An algometer for intraoral pain tolerance measurements.

An algometer was developed to provide a variable probing force (0-200 g force) which could be used intraorally. This algometer consisted of an autoclavable probe handpiece attached to an optical encoder, which recorded probing force to a computer when a button was pressed. The probe handpiece included a 0.40 mm diameter hemispherical tip which was placed in contact with the experimental site. The probe tip was pressed against the tissue with increasing force until the subject pressed the button, at which point the pain tolerance (PT) value was recorded by the computer. Intraoral soft tissue, PT values were obtained from nine healthy adult subjects during 6 weekly visits to determine the reproducibility of PT measurements. Five gingival sulcus sites and three gingival surface sites, all adjacent to the maxillary premolars constituted the experimental area. The reproducibility of PT values using the force stimulus from the algometer was evaluated using interclass correlation coefficients (R) for each of the eight sites. Visits 1 and 2 were training and calibration visits. Visits 3 through 6 were experimental visits. The R values ranged from 0.40 to 0.79 when data from all six visits were included. R values for Visits 3 through 6 were 0.63-0.97 indicating good to excellent correlation after subjects became familiar with the procedure. A complete repeated measures analysis of variance (ANOVA) showed no significant interaction between site and visit. Duncan's multiple range test was used to compare sensitivity across the eight sites. The results indicated that the three most anterior sites were significantly (P < 0.05) more sensitive than four of the posterior sites. When the sites were grouped into: (1) gingival surface sites; (2) mid-facial sulcus sites; and (3) interproximal sulcus sites, no significant differences were found in their PT values. The algometer is well suited for intraoral investigations because of its precision, computerized data entry and easily positioned, autoclavable handpiece. This new algometer may be useful for sensory and pain studies for other parts of the body.

Pain threshold values during periodontal probing: assessment of maxillary incisor and molar sites.

Probing pain threshold (PPT) assessments were conducted in the facial and oral sulci of maxillary central incisors and first molars of 10 periodontally healthy adults. All subjects were systemically healthy, free of pain, and reported no current medication usage. A computer-linked electronic probe, modified to deliver steadily increasing forces up to 200 grams, was used to collect the data. The system contained a subject operated "off-switch" which, upon activation, signaled the computer to record the subject's PPT. Assessments of each subject's PPTs were conducted on 3 separate occasions at 7-day intervals. Results indicated that the facial sulci of the incisors were the most pain sensitive. They displayed a mean PPT of 50.9 +/- 26.6 grams. The oral sulci of the incisors exhibited a mean PPT of 76.5 +/- 45.2 grams. Facial and oral sulci of the molars evidenced mean PPT values of 102.6 +/- 52.1 grams and 113.5 +/- 51.3 grams, respectively. These data suggest that sulci associated with incisor teeth are nearly twice as pain sensitive as sulci associated with molar teeth. In addition, facial sulci are significantly more pain sensitive than oral sulci. Data did not indicate a visit effect nor a side-of-mouth effect on PPT values.

Periodontal probe use in general practice in Florida.

Use of the periodontal probe in 134 Florida dental practices was studied. Results indicated that 62% of the practices performed a complete recorded periodontal probing for new patients. Recall patients received a complete recorded periodontal probing in 57% of the practices at a mean frequency of 12.7 months. Selected site probing was performed in 22% of the offices as part of the new patient examination, and in 34% of the offices as part of the recall examination. In the examinations in 57% of the practices, changes in pocket depths were detected that could suggest changes in connective tissue levels.

Correlation between electronic and visual readings of pocket depths with a newly developed constant force probe.

The purpose of this study was to compare probing measurements obtained using a newly developed constant force electronic probe, which eliminates errors of visual reading and variable force, to those obtained using a standard periodontal probe. The probe was connected to a digital readout through a linear variable differential transformer; the digital readout was connected to a printer and a foot switch. When the probe was in position and the foot switch depressed, the pocket depth was printed to the nearest 0.1 mm. 12 subjects with minimal to early periodontitis were selected for the study. The pocket depths of each patient were recorded electronically utilizing a constant force of 25 g, and conventionally using the same instrument in a "locked" position and visual reading. Probings were performed on each subject by 3 different examiners, on 3 separate occasions 2-3 days apart. The results showed a high correlation between manual and electronic probing. The average correlations for the 3 investigators between examinations were consistently higher for the electronic probings. In comparing the 3 examiners to each other, consistently higher correlations were found for the electronic pocket readings. Correlations for single-rooted teeth were lower for all 3 examiners. The pocket depth measurements recorded when using the manual probe with visual readings were consistently deeper than those obtained using the electronic probe with computer readings. It was concluded that the reproducibility of measurements obtained with the electronic probe was significantly superior to that obtained with a manual probe.

The relationship of interradicular width and alveolar bone loss. A radiometric study of a periodontitis population.

Contrasting data exist on the relationship between interproximal width and loss of marginal bone in a periodontitis susceptible population. Reports of clinical observations suggest that the prognosis of teeth with minimal interradicular width should be downgraded in periodontal patients. Others indicate a higher prevalence of intrabony lesions in wider interproximal spaces. Radiographs of 114 adult patients with evidence of bone loss consistent with periodontitis were examined. Measurements of interradicular width and the location of the bone margin from the cementoenamel junction were made at 811 interproximal sites using an optical digitizer at 3X magnification. The relationship between bone loss and interradicular width was investigated. The results indicate that as the interradicular width increases, the interproximal bone margin tends to be in a more apical location. No findings supported the contention that bone in a narrow interradicular space is at greater risk in patients who have had periodontitis.

Inquiry teaching in clinical periodontics.

Inquiry teaching is a strategy to develop skills in information retrieval and reasoning. Its framework is a method of systematic questioning by the teacher, who trains the learner's skill in information retrieval and thinking so that future clinical problems may be more readily solved. This paper describes the adaptation of the Inquiry Method to instruction in clinical periodontics. It describes a strategy that structures the interactions between the teacher and student to develop thinking skills related to patient care.

A histologic study of the width and nature of inter-radicular spaces in human adult pre-molars and molars.

Serial sections of jaw segments from a human post mortem population of 29 individuals providing 116 posterior interproximal sites were examined at the light microscopic level. Minimum inter-root distances at the locale of closest proximity ranged from more than 4 mm to less than 0.1 mm. They were located in the coronal third of pre-molars and mandibular first and second molars and the middle third of maxillary first molars and second molar interproximal spaces. Cancellous bone flanked by lamina dura was found between 89.6% of the teeth examined and was observed where inter-root distances exceeded 0.5 mm. At sites of less than 0.5 mm, cancellous bone was not observed, and, instead, adjacent laminae durae appeared fused (7.7%). Bone was not observed between root surfaces which were less than 0.3 mm apart, but in these instances the roots were connected by a periodontal ligament.

An analysis of behavioral contingencies in clinical teaching.

Principles of a contingency management were applied in analyzing student reports on clinical instruction. In behavioral science, a contingency is a relationship between a behavior and its effect. The analysis identifies contingencies arranged by clinical instructors that unintentionally interfere with learning. The faculty responded to the findings by planing changes to overcome the problems identified. Prior to the study, many of the problems uncovered were not recognized by the faculty. Students are usually not open about such sensitives areas of feedback. If dental faculty members of other institutions do not feel that similar findings apply to their schools, the authors recommend that they conduct an analogous study.

Teaching clinical judgment in periodontics.

Clinical judgment is a complex process that is difficult to develop. It is the essence of the health professional, yet most dental curricula do not emphasize the learning of the judgmental process. In this paper the judgmental process is analyzed into three components: input, mediation, and output. Following the analysis, suggestions for using these components are presented in four instructional phases: the introductory phase, the initial guidance phase, the application phase, and the feedback phase. While the illustrations used are drawn from periodontics, the principles are generalizable to the teaching of all clinical disciplines.