Periodontal disease has known etiological factors which include plaque and calculus which harbor bacteria. This multifactorial disease process is primarily a chronic inflammatory response to toxic bacterial byproducts which are the result of a lack of effective oral hygiene procedures. This is particularly true in cases of iatrogenically induced periodontal disease of the hard and soft tissue caused by restorations which violate known biological principles. Ill fitting restorations harbor plaque and calculus and frequently exhibit residual excess cement. The patient nor the clinician can accomplish effective oral hygiene which would maintain an acceptable level of gingival health. Crown preparations which violate the biologic width, are over contoured, and/or have uncleansible bridge or splint connectors cause chronic inflammation which destroys the supporting tissues. Continue reading
Occlusal corrections on multiple crowns can be a daunting task. Even with the most meticulous technique, there are times when you have to do more than “just a little” adjustment to your full mouth cases or you may just want to really detail the occlusal scheme of your masterpiece. Do you make these adjustments in the mouth on what some call the “final articulator”? I think everyone would agree that it can be difficult and sometimes impossible to make final adjustments of multiple crowns intra-orally, so how can one utilize an indirect approach to the tedious task of perfecting the occlusion? Continue reading
Some view the implant provisional as a costly and unnecessary prosthodontic procedure, but in reality, routinely providing this simple service can save costly remakes. Casual observation of the planned prosthesis may not reveal issues which could potentially cause costly esthetic and/or functional failures. Gingival contours, anatomical form, occlusal parameters, as well as restorative space availability can all be assessed prior to the fabrication of the final prosthetic tooth replacement. All of the information gleaned from this prototype can provide a roadmap for the technician in the journey to a successful outcome. If you are able to provide a successful implant provisional, then you are almost certainly assured of delivering a successful final tooth replacement. Most importantly, if your provisional isn’t esthetic, functional, and hygienic, you have the opportunity to modify your prototype until you get it right! This is the only way to experience consistent results. View these quick fabrication steps to make your chair side experience easier… Continue reading
Current literature tells us that it isn’t possible to achieve a truly “passive” framework that splints multiple implants. No matter what techniques or materials are used, there will always be some measurable stress or strain created. It is known that framework misfits can cause screw breakage as well as component fracture but it’s effect on the supporting bone is still something of a mystery. Some researchers feel that the bone can remodel in response to an ill fitting framework but the amount that can be tolerated isn’t quantifiable. Best practice procedures tell us that we should strive for frames that show no clinical or radiographic marginal opening, so it is important to review some simple ways to control clinical and laboratory generated errors. Continue reading
An implant supported prostheses requires careful planning and execution to ensure that it will give many years of service. From an engineering standpoint, nothing is more complicated in dentistry than implant prosthodontics. Material choice is paramount to the successful replacement of missing teeth. Since we don’t have a singular material that can satisfy the both the esthetic and functional demands, we must blend two or three different materials into a homogenous structure utilizing the best qualities of each to great advantage. In this case the decision was made not to place an implant in the bicuspid location for a traditional 3 unit bridge because of the lack of available bone and the proximity of the mental nerve. And so, a cantilever was created in the zirconia substructure with a tall but cleansable connector. Zirconia was chosen for the supporting structure because of its high strength (900-1200 mPa) as well as its biocompatibility. The base of the prosthesis in contact with the tissue is polished to a mirror-like finish with diamond paste. Unfortunately zirconia in it’s monolithic state exhibits poor esthetic properties. Rather than veneering the substructure with a low strength ceramic (90 mPa), the superstructure was pressed from a high translucency lithium disilicate ingot into a monolithic form. Managing the properties of light through the choice of ceramic materials gave this reconstruction lifelike properties with great strength for a long lasting prosthetic replacement for missing teeth….