Increasing occlusal vertical dimension in prosthetic rehabilitation of TMD patients

OBJECTIVES The purpose of this study is to analyze the scientific literature relating to the issue of the in-creasing occlusal vertical dimen-sion (OVD) in the prosthetic reha-bilitations of patients with tempo-ro-mandibular disorders (TMD) aimed at identifying a correct de-cision-making path in the man-agement of prosthetic treatment on the basis of the data currently available on the topic. MATERIALS AND METHODS The research was conducted us-ing the PubMed and Scopus data-bases. The inclusion criteria led to analyze all the selected material through the following key terms: "occlusal vertical dimension"; "in-creasing occlusal vertical dimen-sion"; "temporo-mandibular dis-orders"; "dental occlusion". The exclusion criteria do not allow to examine case reports, reviews and works that do not deal with the issue of increasing the vertical dimension of occlusion in the prosthetic-rehabilitation and that do not deal with issues relating to TMD, occlusion and the role of re-habilitation prosthetic. RESULTS TMDs are less related to occlusion than previously believed. Current-ly there is no scientific evidence to consider prosthetic therapy an eti-ological factor or a treatment op-tion of TMD. Prosthetic rehabilita-tion that involves increasing OVD in patients with TMD presupposes the correct diagnosis of the gnathological problem according to modern guidelines and therapy aimed at resolving the symptoms and restoring normal mandibular movements. Increasing OVD should only be used for prosthetic reasons and goals; not exceeding 5 mm can be considered a safe and predict-able procedure. The increase OVD presupposes adaptability of the stomatognathic system to the new vertical dimension. CONCLUSIONS Currently there are no guidelines supported by scientific evidence on the management of rehabilita-tions with increased OVD in TMD patients. In these cases, the pros-thetic treatment must be conduct-ed as predictably as possible, ac-cording to careful planning and based on prosthetic goals. Permanent occlusal changes in-volving an elevation of the vertical dimension should only be per-formed after the patient has demonstrated adaptability to the new vertical dimension. CLINICAL SIGNIFICANCE The key point of these cases the diagnosis of the gnathological problem which can be very complex. It is important for the dentist to evaluate the diagnosis as specific as possible. If the di-agnosis is correct, therapy and treatment will be compliant and corresponding. Working with long-term provision-al restorations and using them as a model for the definitive rehabili-tation, even if they seem to be based more on the experience of the clinician than on scientific evi-dence, is still the best option to safely manage rehabilitations with vertical dimension elevation in these patients.