Location of main occluding areas and masticatory ability in patients with reduced occlusal support.

BACKGROUND: The purpose of this study was to investigate the differences in location of the main occluding area with reduction of occlusal support and to evaluate the subsequent impairment in masticatory ability. METHODS: One hundred and two patients were recruited according to the Eichner's index, which is based on the number of occlusal support zones. Each subject was instructed to clench a piece of temporary stopping in the particular occluding area that was preferably used during mastication. The main occluding area was judged by locating the tooth on which the temporary stopping rested. Subjective masticatory ability was self-assessed by means of a questionnaire. RESULTS: Group classification depending upon the location of the main occluding area was significantly associated with the category of the Eichner's index. The level of masticatory ability was significantly associated with the category of the Eichner's index. Moreover, masticatory ability was significantly more impaired in subjects with main occluding areas at the premolar regions compared to those at the molar regions. CONCLUSIONS: The location of the main occluding area may differ under the influence of the remaining natural teeth. The location of the main occluding area and the masticatory ability are likely to be closely related.

Evaluation of filtering bleb function by thermography.

AIM: To determine whether thermography can be used to evaluate bleb function. METHODS: The surface temperatures of filtering blebs from 39 eyes of 33 post-trabeculectomy patients were measured using thermography. We introduced a new parameter: the temperature decrease in the filtering bleb (TDB) where TDB = (mean temperature of the temporal and nasal bulbar conjunctiva)-(temperature of the filtering bleb). The eyes were classified into good and poor intraocular pressure (IOP) control groups according to the patients' postoperative IOP. The morphological appearance of the filtering blebs were classified by slit-lamp images according to the Indiana Bleb Appearance Grading Scale. The differences in TDB were analysed statistically. RESULTS: Mean overall scores were as follows. The TDB were 0.54 (SD 0.20) degrees C and 0.21 (SD 0.18) degrees C for the good and poor IOP control groups, respectively. The difference between the TDB of the two IOP control groups was significant (p<0.0001), but there was no significant relationship between morphological classification and TDB. CONCLUSIONS: Thermographic measurements suggest that functional blebs have lower temperatures than non-functional blebs, and their morphological appearances are not affected by their temperature. Thermography may be useful for the evaluation of bleb function.

[Clinical results of selective laser trabeculoplasty].

PURPOSE: Selective laser trabeculoplasty (SLT) is a new laser procedure using a frequency-doubled Q-switched Nd: YAG laser (wavelength: 532 mm). The laser parameters are set to selectively target pigmented trabecular meshwork (TM) cells without coagulative damage to the TM structure or non-pigmented cells. We investigated the safety and efficacy of SLT in lowering intraocular pressure (IOP). SUBJECTS AND METHOD: Sixty-seven eyes of 67 patients with uncontrolled open angle glaucoma were treated with the Coherent Selecta 7000 (Coherent Inc., Palo Alto, CA). Nineteen of 67 patients had previously received argon laser trabeculoplasty (ALT). A total of approximately 60 non-overlapping spots were placed over 180 degrees of the TM ranging from 0.5 to 1.0 mJ per pulse. The maximum energy level at which no bubble formation was observed determined choice. RESULTS: The average preoperative IOP was 22.4 mmHg. Six months after the operation, mean IOP reduction was 4.4 mmHg, and mean outflow pressure (OP) reduction was 38.1%. One month after the operation 68.7% of patients responded to treatment with an OP reduction of at least 20% ("responders"). Transient IOP elevation of 5 mmHg or greater was seen in 25.4% of patients. The success rate at 6 months after operation was 64.6% for all patients (67 eyes) and 78.2% for the responders (46 eyes). An analysis using a Cox proportional hazard model showed that a low preoperative IOP was the significant determinant for success, and the hazard ratio for the IOP increase of 5 mmHg was 2.12. Other factors such as age, gender, past history of ALT, and goniopigment were not significantly related to success. CONCLUSION: SLT appears to be a safe and effective way to lower IOP.

[Observation of physiological change in the human ciliary body using an ultrasound biomicroscope during accommodation].

PURPOSE: To evaluate changes in the ciliary body during accommodation using an ultrasound biomicroscope (UBM). SUBJECTS AND METHODS: Eleven healthy persons, aged from 24 to 33 years, served as subjects. They were asked to lie in the supine position and to fixate a target placed on the ceiling 2 m above with the left eye. A concave lens with the power of -6 to -8 diopters was then placed before the fixating left eye. The thickness of the ciliary body in the right eye was measured by UBM in the nonaccommodative and accommodative states. FINDINGS: The anterior chamber in the right eye became significantly shallow during accommodation. The thickness of the ciliary body significantly increased during accommodation at 0.5 mm and 1.0 mm posterior to the scleral spur. It significantly decreased at 2.0 mm, 2.5 mm and 3.0 mm posterior to the scleral spur. CONCLUSION: During induced accommodation in the left eye, the anterior portion of the ciliary body in the right eye increased and the posterior portion decreased in thickness. The findings imply that the circular ciliary muscles are mainly involved in accommodation and not the longitudinal muscles.