Interrelationship between implant and orthognathic surgery for the rehabilitation of edentulous cleft palate patients: a case report

A 43-year-old woman with a unilateral cleft lip and palate, presenting a totally edentulous maxilla and mandible with marked maxillomandibular discrepancy, attended the Prosthodontics section of the Hospital for Rehabilitation of Craniofacial Anomalies, University of São Paulo for treatment. She could not close her mouth and was dissatisfied with her complete dentures. Treatment planning comprised placement of six implants in the maxilla, four in the mandible followed by prostheses installation and orthognathic surgery. The mandibular full arch prosthesis guided the occlusion for orthognathic positioning of the maxilla. The maxillary complete prosthesis was designed to assist the orthognathic surgery with a provisional prosthesis (no metal framework), allowing reverse treatment planning. Maxillary and mandibular realignment was performed. Three months later, a relapse in the position of the maxilla was observed, which was offset with a new maxillary prosthesis. This isa complex interdisciplinary treatment and two-year follow-up is presented and discussed. It should be considered that this type of treatment could also be applied in non-cleft patients

Impact of removable partial denture prosthesis on chewing efficiency

Removable partial denture prostheses are still being used for anatomic, medical and economic reasons. However, the impact on chewing parameters is poorly described. OBJECTIVES: The objective of this study was to estimate the impact of removable partial denture prosthesis on masticatory parameters. MATERIAL AND METHODS: Nineteen removable partial denture prosthesis (RPDP) wearers participated in the study. Among them, 10 subjects were Kennedy Class III partially edentulous and 9 with posterior edentulism (Class I). All presented a complete and full dentate opposing arch. The subjects chewed samples of carrots and peanuts with and without their prosthesis. The granulometry of the expectorated boluses from carrot and peanuts was characterized by median particle size (D50), determined at the natural point of swallowing. Number of chewing cycles (CC), chewing time (CT) and chewing frequency (CF=CC/CT) were video recorded. RESULTS: With RPDP, the mean D50 values for carrot and peanuts were lower [Repeated Model Procedures (RMP), F=15, p<0.001] regardless of the type of Kennedy Class. For each food, mean CC, CT and CF values recorded decreased (RMP, F=18, F=9, and F=20 respectively, p<0.01). With or without RPD, the boluses' granulometry values were above the masticatory normative index (MNI) determined as 4,000 µm. CONCLUSION: RPDP rehabilitation improves the ability to reduce the bolus particle size, but does not reestablish fully the masticatory function. CLINICAL RELEVANCE: This study encourages the clinical improvement of oral rehabilitation procedure

Tongue-mandible coupling movements during saliva swallowing

International audienc

Is the tongue position influenced by the palatal vault dimensions?

International audienc

Substantiation of an artificial saliva formulated for use in a masticatory apparatus.

The aim of this work was to substantiate artificial saliva prepared for use in a masticator apparatus. Mastication's goal is to produce a viscous and plastic food bolus where these properties authorize a safe swallow. Apart from its biochemical contribution, saliva is mainly used in this kind of apparatus to provide a viscous component to the bolus. Artificial saliva was prepared with water and minerals, and completed with mucin and amylase. Different physico-chemical conditions were applied and the resultant viscosity was compared to that of human saliva. Mechanically- or chemically-stimulated salivas of ten healthy subjects were collected. Viscosity was measured with a capillary viscometer in response to changes in measurement's temperature, air exposure or pH. The effects of circadian saliva collection and the stimulation type on viscosity of human saliva were also studied. Viscosity of artificial and human salivas was comparable. An increase in the measurement's temperature or a 30 min-exposure of saliva to air led to a significant decrease in viscosity of both types of saliva. Amylase in artificial saliva did not change viscosity. The viscosity of human saliva displayed important subject variability as well as a dependence on the stimulation type of saliva production. This work allowed a useful evaluation of the formulated artificial saliva. It exhibited similar viscosity as the natural saliva in response to different methodological conditions. Therefore the proposed artificial saliva satisfies the major requirement of viscosity for a use in the masticator apparatus designed to prepare a food bolus

Douleur dentaire chez l’enfant : les parents sont-ils de bons evaluateurs? Etude preliminaire.

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The Masticatory Normative Indicator

ANR (SensInMouth, ANR 07-PNRA-O14), IFN "Prix Bernard Beaufrere 2006", and Conseil Regional d'Auvergne supported this study. Drs. P. I. N'Gom and R. Ryan helped in manuscript writing and language editingThere is no established quantitative, objective method to differentiate individuals with good masticatory function from those lacking this attribute. The aim of this study was to specify a normal range of median particle size values for masticated raw carrots collected just before being swallowed. The masticatory normative indicator (MNI) value thus obtained was based on seven studies carried out by different investigators using different methods for measuring particle size in carrot boluses. A simple mathematical transformation of variables and the choice of an interval of +/- 1.96 times the standard deviation gave 4.0 mm as the upper limit of normal median particle size for carrots in a population of young persons with good oral health. This value identifies boluses that may be considered as resulting from impaired mastication, as illustrated in healthy individuals with experimentally hampered mastication, denture wearers, and individuals presenting with obesity or Down syndrome

Development and validation of a mastication simulator

More and more research are being done on food bolus formation during mastication. However, the process of bolus formation in the mouth is difficult to observe. A mastication simulator, the Artificial Masticatory Advanced Machine (AM2) was developed to overcome this difficulty and is described here. Different variables can be set such as the number of masticatory cycles, the amplitude of the mechanical movements simulating the vertical and lateral movements of the human lower jaw, the masticatory force, the temperature of the mastication chamber and the injection and the composition of saliva. The median sizes of the particles collected from the food boluses made by the AM2 were compared with those of human boluses obtained with peanuts and carrots as test foods. Our results showed that AM2 mimicked human masticatory behavior, producing a food bolus with similar granulometric characteristics