A total of 60 freshly extracted human molars free of caries, crack and decalcification were used in this study. Charisma composite resin restoration was used. Three different lutting cement were utilized, Vitrabond, Ketac bond, and composite resin cement. Class V cavities for inlay preparation were prepared on the buccal surface of all teeth, and they were classified into two groups, 30 each.

In the first group, the composite resin inlay was cemented without heat treatment using the three types of lutting cement, 10 each. While in the second group, the composite resin inlay was heat treated before cementation for 10 ms. at 125°C. Basic fuchsin die was used to evaluate the marginal leakage after thermocycling the specimens between 50°C and 55°C. The results of this study revealed that heat curing of the inlay, as a secondary curing, significantly decrease the marginal leakage when compared with the non-heated groups. The use of composite resin cement significantly eliminate the marginal leakage when compared with the other lutting cements.
Saudi Dental Journal 1994;6(SI)-Abstr.036:p39

Although the pathological conditions that affect the temporomandibular joint are the same as those which affect other joints of the body, the unusual anatomical and functional characteristics of this structure often lead to unique clinical manifestations and growth disturbances that are not seen when these conditions occur in other areas. Added to this already complex situation is the frequent occurrence of secondary pathological alterations in the TMJ. Resulting from psychophysiological generated changes in the associated masticatory muscles. Thus, the dental practitioner is faced with a variety of conditions of diverse aetiology, often producing quite similar signs and symptoms, that are not only difficult to diagnose but also difficult to treat.

Clinical study on (500) patients complaining of TMJ problems was performed. The most common clinical features found are: pain-clicking-locking, and the pain is severe between the age 40 - 65 years, while the pain is more severe between the age 15 - 25 years. While the female-male ratio is 80% female and 20% male.

Emotional stress and bruxism are the most important aetiology in addition to other factors. This presentation will talk about the treatment applied on those patients.
Saudi Dental Journal 1994;6(SI)-Abstr.037:p40

The main objectives in the treatment of temporomandibular joint ankylosis are to restore function, improve aesthetic appearance and prevent a recurrence. But the multiplicity and great diversity of the methods used in the treatment of this disease indicate that no method is entirely satisfactory as to be unanimously accepted. Therefore, the problem still remains unresolved. Even today, opinions differ on whether interposition of some material between the resected bony surfaces is needed for permanent release of the ankylosis.

There are basically two main schools of thought in the achievement of these objectives: the interpositional and the gap arthroplasty.

Interpositional arthroplasty carries with it various complications, and does not by itself ensure success.

Following successful gap arthroplasty, the mandible continues to grow. There are no known adverse effects. In both interpositional and gap arthroplasty, it is essential that a rigorous regimen of postsurgical physical therapy be employed.

The masticatory musculature adapts functionally to the limited mouth-opening, and it has to be stretched afterwards. Therefore, the most pressing problem in the management of temporomandibular joint ankylosis is the patient's unwillingness to undertake long-term, frequent and usually painful mandibular movement exercises. Immediate postoperative mandibular movement disrupts subsequent bone bridging process and stretches the muscles and maturing fibrous tissues.

Our many years of experience in gap arthroplasty, combined with vigorous physical therapy, is illustrated with some clinical cases.
Saudi Dental Journal 1994;6(SI)-Abstr.038:p41

  039. Temporomandibular dysfunction and occlusal splint therapy

Epidemiological studies have detected a high prevalence of TM dysfunction in various populations studied. The general population is also becoming increasingly aware of the existence of this condition.

It is widely accepted that stress and occlusal interferences are implicated in the etiology. The degree to which each of these is involved varies greatly between patients, as does the individual's capacity to adapt to occlusal interferences.

Diagnosis of TM dysfunction is based upon a detailed history and clinical examination of the muscles of mastication and joints. Signs and symptoms include pain, headaches, joint noises, and restriction or deviation of movement, arising predominantly from muscle spasm.

Occlusal splint therapy is advocated as the means of choice for managing these patients. Its effect is completely reversible, and establishes what role occlusion plays in a particular case. Fabrication of a splint by two methods is discussed, as is the careful adjustment of occlusion on the appliance. The patient is closely monitored until the mandible reaches a stable position coincident with relief of muscle spasm. An assessment is then made of the occlusal discrepancy between maxillary and mandibular teeth with a view to correcting this permanently.
Saudi Dental Journal 1994;6(SI)-Abstr.039:p42

Corrected lateral tomography was developed by Rosenberg and Yale in 1965. In this technique, lateral "sagittal" tomographic images of the TMJ can be produced by compensating for the condylar horizontal and vertical angulation. The present study was undertaken to examine the variation of both the horizontal and vertical condylar angulation in a large group of patients, and also to examine the effect of incorrect compensation of these angles on the diagnostic quality of corrected lateral tomographs. The statistical analysis of the horizontal and vertical condylar angles in 1143 patients included in this study is summarized in the following table:

This table shows clearly the wide range for both the horizontal and vertical condylar angulations. It also shows that the expected value of the horizontal angulation in 95% of cases fall between 23.7 and 25.9 degrees contrary to the standard 200 horizontal angle proposed by Stansen and Baker in 1976. To demonstrate the effect of improper correction of the horizontal and vertical angulations on the image quality, a dry skull, with a prominent osteophyte on the anterior aspect of the right condyle, was used in this study. Both horizontal and vertical angulations were measured according to the technique reported by Rosenberg and Graczyk in 1986. Corrected lateral tomograms were taken for the

TMJ by compensating for the correct angles and also for angles varied ±2, £14 degrees from these angles. It was found that improper compensation for the actual horizontal or vertical angles by as low as ±2 degrees would alter the size, shape and location of the osteophyte on the corrected lateral tomograms. These results indicate the importance of individual compensation for the horizontal and vertical condylar angulation for proper tomographic imaging of the TMJ.
Saudi Dental Journal 1994;6(SI)-Abstr.040:p43-44