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Objective: To explore the mechanism of catechol-O-methyltransferase (COMT) in tooth movement pain., Methods: The experimental groups were randomly allocated into the healthy control, sham operation, model, model+shCOMT experimental, model+shCOMT control, and model+COMT antagonist groups. A tooth movement pain model was established. The pain stimulation and behavior test were performed. The duration of grooming behavior was determined. The appropriate experimental force and duration for application were selected. COMT shRNA vector was constructed and packaged as adenovirus. The shCOMT adenovirus was injected into the left infraorbital foramen. Seven days later, the trigeminal ganglia of all treatment groups were obtained. The COMT and IL-17 expressions were detected by western blot. The appropriate COMT antagonist concentration was selected. The pathological results of each group were detected by HE staining. The tooth movement distance was determined. The COMT gene expression was detected by FISH. The COMT and IL-17 expressions in the right trigeminal ganglion tissue of each group were detected by western blot., Results: The 60 g force and 14-day duration required the lowest stimulus intensity, the duration of grooming behavior was the longest, and the effect on COMT and IL-17 was the most significant. In the model group, formation of digestive cavity was seen in the trigeminal ganglion tissue, with infiltration of inflammatory cells, upregulation of the COMT and IL-17 expressions, and significant increase in the tooth movement distance. Compared with the model group, the shCOMT experimental group and the COMT antagonist group significantly improved the trigeminal ganglion tissue injury, significantly decreased the tooth movement distance, and significantly inhibited the COMT and IL-17 expressions., Conclusion: The efficiency of tooth movement can be influenced by interfering the COMT-related gene expression. This proves that the COMT system can regulate the orthodontic tooth movement pain., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2021 Yonglong Zhou et al.)

Introduction: To assess effect of orthodontic treatment on anterior or lateral functional shift in mixed dentition stage by telemonitoring mandibular movements in four-dimensions using a novel objective method that can assist in orthodontics and other dental specialties without the need of expensive, bulky or complicated equipment., Methods: A sample of 60 patients was divided into two groups. Group I included 30 patients with normal occlusion and TMJ functions. Group II included 30 patients that were diagnosed with an abnormal path of closure in antero-posterior or transverse directions due to disharmony between centric occlusion and centric relation. The latter group was orthodontically treated and mandibular movements were measured before, during, directly after orthodontic treatment, and one year after treatment using our proposed method. To evaluate validity and reliability of our method, it was compared with two methods, a commercially available mandibular scanner, and a low-cost graphical method that utilizes a sheet of wax and a stylus., Results: It was found that the overall differences between opening and closing curves of our proposed method and the other two methods were small and negligible (p > 0.05)., Discussion: It was found that our proposed method is offering a reasonably accurate, simple and rapid way to telemonitor the mandible movements in four-dimensions using the rear/front camera of any smart-phone.

The novel aspect of this study was to contextualize the co-localization of biomolecular expression in widened and narrowed periodontal ligament (PDL)-space within a mechanically activated periodontal complex. The PDL is unique as it is the only ligament with both innervation and vascularization. Maxillary molars in 6-week-old male C57BL/6 mice (N = 5) were experimentally translated for 2 weeks using an elastic spacer. Contralateral teeth were used as controls. Mechanical testing of the periodontal complex of a mouse in situ and imaging using X-ray micro-computed tomography (micro-XCT) illustrated deformations within blood vessels (BV) of the PDL. PDL-bone and PDL-cementum entheses at the widened and narrowed PDL-spaces following experimental tooth movement (ETM) illustrated osterix (OSX), bone sialoprotein (BSP), cluster of differentiation 146 (CD146), and protein gene product 9.5 (PGP9.5), indicating active remodeling at these sites. PGP9.5 positive nerve bundles (NBs) were co-localized with multinucleated cells (MCs), Howship's resorption lacunae, and CD146 positive BVs. Association between nerves and MC was complemented by visualizing the proximity of osmium tetroxide stained NBs with the ultrastructure of MCs by performing scanning transmission electron microscopy. Spatial association of NB with BV, and NB with MC, provided insights into the plausible co-activation of NBs to initiate osteoclastic activity. Resorption of mineral occurred as an attempt to restore PDL-space of the load-bearing complex, specifically at the PDL-entheses. Mapping of anatomy-specific structural elements and their association with regenerative molecules by correlating light and electron micrographs provided insights into the use of these extracellular matrix molecules as plausible targets for pharmacological interventions related to tooth movement. Within the realm of tissue regeneration, modulation of load can reverse naturally occurring mineral formation to experimentally induced resorption, and naturally occurring mineral resorption to experimentally induced formation at the enthesial sites to permit tooth translation., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objectives: To investigate the effect of local injection of receptor activator of nuclear factor kappa B ligand (RANKL) on experimental tooth movement and subsequent alveolar bone remodelling in mice., Materials and Methods: Sixty mice were randomised to receive daily local RANKL or phosphate-buffered saline injections in the buccal premaxillary bone for 14 of 21 days of incisor movement, followed by a 21-day retention period. Five mice from each group were euthanised on days 0, 3, 7, 14, 21 and 42, and specimens were prepared for haematoxylin and eosin, tartrate-resistant acid phosphatase and immunohistochemical staining. Five mice from each group were subjected to serial microcomputed tomography until day 42 for tooth movement and bone volume quantification., Results: The experimental group showed significantly greater tooth movement and bone volume reduction on days 14 and 21; an increased osteoclast number on days 3, 7, 14 and 21; and no difference on day 42. Higher RANKL expression was observed on days 7 and 14, with remarkable alkaline phosphatase activity. No significant systemic changes were observed., Conclusion: Local RANKL injection leads to increased osteoclastic activity and facilitates tooth movement, followed by subsequent alveolar bone formation; this implies a reversible transitional acceleration of bone resorption., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd. All rights reserved.)

BACKGROUND The aim of this study was to dynamically evaluate tooth movement, root resorption, and remodeling of alveolar bone using different forces to cause tooth movement in rats. MATERIAL AND METHODS 12-week-old male Sprague-Dawley rats were selected. Nickel-titanium (Ni-Ti) coil springs (20 g, 50 g, and 100 g forces) were placed for mesial movement of the left first maxillary molar teeth. Tooth movement, root resorption, and microarchitectural parameters of the trabecular bone were evaluated by in vivo micro-CT. Histological examination was used to observe the root resorption, alveolar bone remodeling, and changes in osteoclasts from day 0 to day 14. RESULTS The tooth movement distance increased significantly over the initial 3 days in the 3 groups. The 20 g force group showed more tooth movement than in the 50 and 100 g force groups after 14 days (P<0.05). From days 7 to 10, root resorption lacunae appeared in the 3 groups and then stabilized, and the 100 g force group produced more lacunar resorption than in the anther 2 groups (P<0.05). Compared to day 0, the trabecular thickness and bone volume fraction on the pressure side gradually decreased from day 7 to day 14. The structure model index increased significantly from day 3 to day 14. Histological examination showed remarkable root resorption craters and osteoclasts positive for tartrate-resistant acid phosphatase in the root resorption lacunae in the 50 g and 100 g groups from day 7 to day 14. CONCLUSIONS A 100 g heavy force can be used to establish a root resorption model in rats.

During orthodontic treatment, binding teeth, may change the topographically organized representation of teeth in the cerebral cortex. To test the hypothesis that experimental tooth movement (ETM) changes the somatotopy of an individual tooth arrangement in the somatosensory cortex, we examined the spatiotemporal features of cortical excitatory propagation in response to mechanical stimulation of the maxillary incisor or molar using optical imaging in late adolescent rats without or with ETM. The ETM models consisted of 1d, 3d, and 7d ETM in which a closed-coil spring was ligated between the maxillary first molar and incisors. In controls, incisor and molar mechanical stimulation evoked excitation in the rostral and dorsocaudal regions of the primary somatosensory cortex (S1), respectively. In addition, the secondary somatosensory cortex and insular oral region (S2/IOR) were also activated. Incisor stimulation-induced excitatory regions in S1 of 3d and 7d ETM shifted without changing the maximum excitatory area or peak amplitude; the incisor stimulation-responding region moved toward the dorsocaudal region, which responded to molar stimulation in the control. This shift in excitatory region was not observed in 1d ETM. One day after removal of the coil spring that was attached for 6 days, the excitatory region shift in S1 was recovered to the control region. On the other hand, 1d ETM exhibited facilitation of the excitatory area and peak amplitude upon molar stimulation, and the facilitation of excitatory propagation disappeared in 3d and 7d ETM. These results may explain the clinical finding that abnormal sensation temporally occurs during orthodontic treatment., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Objectives: While permanent retention is today the method of choice to stabilize orthodontic treatment outcomes, recent studies have increasingly reported posttreatment changes in tooth position during permanent retention. We conducted this study to analyze changes in the anterior mandible, whether the changes follow an underlying movement pattern, and, aiming for a preventive strategy, whether any risk factors could be identified comparing findings with the pretreatment situations., Methods: We included 30 patients who had worn fixed Twistflex retainers (UK 3-3) extending from canine to canine in the mandible. Casts reflecting the intraoral situations before orthodontic treatment (T0), directly after completion of active therapy (T1), and 6 months later (T2) were scanned and superimposed using Imageware Surfacer software. Posttreatment changes (T2-T1) of tooth position within the retainer block were analyzed on 3D virtual models and were compared to pretreatment (T0) and treatment-related (T1-T0) findings to identify potential risk factors., Results: Almost all analyzed patients revealed three-dimensional changes in tooth position within the retainer block. Comparing these movements, we repeatedly found rotated retainer blocks in labio-oral direction, while the center of rotation was located at the first incisors. This pattern was associated with intercanine expansion and excessive overjet correction during orthodontic treatment. The canines underwent the most pronounced (rotational and translational) movements., Conclusions: In general permanent lingual retainers are safe but in special clinical cases retainers can induce undesired tooth movement. Risk factors seem to be intercanine expansion and excessive overjet correction during orthodontic treatment. In specific cases an additional retention device might be needed.

The impression technique described combines elastomeric impression materials and irreversible hydrocolloid to make an accurate preliminary impression of extremely mobile and misaligned teeth. Upon setting, the materials are removed from the mouth in 3 different directions and reassembled extraorally. This technique provides an alternative, easy, accurate, and safe way to make a preliminary impression of mobile, periodontally involved teeth., (Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.)

Patients who seek dental treatment may have bipolar disorder, and lithium carbonate (LC) is the drug of choice used in the treatment of this disorder. Taking into consideration the controversial results found in the literature, and the possible influence of LC on induced tooth movement, the objective was to evaluate tooth movement induced in rats after administration of lithium carbonate. One hundred and ninety-two rats were divided into 3 groups. In the L group, the animals received daily 60mg/kg of LC, they were not subjected to orthodontic movement, and they were euthanized after 33, 37, 44 or 51 days. In the LM group, the LC was administered for 30 days and during the subsequent 3, 7, 14 and 21 days, corresponding to the period of induced tooth movement, and they received a spring that produced a 30cN force. In the SM group, saline solution was applied. Measurements were made of tooth displacement, the numbers of osteoclasts and serum lithium phosphate (PO4), alkaline phosphatase (ALP) and creatinine levels. The tooth displacement was lower in the LM group compared to the SM group at 44 days. A tendency toward reduction in the number of osteoclasts was observed in the LM group compared to the SM group at 44 days. The average lithium were higher in the L and LM groups compared to the SM group. The opposite was observed for the PO4 group. A higher value for the ALP was found in the L group. The average creatinine level was lower in the LM group. LC inhibited tooth movement for 14 days, possibly due to the reduction in the number of osteoclasts.

The aim of the study was to assess alveolar bone resorption in patients with periodontal disease and individuals with normal periodontal status and coordinate resorbtion rates with tooth mobility. Tooth mobility was measured in 19 patients with periodontal disease and 17 healthy individuals by two-parametrical periodontometry in two different positions: in equilibrium and after pre-loading. The level of bone resorption was determined by periodontal probe. Previously unknown correlation between tooth mobility and alveolar bone resorption was found out meaning that bone atrophy can be determined by tooth mobility.

The aim of the study was the evaluation of the effectiveness of using partial dentures made of thermoplastic materials for patients with generalized periodontitis of I-II degree of severity based on the results of clinical research. The effect of partial dentures made of acrylic, metal and thermoplastic materials with and without splinting elements of fixation on the state of periodontal tissues in patients with generalized periodontitis was studied. The results of clinical studies of patients periodontal tissues condition ,who have had dental defects on the background I-II severity of GP using partial splinting elements of fixation showed a significant improvement in oral hygiene, positive change in activity indicators current of generalized periodontitis. The group of patients for whom were made orthopedic constructions of thermoplastic masses, noticed reducing of the depth of periodontal pockets, tooth mobility, bleeding and inflammation of the interdental papillae and the gingival margin.

Orthodontics contributes to improving self-esteem and function. However, a common refrain in ortho-perio relationships states that orthodontics has no deleterious effects on the healthy or reduced and treated periodontium. Though supported for decades, this idea has now been heavily challenged by a recent systematic review of the literature. The conclusion of this article is unfortunately very clear. There is a lack of reliable evidence showing the beneficial effects of orthodontic treatment on periodontal health with, at best, mild adverse effects. How can we reduce the periodontal cost of orthodontic treatment to a minimum? How can we ensure that this "at best" does not turn into "at worst"? To minimize the adverse effects of orthodontic treatment on periodontal tissues, the orthodontist must be able to determine to which patients he/she can consider providing orthodontic treatment and those for whom prior periodontal treatment is mandatory. In addition to the items collected for an orthodontic diagnosis, the orthodontist must be able to recognize the eight signs of attachment loss., (Copyright © 2013. Published by Elsevier Masson SAS.)

Background: Mast cells are tissue-resident immune cells that participate in a variety of allergic and inflammatory conditions. Limited attention has been given to the role of mast cells in periodontal diseases, and the effects of mast cell degranulation on the chronic stages of non-allergic inflammation, particularly in periodontitis, are not known. The present study analyzes the relationship between the mast cell degranulation and human periodontal disease progression., Methods: A total of 50 clinical specimens including moderate periodontitis (n = 17), advanced periodontitis (n = 18), and healthy control tissues (n = 15) were used in this study. All specimens were fixed in 10% buffered formalin and stained with hematoxylin and eosin for histopathology, with toluidine blue for identifying mast cells, and by immunohistochemistry for the expressions of mast cell tryptase in periodontal tissues. The total and degranulated mast cell densities (per high-power field) were quantified in the specimens., Results: Compared with healthy controls, there were significantly increased both total and degranulated mast cell densities in human moderate (P <0.01) and advanced (P <0.01) periodontitis groups by toluidine blue staining, and there were significantly higher densities of both total and degranulated tryptase-positive mast cell subpopulation in the moderate periodontitis group (P <0.01) and even significantly higher subpopulation densities in the advanced periodontitis group by immunohistochemical staining, in which both total and degranulated mast cell densities were significantly higher in the advanced periodontitis group than those in the moderate periodontitis group (P <0.01) by both toluidine blue staining and immunohistochemical staining. There was significantly more severe periodontal inflammatory pathology in the advanced periodontitis group than in the moderate periodontitis group (P <0.01)., Conclusion: These findings indicate a significant correlation among tryptase-positive mast cell density, the degree of their degranulation, and the human periodontitis severity, and the results of this study further indicate that mast cell degranulation appears to be associated with human periodontal disease.

Background: Periodontal disease is closely related to type 2 diabetes and is an important complication of diabetes. There are few studies about the relationship the glycohemoglobin levels with severity of periodontitis in non-diabetic population. We therefore planned this study to evaluate the glycohemoglobin levels with severity of periodontitis in non-diabetic population., Methods: This study was conducted on 50 age and gender matched subjects in each of the three groups (according to the grades of mobility in periodontitis), a total of 150 non-diabetic periodontitis patients (Grade 1, Grade 2, and Grade 3 mobility) and 50 non-diabetic periodontitis patients with Grade 0 mobility (controls), in collaboration with the Department of Periodontics of Dental College and Department of Biochemistry, PGIMS, Rohtak, Haryana. After obtaining informed consent, fasting venous blood samples of all the non-diabetic periodontitis patients of all grades were collected aseptically for HbA1c, plasma glucose, and serum C-reactive protein (CRP) estimation., Results: A total of 150 non-diabetic periodontitis patients (Grade 1, Grade 2, and Grade 3 mobility) and 50 age and gender matched controls participated in the study. There was no significant difference in fasting plasma glucose and postprandial plasma glucose in non-diabetic periodontitis patients with Grade 1, Grade 2, and Grade 3 mobility as compared to controls, non-diabetic periodontitis patients with Grade 1 mobility as compared to Grade 2, non-diabetic periodontitis patients with Grade 1 mobility as compared to Grade 3 and non-diabetic periodontitis patients with Grade 2 mobility as compared to Grade 3. Glycohemoglobin and serum C-reactive protein levels were significantly increased in non-diabetic periodontitis patients with Grade 1, Grade 2, and Grade 3 mobility as compared to controls, non-diabetic periodontitis patients with Grade 1 mobility as compared to Grade 3 and non-diabetic periodontitis patients with Grade 2 mobility as compared to Grade 3. The difference of serum C-reactive protein levels were significant. However, glycohemoglobin levels were non-significant between non-diabetic periodontitis patients with Grade 1 and Grade 2 mobility., Conclusions: The evidence of association between periodontitis and increased glycohemoglobin increases attention to the diagnosis and treatment of periodontitis, consequently improving the patient's oral health and prevention of occurrence in future diabetes. An understanding of these correlations is important to allow dental health care providers to inform patients with periodontitis of their increased risks and to counsel such patients to seek additional medical assessment or intervention as indicated.

Purpose: Controversy exists as to the most appropriate treatment strategy for myofibromas of the jaws: en bloc resection versus enucleation. The purpose of the present study was to evaluate the treatment outcomes in children with these uncommon benign tumors., Materials and Methods: We performed a retrospective chart review of pediatric patients with jaw myofibromas. The predictor variables included patient demographics, clinical presentation, imaging characteristics, pathologic features, treatment, and follow-up. The outcome variable was cure or recurrence. The descriptive statistics were computed., Results: A total of 12 patients (mean age 6.7 years) met the inclusion criteria. There were 2 presentations: exophytic soft tissue mass in dentoalveolar segment (n = 5); and intraosseous mass (n = 7). No distinct histopathologic differences were found between the 2 groups. Exophytic myofibromas displayed rapid growth, tooth displacement and/or mobility, bony expansion, and/or cortical thinning/perforation. Most were treated by resection. The intraosseous lesions were asymptomatic and/or incidentally discovered. They were treated by enucleation and curettage. The mean follow-up for the 2 groups was 6.5 and 3.9 years, respectively. There were no recurrences., Conclusions: The results of the present study indicate that there are 2 clinical presentations of myofibromas of the jaws in children: an aggressive exophytic type and a nonaggressive intraosseous type. They are histopathologically indistinguishable., (Copyright © 2012 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.)

In vivo measurement of the mobility of teeth under physiological loading has been subject of research for years. Comparing the deflection under load of dental implants with teeth provides valuable input for designing restorations spanning both teeth and implants. Physiological force rise time of about 50-100 ms and displacement of 10-100 μm requires high spatial and temporal resolution of the measurement set-up. Using an optical system attached to the teeth/implants to be measured and a light source attached to a point of reference, displacement of teeth and implants under axial and lateral loading was measured on a series of volunteers. Axial displacement of teeth shows strong time dependence consistent with (hydraulic) damping not observed for lateral loads. Displacement under lateral loading was found to be about one order of magnitude higher than under axial load. For dental implants elastic deflection was observed in axial and lateral direction without measurable influence of the load rise time. For purely axial loading, dental implants and teeth show similar deflection under physiological force rise time but for lateral loading the considerably difference between teeth and implant may put some restrictions on the construction of tooth-implant-bridges, especially for teeth in the anterior region., (Copyright © 2011 Elsevier GmbH. All rights reserved.)

The authors report a case of natal primary molar in a healthy 14-day-old child. The diagnosis of the case and the treatment plan are discussed, as well as histological analyses of the natal tooth. The tooth presented an immature appearance, with high mobility and insertion only in soft tissue, and therefore the clinical option adopted was dental extraction. Histological analyses revealed enamel hypoplasia and dentin showing a typical tubular pattern without alterations. The soft tissue had young and richly vascularized pulp with areas of chronic inflammatory infiltration.

This case report describes surgical exraction of multiple premolar and molar teeth in a Western Lowland gorilla. Postoperative photographs and radiographs indicated complete healing of the extraction sites. This case report includes a review of gorilla dental anatomy, oral disease in primates, pathogenesis of periodontal disease, predisposing factors to periodontal disease, and principles of surgical tooth extraction.

Introduction: Human dental pulp stem/stromal cells (hDPSCs) in adults are primarily derived from the pulp tissues of permanent third molar teeth in existing literatures, whereas no reports exist, to our knowledge, on deriving hDPSCs from a tooth without the need for surgical procedure. The aim of this study was to raise a novel idea to source hDPSCs from complicated crown-fractured teeth requiring root canal therapy., Methods: hDPSCs were harvested from the pulp tissues for two complicated crown-fractured teeth requiring root canal therapy, retaining the teeth for subsequent prosthodontic rehabilitation, in a 41-year-old woman who had suffered a motorcycle accident. Pulp tissue from the left lower deciduous canine of a healthy 10-year-old boy (the positive control) was also removed because of high mobility and cultured for hDPSCs., Results: The hDPSCs derived from the two complicated crown-fractured teeth and the deciduous tooth were able to differentiate into adipogenic, chondrogenic, and osteogenic lineages and also expressed stem cells markers and differentiation markers, which indicated their stem cell origin and differentiation capability. In addition, hDPSCs from both the complicated crown-fractured teeth and the deciduous tooth showed high expression for bone marrow stem cell markers including CD29, CD90, and CD105 and exhibited very low expression of markers specific for hematopoietic cells such as CD14, CD34, and CD45., Conclusions: This report describes the successful isolation and characterization of hDPSCs from the pulp tissue of complicated crown-fractured teeth without tooth extraction. Therefore, pulp exposed in complicated crown-fractured teeth might represent a valuable source of personal hDPSCs.

Background: Hajdu-Cheney syndrome (HCS) is an inheritable, rare disorder of bone metabolism, associated with acro-osteolysis of the distal phalanges, short stature, distinctive craniofacial and skull changes, premature tooth loss, and periodontitis. This report focuses on the periodontal manifestations of HCS., Methods: A 22-year-old female presented with the characteristic clinical features of HCS, including short stature, small face, prominent epicanthal folds, thin lips, small mouth, and short hands. There were no abnormal biochemical, hematological, or hormonal data. Tests for bone mineral density were indicative of osteoporosis. Cephalometric analysis revealed hypoplasia of the midface and increased cranial base angle; the maxilla and the mandible were set posteriorly. The sella turcica was enlarged, elongated, and wide open with slender clinoids. Hair samples were examined by scanning electron microscopy, and tooth cementum and dentin were evaluated histologically., Results: According to the periodontal evaluation, gingival inflammation was 12.5%, bleeding on probing score was 24%, probing depths averaged 4 to 6 mm, and clinical attachment loss averaged 3 to 6 mm. Class II furcations were found on three teeth. Almost all teeth exhibited pathological mobility of varying degrees. There was a generalized, horizontal bone loss of approximately 50%. Three teeth had to be extracted because of severe localized periodontal destruction. Histologic examination of the dentin and the cementum was normal., Conclusions: HCS periodontitis is associated with an unpredictable and uneven, rapid rate of periodontal destruction of unknown etiology. Further research is required to identify the role of the possible pathogenic factors involved.

Purpose: The purpose of this study was to clarify the influence of changes of occlusal contacts on adjacent tooth displacement during articulation., Materials and Methods: The amount and direction of displacement of the maxillary left first molar and adjacent teeth were measured using a displacement transducer, Type M-3. Seven subjects were included in this study. On the maxillary left first molar, 8 experimental occlusal contact points were established using platinum foil and these were divided into 2 groups, the buccal and lingual groups, which corresponded to the buccal and lingual cusps, respectively., Results: During clenching, the buccal group showed differences in the direction of the tooth displacement paths among the 3 teeth (second premolar, first and second molar), but there was no difference in the lingual group and the direction of displacement of these 3 teeth was similar to the natural teeth., Conclusion: It is necessary to make at least one lingual occlusal contact point to obtain displacement of not only the abutment tooth but also the adjacent teeth.

Papillon-Lefevre Syndrome (PLS) is an inherited autosomal recessive disorder presenting with Palmar plantar Keratoderma and Juvenile Periodontitis leading to early loss of both the dentitions. Two cases of PLS in a family with a history of consanguineous descent are presented.

In a comparative evaluation of the effectiveness of two treatment modalities for juvenile periodontitis, 12 patients aged between 15 years and 23 years were recruited into a six months longitudinal study. The split mouth design was used such that one side (upper and lower quadrants) received conservative treatment. Each side was randomly assigned one of the two treatment modalities. Standardized probing attachment level (PAL) measurement and degree of mobility of the teeth were taken at recruitment (baseline), one, three and six months postoperation. Tetracycline capsules 250mg, 6 hourly, was administered for 2 weeks at baseline and at 3 months follow-up. Initial thorough scaling and polishing of the whole mouth was done for all the patients. At follow-up, there were marked improvements seen with both treatment modalities. The mean probing depth for surgical treatment (3.57mm +/- 0.78) was significantly lower than that of conservative treatment (4.11mm +/- 0.74) P < 0.05 at 3 months. Also, this significant difference continued up to 6 months (2.70mm +/- 0.57, 3.55mm +/- 0.65; P < 0.05 ). For the degree of mobility, significant difference was only evident at 6 months of follow-up (0.48 +/- 0.29, 0.98 +/- 0.523; P < 0.05 ) for surgical treatment and conservative treatment respectively. It was therefore concluded that surgical debridement with systemic administration of tetracycline is more effective than the conservative technique in the treatment of juvenile periodontitis, although both gave improvement.

Etidronate 200 mg daily was administered to four female patients with periodontitis and resultant alveolar pyorrhoea for periods of 2 weeks, followed by off-periods of 10 weeks or more, for 2-3 years. The macroscopic appearance of gingival mobility of the teeth, depth of periodontal pockets, and X-ray findings of alveolar bones improved markedly during this time. The effects were first observed after 6-12 months of treatment. These findings indicate that bisphosphonates may be effective in the treatment of periodontitis and resultant alveolar pyorrhoea. The effect may be mediated by the inhibitory action on bone resorption and the anti-inflammatory action of etidronate. Concomitant conventional dental management is also required.

The objective of this study was to evaluate the application of an enamel matrix derivative (Emdogain) in deep periodontal pocket therapy. Twenty-one patients presenting intrabony and interproximal defects that could be treated with guided tissue regeneration were selected. The intrabony defects were divided into deep (< 9 mm) and very deep (> or = 9 mm) defects. Bleeding on probing, Plaque Index, probing pocket depth, mobility index, gingival recession, probing attachment level, and surgical bone level were measured at baseline. At 12 months, cases were reexamined and indices recorded again. The mean probing depth decreased from 8.1 +/- 2.1 mm to 3.2 +/- 1.5 mm; attachment level decreased from 10.4 +/- 2.4 mm to 7.0 +/- 1.8 mm; recession increased from 2.3 +/- 1.4 mm to 3.8 +/- 1.8 mm; and surgical bone level decreased from 9.6 +/- 1.9 mm to 7.1 +/- 1.5 mm. No significant difference wa noted between bone defects with one or 2 walls, between local and generalized periodontitis, or between smokers and nonsmokers. Significant statistical difference was found, however, between deep intrabony defects and very deep defects when attachment gain was considered. No adverse reaction to the substance was noted. The good clinical results obtained were not confirmed by radiologic results; standardized and computerized radiographs at 12 months did not reveal significant improvement. The histologic examination carried out on 2 samples did not show evidence of new attachment. Further studies are necessary to clarify the action mechanism and to evaluate the long-term results of this method.

Bruxism is responsible for occlusal tooth wear but can not induce nor aggravate gingivitis or periodontitis. Bruxism induces jiggling forces, which cause a clinical tooth hypermobility, radiologically seen as a widened periodontal space. Although there is no direct causal relation between bruxism and implant failure, implant overload may lead to fractures of the components and bone loss.

This paper presents the dental findings of a child with the oculocerebrorenal syndrome of Lowe. The genetic abnormality in this condition results in an inborn error of inositol phosphate metabolism. Renal tubular dysfunction leads to metabolic acidosis and phosphaturia. At 4 years, generalised mobility of all primary teeth was noted. It is postulated that a defective inositol phosphate metabolism was responsible for the periodontal pathology found in this case. This is in direct contrast with previous reports of prolonged retention of primary teeth in children with this condition. Histology of extracted primary incisors demonstrated enlarged pulp chambers and mildly dysplastic dentin formation. This is consistent with a chronic subrachitic state, a known feature of Lowe syndrome, but no prominent interglobular dentin was present.

An evaluation of 96 treated orthodontic patients with maxillary median diastema ranging from 0.50 mm to 5.62 mm (mean 1.22, SD 0.85) was performed 4.0 to 9.0 years after completion of active treatment. Pre- and posttreatment data were gathered from available records. Follow-up data were gathered from records and interviews of 37 patients, and from phone interviews of 59 patients. The incidence of diastema relapse was 49% when scored as either presence of a measurable space at follow-up, a history of orthodontic or prosthetic retreatment to close a reopened space, or continued use of a retainer to control relapse tendency. Logistic regression analysis revealed that pretreatment diastema size and presence of a family member with a similar condition were the only significant risk factors for relapse (p<0.05), while pretreatment spacing in the maxillary anterior dentition approached significance (p = 0.10). No association was found between relapse and presence of an abnormal frenum or an osseous intermaxillary cleft, although patients with an abnormal frenum had a wider pretreatment diastema than those with a normal frenum (p<0.05). Fremitus of the maxillary incisors was the only parameter at follow-up associated with space reopening (p<0.01).

Bone lesions in the maxilla have rarely been described in relation to sarcoidosis. This patient exhibited many of the classic signs of sarcoidosis, including lack of symptoms at the time of presentation, which resulted in the diagnosis of sarcoidosis being made serendipitously. The presence of musculoskeletal lesions is often regarded as a poor prognostic sign and, in general, sarcoidosis follows a more virulent course in black patients. Sadly, the course of the disease in this patient continues to march onward despite a 1-year therapeutic trial of corticosteroids.

Two cases of Papillon-Lefèvre syndrome, a rare hereditary affection of unknown etiology, whose clinical signs are hyperkeratosis palmoplantaris and parodontitis, are described. The results obtained with the ultrastructural examination of the lesions are shown. A therapeutic protocol which can reduce the evolution of the pathology, is also suggested.

The purpose of this study was to compare the repair response of bioactive glass synthetic bone graft particles and open debridement in the treatment of human periodontal osseous defects. Fifty-nine defects in 16 healthy adults were selected. Each patient had at least 2 sites with attachment loss of at least 6 mm with clinical and radiographic evidence of intrabony or furcation defects. One to 3 months after cause-related therapy (oral hygiene instructions, scaling and root planing), the following measurements were recorded prior to surgery: probing depths, clinical attachment level, and gingival recession. Each defect was surgically exposed and measurements made of the alveolar crest height and base of osseous defect. The test defects were implanted with bioactive glass. The other sites served as unimplanted controls. Flaps were sutured at or close to the presurgical level. Radiographs and soft tissue presurgical measurements were repeated at 6, 9, and 12 months. At 12 months all sites were surgically re-entered to record osseous measurements. At the 12-month evaluation, significantly greater mean probing depth reduction was noted in the bioactive glass group compared to the controls (4.26 mm versus 3.44 mm; P = 0.028). Clinical attachment level gain was significantly improved (P = 0.0004) in the bioactive glass sites (2.96 mm) compared to the control sites (1.54 mm). There was significantly less gingival recession in the bioactive glass sites (1.29 mm) compared to the control sites (1.87 mm). Defect fill was significantly greater in the bioactive glass sites (3.28 mm) compared to the control sites (1.45 mm). Defect depth reduction was significantly greater in the bioactive glass sites (4.36 mm) compared to the control sites (3.15 mm). In conclusion, bioactive glass showed significant improvement in clinical parameters compared to open flap debridement.

A family is reported with dentinal dysplasia type I affecting both dentitions. Presenting features included unusual mobility of the teeth, followed by early exfoliation; normal clinical shape of the crowns of the teeth, but with an amber color without any sign of attrition or abnormal loss of enamel. Radiographic findings showed pulp-chamber and root-canal obliteration, poor root formation, radiolucent linear appearance of the pulp chamber parallel to the cementoenamel junction and frequent periapical radiolucencies. Histological studies have reported large masses of calcified tubular dentin, atypical osteodentin, and also true denticle.

The aim of this study was to evaluate the clinical criteria for classification of 2 different patient groups. From retrospective comparisons of pocket probing depth (PPD) charts, we classified 22 patients as either non-responding or responding to periodontal treatment. The non-responding patient group, in comparison with the responding patient group, showed a profile over time of less PPD reduction in response to periodontal treatment. Information registered in each patient's file regarding clinical periodontal conditions, as well as treatment procedure characteristics, was gathered. Bivariate analyses were performed. 3 clinical variables (frequency of mean PPD > or = 6 mm during the treatment period; at final registration; and the mobility score at the final registration) indicated that 2 separate patient groups had been identified. Although the patient groups exhibited advanced periodontitis at the beginning of treatment, both groups at the end of treatment had lost very few (1-2) teeth, probably as a result of regular supportive treatment. The characteristics of the selected clinical criteria warrant the use of these 2 patient groups in further analysis of the relation of psychosocial stress and microbiological characteristics of therapy-resistant periodontitis.

Two case reports illustrate spontaneous correction of pathologic migration following periodontal therapy. In one case, the displaced teeth were repositioned without orthodontic appliances after nonsurgical and surgical periodontal treatment. In the other case, closure of a diastema occurred following only nonsurgical therapy. The predictability of these findings needs further investigation. A discussion of possible reasons for this type of tooth movement is included.

Access surgery may be recommended to about 80% of patients who present with advanced forms of periodontal disease. In this report, a multivariate logistic regression analysis which incorporated several clinical parameters for each tooth examined, i.e., tooth type, furcation involvement, bleeding on probing, attachment level, probing depth, mobility and BANA test score, was conducted using generalized estimating equations (GEE). This approach identified parameters that were significantly associated at p < 0.05 level with the need for access surgery or extraction for periodontal purposes. The estimated probabilities derived from the GEE model were plotted over the complete spectrum of operating conditions to obtain a receiver-operator characteristic (ROC) curve. At a probability cutpoint of 0.8, the decision threshold for surgery/extraction at the pretreatment examination would have a sensitivity of 76.1% and a specificity of 75.3%. We have taken this 0.8 cut point to look at specific clinical decisions made by our examiners after the patients had received scaling and root planing plus 2 weeks unsupervised usage of systemic antimicrobials. The clinicians' decision was taken as the primary reference standard. The model's estimated decision agreed with the clinicians' decision in 226 of the 284 teeth, for an accuracy of 80%. The specificity was 90% and the sensitivity was 43%.

Calcium phosphates are widely used as biomaterials. Ultrastructural assessments are of the utmost importance in our understanding of interfacial phenomena. The aim of this study was to learn more about the newly formed crystal growth mechanisms. The interfaces between implanted synthetic hydroxyapatite crystals (HAS) and newly formed crystallites were thoroughly examined on a molecular level. The bone-grafting material (HAS) was implanted into two adult patients, and small biopsies were recovered 6 months after implantation. The raw biomaterial was analyzed by x-ray diffraction and high-resolution transmission electron microscopy (HRTEM). Six months after their implantation, the HAS aggregates were surrounded by a mineralized bone matrix. Tiny crystallites also filled the spaces between the HAS crystals within the aggregates. These newly formed crystallites growing at the surfaces of the implanted HAS crystals appeared to be apatitic. The crystallographic investigations of the nucleation and growing mechanisms of the newly formed crystallites were performed by HRTEM in association with computer simulation and mathematical processing of digitized images. A relationship was noted between the orientation axes of crystallites growing nearby and the zone axes of the implanted HAS, thus strongly suggesting a guiding or substratum role of the HAS particles.

We have studied the peripheral blood lymphocyte populations in our 6 patients (2 female and 4 male) with a mean age of 11.19 with Papillon-Lèfevre Syndrome (PLS) using adequate monoclonal antibodies and double coloured flow cytometry. Total B, T, CD4, CD8, CD29, CD45RA, NK, HLA-DR cells were studied. Total B, T, CD4 and CD8 lymphocytes were within normal limits. We have observed an increase in the CD29 lymphocytes and NK cells and a decrease in CD45RA lymphocytes. We think that these findings are important in explaining B lymphocyte activation and in the pathogenesis of the PLS.

The purpose was to evaluate the use of demineralized freeze-dried bone allograft reconstituted with 50 mg/ml tetracycline hydrochloride in the treatment of intrabony periodontal defects. Fifteen systemically healthy patients (12 females, 3 males; aged 35 to 61) with moderate-advanced periodontitis were treated. Patients had 3 osseous defects with probing depths (PD) > 5 mm after initial therapy. Each site in each subject was randomly assigned to one of the following groups: 1) demineralized freeze-dried bone allograft reconstituted with 50 mg/ml tetracycline (DFDBA + TCN); 2) demineralized freeze-dried bone allograft alone (DFDBA); or 3) debridement only (D). Clinical measurements were taken the day of surgery, 6 months, and 1 year. Standardized radiographs were taken at baseline and 1 year and were evaluated by computer assisted densitometric image analysis (CADIA). Clinical measurements included gingival recession, PD, clinical attachment level, and mobility. Osseous defect measurements were taken at baseline and at the 1 year reentry. No adverse healing responses occurred. The results showed that all patients had a statistically significant improvement in probing depth and attachment level at 1 year. Osseous measurements showed bone fill of 2.27 mm (51.6%) for the DFDBA + TCN group, 2.20 mm (52.4%) for the DFDBA group, and 1.27 mm (32.8%) for the D group. Defect resolution was 77.3% for the DFDBA + TCN group, 77.9% for the DFDBA group, and 63.8% for the D group. The mean CADIA values were 5.04 for the DFDBA + TCN group, 6.79 for the DFDBA group and 2.78 for the D group. The CADIA values did not correlate with the clinical parameters. Although the grafted groups showed greater bone fill and defect resolution, there was no statistically significant difference in any of the clinical parameters between the treatment groups. This study suggests that there is no significant benefit from reconstituting the allograft with 50 mg/ml of tetracycline hydrochloride.

A group of 19 patients where traumatic root fractures were treated with surgical extrusion procedure has been clinically and radiographically followed up for 10 years. Except for one out of 21 intraalveolar transplanted roots all functioned with different kinds of crown restorations and without pathological complications. The surgical extrusion method should thus be a useful tool in the treatment of teeth with cervical root-fractures and also teeth with deep cervical root caries which are difficult to treat conservatively.

The aims of the present study were to analyze (i) which tissue changes may occur in the zone of co-destruction to better understand why trauma from occlusion may induce additional attachment loss, and (ii) whether changes occur in the periodontal ligament tissue when an inflammatory lesion (ICT) approaches the periodontal ligament space. 16, 1-year-old beagle dogs, were selected and divided into 2 groups, group A and group B, consisting of 6 and 10 dogs, respectively. In group A, on day 0, a bucco-lingual jiggling type movement was induced resulting in increasing tooth mobility at P3 (test tooth) by the application of an orthodontic elastic which traversed the buccal surface of the crown of the test tooth. The elastic was exchanged either in a buccal or in a lingual position 2x a week during a 3-month period. 3P served as non-jiggled control tooth. Tooth mobility measurements were recorded on days 0, 30, 60, 90. A plaque control regimen was maintained until the end of the experiment (day 90). On day 90, biopsies including P3 and 3P were harvested. The dogs representing group B, were divided into 2 subgroups of 5 each, group BI and group BII. On day 0, a 4-month period of experimental periodontal tissue breakdown was initiated by placing cotton floss ligatures submarginally around the mandibular fourth premolars (4P4) in group BI and around the mandibular third premolars GP3) in group BII. All ligatures were exchanged, replaced 1x every month, and on day 120 permanently removed. On the same day, biopsies included 4P4 were harvested. Following supragingival debridement 3P3 were allowed to accumulate plaque until the end of the study (day 225). On this occasion, biopsies including 3P3 were harvested. The results of the histological measurements revealed that in the most coronal portion of the periodontal ligament of teeth exhibiting increasing mobility, there was an increased width, a reduced % tissue volume of collagen, and an increased volume of vascular structures and leukocytes. Furthermore, the number of osteoclasts bordering this portion of the alveolar bone was increased and the number of collagen fibers inserting into the root cementum and into the alveolar bone was reduced. It was also demonstrated that in teeth with normal mobility, the position of the gingival ICT failed to influence the composition of the tissue within the coronal portion of the periodontal ligament.

The aim of this study was to compare the clinical regenerative capacity of collagen membrane with and without demineralized freeze-dried bone allografts (DFDBA) in treating periodontal intrabony defects. Ten systemically healthy patients with similar bilateral periodontal defects were scheduled for surgery. Each patient had at least > or = 6 mm clinical probing depth and loss of attachment at selected sites. Baseline measurements included gingival index (GI), plaque index (PI), gingival recession (GR), clinical attachment level (CAL), probing depth (PD), and mobility. At the time of surgery, the defects were randomly assigned to either test (collagen membrane plus DFDBA) or control group (collagen membrane only). Stent to base of the defects, stent to crest bone, crest of bone to base of the defect, and width of the defects were recorded at the time of surgery and reentry. Eight patients returned after 6 months for reentry surgery. Statistical analysis with a paired t test was used to evaluate the treatment effect and comparison between test and control groups. In addition, a McNemar test was used to analyze the significance of GI, PI, and mobility at different times. The result of this study indicated that both the collagen plus DFDBA and the collagen alone treatment groups had a significant decrease of PD (3.4 +/- 0.4 and 3.2 +/- 0.4 mm), gain of CAL (2.3 +/- 0.5 and 2.0 +/- 0.4 mm), and defect fill (1.7 +/- 0.3 and 1.9 +/- 0.9 mm) (P < 0.05) when compared to the presurgery status. However, there was no significant difference in PD, AL, GR, defect fill, crestal bone resorption, GI, PI, or mobility between the test group and control group. No adverse tissue reaction, infection, or delayed wound healing was noted throughout the treatment in either group. This study suggests that the collagen membrane is well tolerated by the human tissues. Both treatments, either collagen membrane plus DFDBA or collagen membrane alone, promoted significant resolution of periodontal intrabony defects. The addition of a bone graft (DFDBA) with a collagen membrane appears to add no extra benefit to the collagen membrane treatment.

The actual length of clinically exposed tooth structure between planned restoration margin and alveolar crest ("biologic width") obtained during surgical crown elongation procedures was compared to the textbook goal of 3.0 mm. Sixteen (16) patients with 21 teeth requiring surgical crown lengthening for restoration placement participated. Oral hygiene instructions were given and optimal plaque control was mandatory. At each clinician's discretion, surgical techniques consisted of either gingivectomy or an apically positioned flap with and without osseous resection. Utilizing a reference stent, measurements were obtained at the facial, mesial-facial, lingual, and distal-lingual of the treated teeth both before and after osseous reduction. Parameters evaluated were gingival margin position, probing depth, mucogingival junction position, alveolar crest location, mobility, plaque index, and gingival index. These measurements were again recorded 8 weeks after surgery with the exception of alveolar crest. Statistical analysis with the paired t-test and linear correlation showed no significant change from baseline or among operators with varying experience in any of these parameters. Overall the results showed that the default objective of 3 mm between planned restoration margin and alveolar crest was not routinely achieved (mean 2.4 +/- 1.4 mm). The post-treatment distance from the planned restoration margin to the alveolar crest was greatest at the facial aspect of the teeth (mean 2.6 +/- 1.2 mm) and least at the distal-lingual (mean 2.2 +/- 1.7 mm). In addition, although more experienced periodontists removed a larger amount of bone, the amount of root surface exposed was still short of the initially desired biologic width.(ABSTRACT TRUNCATED AT 250 WORDS)

Successful management of a tooth that has sustained a transverse root fracture depends on three major factors: the position of the fracture line, the extent of mobility of the coronal segment, and the state of the pulpal tissue. The position of the fracture line and its relationship to the base of the gingival crevice are the most important factors in determining the long-term prognosis for the tooth.

The aim of the present experiment was to study alterations in the mobility of teeth that occurred during resolution of experimentally induced periodontitis lesions in the dog. 5, 1-year-old, beagle dogs were used in the study. The left and right 4th, 3rd, and 2nd mandibular premolars (4P4, 3P3, 2P2) served as experimental teeth. Periodontal tissue breakdown was initiated by placing plaque-collecting cotton-floss ligatures around the neck of the experimental teeth. The ligatures were replaced to the level of the receding gingival margin 1 x every month. On Day 120, the ligatures were removed and debridement was performed. A groove, parallel to the long axis of the mesial root, was prepared in the mesio-buccal surface of the crowns of 2P and P2. Guided by the groove and with a probing force of 0.5 N, a probe was inserted into the buccal gingival pocket of the mesial root and was attached to the buccal surface. Biopsies including both the mesial and distal root of 2P and P2 and the surrounding hard and soft tissues were harvested. The biopsy procedure was repeated in a similar manner 15 days (i.e. Day 135) and 3 months (i.e. Day 225) after ligature removal in the 4th (4P4) and 3rd (3P3) premolar regions. After fixation, decalcification and sectioning, the biopsy material was exposed to histometric and morphometric measurements. Assessment of the mobility of the experimental teeth was performed on Days 120, 135 and 225 using the Periotest system.(ABSTRACT TRUNCATED AT 250 WORDS)

The upper first molars of adult male rats were moved for 7 days and unfixed, undecalcified frozen sections of the molar periodontal ligament were prepared and observed. The upper jaws of the rats were immersed rapidly in liquid nitrogen and sectioned with a cryostat using a super hard knife. Five micrometer serial sections were cut, collected, freeze-dried and observed with both light and scanning electron microscopy. Electron probe microanalysis (EPMA) was also performed on the sections. On the tension side of the periodontal ligament, periodontal fibers were stretched and the osteoblasts were aligned on the osteoid, which showed metamasia with the toluidine blue stain. On the pressure side where the periodontal ligament was extremely compressed, tissue degeneration was caused by tooth movement and the osteoclasts were observed on the bone surface adjacent to the degenerating tissues. Scanning electron microscopy revealed a network arrangement of the collagen fiber bundles on the tension side, but not on the pressure side of the periodontal ligament. The spectrum obtained from EPMA of the osteoid demonstrated X-ray (Ka) peaks of Na, P, S, K and Ca.

The aim of the present investigation was to assess the resistance offered by the gingiva at teeth and the peri-implant mucosa at osseointegrated titanium implants to mechanical probing. 5 beagle dogs were used in the experiment. The 2nd and 3rd premolars and the 1st molars of the right and left mandibular dentition were extracted. 2 titanium implants were installed in the edentulous right and left premolar- and molar-regions. Abutment connection was performed 3 months later. The remaining premolar in the left jaw (P4) was exposed to "experimental periodontitis" during a 4-month period and, thus, the 4th premolar in the right jaw (4P) was representing healthy periodontium. The inflamed soft tissues at P4 were treated using a flap procedure. Following 2 weeks of healing, the main experiment was started, i.e., day 0. During the subsequent 360 days, the teeth and abutment parts of the implants were regularly exposed to plaque control (3 x/week). Radiographs of 4P-, P4- and the implant-regions were obtained on days 0 and 360. Mobility measurements were performed on days 0 and 360. Biopsies of the experimental teeth and the implants were sampled at the end of the study. The results of the present experiment demonstrated that differences in terms of tissue composition, organization and attachment between the gingiva and the root surface on one hand and between the peri-implant mucosa and the implant surface on the other, make the conditions for probing depth measurements at teeth and implants different.(ABSTRACT TRUNCATED AT 250 WORDS)

Two groups of elderly chinese were selected from a large epidemiological sample on the basis of a low ("best" group) or a high ("worst" group) number of sites with attachment loss levels > or = 6 mm and/or pocket depth > or = 4 mm and at least 16 teeth present. Six years later the patients were clinically reexamined and the subgingival microflora was assessed. This paper presents the clinical characteristics of destructive periodontal disease progression among the two subgroups. The "best" group lost an average of 1.8 teeth, contrasting the average loss of 5.3 teeth among the "worst" group. Virtually all teeth lost among the "worst" group had a baseline attachment loss level > or = 4 mm, in contrast to 48% among the "best" group. While dental caries could be identified as a cause of tooth loss in both groups, the excess tooth loss among the "worst" group seems attributable to periodontal destruction. The average of 1.21 mm attachment/site lost among the "best" group was not statistically significantly different from the 1.36 mm/site lost among the "worst" group during the 6 years. Individual mean losses of attachment ranged from a gain of 0.03 mm to a loss of 3.19 mm. An attachment loss > or = 2 mm at a site was highly positively associated with a high initial attachment loss level (> or = 4 mm) at that site among the "best" group, whereas a highly negative association was seen among the "worst" group.(ABSTRACT TRUNCATED AT 250 WORDS)