Centric relation critically revisited-What are the clinical implications?

PURPOSE OF THE ARTICLE: Centric relation is a dental term that has undergone many alterations over the years, which in turn have led to significant clinical controversies. These continuing changes in the meaning of the term CR have not only led to confusion, but they also have resulted in a variety of unnecessary diagnostic and therapeutic procedures. Analysis of the dental literature reveals ongoing misunderstanding and disagreement regarding that term among both clinicians and academic dentists. MATERIALS AND METHODS: A search of the PubMed database was performed with the following search terms: "centric relation", "masticatory muscles", "maxillomandibular relationship" and "condylar position." Relevant literature from the past 70 years until the present day was meticulously scrutinised. RESULTS: As expected, the literature review on the topic of CR revealed a problematic pattern of changing definitions and clinical disagreements, all of which have had a significant impact on the practice of dentistry. CONCLUSION: There are semantic, conceptual and practical reasons for concluding that the term 'centric relation' is flawed. Those flaws have a significant impact on dental practice. Based on our analysis, argumentation is provided to conclude that the term 'centric relation' should be abandoned. Instead, it appears that every individual has a unique temporomandibular joint relationship which cannot be described by any singular term. In healthy dentate patients, this relationship is determined by the maximum intercuspation of the teeth and should therefore be considered as biologically acceptable.

Spray and stretch technique and its effects on mouth opening.

STATEMENT OF PROBLEM: Mandibular mouth opening through passive stretching may be an awkward and painful experience for patients with orofacial pain. Whether a spray technique would reduce such discomfort is unclear. PURPOSE: The purpose of this clinical study was to determine whether the use of a spray technique would be an effective method of increasing maximal mouth opening (MMO) without passive stretching to avoid patient discomfort. MATERIAL AND METHODS: A sample of 61 participants, 33 men and 28 women, without orofacial pain was selected from a general dental office, and a sample of 60 participants, 30 men and 30 women, was selected from a cohort of over 750 patients with orofacial pain from an oral surgery department. The presence of orofacial pain in the patient group was verified and recorded by means of palpation of the temporomandibular joints (TMJs) and masticatory, neck, and shoulder muscles. All participants in the study were instructed to open their mouth maximally to permit insertion of a TMJ equilateral triangle and the measurement of their MMO twice. Then, the participants were informed that a vapocoolant would be sprayed twice on both cheeks from the mandibular angle to the temple area. After spraying, the participants were requested to open their mouth maximally, and again the interincisal distance was measured twice. For analysis of the variables, a 2-way ANOVA was used with estimates for group effects and a correction for sex. A covariance model was used to test the effect of age (α=.05). RESULTS: Testing for age revealed an effect for both study groups (P=.032), but not for sex (P=.074). Testing baseline values of maximal mouth opening for the studied groups revealed no significant difference (P=.175), although for sex, it did (P=.008). The relative gain as a percentage of increase in mouth opening led to similar results, comparable with the values of the absolute increase in magnitude (P<.001 for the study groups and P=.090 for sex). Testing the effect of age in a covariance model did not lead to a significant result (P=.73). CONCLUSIONS: The spray and stretch technique increased maximal mouth opening in most participants, more so in participants with orofacial pain than in the control group and more in women than in men. Pain from passive stretching can be prevented.

A patient's view on the location of the temporomandibular joint.

ObjectiveA survey was held to establish whether laypeople knew the location of their temporomandibular joint. MethodsA sample of 61 participants, visiting their dental office for a routine check-up, was given a three-question survey of whether they knew the location of their temporomandibular joint and could point to this location. ResultsThirty-eight participants answered the question affirmatively. Only 13 pointed to the correct location. Of these, six participants received consultation for TMD in the past, three participants were healthcare providers, and four participants actually had knowledge of the exact location. Out of 23 participants who did not know the location, one accidently designated the correct position. ConclusionThe location of the temporomandibular joint is not a well-known site for many patients. In the presence of orofacial pain, it seems advisable to let the patient designate and record the site of the pain on a drawing on the patient chart.

Specialisation and specialist education in prosthetic dentistry in Europe.

This presentation reports on the results of a meeting of prosthodontists from selected European countries. The aim of the meeting was to analyse and promote specialisation and specialist education in Prosthetic Dentistry in Europe. Representatives for Europe were selected from the European Prosthodontic Association (EPA) board, the Education and Research Committee of International College of Prosthodontists (ICP), countries with a legally recognised speciality, countries without a recognised speciality but organised training programmes and countries with neither of these situations. Data about specialisation and specialist training in Prosthodontics in Europe was scrutinised and discussed. The programmes for countries with specialist training had relatively similar content, mostly of three years duration. There was strong agreement that a recognised speciality raises the level of care within the discipline for both specialists and non-specialists. In several of the countries where a speciality had been introduced it had been initiated by pressure from public health planning authorities. The conclusions are that from a professional viewpoint an advancement of the speciality over Europe would develop the discipline, improve oral health planning and quality of patient care. A working group for harmonisation was recommended.