A New Hybrid Technique for Beading and Boxing of Complete Denture Final Impressions

Technical Note A New Hybrid Technique for Beading and Boxing of Complete Denture Final Impressions Poonam R. Kulkarni1, Rahul S. Kulkarni2, Sumeet Jain3 1 Assistant Professor, Department of Prosthodontics, Sri Aurobindo College of Dentistry, Indore, India 2 Assistant Professor, Department of Prosthodontics, Index Institute of Dental Sciences, Indore, India 3 Professor, Department of Prosthodontics, Sri Aurobindo College of Dentistry and PG Institute, Indore, India Received 27 March 2017 and Accepted 17 May 2017 Abstract Introduction: The purpose of beading & boxing of an impression is to obtain an accurate cast with proper border & base thickness for fabrication of restorations. Beading is the protection of the formed border thickness of the final impressions & Boxing of an impression is building up vertical walls around it. Aim: The purpose of this hybrid technique of beading and boxing is to produce a smooth & aesthetically acceptable cast with accurate border thickness using a simple procedure. Materials & Methods: In this hybrid technique of beading and boxing an impression, a uniform layer of modeling wax was applied over the beading of a plaster-pumice mixture around an impression; after that, boxing & pouring of an impression was done to retrieve a cast. Results: Casts obtained by hybrid technique was more accurate in border thickness & more aesthetic in comparison to the cast obtained by wax technique of beading & boxing. Conclusion: Beading and boxing of an impression is done to protect the formed border thickness of an impression, regulate the height & size of the cast, avoid undue trimming of the cast and to eliminate distortion associated with slumping of the gypsum material when an impression is inverted. This hybrid technique of beading and boxing eliminates the need for applying separating media over the beading of a plaster-pumice mixture and by this technique retrieval of the cast from the impression is very easy and quick. The resulted cast will be very neat and clean with accurate thickness of the borders and base of the cast .This technique is suitable for impressions made from almost any type of impression material. Kulkarni et al. Keywords: Mandibular Impression, Dental plaster, Pumice powder, Modeling wax, Final accurate cast. . ------------------------------------------------------Kulkarni PR, Kulkarni RS, Jain S. A new hybrid technique for beading and boxing of complete denture final impressions. J Dent Mater Tech 2017; 6(3): 103-7. JDMT, Volume 6, Number 3, September 2017 103 Introduction Beading means to protect the formed border thickness of final impressions for a dental prosthesis done by placement of a wax stick or a plaster-pumice combination or any other material adjacent to the borders prior to forming master casts. Boxing of an impression means to build up vertical walls around an impression, usually in wax, to produce the desired size and form of the base of the cast and to preserve certain landmarks of the impression (1). Success of almost every restoration in prosthodontics, except for those procedures performed directly in the mouth, depends upon accuracy of an artificial stone cast, f in terms of both dimensions & contours. An accurate diagnosis, thorough treatment planning and correct execution of mouth preparation, impression, surveying, designing and work authorization are of little value if the cast is made in a slipshod manner. There is a straight connection between the patient’s mouth and the restoration to be fabricated on the laboratory cast. Petite difficulties may be experienced by most of laboratory technicians in making a restoration that fits the master cast. Accurate fitting of the restoration to the patient’s mouth can become a problem for the dentist; however, accurate casts can reduce it to a bare minimum. The advantages of beading and boxing of an impression, subsequently manifested in the cast are: controlled dimensions and accuracy of the cast, preserved impression borders, possibility of using mounting plates, prevention of material wastage, cleaner and neater procedures, less trimming of casts needed and controlled strength and bulk (2). As per literature review, different authors have tried different techniques at different times. Bolouri, Hilger, and Gowrylok adapted modeling clay or plasticine over the plaster base for the boxing of an impression (3). Grove and Broering used a mix of 50% cornstarch and 50% solvite and poured the mixture into the boxing wax form providing a margin of at least 6 mm in every direction around the borders for the boxing of an impression (4).Rudd, Morrow and Feldmann described wax, plaster-pumice and caulking compound and paddle techniques of boxing of an impression (1). Powter and Hope method described the use of a denture flask as a boxing border for an impression instead of beading and sheet wax (5). Mullick utilized polyether interocclusal registration material with the help of adhesives instead of utility wax to form a border prior to boxing an impression of polyether or vinyl polysiloxane impression materials (6). Broner, Soni and Goldstein proposed a modified boxing technique for mandibular impressions. In this technique, a sheet of baseplate wax sectioned to three 104 JDMT, Volume 6, Number 3, September 2017 triangles was used for beading the lingual portion of an impression to achieve a recessed tongue space for greater visibility of the lingual artificial teeth arrangement (7). MacPherson and Javid used wall cleaner dough for boxing of an impression (8). Mora and Boone proposed the use of glass slab, hard plastic sheet, soft modeling dough and boxing wax for rapid boxing of impressions (9). Tautin used heavy body irreversible hydrocolloid and Ash metal strip for beading and boxing of an impression (10). Axinn and Taylor used an adjustable and reusable polyvinylchloride ring with 50% cornstarch and 50% plaster mixture for boxing of impressions (11). Stipho used irreversible hydrocolloid and boxing wax sheet for beading and boxing of impressions (12). Ritchie, Guerra and Finger proposed use of plastic or wax coated paper denture cup with irreversible hydrocolloid and a strip of rope wax for boxing complete denture impressions (13). Ansari used preformed thermoplastic box for rapid boxing of complete denture elastomeric impressions (14). Clear and Hansen proposed use of irreversible hydrocolloid and magnetic boxing strip for boxing elastomeric impressions (15). Vyas, Maru, Bali, et al described using commercially available instant adhesives around the borders to act as a joining agent between elastomeric impressions and beading wax or beads made up of base plate wax for beading and boxing of an elastic impression (16). Each technique has its pros and cons; to overcome the drawbacks, other techniques have been tried to facilitate retrieval of accurate casts. This article describes the advantages of the hybrid technique of beading and boxing of an impression ove (...truncated)