A comparison of the effectiveness of hand scaling and ultrasonic debridement in furcations as evaluated by differential dark-field microscopy

Diagnosis and Management of Furcation Lesions in Dogs - A Review

The furcation is the anatomic area where the roots divide on a multirooted tooth. Periodontal disease causing alveolar bone loss can lead to furcation lesions of various stages. Once furcation involvement has occurred, the area can be more difficult to clean or treat due to the complex anatomy and morphology of furcations. Teeth with short root trunks, longer tooth roots, and roots with wide furcation entrance areas/degrees of separation and wide root divergence are considered better candidates for long term maintenance. Dog teeth possess many of these advantageous anatomic features compared to human teeth. Treatment options for teeth with furcation lesions include: closed debridement, open debridement, furcation plasty, tunneling, partial tooth or root resection, root separation (hemisection or trisection), regenerative therapies, or exodontia. There are many factors to consider in determining treatment options. The favorable and unfavorable characteristics for maintenance of teeth with furcation lesions are summarized. Home care and ongoing professional care are important aspects of periodontal disease control for any patient. Studies of systemic and local antibiotic therapies in human patients have not demonstrated reduction of furcation stages, and probiotic effects at furcation sites have not been specifically examined. Human review studies show that most molar teeth once deemed "hopeless" due to stage 3 furcation lesions can be maintained for at least 5 to 15 years with supportive periodontal therapy. Similar long term studies in dogs are needed to improve the evidence-based management of canine patients with furcation lesions.

Erbium-doped: yttrium-aluminum-garnet (Er:YAG) versus scaling and root planing for the treatment of periodontal disease: A single-blinded split-mouth randomized clinical trial

BACKGROUND

This randomized, controlled clinical trial aimed to compare the differences in periodontal clinical outcomes, duration of the procedure, and patient's experience between conventional scaling and root planing and erbium-doped: yttrium-aluminum-garnet (Er:YAG) in the treatment of generalized moderate to severe chronic periodontitis or generalized Stages II or III, and Grade B periodontitis based on the Centers for Disease Control (CDC), American Academy of Periodontology (AAP), and European Federation of Periodontology (EFP) definitions.

METHODS

Thirty subjects were initially recruited. In a split-mouth fashion, right and left sides were randomly allocated into two treatment arms: conventional scaling and root planing (C-SRP) versus laser-assisted scaling and root planing (L-SRP). A blinded examiner recorded clinical measurements at baseline and 3 months. Duration of the procedure was also recorded for each visit, and the patient's experience was assessed with a questionnaire at baseline, 1, and 3 months.

RESULTS

The final sample consisted of 26 subjects. Both treatments resulted in overall improvement, but no significant differences were found between modalities for clinical attachment gain or probing depth reduction. The duration of the procedure was approximately half for L-SRP, and postoperative sensitivity was greater in C-SRP.

CONCLUSIONS

The low-energy protocol with Er:YAG (50 mJ) used for the non-surgical treatment of moderate-severe chronic or Stage II-III, Grade B periodontitis performed in this study population was a treatment modality that yielded similar clinical improvements when compared to conventional scaling and root planing.

A comparative questionnaire study of patient complaint levels between magnetostrictive ultrasonic scaler (Cavitron® ) and piezoelectric ultrasonic scalers

OBJECTIVES

Ultrasonic scalers often cause an uncomfortable feeling to patients during the procedure. This study was conducted to compare patient complaint levels between magnetostrictive (M-USSC) and piezoelectric ultrasonic scalers (P-USSC) during supragingival scaling.

METHODS

This study enrolled 82 subjects who received supportive periodontal therapy for at least 2 years. At each recall visit, probing pocket depth (PPD), bleeding on probing (BOP) and O'Leary plaque control record (O'PCR) were recorded. Then, supragingival scaling was performed using P-USSC (Varios or Petit Piezo) at the first visit and M-USSC (Cavitron) at the second visit. After each treatment, a questionnaire survey was performed using the Wong-Baker Faces Pain Scale for six items, which included the typical complaints occurring during ultrasonic scaling.

RESULTS

The scores for all the six items related to patient complaints were greater for P-USSC than for M-USSC (p < 0.001). Patient complaints such as discomfort, pain, sound, vibration, hyperesthesia and length of treatment time were ameliorated in 74%, 65%, 80%, 67%, 57% and 53% of subjects using M-USSC, respectively. On the other hand, only <5% of subjects showed deterioration in terms of each complaint.

CONCLUSION

This study suggested that M-USSC causes fewer patient complaints during supragingival scaling than P-USSC. M-USSC may improve patient motivation and compliance and may contribute towards achieving successful treatment outcomes. However, this result could differ depending on the shape of the tip and the insert and treatment site. Further research will be required under various conditions.

A clinicoradiographic assessment of 1% metformin gel with platelet-rich fibrin in the treatment of mandibular grade II furcation defects

Background:

Management of furcation defects is challenging, and constantly newer therapeutic strategies are evolving. Platelet-rich fibrin (PRF) is successfully used alone and in combination with various agents in the furcation defects. Lately, metformin (MF), a second generation biguanide has gained popularity owing to its osteogenic potential.

Aims and Objectives:

The aim of the present study was to evaluate the clinical and radiographic effectiveness of open flap debridement (OFD) and PRF when compared to OFD + PRF + 1% MF gel in the management of mandibular Grade II furcation defects.

Materials and Methods:

Thirty mandibular grade II furcation defects were stratified into two groups; in one group OFD and PRF is used, and the other group had an additional MF gel with PRF in OFD. Clinical parameters such as plaque index, modified sulcus bleeding index, probing pocket depth (PD), relative vertical attachment level (RVAL), and relative horizontal attachment level (RHAL) were recorded at baseline and at 6 months. Radiovisiography and ImageJ software were used to evaluate the intrabony defect depth.

Results:

The OFD + PRF + MF group showed significantly higher probing PD reduction, RVAL and RHAL gain than the OFD + PRF group.

Conclusions:

PRF when combined with a potential osteogenic agent like MF can provide a better therapeutic benefit to a furcation involved tooth.

Comparison of Root Surface Roughness Produced By Hand Instruments and Ultrasonic Scalers: An Invitro Study

BACKGROUND

Instrumentation on tooth surface for debridement of hard and soft debris forms the basis of periodontal therapy. This involves periodic removal of accumulated material using different methods of instrumentation. An ideal instrument should eliminate all the deposits from the root surfaces with no or minimal alteration of the natural morphology.

AIM

To compare the root surface roughness after root planing performed with gracey curette and by ultrasonic scalers (Satelec P-5 Booster) set at different power modes.

MATERIALS AND METHODS

The root surface roughness and its surface microtopography resulting from the use of Gracey curette, ultrasonic instrument at low, medium and high power setting on 35 healthy premolars extracted for orthodontic treatment purpose were examined using Optical Profilometer and the surface topography was assessed using Field Emission Microscope.

STATISTICAL ANALYSIS

Analysis of variance (ANOVA) test was used to observe the variance in a particular variable is partitioned into components attributable to different sources of variation. Duncan multiple range tests were used to determine whether three or more means differ significantly.

RESULTS AND CONCLUSION

The mean roughness was found to be the highest in group where Scaling and Root Planing (SRP) was performed using ultrasonic scaler at low power mode (3.03±1.54 μm) whereas the lowest surface roughness was seen on the samples where SRP was performed using ultrasonic scaler at medium power mode. The surface roughness in group where SRP was performed with ultrasonic scaler at high power mode (2.22±0.74μm) was found to be similar to that of group in which root planing was carried out using curette (2.24±1.71μm).

Non-surgical periodontal therapy: An update on current evidence

Periodontal disease is an inflammatory condition that involves a complex interaction between pathogenic bacteria, environmental and acquired factors and host related factors. Till recently periodontal treatment was directed primarily towards reduction of bacterial load by subgingival debridement of root surfaces and modification of environmental risk factors. The current paradigm of periodontal disease stresses greater role of host-mediated inflammatory response in tissue destruction characteristic of periodontal disease. Various therapeutic modalities have been developed adjuvant to mechanical periodontal therapy. The use of laser and photodynamic therapy show great promise but their effectiveness has still not been conclusively proven. Chemotherapeutic agents, either systemic and local antimicrobials or host modulating drugs, played pivotal role in better and more predictable management of periodontal disease. The present review focuses on the best available evidence, for the current management of the chronic periodontal patients, gathered from systematic reviews and meta-analysis of mechanical non surgical periodontal therapy (NSPT) (subgingival debridement, laser therapy and photodynamic therapy) and the adjunctive chemotherapeutic approaches such as systematic and local antibiotics and antiseptics, subgingival pocket irrigation and host modulation therapies. The review also attempts to briefly introduce future developments in some of these modalities. At the end, the review summarizes the analysis of the current evidence that suggests that thorough subgingival debridement remains the mainstay of NSPT and that adjunct use of chemotherapeutic agents may offer better management of clinical parameters in periodontitis patients.

Time to shift: from scaling and root planing to root surface debridement

Non-surgical periodontal treatment has traditionally been based on the notion that bacterial plaque (dental biofilm) penetrates and infects dental cementum. Removal of this infected cementum via scaling and root planing (SRP) was considered essential for re-establishing periodontal health. In the 1980s the concept of SRP was questioned because several in vitro studies showed that the biofilm was superficially located on the root surface and its disruption and removal could be relatively easily achieved by ultrasonic instrumentation of the root surface (known as root surface debridement (RSD). Subsequent in vivo studies corroborated the in vitro findings. There is now sufficient clinical evidence to substantiate the concept that the deliberate removal of cementum by SRP is no longer warranted or justified, and that the more gentle and conservative approach of RSD should be implemented in daily periodontal practice.

Non-surgical instrumentation associated with povidone-iodine in the treatment of interproximal furcation involvements

Objective

The aim of this controlled clinical trial was to evaluate the effect of topically applied povidone-iodine (PVP-I) used as an adjunct to non-surgical treatment of interproximal class II furcation involvements.

Material and methods

Thirty-two patients presenting at least one interproximal class II furcation involvement that bled on probing with probing pocket depth (PPD) ≥5 mm were recruited. Patients were randomly chosen to receive either subgingival instrumentation with an ultrasonic device using PVP-I (10%) as the cooling liquid (test group) or identical treatment using distilled water as the cooling liquid (control group). The following clinical outcomes were evaluated: visible plaque index, bleeding on probing (BOP), position of the gingival margin, relative attachment level (RAL), PPD and relative horizontal attachment level (RHAL). BAPNA (N-benzoyl-Larginine-p-nitroanilide) testing was used to analyze trypsin-like activity in dental biofilm. All parameters were evaluated at baseline and 1, 3 and 6 months after non-surgical subgingival instrumentation.

Results

Six months after treatment, both groups had similar means of PPD reduction, RAL and RHAL gain (p>0.05). These variables were, respectively, 2.20±1.10 mm, 1.27±1.02 mm and 1.33±0.85 mm in the control group and 2.67±1.21 mm, 1.50±1.09 mm and 1.56±0.93 mm in the test group. No difference was observed between groups at none of the posttreatment periods, regarding the number of sites showing clinical attachment gain ≥2 mm. However, at 6 months posttreatment, the test group presented fewer sites with PPD ≥5 mm than the control group. Also at 6 months the test group had lower BAPNA values than control group.

Conclusion

The use of PVP-I as an adjunct in the non-surgical treatment of interproximal class II furcation involvements provided limited additional clinical benefits.

Microscope-controlled glass bead blasting: a new technique

OBJECTIVE

The aim of periodontal therapy is the healing of periodontal inflammation; the protection of the attachment and the alveolar bone; and the regeneration of the periodontal structures. In the therapy of periodontitis, supra- and subgingival scaling and root planing plays a main role. The procedure described combines perfect root cleaning without scaling and root planing and minimal invasive periodontal surgery without a scalpel.

MATERIAL AND METHODS

Glass beads of 90 μm were used with the kinetic preparation unit PrepStart(®) under a pressure of 0.5-5 bar. This technique was practised only under visual control using the OPMI(®) PRO Magis microscope. Seven examinations were carried out at baseline after 3, 6, 12, 18, 24, and 36 months.

RESULTS

Time shows a statistically significant influence on all of the considered target variables (P < 0.0001 for all). As the according estimate is negative, probing depth decreases over time. The major decrease seems to be during the first 6 months. Considering probing depth, plaque on the main effect root shows significant influence (again, P < 0.0001 for all). Observations with high probing depth at the beginning were faster than those with low probing depth. The same characteristic appears by attachment level. Patients with more loss of attachment show more gain.

CONCLUSIONS

Using microscope-controlled glass bead blasting results in a perfectly clean root surface using visual control (magnification 20×). Microscope-controlled glass bead blasting is therefore a good alternative to periodontal surgery.

Periodontal therapy

Periodontal disease is the most common disease in small animal patients. It not only creates severe localized infection, but it has been linked to numerous severe systemic maladies. Proper therapy of this disease process results in a significant increase in the overall health of the patient. The treatment of periodontal disease is currently evolving due to the acceptance of the specific plaque hypothesis of periodontal disease. These findings have led to the development of the "one-stage full-mouth disinfection" treatment as well as a vaccine against these organisms. However, the cornerstone of therapy is still meticulous plaque control. This control is achieved via a combination of regular dental prophylaxis and home care. With progressive disease, advanced periodontal surgery or extraction becomes necessary.

Immunohistochemical characterization of periodontal wound healing following nonsurgical treatment with fluorescence controlled Er:YAG laser radiation in dogs

BACKGROUND AND OBJECTIVE

The aim of the present study was to immunohistochemically characterize periodontal wound healing following nonsurgical treatment with fluorescence controlled Er:YAG laser radiation in dogs.

STUDY DESIGN/MATERIALS AND METHODS

Five beagle dogs suffering from naturally occurring chronic periodontitis were randomly allocated in a split-mouth design to nonsurgical periodontal treatment using either (a) an Er:YAG laser at 10.2, 12.8, 15.4, 18, and 20.4 J/cm2 (ERL1-5), or (b) an ultrasonic device (VUS) serving as control. The animals were sacrificed after 3 months. Histomorphometrical (e.g. inflammatory cell infiltrate, surface changes, cementum formation), and immunohistochemical parameters (collagen type I, CD68, matrix metalloproteinase (MMP)-8) were assessed.

RESULTS

Inflammatory cell infiltrates of different extent were commonly observed in all treatment groups. However, histomorphometrical analysis revealed new cementum formation with inserting collagen type I fibers along the instrumented root surfaces in most specimens of both ERL (ERL2: 31+/-81 to ERL5: 595+/-575 microm) and VUS (50+/- 215 microm) groups. This was associated with pronounced CD68 and weak MMP-8 antigen reactivity.

CONCLUSION

Within the limits of the present study, it was concluded that both treatment procedures (i) were effective in controlling inflammatory cell infiltrates, and (ii) may support the formation of a new connective tissue attachment.

Subjective intensity of pain during ultrasonic supragingival calculus removal

OBJECTIVE

To assess subjective intensities of pain during supragingival calculus removal employing ultrasonic scaler tips of two different shapes.

MATERIAL AND METHODS

Twenty patients were treated using a piezoelectric ultrasonic device (Sirosonic L) and two different scaler tips representing a conventional (Instrument No. 3) and a slim-line style (Perio Pro Line Instrument SI-11) in a split-mouth design. Pain was recorded during calculus removal at intervals of 0.5 s employing an inter-modal intensity comparison. Additionally, a visual analogue scale was used for evaluation directly after the treatment procedure. Treatment time was recorded to assess the efficiency of calculus removal.

RESULTS

Pain assessment during treatment showed that the slim-line scaler tip (median pain score: 1.4 [U], maximum: 3.5 [U], minimum: 0 [U]) caused less pain than the conventional device (median pain score: 7.8 [U], maximum: 14.7 [U], minimum: 0 [U]) (p<0.05). These results could be confirmed by the visual analogue scale. Treatment with the slim-line tip took significantly longer than treatment with the conventional tip (p<0.05).

CONCLUSIONS

Using slim-line-styled ultrasonic scaler tips for supragingival calculus removal, painful sensations can be reduced compared with conventional ultrasonic devices. Thus, it might be possible to increase the patient's compliance during dental treatment with oscillating instruments.

Clinical effects after subgingival polishing with a non-aggressive ultrasonic device in initial therapy

OBJECTIVES

The Vector ultrasonic system provides root debridement supported by different abrasive irrigation fluids. The aim of this study was to investigate the clinical outcome of initial therapy with subgingival low-abrasive debridement.

MATERIAL AND METHODS

Twenty patients, who had at least two teeth with pocket depths >5 mm in each quadrant, took part in this prospective randomized clinical study. Patients were treated in a split-mouth design as one test quadrant (1) subgingivally with Vector fluid polish (VU-H) and as three control quadrants, (2) with only supragingival polishing (PO-H), (3) with hand instruments (HI-H) performed by a hygienist and (4) with hand instruments (HI-D) performed by a dentist. At baseline, 3 and 6 months after treatment, pocket depths and attachment levels (ALs) were measured and bleeding on probing (BOP) was recorded.

RESULTS

At 6-month evaluation, all groups showed an improvement in clinical parameters. No statistically significant differences in any of the investigated parameters could be observed between the Vector group and the hand scaling groups, or when comparing the results of the two different operators.

CONCLUSION

This study demonstrates that Vector treatment with polishing fluid was able to reduce pocket depths and the prevalence of BOP and improve clinical AL in a similar way as scaling with curettes.

Comparative Study of Ultrasonic Instrumentation for the Non-Surgical Treatment of Interproximal and Non-Interproximal Furcation Involvements

BACKGROUND

The aim of this clinical trial was to compare the outcome of non-surgical treatment of interproximal and non-interproximal Class II furcation involvements.

METHODS

Thirty-eight patients presenting at least one Class II furcation involvement that bled on probing with a probing depth (PD) > or = 5 mm were recruited. Furcation involvements were grouped as either buccal and lingual furcation involvements (BLFI) or interproximal furcation involvements (IFI). The following clinical outcomes were evaluated: visible plaque index, bleeding on probing (BOP), position of the gingival margin, relative attachment level (RAL), PD, and relative horizontal attachment level (RHAL). N-benzoyl-l-arginine-p-nitroanilide (BAPNA) testing was used to analyze trypsin-like activity in dental biofilm. All parameters were evaluated at baseline and 1, 3, and 6 months after non-surgical subgingival instrumentation.

RESULTS

Six months after treatment, both groups had similar means of RAL and RHAL gain (P >0.05). These variables were 1.22 and 1.07 mm in the IFI group and 1.38 and 1.20 mm in the BLFI group, respectively. The PD reduction was significantly greater in the BLFI group than in the IFI group (2.59 and 2.11 mm, respectively; P <0.05). The BLFI group presented fewer sites with PD > or = 5 mm than the IFI group at all post-treatment periods. At 6 months, the BAPNA test showed that only the BLFI group had values significantly different from baseline. This means that the BLFI group had significantly lower BAPNA values compared to the IFI group at 6 months.

CONCLUSION

Buccal and lingual Class II furcation involvements respond better to non-surgical therapy compared to interproximal Class II furcation involvements.

Influence of fluorescence-controlled Er:YAG laser radiation, the Vectortm system and hand instruments on periodontally diseased root surfaces in vivo

OBJECTIVES

The aim of the present study was to evaluate the effects of fluorescence-controlled Er:YAG laser radiation, an ultrasonic device or hand instruments on periodontally diseased root surfaces in vivo.

MATERIAL AND METHODS

Seventy-two single-rooted teeth (n=12 patients) were randomly treated in vivo by a single course of subgingival instrumentation using (1-3) an Er:YAG laser (ERL1: 100 mJ; ERL2: 120 mJ; ERL3: 140 mJ; 10 Hz), or (4) the Vector ultrasonic system (VUS) or (5) hand instruments (SRP). Untreated teeth served as control (UC). Areas of residual subgingival calculus (RSC) and depth of root surface alterations were assessed histo-/morphometrically.

RESULTS

Highest values of RSC areas (%) were observed in the SRP group (12.5+/-6.9). ERL(1-3) (7.8+/-5.8, 8.6+/-4.5, 6.2+/-3.9, respectively) revealed significantly lower RSC areas than SRP. VUS (2.4+/-1.8) exhibited significantly lower RSC areas than SRP and ERL(1, 2). Specimens treated with SRP revealed conspicuous root surface damage, while specimens treated with ERL(1-3) and VUS exhibited a homogeneous and smooth appearance.

CONCLUSION

Within the limits of the present study, it may be concluded that ERL and VUS enabled (i) a more effective removal of subgingival calculus and (ii) a predictable root surface preservation in comparison with SRP.

A new system to detect residual subgingival calculus: in vitro detection limits

AIM

We recently introduced an experimental surface detection system based on a conventional dental ultrasonic scaler. This device automatically discriminates cementum and dental calculus, which is the prerequisite for complete and thorough calculus removal. In the present study, the detection limits of this device were tested in vitro.

MATERIAL AND METHODS

From 50 extracted teeth, subgingival calculus was gradually removed using a Gracey curette. During this stepwise procedure, detection properties of the surface detection system were continuously monitored and systematically verified until the system stopped discriminating calculus from the root surface. By measuring the diameter, circumference and area of the smallest, yet recognizable deposit, and of the no longer recognizable deposit, the cut-off point of the discriminative capability of the detection device was determined.

RESULTS

The cut-off points for the correct classification of residual deposits averaged on a diameter of 219 microm, an area of 21,600 microm2, and a circumference of 748 microm. This means a sensitivity of 73% and a specificity of 80% in this critical area.

CONCLUSIONS

This calculus detection system was able to detect small deposits. In clinical practice, this device may support dentists in deciding whether to stop or to continue the debridement.

Periodontal treatment with an Er:YAG laser compared to ultrasonic instrumentation: a pilot study

BACKGROUND

The aim of the present study was to compare the effectiveness of an Er:YAG laser to that of ultrasonic scaling for non-surgical periodontal treatment.

METHODS

Twenty patients with moderate to advanced periodontal disease were randomly treated in a split-mouth design with a single episode of subgingival debridement using either an Er:YAG laser device (160 mJ/pulse, 10 Hz) combined with a calculus detection system with fluorescence induced by 655 nm InGaAsP diode laser radiation (ERL), or an ultrasonic instrument (UI). Clinical assessments of full-mouth plaque score (FMPS), bleeding on probing (BOP), probing depth (PD), gingival recession (GR), and clinical attachment level (CAL) were made at baseline and at 3 and 6 months following therapy.

RESULTS

No differences in any of the investigated parameters were observed at baseline between the two groups. The mean value of BOP decreased in the ERL group from 40% at baseline to 17% after 6 months (P<0.0001) and in the UI group from 46% at baseline to 15% after 6 months (P<0.0001). The sites treated with ERL demonstrated mean CAL gain of 1.48 +/- 0.73 mm (P<0.001) and of 1.11 +/- 0.59 mm (P<0.001) at 3 and 6 months, respectively. The sites treated with UI demonstrated mean CAL gain of 1.53 +/- 0.67 mm (P<0.001) and of 1.11 +/- 0.46 mm (P<0.001) at 3 and 6 months, respectively. No statistically significant differences were observed between the groups (P>0.05).

CONCLUSION

Within the limits of the present study, it can be concluded that both therapies led to significant improvements of the investigated clinical parameters.

Morphometric Analysis of the Furcation Anatomy of Mandibular Molars

BACKGROUND

Successful treatment of molar furcation defects remains a challenge in clinical practice. Knowledge of anatomic factors facilitates predictable management of furcation involvement lesions. The degree of success in managing furcation involvement is inversely related to the horizontal probing depth. The depth of the horizontal component of attachment loss can vary depending on the external tooth-surface reference points used. However, the anatomical factors affecting horizontal component of attachment loss have not been previously assessed. Therefore, this study determined the bucco-lingual measurements of the cemento-enamel junction and the mesial and distal roots and at the level of root separation.

METHODS

One hundred extracted permanent human mandibular first (N = 50) and second (N = 50) molars were studied. Four horizontal bucco-lingual widths were measured with calibrated calipers: 1) furcation entrance/roof (FE); 2) cemento-enamel junction level (CEJ); 3) mesial root width (MRW); and 4) distal root width (DRW).

RESULTS

The mean widths at FE, CEJ, MRW, and DRW were, respectively, 5.53 +/- 0.45 mm, 8.71 +/- 0.54 mm, 8.57 +/- 0.54 mm, and 7.97 +/- 0.65 mm in the first molars and 5.61 +/- 0.65 mm, 8.40 +/- 0.65 mm, 7.95 +/- 0.88 mm, and 7.16 +/- 0.84 mm in the second molars. Analysis of variance revealed significant differences between FE and the other variables tested. The results showed that the bucco-lingual width of the furcation roof is considerably shorter than the MRW and DRW. The difference in the mean bucco-lingual dimension between FE and the other measurements occurred in all teeth evaluated and varied between 0.7 and 4.30 mm.

CONCLUSIONS

Our findings demonstrate that clinical measurements of horizontal probing depth that use the external surfaces of roots as reference points overestimate the true anatomical component of furcation involvement in mandibular molars. Conversely, positive treatment outcomes in these teeth may be underestimated. This has implications not only for clinical practice but also for clinical research studies evaluating treatment outcomes.

Non-surgical periodontal treatment with a new ultrasonic device (Vectortm-ultrasonic system) or hand instruments. A prospective, controlled clinical study

OBJECTIVES

The aim of this prospective, randomized, controlled clinical study was to compare the effectiveness of a newly developed ultrasonic device to that of scaling and root planing for non-surgical periodontal treatment.

MATERIAL AND METHODS

Thirty-eight patients with moderate to advanced chronic periodontal disease were treated according to an "one-stage procedure" with either a newly developed ultrasonic device (VUS) (Vector-ultrasonic system) or scaling and root planing (SRP) using hand instruments. Clinical assessments by plaque index (PlI), gingival index (GI), bleeding on probing (BOP), probing depth (PD), gingival recession (GR), and clinical attachment level (CAL) were made prior to and at 6 months after treatment. Differences in clinical parameters were analyzed using the Wilcoxon signed ranks test and Mann and Whitney U-test.

RESULTS

No differences in any of the investigated parameters were observed at baseline between the two groups. The mean value of BOP decreased in the VUS group from 32% at baseline to 20% after 6 months (p<0.001) and in the SRP group from 30% at baseline to 18% after 6 months (p<0.001). The results have shown that at moderately deep sites (initial PD 4-5 mm) mean CAL changed in the test group from 4.6+/-1.2 to 4.2+/-1.6 mm (p< 0.001) and in the control group from 4.8+/-1.3 to 4.4+/-1.5 mm (p<0.001). At deep sites (initial PD>6 mm) mean CAL changed in the test group from 8.5+/-1.9 to 7.9+/-2.4 mm (p<0.001) and in the control group from 7.9+/-1.6 to 7.2+/-2.2 mm (p<0.001). No statistically significant differences in any of the investigated parameters were found between the two groups.

CONCLUSION

Non-surgical periodontal therapy with the tested ultrasonic device may lead to clinical improvements comparable to those obtained with conventional hand instruments.

Comparative effectiveness of hand and ultrasonic instrumentations in root surface planing in vitro

BACKGROUND/AIMS

A variety of techniques are employed for planing and scaling of the superficial root surfaces, of which hand and ultrasonic instrumentations have been preferentially used in routine periodontics clinics. This study was undertaken to compare the effectiveness of ultrasonic scalers and hand curettes in facilitating fibroblast attachment to the scaled root surfaces.

MATERIALS AND METHODS

Sixteen patients with periodontally involved teeth and nine subjects without periodontal diseases (control subjects) were selected. Two single-rooted teeth were extracted from each subject. Mesial and distal surfaces of teeth were selected in treated and untreated groups, respectively. The mesial surface of each tooth was randomly chosen to be treated either by hand curettes or ultrasonic instrumentation. The degree of cell attachment on the root surfaces of treated and untreated groups from control subjects and patients was then determined by the use of a gingival fibroblast line established and employed at early passages. The attachment and proliferation of gingival fibroblasts on the root surfaces were evaluated using neutral red assay and scanning electron microscopy (SEM).

RESULTS

Fibroblast survival and proliferation on the surfaces of untreated periodontally involved roots were found to be significantly lower compared with control untreated surfaces (p<0.0001) or treated surfaces from patients (p<0.0001). No significant difference, however, was observed between root surfaces treated either by hand curettes or ultrasonic scalers.

CONCLUSION

These results indicate the beneficial effectiveness of both techniques in root treatment and planing.

Comparative clinical responses related to the use of various periodontal instrumentation

AIM

The aim of this study was to evaluate in vivo the effectiveness of scaling and root planing of a power-driven mechanism compared with hand instruments and ultrasonic insert alone with a split-mouth design after 3 and 6 months.

METHODS

Healing events after initial periodontal therapy were investigated in 20 patients with moderate-to-severe adult periodontitis. Plaque index (PlI), bleeding on probing (PBI), probing pocket depth (PPD), probing attachment level (PAL) and number of moderate and deep pockets (NMP, NDP) were recorded at baseline and 3 and 6 months after treatment. Oral hygiene instruction was provided for each patient. Randomly assigned quadrants per patient were scaled and root planed with hand instrumentation (curettes, hoes and files), with reciprocating power-driven instruments, with ultrasonic scaler alone and with the combined use of ultrasonic scaler and power-driven inserts. The Friedman test was applied to test the significance of difference between the various methods of root instrumentation. Repeated measures of analysis of variance (manova) were used to analyse the time effect on the different treatments.

RESULTS

At the 6-month evaluation, all groups in the scaling and root planing treatment presented with an improvement in the measured clinical parameters, as compared with baseline. No statistical differences (p>0.05) were observed in the assessed periodontal indices among the study sites between the four groups for either treatment.

CONCLUSIONS

Under our experimental conditions, this clinical study demonstrates that mechanized root planing with power-driven instruments, as effective as the usual procedures (hand and sonic instruments), represents a satisfactory and alternative means of nonsurgical root therapy.

Local Anti-Infective Therapy: Mechanical and Physical Approaches. A Systematic Review

BACKGROUND

Although mechanical non-surgical therapy (scaling and root planing) is the most common means of initial treatment of periodontal diseases, the relative clinical efficacy of various methods, including manual versus machine-driven, with or without adjunctive agents, has not been determined.

RATIONALE

This systematic review analyzes the literature in an effort to identify the most effective therapies, based on both clinical and patient-centered outcomes.

FOCUSED QUESTION

In patients with periodontitis, what is the effect of mechanically-driven instrumentation (e.g., power-driven) and/or subgingival irrigation with and without manual instrumentation compared to manual instrumentation alone?

SEARCH PROTOCOL

Two investigators examined MEDLINE and the Cochrane Oral Health Group specialized registry for clinical trials published in English. Hand searches were performed of the International Journal of Periodontics & Restorative Dentistry, Journal of Clinical Periodontology, Journal of Periodontology, and Journal of Periodontal Research. Searches were performed for articles published through April 2002. Editors of these journals were asked to provide information on articles currently under review. In addition, an electronic discussion group on periodontal diseases and treatment was contacted, as were manufacturers of manual and mechanical instruments and of adjunctive agents.

SELECTION CRITERIA

INCLUSION CRITERIA

Only randomized clinical trials, cohort studies, or case-control studies at least 3 months long were included. All studies had to compare manual instrumentation (MI; scaling and root planing [SRP]) alone with some other form of non-surgical therapy. These included MI versus mechanically-driven instruments (MDI) alone; MI versus MI plus MDI; MI versus MDI plus an agent (e.g., chlorhexidine); and MI versus subgingival irrigation (SGI) delivered in conjunction with MI or MDI.

EXCLUSION CRITERIA

Studies not meeting the inclusion criteria or those treating periodontal diseases as a manifestation or complication of some other disease or disorder were not included.

DATA COLLECTION AND ANALYSIS

Probing depth, clinical attachment level, bleeding on probing, and gingival recession were the primary outcomes. Because of the heterogeneity of the patient populations, treatments, and outcome measures, meta-analysis was not appropriate. Only in-study data were compared. Four of the studies required extrapolating data from figures and graphs, resulting in questionable accuracy.

MAIN RESULTS

1. Nine studies, representing a study population of 129, were included in the review. 2. Five studies compared MI with MDI alone. The other 4 compared MI alone to MI plus SGI or subgingival tissue treatment. 3. There was comparable efficacy between MI and MDI when treating single-rooted teeth. 4. The use of SGI or subgingival tissue treatment as an adjunct to MI provided no additional benefit compared to MI alone. 5. Findings reported in the review must be interpreted with considerable caution, as lack of study heterogeneity made meta-analysis unfeasible and the need to extrapolate outcomes values from graphs and figures may have resulted in some inaccuracy.

REVIEWERS' CONCLUSIONS

1. Manual and mechanically-driven instrumentation appears comparable in affecting improved clinical outcomes. 2. Instrumentation time for MI and MDI were similar, except for 1 study in which MDI was significantly shorter. 3. Adjunctive SGI plus MI and subgingival tissue treatment result in similar clinical outcomes when compared to MI alone. 4. If study data are to be effectively and analytically combined to facilitate meaningful comparisons of treatment outcomes, detailed and standardized study designs must be developed and used consistently in clinical trials.

Effectiveness of a combination of platelet-rich plasma, bovine porous bone mineral and guided tissue regeneration in the treatment of mandibular grade II molar furcations in humans

OBJECTIVE

A combination of platelet-rich plasma (PRP), bovine porous bone mineral (BPBM) and guided tissue regeneration (GTR) has been shown to be effective as regenerative treatment for intrabony periodontal defects. The purpose of this study was to evaluate the effectiveness of PRP, BPBM and GTR used in combination as regenerative treatment for grade II molar furcation defects in humans.

MATERIAL AND METHODS

Using a split-mouth design, a total of 52 grade II mandibular molar furcation defects were treated either with PRP/BPBM/GTR (experimental group, n=26) or with an open flap debridement (control group, n=26). The primary outcomes evaluated in this study included changes in pocket depth, attachment level and re-entry bone levels (horizontal and vertical) between baseline and 6 months postoperatively.

RESULTS

The results showed that the experimental group presented with significantly greater pocket reduction (4.07+/-0.33 mm for experimental and 2.49+/-0.38 mm for control sites), gain in clinical attachment (3.29 +/- 0.42 mm for experimental and 1.68+/-0.31 mm for control sites), vertical defect fill (2.56+/- 0.36 mm for experimental and -0.19+/-0.02 for control sites) and horizontal defect fill (2.28+/-0.33 mm for experimental and 0.08+/-0.02 mm for control sites) than the control group.

CONCLUSIONS

It was concluded that the PRP/BPBM/GTR combined technique is an effective modality of regenerative treatment for mandibular grade II furcation defects. Further studies are necessary to elucidate the role played by each component of the combined therapy in achieving these results.

A systematic review of efficacy of machine-driven and manual subgingival debridement in the treatment of chronic periodontitis

OBJECTIVES

The purpose of this systematic review was to determine the efficacy of machine-driven compared with manual subgingival debridement in the treatment of periodontitis.

BACKGROUND

Mechanical debridement of the periodontal pocket plays a pivotal role in the treatment of periodontitis.

METHODS

A literature search for controlled clinical trials with at least 6 months' follow-up comparing machine-driven instruments with hand instruments for the treatment of chronic periodontitis was performed up to April 2001. Screening of titles and abstracts as well as data extraction was conducted independently by two reviewers (J.T. & T.F.F.). As primary outcome variable, the prevention of tooth loss was used; secondary outcome variables were the prevention of disease progression, the resolution of anatomical defects and the resolution of gingival inflammation. Efficiency was assessed by mean time needed to treat one tooth.

RESULTS

From a total of 419 abstracts, 27 articles were included for the review. The weighted kappa score for agreement between the two reviewers was 0.77, 95% CI: 0.65-0.89, indicating substantial agreement. No study reported on the selected primary outcome variables. Using clinical attachment gain, probing pocket depth reduction or bleeding on probing reduction as outcome variables, there appeared to be no differences between ultrasonic/sonic and manual debridement. No major differences in the frequency or severity of adverse effects were found. However no meta-analysis could be performed on any of the previously mentioned parameters. Ultrasonic/sonic debridement was found to take significantly less time, i.e. 36.6%, than debridement using hand instruments (P = 0.0002, 95% CI of the standardized effect estimate: 0.39-1.37, heterogeneity P = 0.77).

CONCLUSIONS

With respect to clinical outcome measures, the available data do not indicate a difference between ultrasonic/sonic and manual debridement in the treatment of chronic periodontitis for single-rooted teeth; however, the evidence for this is not very strong. In addition, ultrasonic/sonic subgingival debridement requires less time than hand instrumentation. Further research is needed to assess the efficacy of machine-driven debridement on multirooted teeth and clinical outcome variables having tangible benefit to the patients should be used.

Clinical significance of non-surgical periodontal therapy: an evidence-based perspective of scaling and root planing

Analysis of Egyptian hieroglyphics and medical papyri indicate that non-surgical periodontal treatment was common 3000-4000 years ago. Even today, scaling and root planing (SRP) remains an essential part of successful periodontal therapy. The collective evidence from numerous clinical trials reveals a consistency of clinical response in the treatment of chronic periodontitis by SRP using manual, sonic, or ultrasonic instrumentation. Thus, SRP remains the 'gold standard' to which more recently developed therapeutic modalities must be compared. Inherent to the clinical evaluation of SRP are such concerns as manual versus sonic and ultrasonic instrumentation, control of sub-gingival bacterial populations, removal of calculus, root smoothness and changes in various clinical parameters, e.g. probing depth, attachment levels, bleeding on probing and gingival inflammation. Lastly, an abbreviated discussion is presented on a relatively new paradigm of complete mouth 'disinfection' in a compressed time-frame that includes SRP as a significant component of the treatment regimen.

A comparative in vitro study of a magnetostrictive and a piezoelectric ultrasonic scaling instrument

BACKGROUND

The effects of magnetostrictive ultrasonic instruments and piezoelectric ultrasonic instruments on tooth surfaces seem to differ with regards to root debridement.

AIM

The purpose of this study was to compare a magnetostrictive ultrasonic scaling instrument with a piezoelectric ultrasonic scaling instrument and a hand curette regarding time taken, calculus removal, tooth surface roughness (Ra), and SEM examination before and after instrumentation.

METHODS

30 extracted human teeth with subgingival calculus were assigned to one of three treatment groups (n=10). The working force was standardised for both ultrasonic instruments at 200 g and for the curette at 500 g.

RESULTS

The results revealed that the time needed for instrumentation was 126.1+/-38.2 s for the curette, significantly more than for the piezoelectric ultrasonic instrument (74.1+/-27.6 s; p<0.05) and 104.9+/-25.4 s for the magnetostrictive ultrasonic instrument. Remaining calculus was similar for all three groups. The end Ra values were significantly worse for the piezoelectric instrument (2.02+/-0.41; p<0.05) compared to 1.42+/-0.48 for the curette and 1.36+/-0.41 for the magnetostrictive instrument. The SEM examination revealed the smoothest surfaces but, subjectively, the most tooth substance loss after the curette, followed by the magnetostrictive instrument, with the least substance loss, and then the piezoelectric instrument, with medium substance loss.

CONCLUSION

The piezoelectric ultrasonic scaler was more efficient than the magnetostrictive ultrasonic scaler in removing calculus but left the instrumented tooth surface rougher.

Position paper: sonic and ultrasonic scalers in periodontics. Research, Science and Therapy Committee of the American Academy of Periodontology

Ultrasonic and sonic scalers appear to attain similar results as hand instruments for removing plaque, calculus, and endotoxin. Ultrasonic scalers used at medium power seem to produce less root surface damage than hand or sonic scalers. Due to instrument width, furcations may be more accessible using ultrasonic or sonic scalers than manual scalers. It is not clear whether root surface roughness is more or less pronounced following power-driven scalers or manual scalers. It is also unclear if root surface roughness affects long-term wound healing. Periodontal scaling and root planing includes thorough calculus removal, but complete cementum removal should not be a goal of periodontal therapy. Studies have established that endotoxin is weakly adsorbed to the root surface, and can be easily removed with light, overlapping strokes with an ultrasonic scaler. A significant disadvantage of power-driven scalers is the production of contaminated aerosols. Because ultrasonics and sonics produce aerosols, additional care is required to achieve and maintain good infection control when incorporating these instrumentation techniques into dental practice. Preliminary evidence suggests that the addition of certain antimicrobials to the lavage during ultrasonic instrumentation may be of minimal clinical benefit. However, more randomized controlled clinical trials need to be conducted over longer periods of time to better understand the long-term benefits of ultrasonic and sonic debridement.

Guided tissue regeneration in Class II furcation involved maxillary molars: a controlled study of 8 split-mouth cases

The purpose of this study was to clinically evaluate the effectiveness of polytetrafluoroethylene membranes in the healing of interproximal Class II furcation defects in maxillary molars using a surgical treatment technique based on the principles of guided tissue regeneration. Eight subjects with similar bilateral Class II furcation lesions on the mesial aspect of maxillary first molars participated in this study. Patients received initial therapy consisting of oral hygiene instructions, scaling and root planing, and occlusal adjustment if necessary. Clinical parameters evaluated included plaque index, sulcular bleeding index, probing depth, attachment level, gingival recession, and open horizontal and vertical furcation fill. An acrylic occlusal stent was used to assure reproducibility of measurements. Experimental sites received a polytetrafluoroethylene membrane following surgical exposure of the furcation. Control sites were treated in the exact same manner but without a membrane. Membranes were removed at 6 weeks after the first surgery. Reentry surgeries were performed at 9 months. Postsurgical results showed a significant improvement in probing depth, attachment level, and open horizontal furcation fill for both groups when compared to baseline values, with experimental sites performing significantly better than controls. Control sites showed a slight loss in open vertical furcation fill while experimental sites remained unchanged. This study suggests that guided tissue regeneration using polytetrafluoroethylene membranes is of some but limited value in the treatment of maxillary molar interpoximal Class II furcation lesions.

Evaluation of periosteal membranes and coronally positioned flaps in the treatment of Class II furcation defects: a comparative clinical study in humans

The purpose of this study was to compare the clinical effectiveness of connective tissue grafts including periosteum used as a mechanical barrier for guided periodontal tissue regeneration and coronally positioned flaps in the treatment of Class II furcation defects. A total of 28 furcation defects were treated; 14 received a periosteal barrier and 14 received a coronally positioned flap. Reentry surgeries were performed at 6 months. No statistically significant differences were found preoperatively between the two treatment groups with respect to clinical parameters and osseous measurements. Postsurgically, both treatment modalities resulted in a significant decrease in probing depth and a significant gain in clinical attachment, but the differences observed were not statistically significant. The periosteal barrier group presented with a significantly better gain in vertical components of the alveolar bone (1.93 +/- 0.15 mm and 0.20 +/- 0.26 mm for periosteal barrier and coronally positioned flap groups, respectively; P < or = 0.001) and horizontal components of the alveolar bone (1.60 +/- 0.21 mm and 0.13 +/- 0.90 mm for periosteal barrier and coronally positioned flap groups, respectively; P < or = 0.001). The results of this trial indicate that similar clinical resolution of Class II furcation defects can be obtained with periosteal barriers and coronally positioned flaps. Periosteal barriers, however, are a better treatment alternative in achieving bone fill of the furcation area.

Comparative in vitro effectiveness of closed root debridement with fine instruments on specific areas of mandibular first molar furcations. II. Furcation area

The purpose of this study was to demonstrate the extent of deposits removed from within the furcation area of mandibular first molars following the use of curets with a modified blade and slim ultrasonic inserts in an in vitro model simulating a closed root debridement approach to furcation treatment. The furcation areas of 100 artificial mandibular first molars were uniformly coated with black model paint. The molars were fixed into a custom acrylic model, maintained in a firm position with modified occlusal splints, and the roots covered with a heavy rubber dam. The model was set in a mannequin and mounted on a dental chair recreating a clinical situation. Fifty molars (25 right, 25 left) were instrumented with the experimental curets and an equivalent number of molars with the ultrasonic inserts. An experienced dental hygienist completed all the instrumentation, spending 4 minutes on each molar. The molars were sectioned buccolingually from the crown apically to separate the roots, and areas in the internal surface of mesial and distal roots were analyzed to determine the percentage of deposits remaining using a computerized imaging routine system. A 2-factor analysis of variance was conducted to test for differences between both types of instruments. The curets produced furcation root surfaces with significantly less percentage of residual deposits than the ultrasonic inserts (P < 0.01). This study indicates the potential value of small bladed curets in debriding involved furcations during initial therapy and supportive periodontal therapy. The current findings should be corroborated in a clinical study.

Comparative in vitro effectiveness of closed root debridement with fine instruments on specific areas of mandibular first molar furcations. I. Root trunk and furcation entrance

The purpose of this study was to compare curets with a small blade to slim ultrasonic inserts on their efficacy in removing artificial deposits from the root trunk and furcation entrance areas of mandibular molars using an in vitro model simulating a clinically closed root debridement approach. The study was conducted on 100 artificial mandibular first molars (50 right side and 50 left side) with anatomical roots. Root trunks, furcation entrances, and furcation areas of each molar were colored by a coat of black model paint. The teeth were fixed in a custom acrylic model and maintained in a firm position by modified acrylic occlusal splints. The root areas were covered with a heavy rubber dam imitating gingival tissue. The model was attached to a mannequin and mounted on a dental chair. Fifty molars (25 right, 25 left) were instrumented with the experimental curets and an equivalent number of molars with the ultrasonic inserts. The instrumentation was carried out by one experienced operator, spending 4 minutes on each molar. The instrumented areas were individually analyzed to determine the percentage of deposits remaining, using a computerized imaging routine system. One-way analysis of variance was conducted to test for differences between both types of instruments. Results revealed that the curets were significantly more efficient (P < 0.01) than the ultrasonic inserts in removing paint from both root trunks and furcation entrances. These findings should be corroborated in a clinical study to determine the potential value of the instruments tested during initial therapy or supportive care of involved mandibular furcations.

The bactericidal effects of dental ultrasound on Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis. An in vitro investigation

This study investigated the possible bactericidal acoustic effects of the dental ultrasonic scaler. Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis suspensions, were subjected to the vibrations of a Cavitron P1 insert for 2.5 and 5.0 min in an acoustically-simulated pocket model and the survivors enumerated. The extent of any cavitation occurring within the pocket model to which the statistically significant bactericidal activity observed might be attributed, was determined by 'sonoluminescence', which was then investigated by photomultiplication techniques. However, these failed to detect any sonoluminescence within the pocket space and, moreover, the necessary deflection of the water coolant away from the insert tip, to avoid flooding of the experimental pocket, proved to result in temperatures of 47.6 degrees C and 52.3 degrees C at the respective time intervals, and thereby constituted an alternative possible bactericidal mechanism. Examination of the effects of such temperature changes on the target bacteria then revealed statistically significant differences in the viable counts of both microorganisms after 5.0-min periods, and as such were comparable to those previously detected in relation to the pocket model. Whilst it must be presumed that the bacteriolytic effect observed in the main investigation was due to the incidental temperature changes, in the absence of acoustic cavitation the influence of any associated acoustic microstreaming cannot be discounted. Further investigations to assess the bactericidal potential of acoustic phenomena using a modified experimental to exclude any hyperthermic effects are therefore necessary.

Microbiological response to mechanical treatment in combination with adjunctive therapy. A review of the literature

The recognition of the microbial origin and the specificity of periodontal infections has resulted in the development of several adjunctive therapies (antibiotics and/or antiseptics) to scaling and root planing in the treatment of chronic adult periodontitis. This article aims to review the "additional" effect of a subgingival irrigation with chlorhexidine, or a local or systemic application of tetracycline or metronidazole, performed in combination with a single course of scaling and root planing in patients with chronic adult periodontitis. All treatment modalities are compared with scaling and root planing, based on their impact on: the probing depth (PD); total number of colony forming units per ml (CFU/ml); the proportions and/or the detection-frequency of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, and Prevotella intermedia; and/or on the percentages of cocci, spirochetes, motile, and other micro-organisms on dark field microscopy examination. All treatment modalities, including scaling and root planing without additional chemical therapy, resulted in significant reductions in the probing depth and the proportions of periodontopathogens, at least during the first 8 weeks post-therapy. However in comparison to a single course of scaling and root planing, the supplementary effect of adjunctive therapies seems to be limited. In general, only the irrigation with chlorhexidine 2%, the local application of minocycline, and the systemic use of metronidazole (in case of large proportions of spirochetes) or doxycycline (in case of large proportions of A. actinomycetemcomitans) seem to result in a prolonged supplementary effect when compared to scaling and root planing. Therefore, the use of antibiotics on a routine basis, especially in a systemic way, in the treatment of chronic adult periodontitis, can no longer be advocated, considering the increasing danger for the development of microbial resistance.

A comparative study of a surgical method and scaling and root planing using the Odontoson

This investigation compared a traditional periodontal surgical method with a non-surgical treatment of scaling and root planing by an ultrasonic device (Odontoson M) using irrigation with an iodised solution. 8 adult patients with periodontal disease were each treated at 2 randomly chosen quadrants by a Widman flap type surgical technique, and the remaining non-surgically. The patients then attended bi-monthly oral hygiene sessions over a period of 1 year. At that stage, clinical evaluation revealed that the Odontoson M plus an ionized irrigant solution achieved a statistically comparable outcome to that of surgical treatment, even in the pockets initially up to 7 mm in depth.

Rationale of mechanical plaque control

Patients who have received extensive periodontal treatment also demonstrate a high susceptibility to periodontal disease. Maintenance of periodontal health following therapy includes a lifelong supportive care consisting of daily removal of the microbial plaque by the patient, supplemented by professional care in an individually designed programme. Mechanical supragingival plaque control by self care is of utmost importance. The goal is to create a positive attitude by information and motivation to give the patient knowledge and confidence. The patient should be advised to use appropriate aids and technique. A soft brush, an interspace brush, interdental tooth brushes or tooth picks are recommended in periodontal patients. Professional tooth cleaning involves removal of supragingival plaque from all tooth surfaces using mechanically driven instruments and fluoride prophy paste and, when indicated, removal of calculus and subgingival plaque. Disclosing solution is used to visualize the plaque to the patient and to the clinician in order to reinforce instruction in oral hygiene. Oral hygiene measures alone seem to have limited effect on subgingival microflora in cases of severe disease. In shallow and moderately deep pockets a good plaque control can change the subgingival flora towards a more "healthy" composition. Subgingival plaque removal is performed with hand- and/or ultrasonic instruments. Cracks within the cementum, grooves, fissures, resorption lacunae, furcations may create difficulties in cleaning the root surface. Ultrasonic instrumentation has a beneficial effect in creating a smooth surface without extensive removal of cementum. Besides, the cavitational activity contributes to plaque removal which makes the instrument further suitable during maintenance therapy. The result of the debridement is assessed on the healing response in the tissues. The frequency of maintenance visits must be given on an individual basis according to the needs of every special patient. The visit includes plaque evaluation (disclosion), oral hygiene instruction, probing depth measurements, registration of bleeding on probing, scaling (plaque removal) if indicated, tooth polishing, fluoride application and radiographs if indicated. The goal is to identify and treat signs of recurrence of periodontal disease in order to prevent further loss of attachment.

The topography of the furcation entrance in Chinese molars. Furcation entrance dimensions

The purpose of the present study was to document the furcation entrance dimensions (FEDs) of the maxillary and mandibular 1st and 2nd molars and relate them to the choice of periodontal therapy. Study samples consisted of 89 maxillary molars (49 1st and 40 2nd molars) and 93 mandibular molars (50 1st and 43 2nd molars). All the FEDs of the molars were examined and measured under a stereomicroscope at 2.5 x equipped with a Bioscan OPTIMAS Image Analyzer (BOIA). The results may be summarized as follows. (1) The mean FEDs in the buccal, distal and mesial furcations of maxillary 1st and 2nd molars were 0.74 mm, 0.99 mm and 1.04 mm in the 1st molars, and 0.63 mm, 0.67 mm, 0.90 mm in the 2nd molars, respectively. In the buccal and lingual furcations of mandibular 1st and 2nd molars, they measured 0.88 mm and 0.81 mm, and 0.73 mm and 0.71 mm, respectively. (2) The %s of FEDs of 0.56 mm or less (the tip width of a Cavitron tip being 0.56 mm) in the buccal, distal and mesial furcations of maxillary 1st and 2nd molars, accounted for 32%, 8% and 6% of 1st molars, and 40%, 40% and 18% of 2nd molars. In the buccal and lingual areas of mandibular 1st and 2nd molars, they accounted for 16% and 26%, and 35% and 33% of the furcations, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

The periodontally-involved root surface

Recent years have seen much research on the periodontally-involved root surface. Many of these studies have produced results which suggest that plaque contaminants of the root surface are only superficially placed, and capable of being removed by gentle means. Further research has attested to the difficulties in rendering periodontally-involved root surfaces free of calculus deposits by instrumentation, yet clinical studies show that periodontal disease can be managed by root planing. It is concluded that root surface debridement is best assessed on the basis of the healing response and that it should aim to disrupt plaque on and remove plaque from the periodontally-involved root surface rather than to remove part of the root surface itself.

Efficacy of 5 machining instruments in scaling of molar furcations

The scaling efficacy of machining instruments was studied in the furcations of 100 extracted molars. The molars were divided into 5 groups with similar furcation anatomy, painted with artificial calculus, partly submerged in stone blocks, and the furcation entrances covered with a heavy rubber dam material. Ten mandibular and 10 maxillary molars were scaled by an experienced operator with each of the following instruments/inserts: ultrasonic instrument with either a prototype ball point insert or with a new pointed insert; ultrasonic instrument with a ball point insert; reciprocating hand-piece with new inserts for furcations; and a sonic scaler with a universal insert. The molar groups were coded and graded in a stereomicroscope by 2 independent examiners, and the rankings were tested with the Kruskal-Wallis test and the multiple comparisons between treatments test. The results revealed statistically significant differences between the instruments, as well as between different topographical areas of the furcations. The sonic scaler with a universal insert and the ultrasonic instrument with ball point inserts were significantly more efficient (P < 0.05) than the reciprocating handpiece with inserts in most of the areas studied. For mandibular molars, significantly better results (P < 0.05) were obtained for lingual furcation entrances than for furcation roofs. For maxillary molars, significantly better results (P < 0.05) were obtained for distal and buccal entrance areas than for furcation roofs and inside of mesial roots. The present study may give some guidance to the practitioner in choosing machining instruments for furcation cleaning as well as identifying the most difficult topographical areas to instrument.

Effects of ultrasonic and sonic scalers on dental plaque microflora in vitro and in vivo

The effects of ultrasonic and sonic scalers on the subgingival microflora were investigated in vitro and in vivo. In the in vitro investigation, 27 plaque samples collected from periodontal pockets were submitted to ultrasonic and sonic vibrations for 10, 30 and 60 s. Bacterial suspensions were examined by darkfield microscopy to detect qualitative changes and cultured to evaluate the total number of cultivable bacteria. Microscopic counts following both instrumentations showed a decrease in the proportions of spirochetes and motile rods and an increase in the % of coccoids and rods. The changes were directly related to the time-period of instrumentation. Comparison between both types of instrumentation showed significant differences and more pronounced changes were observed with the ultrasonic than the sonic scaler. Spirochetes and motile rods were reduced to approximately 0.1% after ultrasonic treatment versus 24.7% after sonic instrumentation. Cultural observations showed a marked increase in total number of colony-forming units following both treatments. The clinical investigation included 66 periodontal pockets which were instrumented subgingivally for 10 and 30 s with ultrasonic or sonic scalers. Qualitative changes were similar to those observed in vitro, i.e., reduction in spirochete and motile rod counts as well as the other morphotypes with an increase in coccoid cells. Total counts of bacteria were reduced following debridement. No difference in the microscopic or cultural data was found between ultrasonic and sonic instrumentation.