Accessibility of an ultrasonic furcation tip to furcation areas of mandibular first and second molars

The purpose of this study was to compare an ultrasonic furcation tip with an ultrasonic conventional tip and a hand scaler on accessibility to furcation areas of mandibular first and second molars. The study was conducted on 360 artificial molars that were replicated from 30 mandibular first molars and 30 second molars with silicone impression material and resin. The furcation areas of each molar were coated with red nail colour for artificial calculus. The root areas from the cement-enamel junction apically were covered with silicone rubber simulating gingival tissue. Then the models were instrumented on the buccal or lingual aspects by an experienced operator with each of the following instruments: an ultrasonic furcation tip, an ultrasonic conventional tip and a hand scaler. After instrumentation the percentage of the furcation area with residual artificial calculus was assessed using a computerised imaging system. Results showed that when the horizontal pocket depth was less than 2mm, all three instruments showed good accessibility. When the horizontal pocket depth was more than 2mm, the ultrasonic conventional tip and the hand scaler showed less removal of artificial calculus than the ultrasonic furcation tip (P < 0.01). Efficiency of the ultrasonic furcation tip was fairly satisfactory for the horizontal pocket up to the ridge of the furcation roof.     

Microscopic analysis of the effects of ultrasonic instrumentation on the root surface of molar furcations

Twenty molars, 10 from the maxilla and 10 from the mandible with furcation areas type II (Staffileno) were instrumented in their inter-radicular area with P10 instrument of Cavitron. It was established that the furcations of easier access instrumentation were the lingual o lower teeth and the buccal of the upper, and the most difficult accessibility were the distal of upper molars. The instrumentation can leave grooves or deformations, depending on the instrument to the area. It was concluded that ultrasonic instrument are useful removing supragingival calculus and bacterial plaque, and it must be limited to perform such procedures.     

In vitro effectiveness of a newly-designed ultrasonic scaler tip for furcation areas

This study was undertaken to perform an in vitro comparison of the accessibility and effectiveness of a newly-designed furcation tip for an ultrasonic system with conventional curets and ultrasonic scalers. The new furcation tip was spiral in shape with a spherical end. The study was conducted on three groups of 40 teeth, each comprising 20 maxillary and 20 mandibular molars. The furcation of each tooth was colored by black felt-tipped marker, after which the teeth were fixed into artificial jaw models. Each group was then instrumented by either the newly-designed furcation tip, a straight type ultrasonic scaler tip, or a Gracey curet. The teeth were photographed by a stereomicroscope from the dome surface of furcation, and the percentage of remaining colored area was calculated for each tooth. Replica models were also made and examined with scanning electron microscopy (SEM). The mean percentage of the remaining colored areas for each instrument was, for the maxillary molars and mandibular molars respectively, 15.1% and 16.7% with the newly-designed tip; 50.3% and 44.1% with the straight type ultrasonic scaler; and 61.1% and 39.5% with the Gracey curets. The newly-designed tip thus showed high levels of effectiveness and accessibility for furcation debridement. Although the SEM photographs showed that each instrument had affected the furcation surfaces in various degrees, the teeth instrumented by the newly-designed tip maintained relatively smoother surfaces. It was concluded that the newly-designed furcation tip was more effective than the straight type ultrasonic scaler or the Gracey curet in the debridement of furcation in vitro.     

Scaling and root planing efficacy in multirooted teeth

The effect of operator experience level and root surface access on instrumentation of multirooted teeth was investigated. Fifty molars designated for extraction were randomly distributed among four operators of two different experience levels for scaling and root planing with or without surgical access. Following treatment the teeth were extracted and scored in a blind manner for residual calculus. Teeth were sectioned to allow assessment of the furcal aspects. Results show that operators of both experience levels obtained calculus-free root surfaces significantly more often with flap access than with a non-surgical approach. Additionally, operators with more experience achieved calculus-free root surfaces significantly more often than operators of lesser experience with both an open and closed procedure. However, when furcation aspects alone were assessed, it was found that the more experienced operators obtained a calculus-free surface only 68% of the time with an open approach. Results suggest that, although both surgical access and a more experienced operator significantly enhance calculus removal in molars with furcation invasion, total calculus removal in furcations utilizing conventional instrumentation may be limited.     

Instrumentation of furcation with modified sonic sealer inserts A study on manikins (II)

Abstract. We developed a sonic sealer tip with an ellipsoid diamond-coated bud and contra-angulated shafts to overcome problems resulting from furcation anatomy. In this study, extracted molars were instrumented in a dummy model without any replicated soft tissues using 3 different instrumentation methods (i) curettes, (ii) diamond-coated sonic sealer tips with normal handle and (iii) diamond-coated sonic sealer tips in 2 handles with varying power levels. 15 extracted upper and lower molars were instrumented using each of the 3 instrumentation types. Following debridement, loss of substanee and % of furcation area instrumented were assessed. In both upper and lower molars, significantly more surface area was instrumented in one instrumentation run with diamond-coated tips than with curettes. Substance loss was greater with diamond-coated lips than with hand instruments. In conclusion, an effective debridement of the furcation roof seems only possible with odontoplasty. Clinical evaluation of this approach to root debridement is needed.     

The topography of the furcation entrance in Chinese molars

Abstract 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 × 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 1 st 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. (3) The %s of FEDs of 0.75 mm or less (the width of curettes being 0.75–1.0 mm) in the buccal, mesial and distal furcations of maxillary 1st and 2nd molars accounted for 57%, 18% and 43% of 1st molar furcations, and 83%, 43% and 65% of 2nd molar furcations, respectively. In the buccal and lingual areas of mandibular 1st and 2nd molars, they accounted for 36% and 52%, and 63% and 61% of the furcations, respectively. (4) The majority of mean FEDs in 2nd molars were less than the blade width of new Gracey curettes, whereas in 1st molars they were similar to the blade width of unused Gracey curettes. (5) Most mean FEDs in 1st and 2nd molars were greater than the width of unused Cavitron tips. (6) To achieve complete debridement of root surfaces within furcations, an appropriate selection and combination of Cavitron tips and periodontal curettes should be considered.     

The effectiveness of the Titan-S sonic scaler versus curettes in the removal of subgingival calculus. A human surgical evaluation

This study evaluated clinically the effectiveness of hand versus sonic subgingival scaling and root planing in the removal of calculus by visually examining the root surface at the time of periodontal flap surgery. Consideration was given to the method of instrumentation, probing depth, number of roots, and type of tooth surface. Eleven patients with moderate to advanced periodontal disease were evaluated. Four subjects were scaled and root planed with the Titan-S only, four with curettes only, and three with the Titan-S + curettes. At reevaluation 3 to 6 weeks after scaling and root planing, the decision to perform periodontal flap surgery was made based upon probing depth, bleeding upon probing, previous access to the root surface, furcation involvement, and the patient's level of oral hygiene. A full thickness mucoperiosteal flap was elevated to gain access to the root surface and measure the distance from the cementoenamel junction to the residual calculus. A total of 690 surfaces were evaluated surgically. The percentage of surfaces with residual calculus for each method of instrumentation was: Titan-S only (31.9%), curettes only (26.8%), and Titan-S + curettes (16.9%). Overall, 15.7% of the surfaces probing 0 to 3 mm, 29.3% of the surfaces probing 4 to 5 mm, and 44.4% of the surfaces probing 6 to 12 mm had residual calculus.(ABSTRACT TRUNCATED AT 250 WORDS)     

Periodontal healing after scaling and root planing with the Kavo Sonicflex and Titan-S sonic scalers

Several types of air turbine scalers have recently been introduced as alternatives to hand instruments and ultrasonic devices in periodontal therapy. Whereas differences in scaling and root planing efficiencies have been demonstrated in vitro between different types of sonic scalers (Lie & Leknes 1985), periodontal healing after instrumentation with the Titan-S sonic scaler, Cavitron ultra sonic scalers and hand instruments has shown to be similar (Gellini et al. 1986, Loos et al. 1987, Laurell & Pettersson 1988). This split mouth designed study compared periodontal healing expressed as reduction in number of sites with probing depths of 4 mm or deeper and bleeding on probing following scaling and root planing with the Sonicflex and the Titan-S sonic scalers. Fifteen patients with moderately advanced periodontitis participated in the study. In each patient one side of the dentition was treated with the Sonicflex and the other with the Titan-S sonic scalers. Reexaminations performed three and seven months after treatment showed significant and similar reductions in number of sites with probing depths of greater than or equal to 4 mm and bleeding scores for the two sides.     

下颌第一磨牙根分叉病变治疗随访27年1例

下颌第一磨牙根分叉处解剖结构复杂,牙周破坏累及根分叉后,清洁困难,影响其临床预后.27年前患者因"右下后牙松动"就诊,X线根尖片显示46牙根分叉处牙槽骨破坏;经翻瓣术后,定期牙周维护治疗.3年前复诊,临床诊断为Ⅲ度根分叉病变,经过翻瓣术+隧道成形术治疗后,2、9、24和33个月复查显示牙周组织健康.本病例27年的随访结...     

A scanning electron microscopic investigation of accessory foramina in the furcation and pulp chamber floor of molar teeth

Observations of the pulp chamber floor and furcation surface of human maxillary and mandibular first and second molars were made with the scanning electron microscopic to determine the incidence, size, and location of patent accessory foramina. Accessory foramina on both the pulp chamber floor and the furcation surface were found in 36% of maxillary first molars, 12% of maxillary second molars, 32% of mandibular first molars, and 24% of mandibular second molars. Mandibular teeth had a higher incidence (56%) of foramina involving both the pulp chamber floor and furcation surface than did the maxillary teeth (48%).     

Proof of efficacy of different modified sonic sealer inserts used for debridement in furcations – a dummy head trial

Abstract The purpose of this study was to determine the suitability of different scaling instruments for surgical removal of hard and soft bacterial deposits and for the removal of soft accretions only for maintenance treatment within furcations. 12 upper and 12 lower plastic replicated molars, with through-and-through furcations, were instrumented 3× with 4 different types of instruments: (1) hand instruments: (2) a conventional sonic sealer insert: (3) a set of 3 modified sonic sealer inserts with budded tips and different angulated shafts; (4) a set of 3 sonic sealer inserts with a plastic- coating and different angulated shafts. The plastic replicas were fixed in a dummy head without any replicated soft tissues. In the furcation area, an easily removable surface coating material was applied to the teeth to represent the “plaque” and a second, more stubborn lacquer layer representing “calculus/cementum”. Following instrumentation, the following parameters were recorded to assess efficacy: time required for instrumentation, loss of weight, depth of substance removal at the furcation entrance, % of furcation area instrumented, whereby removal of these 2 layers was judged separately. Only minor differences were observed between hand instruments, conventional and budded sonic sealer inserts as to loss of weight, depth of substance loss and area instrumented. The plastic-coated sonic sealer inserts were just as effective in surface layer removal representing “plaque” as the 3 other instruments, but resulted in less loss of weight and less depth of substance removal. In conclusion, the more aggressive hand instruments, the conventional and budded sonic sealer insert, are preferably used for the surgical phase to increased ease of entry into the furcation dome. An effective debridement of the furcation roof seems only possible with an odontoplastic, for which a furcation is fitted to the instrument by means of an intensive instrumentation, thus leading to weight loss and pronounced substance removal. The plastic-coated sonic sealer inserts seems to be a reasonable choice for maintenance treatment within furcation, since this treatment phase is usually restricted to removal of soft bacterial deposits.     

Calculus removal from multirooted teeth with and without surgical access

Abstract The purpose of this study was to evaluate the efficacy of the calculus removal from multirooted teeth after closed root planing, open root planing and use of a rotary diamond for the furcation area. The effect of pocket depth on the effectiveness of calculus removal was also examined. 30 first and second lower molars scheduled for extraction, with a calculus index 2 and a degree II or III furcation involvement, were divided into 3 groups: 10 molars were scaled and root planed using a closed approach; 10 molars were scaled and root planed using an open approach; 10 molars were scaled and root planed with an open approach and rotary diamond was used for removal of deposits in the furcation area. After extraction, the teeth were assessed in a stereomicroscope and the % of residual calculus was calculated on external and furcation surfaces. The % of residual calculus on the external surfaces was significantly higher after closed than open root planing (p=0.002). Pocket depth affected the effectiveness of scaling and root planing, with more residual calculus observed for depths 7 mm for both groups. Differences between the 3 groups in the % of residual calculus on furcation surfaces were statistically significant (p<0.0001 and p<0.0005). The most effective method was the combination of open root planing and rotary diamond. More calculus was observed in all groups for pocket depths 7 mm but the difference was significant only in the closed group (p=0.006). Closed root planing left more surfaces with residual calculus in the flute (70%) and the roof (60%) of the furcation than open root planing (35% and 50%). However, the most effective method was the use of rotary diamond, particularly for the flute area where residual calculus was detected on only 5% of the surfaces.     

Calculus removal from multirooted teeth with and without surgical access

Abstract The purpose of this study was to evaluate the effect of furcation entrance width on the efficacy of calculus removal from furcation areas as well as to compare this efficacy between external and furcation surfaces after closed root planing, open root planing and use of a rotary diamond for the furcation area. 30 first and second lower molars scheduled for extraction with a calculus index 2 and a degree II or III furcation involvement were divided into 3 groups: 10 molars were scaled and root planed using a closed approach; 10 molars were scaled and root planed using an open approach; 10 molars were scaled and root planed with an open approach and rotary diamond was used for removal of deposits in the furcation area. After extraction, the width of the furcation entrance was measured buccally and lingually 2 mm apical from the bifurcation and furcations were categorized as wide (width >2.4 mm) or narrow (width <2.4 mm). The teeth were assessed in a stereomicroscope and the % of residual calculus on external and furcation surfaces was calculated. The width of the furcation entrance influenced the efficacy in root planing in the open group (p=0.0015). The use of rotary diamond was the most effective method for removing calculus both for narrow and wide furcations. The effectiveness of open root planing in the mesial root was related to the width of the furcation entrance where the % of residual calculus was significantly higher for narrow furcations (p= 0.008). Comparison between external and furcation surfaces showed that the mean values of residual calculus in the closed and open groups were lower for the external than for the furcation surfaces, but the difference was statistically significant only for the closed group (p= 0.013). When open root planing was combined with the use of rotary diamond in the furcation areas, a smaller amount of residual calculus was observed for the furcation than for the external surfaces.     

Morphological measurements of anatomic landmarks in pulp chambers of human maxillary furcated bicuspids

The aim of this in vitro study was to measure key morphological features of pulp chambers from furcated maxillary bicuspid teeth. There were 107 random human maxillary bicuspid teeth used. Each bicuspid was radiographed using the Trophy RVG digital imaging system and a Belmont Acuray X-ray at 70 kVp. Measurements were made using the Digipan measuring mode of the Trophy system. Results were mean (mm): pulp chamber floor to furcation: 1.85 +/- 0.85; pulp chamber ceiling to furcation: 4.61 +/- 1.04; cusp to furcation: 11.55 +/- 1.12; cusp to pulp chamber ceiling: 6.94 +/- 0.70; pulp chamber height: 2.76 +/- 0.97. The measurements showing the lowest percentage variance were: cusp to furcation (9.70%) and cusp to pulp chamber ceiling (10.09%). The only measurement that was statistically the same across maxillary molars, mandibular molars and bicuspids was measurement "B," pulp chamber ceiling to furcation. The critical distance from cusp tip to pulp chamber ceiling in bicuspids was approximately 7.00 mm.     

Periodontal implications of furcation entrance dimensions in Chinese first permanent molars

Narrow dimensions of the entrance to furcations of multi-rooted teeth can complicate the periodontal management of furcation involvements. The objectives of this study were to measure the furcation entrance dimensions of first permanent molars from Hong Kong Chinese, and to compare these dimensions with those of the blade widths of periodontal instruments generally advocated for root surface instrumentation. A total of 363 first permanent molars, of which 185 were maxillary, were examined under 1.5 x magnification. Furcation entrance dimensions were measured using calibrated test gauges ranging from 0.3 mm to 1.5 mm. Furcation entrance dimensions equal to or less than 0.75 mm (the blade width of a new Gracey curet being 0.76 mm) in maxillary first molars were found in 79% of buccal entrances, 39% of mesial entrances, and 43% of distal entrances. In mandibular first molars, entrance dimensions equal to or less than 0.75 mm were encountered in 36% and 47% of buccal and lingual furcation entrances respectively. One-half of all furcation entrance dimensions of these first molars were less than the blade width of new Gracey curets. This high prevalence of narrow furcation entrances should be considered in the periodontal management of furcation involvement of first molars in Chinese.     

Incidence of patent furcal accessory canals in permanent molars of a Turkish population

Aim To determine the incidence of patent furcal accessory canals in permanent molars of a Turkish population. Methodology Two‐hundred extracted teeth consisting of 50 maxillary first molars, 50 maxillary second molars, 50 mandibular first molars and 50 mandibular second molars from Turkish patients attending the Oral Surgery Department of the Faculty of Dentistry, ?stanbul University, ?stanbul, Turkey, were included in the study. After preparation of access cavities and removal of pulp tissue, the teeth were stored in 5.25% sodium hypochlorite for 1 h. Following double‐sealing of the access cavities, all tooth surfaces except the furcation regions were covered with nail varnish. The teeth were stored in 0.5% basic fuchsin for 1 week. The teeth were sectioned at the cemento‐enamel junction and the presence of patent furcal canals was established by examining the pulp chamber floor with a stereomicroscope (10×) to determine staining. Results Patent furcal accessory canals were detected in 24% of maxillary first molars, 16% of maxillary second molars, 24% of mandibular first molars, and 20% of mandibular second molars. No statistically significant differences were found between the tooth types. Conclusions In a Turkish population, the incidence of patent furcal accessory canals on the pulp chamber floor of maxillary and mandibular first and second molars ranged between 16 and 24%.     

Effects of debridement with an ultrasonic furcation tip in degree II furcation involvement of mandibular molars

The purpose of this study was to evaluate the clinical effects of closed debridement with an ultrasonic furcation tip in degree II furcation involvement of mandibular molars. Fifteen patients with degree II furcation involvement in mandibular first and/ or second molars participated in the study. All patients were given oral hygiene instruction. Plaque score, probing depth, probing attachment level and bleeding on probing were recorded at baseline, 1, 4, 8 and 12 weeks. Following a baseline examination, a single episode of supra- and subgingival debridement was provided using an ultrasonic furcation tip in the test group, and an ultrasonic conventional tip and hand scalers under local anesthesia in the control group. At baseline, the mean horizontal probing depth in the test group was 6.35 mm and in the control group 6.06 mm. These values decreased to 4.88 mm and 5.29 mm respectively after 12 weeks. There were horizontal probing attachment gains of 1.29 mm in the test group and 0.59 mm in the control group after 12 weeks (P < 0.01). The bleeding scores were 1.0 in the test group and 0.88 in control group at baseline. These scores were improved to 0.12 in the test group and 0.59 in the control group after 12 weeks (P < 0.01). The results suggest that ultrasonic debridement with a furcation tip has a significantly better potential in treating degree II furcation involvement of mandibular molars.     

Furcation topography of the maxillary and mandibular first molars

The objective of the present study was to describe the topography of the furcation area of the maxillary and mandibular first molars. By using a photogrammetric method, the furcation areas of extracted teeth were plotted to obtain 3-dimensional contour maps. By comparing the individual 10 drawings of the maxillary and mandibular first molars, respectively, some morphological characteristics of the furcation areas could be described. Accordingly, the study showed the complexity of the furcation areas with presence of a number of small ridges, peaks and pits forming a mixture of convexities and concavities.     

Crown lengthening in mandibular molars: a 5-year retrospective radiographic analysis

BACKGROUND: Crown lengthening procedures are a significant part of the periodontist's armamentarium. In order to recreate the clinical space lost to caries or trauma necessary for prosthetic restoration, osseous surgery is often required. If the procedure is not carefully planned, it may result in furcation involvement of multirooted teeth. METHODS: Twenty-six subjects with 26 mandibular molar teeth requiring crown lengthening procedures prior to prosthetic crown placement were evaluated. Nineteen subjects with 24 prosthetic crowns on lower molars which had not undergone crown lengthening were included as control teeth. Bite-wing radiographs prior to surgery (for the test group) or placement of the crown (control group) and 5 years after completion of the prosthesis were compared and analyzed. RESULTS: Of the 26 test teeth, 10 teeth (38.5%) were found to have radiographic evidence of furcation involvement, whereas none of the control teeth developed furcation invasions. CONCLUSION: A critical distance from the furcation (CDF) of 4 mm was established as a landmark under which, if surgery was performed on mandibular molars, chances of furcation involvement in the future were very high.     

The assessment of ultrasonic root surface debridement by determination of residual endotoxin levels

Recent demonstrations of the superficial nature and ease of removal of root-surface-associated cytotoxic materials suggest that extensive root-surface instrumentation is not warranted clinically. This in vitro investigation determined the detoxifying effects of a conservative regime of ultrasonic root debridement, using the Limulus amoebocyte lysate assay for lipopolysaccharide (LPS) as an indication of the presence or absence of cytotoxic materials. 20 extracted periodontally-involved single-rooted teeth, with no clinically detectable calculus deposits, were debrided with a Cavitron TF-10 tip. Light pressure, resulting from a force application of approximately 50 g, lasting for 0.8 s/mm2 of root surface was used and complete overlapping instrumentation ensured. The finding of LPS levels of less than 2.5 ng per root in 19 out of 20 teeth after such debridement was comparable to LPS levels found on healthy, uninvolved control teeth, and thus endorses the growing belief that root surface cleanliness can be readily achieved.