OBJECTIVES Patient engagement in effective oral hygiene following periodontal therapy is essential to long-term success. Motivational interviewing (MI) is a behavioural counselling approach documented to positively influence behaviour change related to smoking, diabetes control and medication adherence. Emerging evidence suggests utility of MI to improve oral health. The objective of this study was to evaluate whether the use of brief motivational interviewing (BMI) is effective in improving internal motivation for oral hygiene behaviour. METHODS A convenience sample of fifty-six previously treated periodontal patients who were in maintenance yet presented with signs of clinical inflammation were recruited to participate in this single blind, randomized controlled trial. Patients were randomly assigned to receive either BMI in conjunction with traditional oral health education (TOHE), (n = 29) or TOHE alone (n = 27). Bleeding on probing scores (BOP), plaque index (PI), pocket depths (PD), motivation (M), autonomous regulation (AR) controlled regulation (CR) and oral health knowledge (K) were assessed at baseline, 6 weeks and 12 weeks. RESULTS Statistically significant decreases were found over time for BOP (P = 0.001), PI (P = 0.001) and PD 4-6 mm (P = 0.001) for both groups. Differences in clinical parameters between groups were not evident at either 6 or 12 weeks. CONCLUSION Results show that a one-time MI session is insufficient for improving oral hygiene in long-standing maintenance patients.

Background: The clinical efficacy and safety of doxycycline hyclate (8.5% w/w) delivered subgingivally in a biodegradable polymer (DH) was compared to placebo control (VC), oral hygiene (OH), and scaling and root planing (SRP) in 2 multi‐center studies.Methods: Each study entered 411 patients who demonstrated moderate to severe periodontitis. Patients had 2 or more quadrants each with a minimum of 4 qualifying pockets ≥5 mm that bled on probing. At least 2 of the pockets were ≥7 mm. Treatment with DH, VC, OH, or SRP was provided at baseline and again at month 4. Clinical parameters were recorded monthly.Results: DH and SRP resulted in nearly identical clinical changes over time in both studies. Mean 9 month clinical attachment level gain (ALG) was 0.8 mm for the DH group and 0.7 mm for the SRP group in Study 1, and 0.8 mm (DH) and 0.9 mm (SRP) in Study 2. Mean probing depth (PD) reduction was 1.1 mm for the DH group and 0.9 mm for the SRP group in Study 1 and 1.3 mm for both groups in Study 2. Frequency distributions showed an ALG ≥2 mm in 29% of DH sites versus 27% of SRP sites in Study 1 and 31% of DH sites versus 34% of SRP sites in Study 2. PD reductions ≥2 mm were seen in 32% of DH sites versus 31% of SRP sites in Study 1 and 41% of DH sites versus 43% of SRP sites in Study 2. Comparisons between DH, VC, and OH treatment groups showed DH treatment to be statistically superior to VC and OH. Safety data demonstrated a benign safety profile with use of the DH product.Conclusions: Results of this trial demonstrate that treatment of periodontitis with subgingivally delivered doxycycline in a biodegradable polymer is equally effective as scaling and root planing and superior in effect to placebo control and oral hygiene in reducing the clinical signs of adult periodontitis over a 9‐month period. This represents positive changes resulting from the use of subgingivally applied doxycycline as scaling and root planing was not limited regarding time of the procedure or use of local anesthesia. J Periodontol 1999;70:490‐503.

The purpose of the present study was to compare the in vitro effects of a mechanical and a sonic toothbrush on the viability of Actinomyces viscosus , the rationale being that induction of irreparable microbial damage resulting from aggressive mechanical action or sonic energy, may inhibit or disrupt the process of successional colonization. Cultures of A. viscosus were grown to a standardized optical density and subdivided into 3 treatment groups of 20 specimens each. Treatment groups consisted of an untreated control and exposure to a mechanical or sonic toothbrush for 15, 30, 45, and 60 s. Subsequent to the prescribed treatment, samples were taken from each specimen dish, subcultured, and the number of CFUs determined. Additional samples were obtained for negative staining and examination by electron microscopy. The mean number of CFUs for each treatment group at each treatment interval were statistically analyzed by ANOVA and multiple pairwise comparisons. Results showed a significant main effect for toothbrushes ( p < 0.0001) and exposure time ( p < 0.01), but only marginal significance for the interaction of toothbrush with exposure time ( p 0.055). Posthoc tests showed a significantly greater number of CFUs for the sonic toothbrush compared to both the untreated control and mechanical toothbrush groups. Electron microscopic examination revealed a decrease in aggregation tendency and loss of fimbriae in the sonic toothbrush group. Based on the lack of morphologic evidence that would indicate cell damage and the increase in CFUs over that of the control group, it appeared that neither the mechanical or sonic toothbrushes affected cell viability.

The Nd:YAG and CO2 lasers have been shown to be bactericidal at relative low energy densities. However, at energy densities exceeding 120 J/cm2 (CO2) and 200 J/cm2 (Nd:YAG), laser irradiation also causes irreparable root surface damage. The purpose of this study was to determine, in vitro, the energy density threshold at which microbial ablation could be achieved while inflicting the least amount of damage to the root surfaces of human teeth. Pairs of Escherichia coli colonies cultured on broth agar were treated with a CO2 laser using a pulsed waveform at approximate energy densities ranging from 3 to 110 J/cm2. One of each colony-pair was then examined by scanning electron microscopy (SEM) and the other subcultured for viable microbes. Roots of extracted teeth were lightly scaled and treated by CO2 laser, again with pulsed beam using approximate energy densities of 3 to 110 J/cm2: and examined by SEM. Regardless of the level of energy density, residual bacteria could be subcultured from all laser treated microbial colonies. The inability of the laser to completely obliterate microbial colonies was likely due to: depth of energy penetration, difficulty in precisely overlapping beam focal spots, irregular beam profile, and presence of microbes at the periphery of the beam focal spot. The threshold energy density for bacterial obliteration was determined to be 11 J/cm2 and that for root damage was 41 J/cm2. Root damage was evident by charring, crater formation, melt-down and resolidification surface mineral, and increasing surface porosity. The results of this in vitro study indicate that when used at an energy density between 11 and 41 J/cm2 the CO2 laser may destroy microbial colonies without inflicting undue damage to the tooth root surface.

This study examined the effects of tetracycline hydrochloride (TCN) and chlorhexidine gluconate (CHX) on the growth and viability of Candida albicans. Subcultures of Candida albicans on Sabouraud's agar, were divided into 5 treatment groups: group 1, untreated control; group 2, 0.12% CHX; group 3, 3.0 mg/ml TCN adjusted to pH 4.5; groups 4 and 5, sodium azide free Tris buffer adjusted to pH 4.5 and pH 7.4, respectively. All groups were incubated for 10 days, and sampled and subcultured daily to determine the viability of each group. Additional samples from group 2 (day 4), group 4 (day 7) and all groups at day 10 were selected for SEM and TEM examination. Visual, SEM and TEM results showed that for groups 1, 3, 4, and 5 there was a heavy and constant uniform growth of Candida albicans throughout the period of the study. However, group 2 (CHX), showed decreasing viability and attachment from day 3 to day 10, with SEM and TEM revealing decreased blastospores and profound changes in the ultrastructural morphology, indicating inhibition of normal cell growth and replication. These results show that TCN even when used at high concentrations, in vitro, will allow uninhibited growth of Candida albicans whereas CHX inhibits cell growth and replication.