Comparative reproducibility of proximal probing depth using electronic pressure-controlled and hand probing

Abstract This investigation assessed the effect of an electronic pressure-sensitive probe on the reproducibility of probing-depth measurement. Clinical measurements were made at the mesial and distal aspects of all teeth from the buccal and palatal or lingual aspects. Probing was carried out either in a conventional manner using gentle pressure referred to as hand probing or using an electronic pressure-sensitive probe set at 25 g and referred to as pressure-controlled probing. Probing-depth recordings were repeated for one randomly selected quadrant in each subject with random application of the 4 different combinations of pressure-controlled and hand probing. A total of 2584 replicate pairs of probing depth measurements were recorded on 4 proximal surfaces in 646 teeth in 100 adult subjects. The majority (98%) of all repeated measurements were within 1 mm of the initial values. The highest levels of agreement resulted when the same probing method was used at both examinations with electronic pressure-controlled probing being superior to hand probing regardless of tooth position or site. Duplicate measurements recorded with combinations of hand and pressure-controlled probing showed significant systematic bias towards shallower pocket depths with electronic pressure-controlled probing.     

Relationship of gingival thickness and bleeding to loss of probing attachment in shallow sites following nonsurgical periodontal therapy

Periodontal sites of shallow initial probing depth often seem to lose probing attachment following various types of periodontal therapy, including nonsurgical therapy. The susceptibility to this treatment-associated probing attachment loss may conceivably be related to gingival architecture as well as to the inflammatory status of the tissues. This study was designed to study the relationship of buccolingual gingival thickness and bleeding on probing in shallow buccal sites (less than or equal to 3.5 mm probing depth) to loss of probing attachment following nonsurgical therapy. 3 months following treatment consisting of oral hygiene instruction and supra- and subgingival debridement, thin (less than or equal to 1.5 mm), initially non-bleeding sites displayed a mean loss of probing attachment of 0.3 mm. Thick (greater than or equal to 2.0 mm), non-bleeding sites displayed a less noticeable mean loss of probing attachment, whereas bleeding sites of both categories of gingival thickness showed a tendency towards gains in probing attachment levels. It may be concluded that the mean loss in probing attachment levels, commonly seen for shallow sites post-therapy, may be primarily due to the changes in shallow, thin healthy areas.     

Bleeding on probing as it relates to probing pressure and gingival health

The present study was designed to determine the threshold pressure value to be applied in provoking bleeding on probing (BOP) in clinically healthy gingival units. 12 female dental hygiene students volunteered for the study. They were selected on the basis of excellent oral hygiene standards, absence of probing depths greater than 3 mm and absence of caries or dental restorations on smooth and proximal tooth surfaces. Applying a probing force of 0.25, 0.5, 0.75 and 1.0 N in one of the 4 jaw quadrants, respectively, on 2 different occasions with an interval of 10 days, bleeding on probing was assessed. Oral hygiene and gingival conditions were determined using the criteria of the plaque control record and the gingival index. On the basis of the BOP values, obtained using the lowest probing force (0.25 N), the subjects were divided into 2 groups: group 1 ("minimal BOP" value) consisted of 6 subjects yielding practically no bleeding (mean BOP = 0.9%) at both examinations, while the subjects of group 2 ("low BOP" value) had slightly higher BOP% (mean BOP = 13.4%). Both groups showed significant increase in mean BOP% with increasing probing force (0.9%-36.1% in group 1 and 13.4%-47.0% in group 2). Regression analysis revealed an almost linear correlation and a high correlation coefficient between BOP% and probing force. The comparison of the regression lines of the 2 groups showed almost identical slope inclination. However, slight differences in slope inclination were found for different sites: approximal sites clearly yielded steeper regression lines than buccal/oral sites.(ABSTRACT TRUNCATED AT 250 WORDS)     

Variance components of gingival thickness

OBJECTIVES: Distinct periodontal phenotypes have been identified by cluster analysis, which is an explorative method with very low external validity. The aim of the present study was to investigate variance components of facial gingival thickness in young adults with mild gingivitis. MATERIAL AND METHODS: Thirty-three non-smoking females, 18-23 years of age, with mild or moderate plaque-induced gingivitis participated. Gingival thickness was measured at every tooth present by use of ultrasound technology to the next 0.1 mm with a lowest measurement of 0.5 mm. Periodontal probing depth and clinical attachment level were measured with a pressure-controlled probe. Gingival bleeding index was assessed after probing on a 0-2 scale, where 1 was slight, and 2 was profuse bleeding on probing. The Silness-Loe plaque index was recorded. Multilevel variance components and random intercept models were built. RESULTS: A 2-level (subject, tooth) variance component model of gingival thickness without any explanatory variable revealed an intercept (mean) of 0.93 +/- 0.02 mm. Subject variation of gingival thickness amounted to 4.2% of the total variance. Addition of tooth- and subject-related covariates to the model revealed, after adjusting for tooth type, an association with periodontal probing depth (estimated coefficient 0.067 +/- 0.025), and considerable association with average bleeding index (-0.395 +/- 0.149) and plaque index (0.125 +/- 0.048). Variation at the tooth level was drastically reduced; subject variation amounted to 5.2%. CONCLUSION: Gingival thickness is mainly associated with tooth-related variables. Bleeding tendency is higher if gingiva is thin. Subject variability related to periodontal phenotype may add to the total variance, however, to a very low extent.     

Ultrasonic determination of gingival thickness

Abstract The objectives of the present study were (I) to determine the validity and reliability of measuring gingival thickness (GTH) with a recently developed, commercially available ultrasonic device: (II) to measure GTH in relation to tooth type and age of proband;(III) to correlate GTH with varying forms of pre-molars, canines and incisors. Ultrasonic measurements were performed in 200 periodontally healthy, male probands representing 3 different age groups (20–25, 40–45, 55–60 years). In the maxilla, mean GTH varied between 0.9 mm (canines, 1st molars) and 1.3 mm (2nd molars). In the mandible respective mean values ranged between 0.8 mm (canines) and 1.5 mm (2nd molars). No differences in means and standard deviations (0.36–0.39 mm) were observed in different age groups. In order to correlate GTH with other clinical parameters and form of tooth, in 42 probands of the youngest age group, presenting with no attrition or abrasion, no artificial crown restorations and (following prophylaxis) no overt gingivitis and no periodontal probing depth in excess of 3 mm. detailed clinical measurements and stone model cast analyses were performed. By stepwise multiple linear regression analysis, 24% (p < 0.0001) of the variation of GTH was explained by probing depth, recession, width of gingiva and tooth type. The ratio of the width of the crown to its length was not included into the model. When performing analysis of covariance with the subject as factor, the model was improved, now explaining 41% of the variation of GTH. In this model, the influence of periodontal probing depth was decreased, and recession was not included. It was concluded that there are individual differences in GTH (i.e., different biotypes). However, thickness mainly depends on tooth type and is correlated with width of gingiva. There appears to be no association with shape and form of the tooth. Validity and reliability of measuring GTH with the ultrasonic device was found to be excellent.     

Relationship between gingival inflammation and painfulness of periodontal probing

The relationship of gingival inflammation to the pain associated with periodontal probing was assessed at baseline (B), and 1 month (1M) and 3 months (3M) later in 46 subjects. At each of the 3 sessions, clinical measures of gingival inflammation included an observational gingival index and bleeding score. In addition, periodontal probings of all existing teeth was performed with a constant force probe (25 g). Following completion of the probing at each session, subjects rated the global painfulness of the probing using a visual analog scale for pain. Results of this study showed that judged painfulness of probing was related to clinical inflammation (bleeding score) at baseline and 1 month and suggest that the degree of periodontal inflammation is related to the pain and discomfort associated with periodontal probing.     

Relationships between alveolar bone levels measured at surgery, estimated by transgingival probing and clinical attachment level measurements

Alveolar bone level measurements obtained by transgingival probing were compared with alveolar bone levels measured during surgery at 178 sites in 9 patients. Probing depth measurements using constant loads of 30 g and 60 g were also compared with bone levels measured at surgery at the above sites. The effects of inflammation, location of the site on the tooth surface and tooth type were also investigated. Transgingival probing was unaffected by these factors and proved to be an accurate method of measuring alveolar bone levels (r = 0.975). Probing depth measurements were affected by the presence of inflammation, assessed by the bleeding response to probing, and variation in probing load. The effect of inflammation was to reduce the mean distance between the probe tip and the alveolar bone from 2.4 mm to 1.9 mm. None of the relationships between the measurements were significantly affected by the location of the site on the tooth surface, or by tooth type.     

Assessment of gingival thickness in the maxillary anterior region using different techniques

Clinical Oral Investigations - Gingival phenotype is closely related to treatment success and aesthetic results in the maxillary anterior region. Several methods were proposed to measure the...     

B-mode versus A-mode ultrasonographic measurements of mucosal thickness in vivo.

OBJECTIVE: The objective of this study was to compare the measurement accuracy of A-mode and B-mode ultrasonographic assessments of palatal masticatory mucosal thickness in vivo. STUDY DESIGN: Thickness of palatal masticatory mucosa in the molar region of 50 volunteers was measured once with a B-mode ultrasound device (10 MHz) combined with a standoff for intraoral applications. At identical reading points thickness was also assessed with an A-mode device (5 replicates) and by needle probing for determination of true thickness. RESULTS: On average true thickness ranged between 2.9 and 3.3 mm (95% confidence intervals; median, 3.1 mm). B-mode ultrasonography overestimated truth by 0.19 mm (median) and differed significantly from truth (P =.008), whereas A-mode ultrasonography slightly underestimated true thickness by -0.05 mm (median). Limits of agreement were wider for A-mode ultrasonography (2.00 mm) than for B-mode ultrasonography (0.88 mm). CONCLUSIONS: Because accuracy of 0.2 mm is acceptable for many clinical indications, B-mode and A-mode yield sufficient accuracy for measurements of mucosal thickness.     

The transgingival approach for placement of distraction implants.

PURPOSE: Since 1997, distraction implants have been clinically used for alveolar ridge distraction and, later, for prosthetic treatment. While 63 patients have been treated by the authors by alveolar ridge distraction with distraction implants with an open approach, the aim of this study was to demonstrate a minimally invasive technique of distractor placement via a transgingival approach. PATIENTS AND METHODS: Twelve patients were treated with a modified surgical incision using distraction implants. A tissue punch was used to remove transgingival mucosa, and a segmental osteotomy was performed using a vestibular incision. The distracted segment was pedicled at the lingual and crestal mucoperiosteum. Distraction was carried out for 0.5 mm per day, divided into 2 to 4 turns per day. A distraction of 5 to 7 mm was performed. At the end of distraction, the distraction insert was changed into a definitive stable implant insert. Prosthetic treatment was performed 4 months after the distraction period with fixed superstructures. The follow-up was performed with the aid of dental radiographs, evaluation of peri-implant probing depths, and Periotest values (Siemans, Bensheim, Germany). RESULTS: The outcome of this technique showed minimal scarring of the gingiva with good aesthetic results, the clinical and radiologic findings were satisfying, and the Periotest values were negative at every examination. The rate of complications was low. CONCLUSION: Minimal scarring and good aesthetic and functional outcome resulted in patients with alveolar ridge distraction performed with a transgingival approach.     

Effect of gingival wall on resistance to probing forces

Abstract This study was conducted to determine whether the gingival tissue lateral 10 the periodontal sulcus contributes resistance to the advancement of a periodontal probe tip into the sulcus under different applied pressures. An electromechanical device was used to advance a probe tip 0.6 mm in diameter into the facial sulcus at a constant speed until resisting forces of 0.70 N were encountered. The device registered the resisting force and probe advancement simultaneously. The gingiva of all 2nd incisors, 2nd premolars, and 1st molars of 4 young adult male beagle dogs were tested. After the first measurement, the buccal gingiva of experimental sites were incised mesiodistally from the gingival margin to the alveolar crest and the sulcus was reprobed. 2 experimental and control quadrants were selected randomly resulting in 6 sets of both experimental and control data from each animal. The data were analyzed with analysis of variance. The analysis demonstrated significant variation from site to site, and dog to dog; therefore, only changes between the 1st and 2nd probings at the same sites could be compared. Less variability of probing distance in different animals occurred at higher forces; however, the incision had a significant effect on probing distance at these forces. The pressure at which probing distance had less variability among animals and least affected when the gingival sulcular wall was incised was estimated to be 106 N/cm². This corresponds to 30 g force on the 0.6 mm diameter probe.     

Repeatability of ultrasonic determination of gingival thickness

The aim of the present study was to assess the degree of disagreement of ultrasonic measurements of gingival thickness at different teeth. Gingival thickness was determined in 33 volunteers with plaque-induced gingivitis. Facial/buccal gingiva was measured at the level of the gingival sulcus depth. Measurements were repeated after 2 and 4 weeks. A repeated measures, two-level (occasion, subject), variance components model revealed a within-subject variance of 0.187 mm² resulting in a repeatability coefficient of 1.20 mm. When modeling level 1 (occasion) variance as a function of tooth type, respective error terms were used for calculating 95% repeatability coefficients for different teeth. Unreliable measurements were largely confined to upper and lower second and third molars. Error terms were lowest (0.03–0.05) at upper canines and first premolars as well as lower anterior teeth and premolars, where repeatability coefficients of 0.5 to 0.6 mm could be estimated. It was concluded that performance of the device was best at certain tooth types with rather thin gingiva. The present resolution and rather high degree of disagreement may preclude, however, detection of minute increases in thickness in the micrometer range, which seem to occur during gingivitis.     

In vivo measurements of gingival thickness]

The substantiation of periodontal changes and the evacuation of their course must always involve exact measurements. Up to now the thickness of the gingiva and its dimensional changes have been neglected in most studies though such data may be very revealing in assessing the tissue. The author designed a device which permits to measure the recession of the gingiva with an accuracy of 1/10 mm and to determine exactly the thickness of the gingiva. The thickness of the gingiva was measured in a group of patients undergoing an oral irrigation cure. An initial soft-tissue reaction (in which the opening of terminal vessels and swelling processes seems to prevail over the flooding-out of oedemas) is followed by a small reduction in gingival thickness (presumably associated with the flooding-out of oedemas). The results so far obtained correspond to the clinical, stomatoscopical and bioptical observations.     

Relationship between periodontal probing velocity and gingival inflammation in human subjects

Abstract Little is known about the biophysical characteristics of the dentogingival junction in response to the development or resolution of inflammation. The Toronto Automated Periodontal Probe (TAPP) provides an estimate of the integrity of the dentogingival junction by measuring intrapocket probing velocity. The aim of this study was to measure changes of probing velocity in inflamed human periodontium before and after subgingival debridement. 32 subjects exhibiting gingival inflammation were selected; 29 completed the study. Gingival index (GI), plaque index (PLI), bleeding index (BI) and the rate of gingival crevicular fluid flow (CFF) were measured as concomitant variables. The experimental group (N= 16) received scaling, root planing and oral hygiene instruction at baseline. The control group (N=13) received no treatment until after 28 days. Subjects were seen at baseline, day 14, 21 and 28 for measurement of probing velocity and concomitant variables on 6 index teeth. At day 28, the control group was treated and then reassessed 28 days later. The experimental group showed a reduction of 51.6% for mean crevicular fluid flow (p<0.0001), 79.7% for mean plaque index (p<0.0001), 58.0% for mean gingival index (p<0.0001), and 72.0% for mean bleeding index (p<0.002) at day 28, confirming that inflammation was reduced compared with baseline. No significant changes were observed in the control group until after treatment. The velocity of probing and the formation of a plateau in the velocity profile were recorded. The experimental group demonstrated a significant increase (p<0.002) in the frequency of plateau formation and a decrease in mean slope between baseline and day 28 (p<0.02). No significant change was observed in the control until day 56, 28 days after treatment. These data indicate a direct relationship between improved clinical health and increased resistance to probe penetration near the base of the pocket, as reflected by the increased frequency of plateau formation and decreased slope for the terminal segment of the velocity profile curve.     

Comparative data on facial morphology and muscle thickness using ultrasonography

The purpose of this investigation was to measure the thickness of the masseter, levator labii superioris, and zygomaticus major muscles; to examine the reproducibility of ultrasonographically measured muscle thickness; to evaluate the association between facial and masticatory muscle thickness and vertical facial pattern; and to test whether the variation in muscle thickness is related to the variation in the body mass index (BMI) of different individuals. The thickness of the masseter, levator labii superioris and zygomaticus major muscles was measured bilaterally by ultrasonography in 47 (23 females, 24 males) healthy, fully-dentate young adults who volunteered for the study. The measurements for each individual were performed twice for the masseter muscle: during relaxation and during maximal clenching. Standardized lateral cephalograms of the subjects were traced to determine their facial morphology. The data obtained from the lateral cephalograms were used to divide the subjects into three groups according to their vertical facial pattern: low angle (n = 14), high angle (n = 17) and normal (n = 16). In the low angle group, the mean masseter muscle thickness was 15.20 (+/- 1.90) mm under relaxed conditions and 16.31 (+/- 2.18) mm during maximal clenching. In the high angle group, the respective measurements were 13.29 (+/- 2.52) mm and 14.72 (+/- 2.63) mm. In the vertically normal group, they were 13.56 (+/- 1.95) mm and 14.57 (+/- 1.83) mm. There was no relationship between vertical growth of the face and the thickness of the investigated muscles of facial expression. Masseter muscle thickness was found to be significantly correlated to vertical facial pattern and BMI, showing that individuals with a thick masseter had a vertically shorter facial pattern, whereas the muscles of facial expression showed no relationship with vertical facial pattern.