Restoration of the anterior guide with the fixed prosthesis

The anterior guide is a functional entity, which is part of the set of guidance provided by the dento-dental joints to the mandibular kinematics, essential for the establishment of harmonious occlusal relations. The anterior guide is a key to understanding and reconstructing the occlusion, playing both a role of protecting the posterior teeth and guiding the functional movements of the mandible. Currently, it also represents an “exteroceptive feeler” creating a cone of access to the occlusion in intercuspation. The restoration of functional and protective anterior guidance is therefore essential for the balance of the masticatory system. This rehabilitation can only be achieved by examining and accurately diagnosing the occlusion relationships maintained by the anterior teeth, associated with a reasoned therapeutic approach validated by a test phase. After a brief description of the anterior function and its role, this article aims to detail, through a clinical case, the procedure to follow for the restoration of a functional anterior guide.

Incidence of Malocclusion among Young Patients with Gingival Recessions—A Cross-Sectional Observational Pilot Study

Background and Objectives: Dental occlusion and gingival recession have been studied over the past years especially because of the increasing incidence of occlusal interferences in young patients. The purpose of this pilot study is to investigate any association between occlusal dysfunctions and gingival recessions. Data on gingival phenotype and previous orthodontic treatment were also collected to assess any correlation with the presence of gingival recession. Materials and Methods: Forty systemically healthy subjects, without signs of periodontitis and with gingival recessions, were included in the study. The following parameters were determined: location and extent of the gingival recession, gingival phenotype and functional occlusion by means of observing and registering the occlusal contacts in maximum intercuspation position, protrusive and lateral guidance. Results: Premolars were mostly affected in cases of working-side interferences during lateral guidance (71.19% of the affected teeth during left and 75% during right mandibular movements). The chi-squared exact test applied for the analysis of contingency tables revealed statistically significant associations between excursive interferences during lateral guidance and anterior guidance and the presence of gingival recession on the involved group of teeth. Conclusions: The results suggest that most gingival recessions might be associated with working-side interferences, the highest number of gingival recessions being associated with active interferences during lateral guidance.

Full mouth rehabilitation for severely worn dentition using fixed prostheses and tooth-supported partial overdenture: a case report.

Rehabilitation of severely worn dentition represents a significant clinical challenge, especially when the restorative space is not sufficient. Creating restorations that fulfil the aesthetic, occlusal and functional parameters are essential to long-term success. This case report describes a 48-year-old male, who had severely worn dentition, which resulted in collapsed vertical dimension. The initial treatment involved careful planning, stabilization of existing dental diseases and construction of provisional prostheses at increased vertical dimension. Once the compatibility of the new vertical dimension had been confirmed, permanent reconstruction was performed. As with all full mouth prosthetic rehabilitation cases, equal-intensity centric occlusal contacts on all teeth and an anterior guidance in harmony with functional jaw movements were critically taken into account in each treatment phases.

Influence of Anterior Guidance on the Inclination of Horizontal Condylar Guidance in Dentulous Subjects - A Clinical Study

BACKGROUND One of the most widely used methods to record horizontal condylar guidance is the use of protrusive interocclusal records. Therefore, this study was done to evaluate the reliability of protrusive interocclusal record with and without the influence of anterior determinant on horizontal condylar guidance among dentulous patients. METHODS Diagnostic impressions of 21 participants were made and casts were poured. Facebow record were obtained and transferred to semi-adjustable articulator. Protrusive interocclusal records were made using Alu-wax. In group 1, protrusive interocclusal records were obtained at incisal edge to edge position (conventional method). In group 2, 3 and 4 protrusive interocclusal records were obtained at a distance of 4 mm, 6 mm and at incisal edge to edge position respectively using a customized flat anterior jig. Programming of the Hanau articulator were done for all the 4 groups. One-way ANOVA test and Pearson’s correlation tests were done to compare and correlate horizontal condylar guidance. RESULTS The mean values obtained for flat anterior jig at incisal edge to edge position, at 4 mm and 6 mm provided good Pearson correlation values for the right (R = 0.773, R = 0.779, R = 0.632) as well as the left side (R = 0.631, R = 0.601, R = 0.545) respectively, on comparison with the conventional incisal edge to edge values. This indicated a positive correlation which was statistically significant. CONCLUSIONS The horizontal condylar guidance is influenced by anterior determinant. Therefore, the reliability of protrusive records is dependent on eliminating the influence of anterior determinant. KEY WORDS Horizontal Condylar Guidance, Anterior Determinant, Protrusive Interocclusal Records

Influence of fibromucosa height and loading on the stress distribution of a total prosthesis: a finite element analysis

Purpose: To evaluate the effect of fibromucosa height on the stress distribution and displacement of mandibular total prostheses during posterior unilateral load, posterior bilateral load and anterior guidance using the finite element analysis (FEA). Material and methods: 3D virtual models were made to simulate the stress generated during different mandibular movements in a total prosthesis. The contacts were simulated according to the physiology, being considered perfectly bonded between cortical and medullar bones; and between cortical bone and mucosa. Non-linear frictional contact was used for the total prosthesis base and fibromucosa, allowing the prosthesis to slide over the tissue. The cortical bone base was fixed and the 100 N load was applied as unilateral load, posterior bilateral load and anterior guidance simulation. The required results were for maximum principal stress (MPa), microstrain (mm/mm) and total displacement (mm). The numerical results were converted into colorimetric maps and arranged according to corresponding scales. Results: The stress generated in all situations was directly proportional to the fibromucosa height. The maximum principal stress results demonstrated greater magnitude for anterior guidance, posterior unilateral and posterior bilateral, respectively. Only posterior unilateral load demonstrated an increase in bone microstrain, regardless of the fibromucosa height. Prosthesis displacement was lower under posterior bilateral loading. Conclusion: Posterior bilateral loading is indicated for total prosthesis because it allows lower prosthesis displacement, lower stress concentration at the base of the prosthesis and less bone microstrain. Keywords Finite element analysis; Occlusion; Total prosthesis.

CUSTOMISED INCISAL GUIDE TABLE FOR REHABILITATION OF MAXILLARY ANTERIOR TEETH: A CASE REPORT

Restoration of anterior guidance is a major challenge to the clinician in the planning of all restorative treatments. An accurate anterior guidance is important for proper function, aesthetics, comfort, and phonetics. Anterior guidance should be established with extreme caution while restoring anterior teeth as even a slight error in this regard can have detrimental effects on the entire stomatognathic system. This article describes the anterior rehabilitation of a 50-year-old patient who met with a road traffic accident and lost his upper anterior teeth. Anterior guidance developed in the provisional restorations was accurately recorded in the customized incisal guide table and permanent restorations were fabricated accordingly. Although the patient presented for the replacement of the fractured prosthesis, a comprehensive evaluation determined that a customized incisal guide table was needed to correct an array of dental issues. The treatment plan dramatically improved overall esthetics, comfort, and function.

The Occlusal, Neurological, and Orthopedic Origins and Implications of the Hypersensitive Dentition

In the dental literature, the association between the occlusion and hypersensitive teeth is poorly explained. Quantified occlusal contact force and timing parameters have been largely ignored in studies assessing hypersensitive teeth. This chapter introduces a novel occlusal concept, frictional dental hypersensitivity (FDH), after systemically simplifying the existing and often confusing terminology used in the literature to describe the variant clinical presentations of the hypersensitive dentition. Clinical evidence from combining computerized occlusal analysis and electromyography is presented linking opposing posterior tooth friction and muscular hyperactivity to FDH. This chapter will outline how occlusion, many muscular TMD symptoms, and FDH are all interrelated. Both a pilot study and a 100 subject cold ice water swish follow-up study are presented and used a numerical visual analog scale (NS/VAS) to quantify cold response dental hypersensitivity resolution observed in occlusally symptomatic patients that underwent the immediate complete anterior guidance development coronoplasty (ICAGD). This computer-guided occlusal adjustment procedure eliminated pretreatment FDH symptomatology, further supporting that dental hypersensitivity often has an occlusally-based, frictional etiology. Additionally, consideration for the orthopedic influences that may directly affect the occlusion and neurology of the system are outlined, as well as the medical concept of tooth allodynia. Furthermore, trigeminal neurological influences are compared and contrasted to autonomic sympathetic inputs in relation to the influence that they each have upon the hypersensitive dentition. Lastly, the greater auricular diagnostic nerve block is discussed, as is the influence that this nerve may have upon the hypersensitive mandibular posterior dentition.

Rehabilitation of Severely Attrited Teeth with Hobo Twin Stage Technique: A Case Report

Restoration of excessively worn dentition is a challenging treatment procedures. It requires effi cientdiagnosis and treatment plan. Hobo’s techniques and Pankey Mann Schuyler’s philosophy arewidely used and documented for full mouth rehabilitation. We have reported the case of a 56-year-old male patient who presented with the severely worn dentition and had diffi culty in chewing. Torehabilitate this case Hobo’s twin stage technique had been adopted as it is based on scientifi c dataand mathematical analysis for both disocclusion and anterior guidance thus reducing chair side time.