To date, there is no consensus about the definition and diagnostic grading of bruxism. A written consensus discussion was held among an international group of bruxism experts as to formulate a definition of bruxism and to suggest a grading system for its operationalisation. The expert group defined bruxism as a repetitive jaw-muscle activity characterised by clenching or grinding of the teeth and/or by bracing or thrusting of the mandible. Bruxism has two distinct circadian manifestations: it can occur during sleep (indicated as sleep bruxism) or during wakefulness (indicated as awake bruxism). For the operationalisation of this definition, the expert group proposes a diagnostic grading system of 'possible', 'probable' and 'definite' sleep or awake bruxism. The proposed definition and grading system are suggested for clinical and research purposes in all relevant dental and medical domains.

http://www.fippdentalearning.org/fiip/wp-content/uploads/2013/12/joor12011.pdf

Bruxism defined and graded: an international consensus

Awake bruxism is defined as the awareness of jaw clenching. Its prevalence is reported to be 20% among the adult population. Awake bruxism is mainly associated with nervous tic and reactions to stress. The physiology and pathology of awake bruxism is unknown, although stress and anxiety are considered to be risk factors. During sleep, awareness of tooth grinding (as noted by sleep partner or family members) is reported by 8% of the population. Sleep bruxism is a behaviour that was recently classified as a 'sleep-related movement disorder'. There is limited evidence to support the role of occlusal factors in the aetiology of sleep bruxism. Recent publications suggest that sleep bruxism is secondary to sleep-related micro-arousals (defined by a rise in autonomic cardiac and respiratory activity that tends to be repeated 8-14 times per hour of sleep). The putative roles of hereditary (genetic) factors and of upper airway resistance in the genesis of rhythmic masticatory muscle activity and of sleep bruxism are under investigation. Moreover, rhythmic masticatory muscle activity in sleep bruxism peaks in the minutes before rapid eye movement sleep, which suggests that some mechanism related to sleep stage transitions exerts an influence on the motor neurons that facilitate the onset of sleep bruxism. Finally, it remains to be clarified when bruxism, as a behaviour found in an otherwise healthy population, becomes a disorder, i.e. associated with consequences (e.g. tooth damage, pain and social/marital conflict) requires intervention by a clinician.

Bruxism physiology and pathology: an overview for clinicians*

Statement of problem Various implant impression techniques, such as the splint, pick-up, and transfer techniques, have been introduced, and some techniques may be more accurate than others. Also, clinically, some factors, including the angulation or depth of implants, may affect the accuracy of the implant impressions. Purpose The purposes of this review were to: (1) investigate the accuracy of published implant impression techniques, and (2) examine the clinical factors affecting implant impression accuracy. Material and methods An electronic search was performed in June 2008 of MEDLINE, EMBASE, and Cochrane Library databases with the key words implant, implants, impression, and impressions. To be included, the study had to investigate the accuracy of implant impressions and be published in an English peer-reviewed journal. In addition, a hand search was performed to enrich the results for the time period from January 1980 to May 2008. After executing the search strategies, 41 articles were selected to be included in the review process. Results All of the selected articles were in vitro studies. Of the 17 studies that compared the accuracy between the splint and nonsplint techniques, 7 advocated the splint technique, 3 advocated the nonsplint technique, and 7 reported no difference. Fourteen studies compared the accuracy of pick-up and transfer impression techniques, and 5 showed more accurate impression with the pick-up techniques, 2 with the transfer technique, and 7 showed no difference. The number of implants affected the comparison of the pick-up and splint techniques. Eleven studies compared the accuracy of polyether and vinyl polysiloxane (VPS), and 10 of 11 reported no difference between the 2 materials. Four studies examined the effect of implant angulation on the accuracy of impressions. Two studies reported higher accuracy with straight implants, while the other 2 reported there was no angulation effect. Conclusions The review of abutment level or implant level internal connection implants indicated that more studies reported greater accuracy with the splint technique than with the nonsplint technique. For situations in which there were 3 or fewer implants, most studies showed no difference between the pick-up and transfer techniques, whereas for 4 or more implants, more studies showed higher accuracy with the pick-up technique. Polyether and VPS were the recommended materials for the implant impressions. (J Prosthet Dent 2008;100:285-291)

The accuracy of implant impressions: a systematic review.

Background
The purpose of this study was to compare two impression techniques from the perspective of patient preferences and treatment comfort.

/pdf/comparison-of-digital-and-conventional-impression-techniques-25fv4h7cb3.pdf

Comparison of digital and conventional impression techniques: evaluation of patients’ perception, treatment comfort, effectiveness and clinical outcomes

Statement of problem Computer-aided technology is an emerging method for fabricating complete dentures. Consolidated information about historical background, current status, and scope for the future is lacking. Purpose The purpose of this systematic review was to analyze the existing literature on computer-aided technology for fabricating complete dentures and provide the reader with a historical background, current status, and future perspectives on this emerging technology. Material and methods An electronic search of the English language literature between the periods of January 1957 and June 2012 was performed by using PubMed/MEDLINE with the following specific search terms: CAD-CAM complete dentures, digital complete dentures, computer dentures, designed dentures, machined dentures, manufactured dentures, milled dentures, and rapid prototyping dentures. Additionally, the search terms were used on the Google search engine to identify current commercial manufacturers and their protocols. Results A total of 1584 English language titles were obtained from the electronic database, and the systematic application of exclusion criteria resulted in the identification of 8 articles pertaining to computer-aided technology for complete dentures. Since the first published report in 1994, multiple authors have described different theoretical models and protocols for fabricating complete dentures with computer-aided technology. Although no clinical trials or clinical reports were identified in the scientific literature, the Google search engine identified 2 commercial manufacturers in the United States currently fabricating complete dentures with computer-aided design and computer-aided manufacturing (CAD/CAM) technology for clinicians world-wide. These manufacturers have definitive protocols in place and offer exclusive dental materials, techniques, and laboratory support. Their protocols contrast with conventional paradigms for fabricating complete dentures and allow the fabrication of complete dentures in 2 clinical appointments. Conclusions A body of scientific literature related to computer-aided technology for complete dentures is emerging. Significant advancements in this technology have now resulted in their commercial availability with shorter clinical protocols. However, prospective clinical trials with true clinical endpoints are necessary to validate this technology. This could affect dental education, patient care, research, and public health worldwide.

Computer-aided technology for fabricating complete dentures: systematic review of historical background, current status, and future perspectives.

A Abbe flap \ăb# e flăp\ [Robert Abbe, New York, N.Y. surgeon, 18511928]: eponym for a lip switch operation. A triangular, full thickness flap from the lower lip used to fill in a deficit in the upper lip. Specifically applied to the midportion of the upper or lower lip— called also lip switch operation Abbe, R. A new plastic operation for the relief of deformity due to double harelip. Med Rec 1898;53:477. ab duct \ăb dŭkt#\ vt (1834): to draw away from the median plane— comp ADDUCT ab er rant \ă-bĕr#ant\ adj (ca. 1798)1: a deviation from the normal or usual course, form, or location 2: straying from the normal way ab frac tion \ăb frăk#shun\ n (1991): the pathologic loss of hard tooth substance caused by biomechanical loading forces. Such loss is thought to be due to flexure and chemical fatigue degradation of enamel and/or dentin at some location distant from the actual point of loading—comp ABLATION, ABRASION, ATTRITION, and EROSION ab la tion \ă-bl a#shun\ n (15c) 1: separation or detachment; extirpation; eradication 2: removal of a part, especially by cutting—see ABFRACTION, EROSION abrade \uh-br ad#\ vt (1677): to rub away the external covering or layer of a part—comp ATTRITION, EROSION abra sion \ă-br a #shun\ n (1656) 1: the wearing away of a substance or structure (such as the skin or the teeth) through some unusual or abnormal mechanical process 2: an abnormal wearing away of the tooth substance by causes other than mastication—comp ATTRITION, EROSION abra sive \uh-br a # siv, -ziv\ n (1853): a substance used for abrading, smoothing, or polishing abra sive \uh-br a # siv, -ziv\ adj (1875) 1: tending to abrade 2: causing irritation—abra sive ly adv, abra sive ness n ab ra si vity \uh-br a#siv-ı̆-t e, -ziv-ı̆-t e\ v (1998): the property of one material to wear away another material by means of frictional contact absorbed dose \ab-sôrbd#,-zôrbd# d os\: the amount of energy from ionizing radiation absorbed per unit mass of matter, expressed in Gray units ab sorp tance \ab-sôrp#tans, -zôrp#tans\ n (ca. 1931): the ratio of the radiant energy absorbed by a body to that incident upon it ab sorp tion \ab-sôrp#shun, -zôrp#-\ n (1741) 1: the uptake of substances into or through tissues, e.g., mucosa, skin, and intestine 2: in radiology, the uptake of energy by matter with which the radiation interacts—see A. of RADIATION—comp ADSORPTION absorption of radiation \ab-sôrp#shun ŭv r a#d ea#shun\: collisionlike interactions between the individual particulate or quantum components of a beam of radiation and the subatomic parts of matter that occur at random during irradiation. Each interaction may result in partial or complete transfer of energy abut ment \a-bŭt#ment\ n (1634) 1: that part of a structure that directly receives thrust or pressure; an anchorage2: a tooth, a portion of a tooth, or that portion of a dental implant that serves to support and/or retain a prosthesis—usage see ANGULATED A., HEALING A., DENTAL IMPLANT A., INTERMEDIATE A., ONE PIECE A., PREPARATION PIECE A., STANDARD A., TWO PIECE A. DropB

A Buj-Bello

Papers

The glossary of prosthodontic terms.