Probe penetration in relation to the connective tissue attachment level: influence of tine shape and probing force

Abstract. Previous research has shown that probing force and probe tine shape influence the clinically assessed probing depth. The purpose of the present study was to investigate the effect of tine shape and probing force on probe penetration, in relation to the microscopically assessed attachment level in untreated periodontal disease. In 22 patients, scheduled for partial or full mouth tooth extraction and no history of periodontal treatment, 135 teeth were selected. At mesial and distal sites of the teeth reference marks were cut. Three probe tines, mounted in a modified Florida Probe® handpiece, were tested: a tapered, a parallel and a bail-ended; tip-diameter 0.5 mm. The three tines were distributed at random over the sites. At each site increasing probing forces of 0.10 N, 0.15 N, 0.20 N, 0.25 N were used. After extraction, the teeth were cleaned and stained for connective tissue fiber attachment. The distance between the reference mark and the attachment level was determined using a stereomicroscope. The results showed that the parallel and ball-ended tine measured significantly beyond the microscopically assessed attachment level at all force levels; with increasing forces, the parallel tine measured 0.96 to 1.38 mm and the ball-ended tine 0.73 to 1.06 mm deeper. The tapered tine did not deviate significantly from the microscopic values at the forces of 0.15. 0.20 and 0.25 N. It can be concluded that for the optimal assessment of the attachment level in inflamed periodontal conditions, a tapered probe with a tip diameter of 0.5 mm and exerting a probing force of 0.25 N may be most suitable.     

Antifungal effect of zeolite-incorporated tissue conditioner against Candida albicans growth and/or acid production

summary A new antimicrobial material, Ag-zeolite (Zeomic^°), was combined with a commercial tissue conditioner (GC-Soft Liner (GC); 1–5%) and, through monitoring the pH of the growth medium, examined for effects on the in vitro growth and/or acid production of Candida albicans on protein-free and saliva-coated specimens. The effect of incorporation of this agent on the physical property of the lining material was also examined according to the ISO penetration test. Comparison studies were carried out using GC, Coe Comfort (CC) or undecylenate combined GC (1–5%) specimens. Although the pH changes in the media varied depending upon the materials on which the Candida was grown, reverse sigmoidal pH curves were observed with most samples. As compared with GC, the soft lining materials showed, to some extent, an inhibitory effect on the acid production and/or the growth of C. albicans. These inhibitory effects consisted of a delay in the onset of rapid pH decline, decreases in the rate of pH change and increases in minimum pH. In most cases, the inhibitory effects of test specimens were dose-dependent, and zeolite specimens showed a significantly higher antifungal effect, followed by CC and undecylenate-combined GC; GC showed the least antifungal effect. The inhibitory effects of these materials on fungal growth were decreased by the presence of a saliva-coat, particularly with zeolite specimens and CC. However, four of eight 5%-Zeomic^° specimens still exhibited perfect growth inhibition in the presence of the salivary pellicle. Furthermore, test specimens containing 2–5% Zeomic^° showed a significantly greater effect on the delay in rapid decline of pH, as compared with the other specimens examined. In addition, the significantly higher minimum pH was observed where the yeasts were grown on 4%- and 5%-Zeomic^° specimens. The physical properties of all the test specimens conformed with the ISO standard as examined by penetration test. These results taken together suggest that an antimicrobial zeolite-combined tissue conditioner would be a potential aid in denture plaque control.     

The Dental Student as Technician: An 18-Year Follow-Up of Clinical Laboratory Programs

In 1977, a survey of American and Canadian dental schools was conducted by Weintraub to determine the delegation of laboratory procedures in preclinical and clinical complete and removable partial denture programs. This was performed in light of challenges raised to the value of requiring dental students, rather than laboratory technicians, to perform the various laboratory procedures involved in the fabrication of complete and removable partial dentures. Since 1977, the rate of edentulism has declined in the United States, and fewer edentulous patients have sought regular dental care. In addition, approximately 20% fewer curriculum hours have been spent in dental schools in removable prosthodontic instruction; a declining number of graduating dental students have felt comfortable with their level of knowledge of removable prosthodontics, especially complete dentures, and have performed fewer removable prosthodontic procedures in practice because of a perceived lack of treatment cost-effectiveness. The present study, an 18-year follow-up to the 1977 survey, was designed to determine if such trends toward a deemphasis on removable prosthodontic treatment have affected the mechanisms of instruction in and the extent to which dental schools instruct students about removable-prosthodontics laboratory procedures. The 1995 survey was mailed to 53 American dental schools. Forty-six schools returned the completed survey, for a response rate of 87%. Results showed that the relative amount of material presented to students in clinical removable prosthodontics programs increased, primarily through the enhancement of laboratory technician support, both in-house and commercial, of student clinical removable prosthodontic laboratory procedures. The increase was greater than in preclinical removable prosthodontic programs, which were described in a companion article. The conflict between these outcomes and the call by the dental community, as well as that of the 1995 Institute of Medicine Study, for a reduced emphasis on teaching students about the technical details involved in removable prosthesis fabrication is recognized and explored.     

Retreatment efficacy of the Epiphany soft resin obturation system

AIM: To assess the efficacy of retreatment of canals filled with the Epiphany System with and without solvent, with particular reference to the extent of canal enlargement during retreatment. METHODOLOGY: Sixty roots with canals prepared to apical size 45 were embedded in resin blocks and sectioned vertically. Digital micrographs of canal walls were captured. Roots were re-assembled and filled with Epiphany/Resilon (experimental) or gutta-percha/AH Plus (control). After 8 weeks, canals were retreated to size 45 with or without chloroform, and the time recorded. Roots were split, imaged, re-assembled, retreated to size 55, split and imaged. Root-filling residue, traced at three canal levels, was expressed as percentage of canal surface. RESULTS: Residue percentage was greater (t-test, P < 0.01) in the experimental group than in the control. Most residue in all specimens was in the apical third (ANOVA, P < 0.01). Chloroform and enlargement to size 55 decreased residue in both groups (t-test, P < 0.01). Retreatment time was longer in the experimental group (P < 0.05), and reduced by chloroform in both groups (P < 0.05). CONCLUSIONS: The Epiphany System was retreatable with and without chloroform, with lesser efficacy than gutta-percha and AH Plus sealer.     

A global perspective on changes in the burden of caries and periodontitis: implications for dentistry

The structure and contents of most oral health care systems and the contents of dental curricula reflect a deep-rooted tradition for attempting to cure oral diseases by refined technological means. However, better oral health conditions for the world's populations necessitate the application of up-to-date scientific knowledge to control the major oral diseases. This review points out that not only should the structure and contents of oral health care delivery systems be based on state-of-the-art knowledge about the biology of the oral diseases; they must also take into account the trends for change in caries and periodontal diseases within and between populations, and acknowledge the impact of changes in treatment philosophies for these trends. The oral disease profiles for populations in low- and high-income countries are briefly described, and it is concluded that the rapidly changing disease profiles observed in high-income countries necessitate re-thinking of the future role and organization of dentistry in such countries. The priorities for low- and middle-income countries must be to avoid repeating the mistakes made in the high-income countries. Instead, these societies might take advantage of setting priorities based on a population-based common risk factor approach. If such an approach is adopted, the training of personnel with oral health care competence must be rethought. The authors suggest three different cadres of dental care providers to be considered for an approach that allows health care planners in different populations around the world to prioritize appropriate oral health care with due respect for the socio-economic conditions prevailing.     

Clinical significance of holes in gloves for dental use: a spectrophotometric analysis.

The aim of this study on latex dental gloves was to establish whether there is any relationship between faults that are detected by filling with water and the entry of liquid into the gloves during use. Twenty-four gloves of different sizes were examined. Large and small holes randomly distributed on the index, middle, and ring fingers, were made in the gloves. The gloves were filled with water and squeezed to detect the amount of water escaping. A mass spectrophotometer was used with the same gloves to quantify the entry of an aqueous solution of potassium bichromate during work. The filling method was effective for revealing all faults in gloves, but it was not able to determine whether there would be fluid entry through the holes during work. While the size of the holes was not predictive for the amount of liquid entering the glove, adherence of the glove to the hand was. Holes of the same size allowed a greater entry of contaminated liquid in adherent gloves than in looser ones.     

Use of transcutaneous electroneurostimulation for enhancing the effectiveness of conduction anesthesia in dental polyclinic practice

The efficiency of mandibular conduction anesthesia was assessed in patients with inflammatory disorders in the area innervated by the mandibular nerve. In patients with conduction anesthesia induced after an electroneurostimulation session, the efficiency of anesthesia was considerably higher than in those operated on under mandibular anesthesia only.