Does increasing vertical dimension of occlusion in centric relation affect muscular activity? An electromyographic study.

OBJECTIVE: In many esthetic treatments, clinicians may consider the option to modify the maxillo mandibular position. A raise of the vertical dimension of occlusion (VDO) may help restore esthetics, increase the space for dental materials, and reduce the invasiveness of dental procedures. Traditionally, VDO increases are done by using the centric relation (CR) position. Despite a long history of use, the neuromuscular effects of different maxillo mandibular relations are not fully studied. The aim of this study was to investigate the effect of alterations of maxillo-mandibular relation from maximal intercuspal position (MIP) to a raised VDO CR position on jaw-elevator muscle activity. MATERIALS AND METHODS: Fifteen healthy individuals were asked to carry out maximal voluntary clenching (MVC) in MIP and in CR on individual splints. Electromyographic (EMG) activity of the masseter and anterior temporalis muscles was assessed in µV as the root mean square of the amplitude. Specific indexes and ratios were also computed. Data analyzed in MIP and CR were compared by paired student's t-tests. RESULTS: MVC levels were not negatively affected by a VDO increase in CR position. On the contrary masseter muscles showed a statistically significant increase (p < 0.005). No significant effect on the anterior temporalis was observed. CONCLUSION: These results suggest that no immediate negative effect on maximum voluntary clenching was induced by a VDO increase in CR position. A slight increase observed in EMG clenching levels could be explained by the increase in VDO when clenching on the splint. CLINICAL IMPLICATIONS: The results of this study support the use of CR position as a pragmatic reference position due to the absence of relevant or negative changes in neuromuscular function.

Myths surrounding vertical dimension of occlusion in restorative dentistry: A scoping review.

OBJECTIVE: This scoping review aims to clarify the concept of vertical dimension of occlusion (VDO) in prosthetic dentistry, addressing prevalent myths, and controversies regarding its clinical management and impact on the stomatognathic system. METHODS: This paper critically examines common beliefs about VDO alteration and its effects on temporomandibular disorders (TMD) through an extensive literature review and an international survey. The survey included 862 general dentists and prosthodontists and explored their approaches to altering VDO and their perceptions of the clinical implications. The literature review provided a thorough analysis of existing research on VDO modification techniques, the adaptability of the stomatognathic system, and the relationship between VDO changes and TMD. RESULTS: The survey revealed insights into dentists' perspectives on VDO, showing that while many practitioners test a new VDO due to concerns about patient adaptation, a significant majority observed that patients typically adjust well to a new VDO regardless of the technique used. The survey highlighted differing beliefs about the need for a gradual process and trial phase for VDO alteration, as well as the stability of modified VDO. Literature review suggests the stability and adaptability of VDO changes due to muscle adaptability and indicates no direct causal or curative link between VDO changes and TMD. Traditional methods for determining VDO in complete dentures may not be suitable for worn dentition, underscoring the need for tailored approaches. CONCLUSION: This paper suggests that the traditional belief in the need for a prolonged trial phase for VDO alterations may be reconsidered in light of evidence supporting the adaptability of the stomatognathic system. Moreover, it emphasizes the importance of distinguishing between methods suitable for complete dentures and those for managing cases of worn dentition. The purported link between VDO alterations and TMD is also found to lack scientific evidence, highlighting the need for individualized patient care based on current evidence and clinical judgment.

Randomised controlled trial on testing an increased vertical dimension of occlusion prior to restorative treatment of tooth wear.

BACKGROUND: Evaluation of a new vertical dimension of occlusion (VDO) in complex restorative treatments is considered a necessary step prior to placement of restorations. OBJECTIVES: This randomised controlled trial (RCT) aimed to assess the effects of using an evaluation of a VDO increase before restorative treatment in patients with moderate-to-severe tooth wear, on OHRQoL, freeway space (FWS) and interventions to restorations. METHODS: Forty-two patients with tooth wear were included and randomly allocated to either a test phase with a Removable Appliance (RA) or no test phase. Restorative treatment consisted of restoration of all teeth using composite restorations in an increased VDO. OHIP-score, freeway space (FWS) and clinical acceptability of restorations were assessed at baseline and at recall appointments (1 month and 1 year). Intervention to restoration was scored in case of material chipping or when the abutment tooth had increased sensitivity that could be linked to occlusal overloading. ANCOVA analyses, Univariate Cox regression, t-tests and descriptive analyses were performed (p < .05). RESULTS: Clinical follow-up after 1 year was completed for 41 patients. No significant effect of testing the VDO with a RA could be found on the OHIP-score (p = .14). Reduction of FWS in the RA group, compared to the control group, was significantly lower at 1 year (p = .01, 95% CI -1.09 to -0.15). No effect on early interventions to restorations was found (p = .94). CONCLUSION: This RCT showed that a removable appliance is not indicated to functionally test the increased VDO prior to restorative treatment in patients with tooth wear.

Digital jaw relation recording to evaluate a new vertical dimension of occlusion using CAD/CAM-fabricated tooth-colored splints: a case report.

Pronounced defects of the dental hard tissue can be caused by different etiologic factors. Most frequently, they are associated with changes in the vertical dimension of occlusion (VDO), which may also influence the condylar positions. These defects can lead to irreversible loss of tooth structure and have dramatic functional and esthetic consequences, often requiring complex rehabilitation. In this situation, CAD/CAM-fabricated occlusal splints made of tooth-colored polycarbonate are a proven and safe pretreatment approach in terms of esthetics and function. Rebuilding lost dental hard tissue to restore the occlusion and VDO to an adequate condylar position is a prerequisite for any sustainable and functional rehabilitation. In the future, digital systems will support this complex process, customizing it and making it simpler and more precise. The DMD-System (Ignident) provides patient-specific jaw movement data to optimize the CAD/CAM workflow. This system allows real movement patterns to be digitized and analyzed for functional and potential therapeutic purposes, integrating them into the dental and laboratory workflow. In the present case, the familiar tooth-colored CAD/CAM-fabricated occlusal splint is supplemented by digital centric jaw relation recording and individual movement data.

Assessment of cost drivers and cost variation for lumbar interbody fusion procedures using the Value Driven Outcomes database.

OBJECTIVE Efforts to examine the value of care-combining both costs and quality-are gaining importance in the current health care climate. This thrust is particularly evident in treating common spinal disease where both incidences and costs are generally high and practice patterns are variable. It is often challenging to obtain direct surgical costs for these analyses, which hinders the understanding of cost drivers and cost variation. Using a novel tool, the authors sought to understand the costs of posterior lumbar arthrodesis with interbody devices. METHODS The Value Driven Outcomes (VDO) database at the University of Utah was used to evaluate the care of patients who underwent open or minimally invasive surgery (MIS), 1- and 2-level lumbar spine fusion (Current Procedural Terminology code 22263). Patients treated from January 2012 through June 2017 were included. RESULTS A total of 276 patients (mean age 58.9 ± 12.4 years) were identified; 46.7% of patients were men. Most patients (82.2%) underwent 1-level fusion. Thirteen patients (4.7%) had major complications and 11 (4.1%) had minor complications. MIS (ß = 0.16, p = 0.002), length of stay (ß = 0.47, p = 0.0001), and number of operated levels (ß = 0.37, p = 0.0001) predicted costs in a multivariable analysis. Supplies and implants (55%) and facility cost (36%) accounted for most of the expenditure. Other costs included pharmacy (7%), laboratory (1%), and imaging (1%). CONCLUSIONS These results provide direct cost accounting for lumbar fusion procedures using the VDO database. Efforts to improve the value of lumbar surgery should focus on high cost areas, i.e., facility and supplies/implant.

Analysis of cerebrovascular aneurysm treatment cost: retrospective cohort comparison of clipping, coiling, and flow diversion.

OBJECTIVE With the continuous rise of health care costs, hospitals and health care providers must find ways to reduce costs while maintaining high-quality care. Comparing surgical and endovascular treatment of intracranial aneurysms may offer direction in reducing health care costs. The Value-Driven Outcomes (VDO) database at the University of Utah identifies cost drivers and tracks changes over time. In this study, the authors evaluate specific cost drivers for surgical clipping and endovascular management (i.e., coil embolization and flow diversion) of both ruptured and unruptured intracranial aneurysms using the VDO system. METHODS The authors retrospectively reviewed surgical and endovascular treatment of ruptured and unruptured intracranial aneurysms from July 2011 to January 2017. Total cost (as a percentage of each patient's cost to the system), subcategory costs, and potential cost drivers were evaluated and analyzed. RESULTS A total of 514 aneurysms in 469 patients were treated; 273 aneurysms were surgically clipped, 102 were repaired with coiling, and 139 were addressed with flow diverter placements. Middle cerebral artery aneurysms accounted for the largest portion of cases in the clipping group (29.7%), whereas anterior communicating artery aneurysms were most frequently involved in the coiling group (30.4%) and internal carotid artery aneurysms were the majority in the flow diverter group (63.3%). Coiling (mean total cost 0.25% ± 0.20%) had a higher cost than flow diversion (mean 0.20% ± 0.16%) and clipping (mean 0.17 ± 0.14%; p = 0.0001, 1-way ANOVA). Coiling cases cost 1.5 times as much as clipping and flow diversion costs 1.2 times as much as clipping. Facility costs were the most significant contributor to intracranial clipping costs (60.2%), followed by supplies (18.3%). Supplies were the greatest cost contributor to coiling costs (43.2%), followed by facility (40.0%); similarly, supplies were the greatest portion of costs in flow diversion (57.5%), followed by facility (28.5%). Cost differences for aneurysm location, rupture status, American Society of Anesthesiologists (ASA) grade, and discharge disposition could be identified, with variability depending on surgical procedure. A multivariate analysis showed that rupture status, surgical procedure type, ASA status, discharge disposition, and year of surgery all significantly affected cost (p < 0.0001). CONCLUSIONS Facility utilization and supplies constitute the majority of total costs in aneurysm treatment strategies, but significant variation exists depending on surgical approach, rupture status, and patient discharge disposition. Developing and implementing approaches and protocols to improve resource utilization are important in reducing costs while maintaining high-quality patient care.

Increasing Vertical Dimension of Occlusion (VDO): Review.

The need to increase the Vertical Dimension of Occlusion (VDO) to restore lost dental function or optimise specific dental treatments is a common occurrence in daily dental practice. The common belief that the Vertical Dimension at Rest (VDR) is fixed hinders the development of restorations with a VDO that encroaches on or surpasses the interocclusal rest space (IRS), thereby preventing potential tissue damage to the masticatory apparatus. Recent studies have shown that the mandible rest position falls within a range termed as the "comfort zone". The range of this zone may vary from one person to another and within the same person over time due to factors such as age or health status. In this review, we have concluded that a permanent increase in the VDO, once indicated, is a safe procedure for dentulous patients. However, it is important to minimise the extent of the increase to simplify the prosthodontics treatment process. An inter-incisal increase exceeding 5 mm is seldom needed. Moreover, it is important to consider the functional, aesthetic, and biological elements associated with VDO. The biological and functional environment closely related to the VDO had great adaptive capacities, which have for a historically been underestimated. Patient adaptation has been observed in dentate patients, edentulous patients, and even cases involving implant-supported prostheses. Muscle relaxation and changes in muscle length are likely the primary adaptation mechanisms, rather than the restoration of the original VDO through dentoalveolar maturation. Intervention with a fixed restoration is more predictable and results in a higher and more rapid level of adaptation. Finally, the increase should include the entire arch to prevent relapse of the VDO to its previous value, and changes in VDO should be assessed by utilising temporary diagnostic restorations for a period before implementing definitive prostheses, in order to evaluate the adaptive muscle response.

An Aesthetic and Economic Approach of Smile Designing for a Patient With Dentinogenesis Imperfecta: A Rare Case Entity.

This is a case report presenting a female patient in her twenties suffering from severely stained, unaesthetic, and worn-out teeth since her childhood. It was a major aesthetic and functional concern for her. This clinical presentation describes the prosthetic rehabilitation of a patient with generalized discolored and worn-out teeth to have enhanced aesthetics and masticatory function of the patient. This is a referred case of dentinogenesis imperfecta- II (DGI-II) from the Department of Oral Medicine and Radiology and Oral Pathology, as diagnosed by them after a thorough clinical, radiographical, and histopathological examination. DGI is a disorder of teeth characterized by discoloration and rapid wear and belongs to a group of disorders of the development of teeth. Due to the rapid wear and generalized intrinsically stained and discolored teeth, there is a loss of vertical dimension of occlusion (VDO) and an unesthetic look of the patient respectively. Therefore, the main objective of the case report is to re-establish the aesthetic and regain the VDO and functionality of the damaged teeth using the Pankey Mann Schuyler philosophy in which the first anterior teeth were rehabilitated with porcelain fused to metal (PFM) crowns based on aesthetics and phonetics of the patient. This was followed by posterior PFM crowns based on Broadrick's flag analysis for posterior occlusal plane determination and centric occlusion.

Occlusal splints-types and effectiveness in temporomandibular disorder management.

Background: Occlusal splints are routinely used in dental offices to diagnose and treat abnormalities of the masticatory system. There are different occlusal splints, each of which can address various conditions. They may treat individuals with temporomandibular disorders (TMDs) and bruxism or be used for occlusal stabilization and dentition wear reduction. Methods: The literature in the National Library of Medicine's Medline Database was reviewed using the Mesh terms 'occlusal splints' AND 'Temporomandibular Disorders. Conclusion: Occlusal splints can treat a wide variety of TMDs. They can treat bruxism, headaches, postural imbalances related to TMDs, and decreased vertical dimension of occlusion (VDO). However, there is no clear evidence that occlusal splints are superior to physiotherapy in treating TMDs. In the long-term follow-up, they were equally effective as other therapies.

Cost analysis of primary single-level lumbar discectomies using the Value Driven Outcomes database in a large academic center.

BACKGROUND CONTEXT: Improving value is an established point of emphasis to reduce the rapidly rising health care costs in the United States. Back pain is a major driver of costs with a substantial fraction caused by lumbar radiculopathy. The most common surgical treatment for lumbar radiculopathy is microdiscectomy. Research is sparse regarding variables driving cost in microdiscectomies and often limited by cost data derived from payer-based Medicare data. PURPOSE: To identify targets for cost reduction by determining variables associated with significant cost variation in microdiscectomies, using cost data derived from the Value Driven Outcomes tool and actual system costs. STUDY DESIGN: Single-center, retrospective study of prospectively collected registry data. PATIENT SAMPLE: Six hundred twenty-two patients identified by CPT code and manually screened for initial, unilateral, single-level lumbar discectomy performed between 2014 and 2018 at a single institution. OUTCOME MEASURES: Primary outcome measures include total direct cost, clinical length of stay, and OR minutes. Total Direct Cost was further differentiated into facility and nonfacility costs. METHODS: Univariate and multivariate generalized linear models (GLM) were used to identify variables associated with variation in primary outcome measures. Costs were normalized by mean cost for patients with normal body mass index (BMI) and a healthy American Society of Anesthesiologists (ASA) classification. Average marginal effects were reported as percentage of normalized costs. RESULTS: Advanced age, male gender, Hispanic, black, unemployment, obesity, higher ASA class, insurance status, and being retired were positively associated with costs in univariate analysis. Asian, Native American, outpatient procedures, and being a student were associated with decreases in costs. In multivariate analysis, we found that obesity led to higher average marginal total direct (9%), total facility (15%), and facility OR costs (22%), as well as 24 more OR minutes per surgery. While being overweight was not associated with greater total direct costs, it was associated with higher total facility (8%), and facility OR costs (12%), with 11 more OR minutes per surgery. Age was associated with a longer LOS but not with OR costs. As expected, outpatient surgical costs, LOS, and OR time were significantly lower than inpatient procedures. Severe systematic disease was associated with greater total and nonfacility costs. In addition, Medicare patients had higher facility costs (14%) compared to privately insured patients. CONCLUSIONS: Significant drivers of total direct cost in multivariate GLM analysis were obesity, severe systemic disease and inpatient surgery. Average LOS was increased due to age and inpatient status, conversely it was decreased by unemployment and retirement. Significant variables in OR time were male sex, Hispanic race and both obese and overweight BMIs.

Cost Analysis of Inpatient Rehabilitation after Spinal Injury: A Retrospective Cohort Analysis.

Objective The lifetime direct and indirect costs of spinal injury and spinal cord injury (SCI) increase as the severity of injury worsens. Despite the potential for substantial improvement in function with acute rehabilitation, the factors affecting its cost have not yet been evaluated. We used a proprietary hospital database to evaluate the direct costs of rehabilitation after spine injury. Methods A single-center, retrospective cohort cost analysis of patients with acute, traumatic spine injury treated at a tertiary facility from 2011 to 2017 was performed. Results In the 190 patients (mean age 46.1 ± 18.6 years, 76.3% males) identified, American Spinal Injury Association impairment scores on admission were 32.1% A, 14.7% B, 14.7% C, 33.2% D, and 1.1% E. Surgical treatment was performed in 179 (94.2%) cases. Most injuries were in the cervical spine (53.2%). A mean improvement of Functional Impairment Score of 30.7 ± 16.2 was seen after acute rehabilitation. Costs for care comprised facility (86.5%), pharmacy (9.2%), supplies (2.0%), laboratory (1.5%), and imaging (0.8%) categories. Injury level, injury severity, and prior inpatient surgical treatment did not affect the cost of rehabilitation. Higher injury severity (p = 0.0001, one-way ANOVA) and spinal level of injury (p = 0.001, one-way ANOVA) were associated with higher length of rehabilitation stay in univariate analysis. However, length of rehabilitation stay was the strongest independent predictor of higher-than-median cost (risk ratio = 1.56, 95% CI 1.21-2.0, p = 0.001) after adjusting for other factors. Conclusions Spine injury has a high upfront cost of care, with greater need for rehabilitation substantially affecting cost. Improving the efficacy of rehabilitation to reduce length of stay may be effective in reducing cost.

Analysis of an overlapping surgery policy change on costs in a high-volume neurosurgical department.

OBJECTIVE: Overlapping surgery remains a controversial topic in the medical community. Although numerous studies have examined the safety profile of overlapping operations, there are few data on its financial impact. The authors assessed direct hospital costs associated with neurosurgical operations during periods before and after a more stringent overlapping surgery policy was implemented. METHODS: The authors retrospectively reviewed the records of nonemergency neurosurgical operations that took place during the periods from June 1, 2014, to October 31, 2014 (pre-policy change), and from June 1, 2016, to October 31, 2016 (post-policy change), by any of the 4 senior neurosurgeons authorized to perform overlapping cases during both periods. Cost data as well as demographic, surgical, and hospitalization-related variables were obtained from an institutional tool, the Value-Driven Outcomes database. RESULTS: A total of 625 hospitalizations met inclusion criteria for cost analysis; of these, 362 occurred prior to the policy change and 263 occurred after the change. All costs were reported as a proportion of the average total hospitalization cost for the entire cohort. There was no significant difference in mean total hospital costs between the prechange and postchange period (0.994 ± 1.237 vs 1.009 ± 0.994, p = 0.873). On multivariate linear regression analysis, neither the policy change (p = 0.582) nor the use of overlapping surgery (p = 0.273) was significantly associated with higher total hospital costs. CONCLUSIONS: A more restrictive overlapping surgery policy was not associated with a reduction in the direct costs of hospitalization for neurosurgical procedures.

Assessment of costs in open surgery and stereotactic radiosurgery for vestibular schwannomas.

OBJECTIVE: Microsurgical resection and radiosurgery remain the most widely used interventions in the treatment of vestibular schwannomas. There is a growing demand for cost-effectiveness analyses to evaluate these two treatment modalities and delineate the factors that drive their total costs. Here, the authors evaluated specific cost drivers for microsurgical and radiosurgical management of vestibular schwannoma by using the Value Driven Outcomes system available at the University of Utah. METHODS: The authors retrospectively reviewed all cases involving microsurgical and radiosurgical treatment of vestibular schwannomas at their institution between November 2011 and September 2017. Patient and tumor characteristics, subcategory costs, and potential cost drivers were analyzed. RESULTS: The authors identified 163 vestibular schwannoma cases, including 116 managed microsurgically and 47 addressed with stereotactic radiosurgery (SRS). There were significant differences between the two groups in age, tumor size, and preoperative Koos grade (p < 0.05), suggesting that indications for treatment were markedly different. Length of stay (LOS) and length of follow-up were also significantly different. Facility costs were the most significant contributor to both microsurgical and SRS groups (58.3% and 99.4%, respectively); however, physician professional fees were not specifically analyzed. As expected, microsurgical treatment resulted in an average 4-fold greater overall cost of treatment than for SRS cases (p < 0.05), and there was a greater variation in costs for open cases as well. Costs remained stable over time for both open resection and SRS. Multivariable analysis showed that LOS (ß = 0.7, p = 0.0001), discharge disposition (ß = 0.2, p = 0.004), nonserviceable hearing (ß = 0.1, p = 0.02), and complications (ß = 0.2, p = 0.005) affected cost for open surgery, whereas no specifically examined factor could be identified as driving costs for SRS. CONCLUSIONS: This analysis identified the fact that facility utilization constitutes the majority of total costs for both microsurgery and SRS treatment modalities of vestibular schwannomas. LOS, discharge disposition, nonserviceable hearing, and complications contributed significantly to the total costs for the microsurgical group, whereas none of the factors could be identified as driving total costs for the SRS group. This information may be used to establish policies and protocols to reduce facility costs, with the goal of decreasing the total costs without jeopardizing patient care.

Esthetic and function rehabilitation of severely worn dentition with prosthetic-restorative approach and VDO increase. Case report.

OBJECTIVE: The aim of this study is to report a case of restorative treatment of severely worn dentition. In this case report, the erosive/abrasive worn dentition have been reconstructed with metal ceramic crown on the posterior teeth and with ceramic veneers on the anterior teeth 1.3 - 2.3 and 3.4 - 4.3. METHODS: A prosthetic treatment was proposed to a male patient of 58 years old having a clinically significant tooth wear. After clinical exam, impressions of maxillary and mandible arches were taken with alginate to obtain preliminary casts for diagnostic waxing to all maxillary and mandibular teeth and fabrication of all provisional crowns in acrylic resin for posterior teeth, and from the diagnostic wax-up were fabricated a silicone guide masks for anterior teeth. An increase in VDO should be determined on the basis of a need to accomplish satisfactory and aesthetically pleasing restorations; it was proposed to increase the incisal lenght of the maxillary anterior incisors, together with alteration of the VDO 3 mm anteriorly. The posterior teeth 1.6 - 1.5 - 1.4 - 2.4 - 2.6 - 3.5 - 3.6 - 3.7 - 4.4 - 4.7, where the amount of tissue lost was greater, were recontructed with metal ceramic crowns. Two implants (Nobel replace 4.3x10) was placed. The implant were located in the area 4.5 - 4.6. The anterior teeth were restored with veneers. DISCUSSION AND RESULTS: The prosthetic challenge with restoring severely worn dentitions is to preserve as much of the already diminished tooth structure as possible for retention while also providing enough interocclusal space for the restorative material.

Full-arch maxillary rehabilitation fixed on 6 implants.

OBJECTIVE: The purpose of this study is to report a case of full-arch rehabilitation on six endosseous implants loaded following the standard procedure. METHODS: An implant-prosthetic treatment was proposed to a 53-year-old woman with a total prosthesis in the upper jaw. Six implants on upper maxillary were placed keeping the upper complete denture during the osseointegration period. The implants were left submerged to allow the patient to wear removable prostheses and the prosthesis was rebase with Hydrocast to not compress the sites of healing during the osseointegration period. The impression of implants was made with silicones for addition (VPS) with different viscosities after 8 weeks. The final restoration was carried out taking into account the aesthetic and functional canons. CONCLUSIONS: Correct diagnosis and accurate implant planning are key for success in implant rehabilitation.

Prosthetic-restorative approach for the restoration of tooth wear. Vdo increase, rehabilitation of anatomy and function and aesthetic restoration of anterior teeth. Case report.

UNLABELLED: Prosthetic-restorative approach for the restoration of tooth wear. Case report OBJECTIVE: This article presents a case report of combined prosthetic-adhesive rehabilitation in a patient with a generalized tooth wear. METHODS: A combined treatment adhesive - prosthetic was proposed to a male patient of 65 years old having a clinically significant tooth wear, with dentine exposure and with a reduction in clinical crown height. The erosive/abrasive worn dentition have been reconstructed with direct resin composite restorations on the posterior teeth and with zirconia crown on the anterior teeth. RESULTS: Direct composite restorations have a number of distinct advantages. These restorations have proved durable and aesthetic, protect tooth structure and posterior occlusal contact is predictably re-established. CONCLUSIONS.: A combinations of direct and indirect restorations, based on the new vertical dimension of occlusion (VDO), can help to reestablish anatomy and function.