the OVD

Determination of occlusal vertical dimension for complete dentures patients: an updated review.

During an extensive prosthetic reconstruction, the choice of the vertical dimension of occlusion (VDO) is frequently presented as the main point to obtain a success of treatment. Probably, it is a sensible opinion to think that there is an optimal adaptive space concerning the vertical dimension (VD) rather than a magic point. The practitioner may play with the VD, if a strict rotation around the hinge axis is utilized, if the facial type is not worsened and if lip closure is kept in a natural position. In case of temporomandibular osteoarthritis, non progressive large changes of VD have to be avoided. The decision making will be described in relation to different factors, such as overjet, overbite, prosthetic space, mandibular morphology, profile, vertical and horizontal skeletal type. A decision-making table is proposed to visualize the trend of these different factors.

Vertical dimension of occlusion: the keys to decision

Changing the occlusal vertical dimension (OVD) has been one of the most controversial issues of restorative dentistry. The modification of the OVD may be indicated whenever it is necessary to harmonize dentofacial esthetics, provide space for planned restorations, and improve occlusal relationships. The OVD should not be considered an immutable reference, but rather a dynamic dimension within a zone of physiological tolerance that can be altered as long as the dentist respects the envelope of function. However, vertical changes in the relationship between the maxilla and mandible may have some biological, biomechanical, esthetic, and three-dimensional (3D) functional implications because the initial references of maximum intercuspation and anterior tooth relationships must be reconstructed and adjusted in a new dimension of space. This article aims to present a critical review of the relevant OVD literature and provide the clinical objectives and subjective parameters necessary to guide the clinician and laboratory technician during treatment involving OVD alterations.

Occlusal vertical dimension: treatment planning decisions and management considerations.

The literature does not establish a single proven method for determining lower facial height, which is called the Vertical Dimension of Occlusion (VDO), and the concept of a vertical comfort range is generally accepted. This study aimed to test the statistical significance of correlations of mandibular shape versus lower facial height in occlusion, using cephalometric measurements. Correlations for 505 consecutive healthy adults were calculated between angles that estimate the lower facial height and angles that estimate the mandibular shape. The mandibular angle (gonial) showed a higher coefficient of correlation (r = 0.691) than the inferior gonial angle. The dispersion remained large, i.e. r2 = 0.478. Cephalometric measurements, despite theirs imperfections, could help the practitioner to understand what the best course of treatment would be in order to obtain a lower facial height in occlusion showing a skeletal harmony with the mandibular shape.

J.-D. Orthlieb

Papers

Cephalometric estimation of vertical dimension of occlusion.