Professional competencies and work-related support in relation to periodontal therapy and work satisfaction: A questionnaire study among Swedish Dental Hygienists

OBJECTIVES

To analyse dental hygienists' (DHs) views on professional competencies and behavioural interventions in the treatment of periodontitis patients, perceived work-related support and work satisfaction.

METHODS

A Web-based questionnaire was distributed to all DHs employed at the public dental service in the county of Västra Götaland, Sweden. 302 (83%) responded to the questionnaire; 291 of these DHs stated that they on regular basis treated periodontitis patients and thus constituted the sample for analyses. Based on initial correlation and bivariate analyses of the questionnaire data, multiple logistic regression models were formulated to estimate perceived competencies to treat patients with periodontitis and work satisfaction.

RESULTS

The multiple analyses revealed that DHs who worked with specific methods for behavioural intervention, like motivational interviewing, were more likely to rate themselves as "definitely possessing the competencies required to treat patients with periodontitis" (OR 4.0). Likewise, this group of DHs did not consider it more difficult to charge their patients the financial costs for such a behavioural intervention than for scaling therapy (OR 3.1). The perception that one's professional competencies were utilized well in daily practice was associated with high work satisfaction (OR 4.1). More years in the profession (OR 1.03) and a good support by colleagues (OR 1.9) had also a positive impact on work satisfaction.

CONCLUSIONS

Dental hygienists' considered that competencies in the treatment of periodontitis patients were related to the practice of behavioural interventions as part of therapy. A stimulating and supportive work environment, with opportunities for professional development, is important for work satisfaction.

Effectiveness of implant therapy analyzed in a Swedish population: early and late implant loss

Treatment outcomes in implant dentistry have been mainly assessed as implant survival rates in small, selected patient groups of specialist or university clinical settings. This study reports on loss of dental implants assessed in a large and randomly selected patient sample. The results were aimed at representing evaluation of effectiveness of implant dentistry. Using the national data register of the Swedish Social Insurance Agency, 4,716 patients were randomly selected. All had been provided with implant-supported restorative therapy in 2003. Patient files of 2,765 patients (11,311 implants) were collected from more than 800 clinicians. Information on patients, treatment procedures, and outcomes related to the implant-supported restorative therapy was extracted from the files. In total, 596 of the 2,765 subjects, provided with 2,367 implants, attended a clinical examination 9 y after therapy. Implant loss that occurred prior to connection of the supraconstruction was scored as an early implant loss, while later occurring loss was considered late implant loss. Early implant loss occurred in 4.4% of patients (1.4% of implants), while 4.2% of the patients who were examined 9 y after therapy presented with late implant loss (2.0% of implants). Overall, 7.6% of the patients had lost at least 1 implant. Multilevel analysis revealed higher odds ratios for early implant loss among smokers and patients with an initial diagnosis of periodontitis. Implants shorter than 10 mm and representing certain brands also showed higher odds ratios for early implant loss. Implant brand also influenced late implant loss. Implant loss is not an uncommon event, and patient and implant characteristics influence outcomes (ClinicalTrials.gov NCT01825772).

Patient satisfaction with mini-implant stabilised full dentures. A 1-year prospective study

The purpose of this study was to evaluate patient-centred outcomes with regard to function and comfort after placement of mini-implants for stabilisation of complete dentures. The trial was designed as a prospective cohort of 12-months duration and involved 21 subjects in the age of 50-90 years having a full denture in the maxilla or the mandible with poor stability during function. Flapless installation of 2-4 narrow-body Dentatus Atlas(®) implants was performed and retention for the existing denture was obtained by the use of a silicone-based soft lining material (Tuf-Link(®)). Patients' judgement of perceived satisfaction with function and comfort of the dentures was recorded at baseline, 1- and 12-months post-treatment using 10-centimetre visual analogue scales (VAS) and a questionnaire. Clinical examination of the conditions of the peri-implant soft tissues was performed at 12 months. Nineteen of the 21 patients were available for the 12-month follow-up examination. The two drop-out subjects lost all implants within 1 month and rejected retreatment. Further six subjects lost 1-2 implants, but were sucessfully retreated by insertion of new implants. Overall satisfaction, chewing and speaking comfort were all markedly improved from pre-treatment median VAS scores of around 4-5 to median scores of 9·0-10 (10 = optimal) at the final examination. The prevalence of positive answers to questions regarding stability/function of the denture increased significantly to almost 100% for all questions. Treatment involving maxillary dentures and the use of short implants (7-10 mm) was associated with an increased risk of implant failure. The results indicate that placement of mini-implants as retentive elements for full dentures with poor functional stability has a marked positive impact on the patients' perception of oral function and comfort as well as security in social life.

Dental hygienists' views on communicative factors and interpersonal processes in prevention and treatment of periodontal disease

OBJECTIVE

The aim of this study was to explore views of DHs on communicative issues and interpersonal processes of importance in the prevention and treatment of periodontal disease.

METHOD

The qualitative method of Grounded Theory (GT) was chosen for data sampling and analysis. Audio-taped and open-ended interviews were conducted with 17 dental hygienists. The interviews were transcribed verbatim and analysed in a hierarchical coding process, according to the principles of GT.

RESULT

In the analysis a core category was identified as 'to be successful in information and oral health education and managing desirable behavioural changes'. The core concept was related to four additional categories and dimensions; (i) 'to establish a trustful relationship with the patient', (ii) 'to present information about the oral health status and to give oral hygiene instructions', (iii) 'to be professional in the role as a dental hygienist' and (iv) 'to have a supportive working environment in order to feel satisfaction with the work and to reach desirable treatment results'.

CONCLUSION

The results describe a psychosocial process that elucidates the importance of building a trustful relationship with the patient, feeling secure in one's professional role as a DH and last but not least, the importance of having support from colleagues and the clinical manager to be successful in the prevention and treatment of periodontal diseases.

Relative effectiveness of powered and manual toothbrushes in elderly patients with implant-supported mandibular overdentures

AIM

The aim of this study was to compare the clinical effectiveness of a powered toothbrush (Braun Oral-B Plaque Remover 3-D) and a manual soft toothbrush (Oral-B Squish-grip brush) for the control of supragingival plaque and soft tissue inflammation around implants supporting mandibular overdentures.

MATERIAL AND METHODS

The study sample involved 40 edentulous subjects, aged 55-80 years, having 2 unsplinted mandibular implants supporting a complete removable overdenture opposed by a maxillary complete denture. In this single-blinded, randomised, cross-over clinical trial, two 6-week experimental phases were separated by a 2-week wash-out period. 2 weeks prior to each experimental phase (pre-entry visits), implant abutments were polished to remove all plaque and a standardised instruction in the use of the toothbrush was given. Modified plaque and bleeding indices were recorded at the start and end of each experimental period. Mean index scores at each phase were analysed using paired t-test, and the mean number of sites showing a change in plaque or mucositis were compared using the Mann-Whitney U-test. Combined data from 2 different implant systems were considered after controlling for implant type.

RESULTS

Only minor changes in plaque and bleeding scores were observed following the two test periods. There were no statistically significant differences between the manual and powered toothbrushes.

CONCLUSION

Manual and powered brushes were found to be of comparable efficacy with regard to improvement in peri-implant bleeding and plaque indices.

Utilisation of locally delivered doxycycline in non-surgical treatment of chronic periodontitis. A comparative multi-centre trial of 2 treatment approaches

AIM

In the present 6-month multicentre trial, the outcome of 2 different approaches to non-surgical treatment of chronic periodontitis, both involving the use of a locally delivered controlled-release doxycycline, was evaluated.

MATERIAL AND METHODS

105 adult patients with moderately advanced chronic periodontitis from 3 centres participated in the trial. Each patient had to present with at least 8 periodontal sites in 2 jaw quadrants with a probing pocket depth (PPD) of > or =5 mm and bleeding following pocket probing (BoP), out of which at least 2 sites had to be > or =7 mm and a further 2 sites > or =6 mm. Following a baseline examination, including assessments of plaque, PPD, clinical attachment level (CAL) and BoP, careful instruction in oral hygiene was given. The patients were then randomly assigned to one of two treatment groups: scaling/root planing (SRP) with local analgesia or debridement (supra- and subgingival ultrasonic instrumentation without analgesia). The "SRP" group received a single episode of full-mouth supra-/subgingival scaling and root planing under local analgesia. In addition, at a 3-month recall visit, a full-mouth supra-/subgingival debridement using ultrasonic instrumentation was provided. This was followed by subgingival application of an 8.5% w/w doxycycline polymer at sites with a remaining PPD of > or =5 mm. The patients of the "debridement" group were initially subjected to a 45-minute full-mouth debridement with the use of an ultrasonic instrument and without administration of local analgesia, and followed by application of doxycycline in sites with a PPD of > or =5 mm. At month 3, sites with a remaining PPD of > or =5 mm were subjected to scaling and root planing. Clinical re-examinations were performed at 3 and 6 months.

RESULTS

At 3 months, the proportion of sites showing PPD of < or =4 mm was significantly higher in the "debridement" group than in the "SRP" group (58% versus 50%; p<0.05). The CAL gain at 3 months amounted to 0.8 mm in the "debridement" group and 0.5 mm in the "SRP" group (p=0.064). The proportion of sites demonstrating a clinically significant CAL gain (> or =2 mm) was higher in the "debridement" group than in the "SRP" group (38% versus 30%; p<0.05). At the 6-month examination, no statistically significant differences in PPD or CAL were found between the two treatment groups. BoP was significantly lower for the "debridement" group than for the "SRP" group (p<0.001) both at 3- and 6 months. The mean total treatment time (baseline and 3-month) for the "SRP" patients was 3:11 h, compared to 2:00 h for the patients in the "debridement" group (p<0.001).

CONCLUSION

The results indicate that simplified subgingival instrumentation combined with local application of doxycycline in deep periodontal sites can be considered as a justified approach for non-surgical treatment of chronic periodontitis.

Root-dentin sensitivity following non-surgical periodontal treatment

BACKGROUND, AIMS

Little clinical data exist on the incidence and severity by which root dentin sensitivity (RDS) results from periodontal therapy. The aim of the present clinical trial was to study the degree to which a sample of patients requiring non-surgical periodontal treatment develops RDS.

MATERIAL AND METHODS

Alterations in RDS was followed in 35 patients (29-65 years of age) requiring non-surgical treatment for moderate to advanced periodontal disease. Inclusion criteria for participation were need for periodontal treatment in at least 2 quadrants comprising a minimum of 4 teeth with vital pulps, no open caries lesions, no dental treatment in the last 3 months and no ongoing treatment for RDS. Baseline and follow-up recordings included responses of teeth to pain stimuli (directed compressed air) at buccal surfaces as graded by the patient on a 10-cm visual analogue scale (VAS). Periodontal therapy consisted of oral hygiene instruction (OH) followed by supra- and subgingival scaling/root planing by hand and ultrasonic instrumentation of one quadrant per each of the subsequent weeks. Thus, follow-up data included pain assessment after 1-3 weeks of OH alone, and 1-4 weeks post-instrumentation.

RESULTS

There was a statistically significant reduction in mean VAS scoring over time in quadrants where only meticulous plaque control had been maintained, while VAS mean values increased significantly after instrumentation (p<0.001). Also the % of subjects reporting higher mean VAS values increased after instrumentation. Changes in mean VAS scores were generally moderate and only 9 patients gave an increase on VAS of >2 cm for 3 or more teeth. A statistically significantly higher increase of RDS was observed for initially sensitive teeth (VAS>0) than for teeth not responding at baseline (p<0.001). Although a reduction in the intensity of RDS could be noticed during the later phase of the 4-week follow-up period after scaling and root planing, the percentage of sensitive teeth remained unchanged.

CONCLUSION

The data confirm that meticulous plaque control will diminish RDS problems and that scaling and root planing procedures in periodontal therapy result in an increase of teeth that respond to painful stimuli. However, pain experiences in general appeared minor and only a few teeth in a few patients developed highly sensitive root surfaces following instrumentation.

Periodontal treatment decisions for molars: an analysis of influencing factors and long-term outcome

BACKGROUND

The purpose of this retrospective study was 1) to analyze factors influencing the treatment decision for periodontitis-affected molars and 2) to evaluate the long-term outcome of the decision. The treatment alternatives included in the analysis were maintenance of the tooth with only non-surgically/surgically performed scaling/root planing with or without furcation plasty, root separation/resection, and tooth extraction.

METHODS

Data collected from a total of 1,313 first and second molars in 222 patients (mean age 45 years; range 14 to 73 years), referred for periodontal treatment, were analyzed with respect to treatment decisions for furcation-involved teeth. The patients had been examined with respect to oral hygiene status, gingival conditions, probing depth, furcation involvement, and radiographic bone height before and after active periodontal treatment. Frequencies, mean values and standard deviations were calculated for the various variables assessed. Multiple regression models were formulated in order to analyze the influence of various variables on treatment decisions. One-hundred and sixty (72%) of the patients agreed to participate in a follow-up examination to determine the clinical and radiographic status of the molars 8 to 12 years after the active phase of treatment for evaluation of the long-term outcome of the treatment decision.

RESULTS

Twenty-eight percent of the molars were extracted and 4% were root separated/resected. Factors found to significantly influence the decision of tooth extraction were tooth mobility, tooth position, lack of occlusal antagonism, degree of furcation involvement, and remaining bone support. Of the factors analyzed with respect to root separation/resection, molar position and degree of furcation involvement showed the strongest influence on the treatment decision. The 8- to 12-year follow-up examination revealed that 96% of the molars subjected to non-resective therapy were still in function. The corresponding figure for root separated/resected molars was 89%. Loss of radiographic bone support during the 10-year follow-up period was 0.1 to 0.6 mm for the various molars with the highest value for maxillary second molars.

CONCLUSIONS

A conservative approach to the treatment of molars with even deep furcation invasions may show a high long-term success rate, provided maintenance care is offered.

Esthetic outcome of implant-supported single-tooth replacements assessed by the patient and by prosthodontists

PURPOSE

The objective of this study was to assess and compare patients' and clinicians' judgments of the esthetic outcome of implant-supported single-tooth replacements.

MATERIALS AND METHODS

In all, 29 patients with 41 single implant-supported crowns in the maxillary anterior region participated in the study. The esthetic outcome of the implant-supported crowns was assessed by the patients and by 5 prosthodontists by means of a questionnaire in which various esthetics-related variables were addressed and responded to using visual analogue scales. Multiple regression analyses were used to evaluate the influence of the variables on the "overall satisfaction" with the implant-supported crown.

RESULTS

Most variables in the patients' assessments revealed mean values above 90% and median values close to 100%. No single factor used in the multiple regression analysis was found to influence a patient's satisfaction with appearance of the crown at a statistically significant level. The clinicians' degree of satisfaction was for all variables lower than that of the patients. In 89% of the cases the clinicians could correctly locate the single implant-supported crown. Among the variables assessed, surrounding soft tissue appearance and form of the crown had the strongest influence on the clinician's overall satisfaction with the appearance of the crown.

CONCLUSION

Appreciation of the esthetic outcome of the single implant-supported crowns was rated higher by the patients than by the prosthodontists. Furthermore, factors considered by professionals to be of significance for the esthetic result of the restorative treatment may not be of decisive importance for the patient's satisfaction.

Implant supported single-tooth replacements compared to contralateral natural teeth. Crown and soft tissue dimensions

The aim of this study was to make a comparative evaluation of crown and soft tissue dimensions between implant-supported single-tooth replacements and the contralateral natural tooth. Twenty patients, who had been treated with an implant-supported single-tooth replacement in the esthetic zone of the maxillary jaw and had i) a non-restored contralateral natural tooth and ii) completed the implant-supported crown restoration at least 6 months prior to the scheduled follow-up examination, were included in the study. At the re-examination various variables describing crown form, soft tissue dimensions and soft tissue conditions were assessed. In addition, the patient's overall satisfaction with the esthetic outcome of the implant-supported single crown was scored using a Visual Analogue Scale (VAS). In 12 of the subjects clinical photographs were available from the time of crown insertion for evaluation of longitudinal alterations of the papilla height. The results revealed that, in comparison to the contralateral natural crown, the implant supported crown i) was longer, ii) had a smaller facio-lingual width, iii) was bordered by a thicker facial mucosa, iv) had a lower height of the distal papilla, v) showed a higher frequency of mucositis and bleeding on probing and vi) showed greater probing depths. The longitudinal evaluation of the papillae adjacent to the implant crown showed an improved proximal soft tissue fill at the follow-up examination. The VAS scoring of the patients' satisfaction with the appearance of their single implant-supported restorations revealed a median value of 96% with a range from 70 to 100%. Hence, observed differences in clinical crown height and soft tissue topography between implant-supported single-tooth replacements and the contralateral natural tooth may in most patients be of minor importance for the appreciation of the esthetic outcome of implant therapy.

Impact of endodontic conditions on marginal bone loss

This study was undertaken to examine the extent to which the marginal alveolar bone may be influenced by the condition of the dental pulp. A total of 115 pairs of contralateral teeth were observed in 87 patients (25 to 45 years old) in which the test tooth, but not the control tooth, was either endodontically treated or not treated but with a periapical radiolucency. The distance from the cemento-enamel junction to the marginal bone level was measured using intraoral radiographs. The condition of the endodontic filling, the periapical status, and the presence of root canal post were also assessed. With clinical parameters similar between teeth in the two groups in terms of visible plaque, bleeding on probing, probing depth, and attachment level, the results showed a somewhat (mean value 0.1 mm; SD 0.7) larger reduction of the alveolar bone support in test than control teeth. This difference was not statistically significant on a patient level. Hence, this study failed to demonstrate a correlation between a reduced marginal bone support and endodontic status.

Treatment of periodontal disease in older adults

The literature does not indicate that older adults differ from younger individuals in their response to periodontal treatment. However, in older adults, it is more common to find compromised general conditions that may negatively affect the patient's ability to maintain an adequate standard of self-performed plaque control. Although this can be compensated for partly by a carefully designed program for supportive therapy, the prevention and/or elimination of clinical signs of periodontal inflammation may not always be a reachable goal of periodontal therapy in older adults, particularly in those who are frail and functionally dependent. For many patients, a more realistic goal may be the control of disease progression in order to preserve a functional and comfortable dentition throughout life and hence, the decision making process regarding therapeutic levels for the individual patient must include factors such as the amount of remaining periodontal support, the risk for disease progression, demands for oral health and life expectancy.

Prevalence of furcation involvements in patients referred for periodontal treatment

The aim of this study was to evaluate the prevalence of furcation-involved molars in a patient sample referred for periodontal treatment. A total of 222 patients aged, 14-73 years (mean age 45 years), and with signs of destructive periodontal disease in at least 2 quadrants of the dentition were included in the study. The clinical examination involved assessments of oral hygiene status, gingival conditions, probing pocket depth and presence/degree of furcation involvement. In addition, a full mouth intraoral radiographic examination was performed. The results revealed that 4% of the patients presented with all 12 molars, while 3% had lost all molars. 52% of the individuals had at least 8 molars; 95% of subjects < 30 years of age and 19% in the age 60+ years. In patients aged > or = 40 years, every 2nd molar showed advanced periodontal destruction in the furcation area. The prevalence of furcation involved molars was higher in the maxilla than in the mandible. From the age of 30 years, about 50% of the 1st and 2nd molars in the maxilla showed at least 1 furcation site with deep involvement, while in the mandible a similar prevalence was observed first after the age of 40 years. The highest frequency of furcation involvement was found at the distal site of the maxillary 1st molar (53%), and the mesial aspects of the maxillary 2nd molar showed the lowest frequency (20%). Furcation sites with a probeable trunk region were observed at a frequency of 17-22% at the various tooth sites. It was concluded that tooth morphology may be an important factor that accounts for the variability in prevalence of molar furcation involvement.

Recession of the soft tissue margin at oral implants. A 2-year longitudinal prospective study

The aim of this study was to longitudinally evaluate alterations in the position of the periimplant soft tissue margin, occurring during a 2-year period after insertion of fixed prostheses. 41 patients, subjected to treatment with partial or full-arch implant supported fixed prostheses based on a total of 163 standard Brånemark oral implants, were included in the study. A baseline examination was performed at time of insertion of the prosthetic construction and involved assessments of plaque, mucositis, probing depth, bleeding on probing marginal soft tissue level, width of masticatory mucosa and marginal soft tissue mobility. All patients were re-examined after 6 months, and after 1 and 2 years, respectively. A regression analysis was performed to evaluate if alterations, occurring in the position of the periimplant soft tissue margin during the 2 years, could be predicted by various variables recorded at time of the installation of the fixed prosthesis. The descriptive analysis showed a slight decrease in mean probing depth (0.2 mm) and width of masticatory mucosa (0.3 mm) during the follow-up period. Apical displacement of the soft tissue margin mainly took place during the first 6 months of observation. Lingual sites in the mandible showed the most pronounced soft tissue recession, decrease of probing depth, and decrease of width of masticatory mucosa. The statistical analysis revealed that lack of masticatory mucosa and mobility of the periimplant soft tissue at time of bridge installation were poor predictors of soft tissue recession occurring during the 2 years of follow-up, but indicated in greater amount of recession in women than men, in the mandible than in the maxilla, at lingual than at facial sites and with increased initial probing depth. It was suggested that the recession of the periimplant soft tissue margin mainly may be the result of a remodelling of the soft tissue in order to establish "appropriate biological dimensions" of the periimplant soft tissue barrier, i.e., the required dimension of epithelial-connective tissue attachment in relation to the faciolingual thickness of the supracrestal soft tissue.

Increased gingival dimensions. A significant factor for successful outcome of root coverage procedures? A 2-year prospective clinical study

The aim of this study was to evaluate whether an increased thickness of the gingiva through the use of a free connective tissue graft, in conjunction with a coronally advanced flap procedure, may positively influence the treatment outcome with respect to (i) root coverage and (ii) long-term stability of the position of the soft tissue margin following treatment of recession type defects. 67 consecutive patients having a total of 103 buccally located recession type defects of at least 3 mm were included in the study. After an initial phase of prophylaxis including instructions in a tooth brushing technique giving minimal apically directed forces to the gingival margin, the recession sites were surgically covered with a coronally advanced flap alone (control sites), or coronally advanced flap combined with a free connective tissue graft taken from the palate (test sites). Clinical examinations, including assessments of oral hygiene, gingival conditions, recession depth, gingival height, probing pocket depth and probing attachment loss, were performed before and 6, 12 and 24 months after surgical treatment. The mean initial recession depth for both treatment groups was about 4.0 mm (SD 1.0) with a gingival height apical to the recession of 1.0 mm (0.5). At the re-examination performed 6 months after surgical treatment, the mean recession depth had decreased to 0.2 mm in both the test and control groups. Complete root coverage was observed at 72% of the test sites and 74% of the control teeth. At teeth treated with the combined surgical procedure, the mean gain in probing attachment amounted to 3.7 mm and the mean gingival height had increased to 3.5 mm (0.6). The corresponding figures for control teeth were 3.6 mm and 1.5 mm (0.5), respectively. At the 24-month follow-up examination, the mean root coverage amounted to 98.9% (test) and 97.1% (control). 88% of the teeth in the test group showed complete root coverage compared to 80% for teeth in the control group. It was concluded that the 2 surgical procedures resulted in similar degree of root coverage and that changes of tooth brushing habits may be of greater importance than increased gingival thickness for long-term maintenance of the surgically established position of the soft tissue margin.

Long-term follow-up of cross-arch fixed partial dentures in patients with advanced periodontal destruction: evaluation of occlusion and subjective function

The study aimed to investigate occlusal factors in fixed partial dentures (FPDs) still in service for more than 10 years, and to assess the patients' opinions regarding oral function with these constructions. Thirty-four patients with 43 FPDs were examined clinically concerning occlusion and by means of a questionnaire on functional aspects. The most common occlusal contact pattern was group function (51% on both sides, 7% on one side) while canine protected occlusion was recorded in 16% on both sides, 7% on one side. Balanced occlusion (19%) was mainly found when the FPD occluded against a complete denture and when there were few abutments and a small amount of abutment supporting tissue. The number and intensity of the occlusal contacts were assessed by means of thin occlusal sheets (50 microns). On average, one occlusal contact was observed on each dental unit with antagonist. The average number of sheets that could be introduced between the antagonists when the patient bit hard in the intercuspal position was two without significant differences between different areas (anterior/posterior) or type of dental unit (abutment, pontics, cantilever section). In the cantilever sections there were looser contacts (more interocclusal sheets) more distally. The great majority of patients were satisfied with the function of their FPDs (mastication, phonetics, aesthetics, comfort, and hygiene). Subjective function was not significantly influenced by FPD design, occlusal factors or number of FPD units. The only significant difference observed was that patients with a small amount of supporting tissues said they had more difficulties with hard foods than the others had. Although a stable occlusion was found in all FPDs, none of the other occlusal parameters examined were related to the long-term results.

Mucogingival considerations in orthodontic treatment

Alterations in the mucogingival complex will occur during orthodontic tooth movement, but these are independent of the apico-coronal width (height) of the gingiva. The integrity of the periodontium can be maintained during orthodontic therapy also in areas that have only a minimal zone of gingiva. In terms of changes in the position of the soft tissue margin and in gingival dimensions, the important factors to consider are the direction of the tooth movement and the bucco-lingual thickness of the gingiva. Lingual tooth movement will result in an increased bucco-lingual thickness of the tissue at the facial aspect of the tooth which results in coronal migration of the soft tissue margin (decreased clinical crown height). Facial tooth movement, on the other hand, will result in a reduced bucco-lingual tissue thickness and thereby a reduced height of the free gingival portion and an increased clinical crown height. The risk for development of recession type defects in conjunction with orthodontic tooth movement is present only if the tooth has been moved out of the alveolar bone housing, ie, when an alveolar bone dehiscence has been created.

Immunohistological characteristics of periodontal lesions associated with Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans infections

In this study, various phenotypes of infiltrating cells in the periodontium adjacent to pockets harboring Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans were evaluated. Furthermore, the pattern of class II antigen expression in the periodontal tissues was determined. Eight lesions were associated with the presence of P. gingivalis and 12 with A. actinomycetemcomitans. Predominant cells in the inflammatory infiltrate were T- and B-cells. In most biopsies T-cells dominated over B-cells. The proportion of P. gingivalis, but not of A. actinomycetemcomitans, was positively correlated to the total number of infiltrating cells in the tissue. A. actinomycetemcomitans sites demonstrated somewhat lower proportions of CD3+, CD4+ and CD19+ cells than P. gingivalis sites. However, the tendency of decreasing CD4+/CD8+ ratio with increasing number of A. actinomycetemcomitans indicates a local imbalance in immunoregulation. The frequency of class II antigen expression of both mononuclear and epithelial cells, a sign of immunological activation, was generally high.

Long-term follow-up of cross-arch fixed partial dentures in patients with advanced periodontal destruction. Evaluation of the supporting tissues

The aim of the study was to evaluate the periodontal conditions in patients treated more than 10 years ago for advanced periodontal disease and rehabilitated with cross-arch fixed partial dentures (FPDs). Of 50 randomly selected patients, 34 subjects carrying 43 FPDs agreed to participate in a clinical and radiographic follow-up examination. The FPDs were divided into three groups on the basis of prosthesis design (end abutments, unilateral cantilever, and bilateral cantilevers) and amount of supporting tissues at the time of bridge installation. Seventy per cent of the FPDs were found to be unchanged, whereas the rest had been modified due to various complications leading to extraction of one or more of the abutment teeth. Six FPDs (14%) had been partially replaced by FPDs anchored to osseointegrated dental implants. A total of 21 (8%) of the original 274 abutment teeth had been extracted. Longitudinal changes in the amount of periodontal support were minimal over the average of 15 years of follow-up. FPD design or initial amount of supporting tissues was found not to have significant influence on longitudinal changes in periodontal conditions. It was concluded that combined periodontal and prosthodontic treatment of patients with advanced loss of periodontal support may provide a high rate of long-term successful outcome, provided proper adequate periodontal and prosthetic treatment and maintenance care are given.

Acute-phase proteins and immunoglobulin G against Porphyromonas gingivalis in peri-implant crevicular fluid: a comparison with gingival crevicular fluid

This investigation had 2 aims: 1) to determine the levels of acute-phase proteins and immunoglobulin G (IgG) against Porphyromonas gingivalis in peri-implant crevicular fluid (PICF) and their association with the clinical condition of the peri-implant mucosa; and 2) to compare the inflammatory and immunological responses at implants and teeth as reflected by the gingival crevicular fluid (GCF) and PICF levels of acute-phase proteins and immunoglobulins. Thirty-one partially edentulous subjects were recruited for this study. PICF was sampled from 1 healthy and 1 inflamed site from each patient; GCF was sampled from an additional 21 healthy and 27 inflamed tooth sites of the same patients. GCF and PICF were collected with paper strips (for 30 s) and analysed using enzyme-linked immunosorbent assays for alpha 2-macroglobulin, alpha 1-antitrypsin, transferrin, lactoferrin and IgG against P. gingivalis. This investigation demonstrated that the absolute amounts of the acute-phase proteins and IgG against P. gingivalis are higher in GCF and PICF from inflamed than healthy sites. No significant differences were observed between PICF and GCF components at either healthy or inflamed sites, suggesting that inflammatory and immune events are similar in the peri-implant mucosa and gingiva in humans and that PICF and GCF production is governed by similar mechanisms.

Observer performance in locating the bifurcation in mandibular molars on periapical radiographs

The ability to identify radiographically the bifurcation in mandibular molars and the influence of morphological factors on the observers' decisions were investigated in 10 dry mandibles. Standardized periapical radiographs were obtained with and without lead markers in the bifurcation. Then 23 observers marked the bifurcation on tracing paper placed on the radiographs. The distance between the 'true' bifurcation (the lead indicators) and the observers' markings was assessed. On average, it was identified at a point 0.26 mm (s.d. 0.5) apical to its 'true' location on the first molar, and 0.65 mm (s.d. 1.15) coronal on the second molar. Interobserver variation for first and second molars was 0.5 mm and 1.06 mm respectively. Corresponding intraobserver variation was 0.47 mm and 1.14 mm. Of the four morphological characteristics analysed, the mesiodistal width of the bifurcation was found to have the strongest influence on the accuracy. It was concluded that the wide discrepancy in the ability of the observers to locate the bifurcation could be largely attributed to intraindividual variation.

Radiographic detectability of bone loss in the bifurcation of mandibular molars: an experimental study

The aim of this study was to evaluate observer performance in the diagnosis of bone loss in the bifurcation of mandibular molars on conventional radiographs. Standardized radiographs were obtained of the first and second molars in 10 dry hemimandibles at baseline and after preparation of bony defects corresponding to degree I and degree II buccal furcation involvements. The radiographs were randomly presented to 12 observers who were asked to determine the presence or absence of bone loss. Receiver operating characteristic (ROC) curve analysis was used for evaluation. The mean AZ-value of all observers was 81% for the first molar and 80% for the second. As the degree of furcation involvement increased, the mean AZ-value of the observers also improved from 68% (furcation involvement degree I) to 86% (degree II). Multiple regression analysis revealed that lesion depth was the factor which most strongly influenced the observers' diagnostic performance.

The influence of the masticatory mucosa on the peri-implant soft tissue condition

The aim of this study was to evaluate the soft tissue conditions at osseo-integrated oral implants in relation to the width of masticatory mucosa. Thirty-nine patients who had received a full-arch fixed bridge reconstruction > or = 10 years ago or a partial reconstruction > or = 5 years ago on a total of 171 implants ad modum Brånemark were included in the study. The examinations involved assessments of plaque, gingivitis, bleeding on probing, probing depth, width of masticatory mucosa and marginal tissue mobility. Simple correlation analysis as well as multiple regression analysis were performed to evaluate relationships between recorded parameters. The results showed that 24% of the sites were lacking masticatory mucosa, and an additional 13% of the implants had a width of less than 2 mm. Mobility of the facial marginal soft tissue, i.e., lack of an attached portion of masticatory mucosa, was observed at 61% of all implants. No major differences in the clinical parameters examined were found between sites with and without an "adequate" width of masticatory mucosa. Multiple regression analyses revealed that neither the width of masticatory mucosa nor the mobility of the border tissue had a significant influence on (i) the standard of plaque control or (ii) the health condition of the peri-implant mucosa, as determined by bleeding on probing. Hence, the study failed to support the concept that the lack of an attached portion of masticatory mucosa may jeopardize the maintenance of soft tissue health around dental implants.

The prevalence and distribution of gingival recession in subjects with a high standard of oral hygiene

The aim of this study was to evaluate the prevalence and the development/progression of attachment loss and gingival recession at buccal tooth surfaces in a population sample with a high standard of oral hygiene. An additional aim was to study the relationship between attachment loss and gingival recession. The subject sample examined comprised 225 regular dental care attendants at 12 community dental clinics in Sweden. All subjects were subjected to a baseline examination in 1977-78 and were re-examined after 5 years and 12 years. The clinical examinations involved assessment of plaque, gingivitis, probing depth, probing attachment loss and gingival recession. A full-mouth set of intraoral radiographs was obtained at each examination and used for determination of the height of periodontal bone support. The results of the cross-sectional and longitudinal analyses performed showed that in subjects with a high standard of oral hygiene (i) buccal gingival recession was a frequent finding, (ii) the proportion of subjects with recession increased with age, (iii) the prevalence as well as the incidence of recessions within the dentition showed different patterns depending on age, (iv) sites with recession showed susceptibility for additional apical displacement of the gingival margin and (v) loss of approximal periodontal support was associated with gingival recession at the buccal surface.

Periodontal conditions of adult regular dental care attendants. A 12-year longitudinal study

The purpose of the present study was to examine longitudinal alterations in the periodontal conditions of regular dental care attendants. 225 randomly selected patients (age 18-65 years) at 12 community dental clinics in the county of Värmland, Sweden, were subjected to a baseline clinical and radiographic examination in 1978 and to a re-examination in 1990. During the study period, all participants received preventive and therapeutic measures according to decisions made by the dentist on duty in the clinics. The examinations involved assessments of number of remaining teeth, plaque, gingivitis, probing pocket depth, loss of probing attachment and periodontal bone height. The results showed that during the 12 years of monitoring, an average of 0.4 teeth were lost. The % of tooth sites with gingivitis was lower in 1990 (4%) than in 1978 (15%), but no major changes were found for the mean probing pocket depth. The mean probing attachment loss during the 12 years amounted to 0.5 mm. The tooth site analysis revealed that buccal sites had experienced more loss of attachment than lingual and approximal surfaces. Whereas no differences were observed between age groups with respect to longitudinal loss of attachment at lingual and approximal tooth sites, the youngest age group demonstrated more pronounced loss at buccal surfaces than older subjects. The radiographic assessments of the alveolar bone height revealed a mean longitudinal loss amounting to 0.2-0.4 mm in the various age groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Extent and severity of periodontal destruction based on partial clinical assessments

The aim of the present study was (i) to identify the 10 approximal tooth sites that provide Extent and Severity estimates of clinical attachment loss which are maximally coherent to the full mouth scores, and (ii) to evaluate the applicability of such a partial recording system. Data from two subject samples, comprising 192 subjects aged 30-64 yr (sample A) and 175 subjects aged 35-80 yr (sample B), were involved in the development and the evaluation of the system, respectively. Approximal probing attachment loss (PAL) measurements were available from all subjects. A PAL value of > 1 mm was required for a tooth site in order to qualify for the Extent and Severity computations. A full mouth bivariate Extent and Severity Index (FESI) was firstly calculated for every subject in sample A. Multiple regression models applied on data derived from the same sample identified the 10 approximal tooth sites which provided the best correlation to the full-mouth scores (correlation coefficients between partial and full mouth scorings of Extent and Severity 0.85 and 0.88, respectively). All tooth types were found to be represented in this set of sites and the ratio of mesial/distal sites was 6/4. The applicability of a partial recording system (PESI) based on these sites was evaluated in sample B. Fully comparable estimates between PESI and FESI values were obtained, but the degree of correlation varied at different ages. Further adjustments by means of regression models failed to increase the validity and reliability of the PESI.(ABSTRACT TRUNCATED AT 250 WORDS)

Periodontal tissue response to orthodontic movement of teeth with infrabony pockets

The aim of this study was to evaluate the effect of orthodontic tooth movement on the level of the connective tissue attachment in sites with infrabony pockets. The experiment was carried out in four beagle dogs. The second and fourth premolars were extracted. After healing, angular bony defects were prepared at the mesial aspect of the third premolars. The exposed root surface was scaled and planed, and a notch was prepared at the bottom of the defect. Plaque-collecting cotton floss ligatures were placed around the neck of the teeth and maintained in situ for 3 weeks, followed by an additional 2 months of plaque accumulation before the orthodontic tooth movement was initiated. In each dog, one premolar was moved away from the angular bony defect and one premolar into and through the angular bony defect. The maxillary third premolars served as control teeth and were not subjected to orthodontic tooth movement. After orthodontic treatment (5 to 6 months), the teeth were stabilized for a period of 2 months before biopsy sampling. Clinical, radiographic, and histologic evaluations revealed that it was possible to establish and maintain an infrabony pocket with a subcrestal, plaque-induced inflammatory lesion during the entire course of the study. While the control teeth had maintained their attachment levels, all but one of the orthodontically moved teeth showed additional loss of attachment.(ABSTRACT TRUNCATED AT 250 WORDS)

Orthodontic tooth movement into edentulous areas with reduced bone height. An experimental study in the dog

The present study was performed in order to test the hypothesis that the height of supporting bone and connective tissue attachment will be maintained around teeth bodily moved into areas of reduced bone height. During a pre-experimental period, areas with markedly reduced bone height were produced in the mandible of 4 beagle dogs through extraction of the 4th premolars and subsequent surgical reduction of the bone height in the extracted sites to a level corresponding to half the root length of the 3rd premolar. Following healing, one of the third premolars was bodily moved in a distal direction into the area of reduced bone height, while the contralateral premolar served as a non-moved control. After 6 months of active tooth movement, the teeth were retained in their new position for a further 2 months before biopsies of test and control tooth sites were sampled. Radiographic evaluation showed that a bodily movement had been achieved with no or only minimal vertical displacement of the teeth. The histological analysis revealed that none of the teeth, orthodontically moved or not, had experienced loss of connective tissue attachment. Although a greater distance between the cemento-enamel junction and the bone crest was found on the pressure side of the orthodontically moved test teeth in comparison to the contralateral, non-moved control teeth, the bone level at all test teeth was more coronally positioned than the original, reduced bone level in the area into which the test teeth had been moved. Hence, these findings indicate that a tooth with a normal height of periodontal support can be orthodontically moved into an area of markedly reduced bone height with maintained height of the supporting apparatus.

An analysis of the subgingival microflora in randomly selected subjects

The aim of this study was to describe the presence of some microbial species in the subgingival microflora of a randomly selected subject sample. A further objective was to analyze the association between some microbiological characteristics and the periodontal conditions of the subjects. A total of 171 individuals aged 30-65 years were included. A pooled subgingival plaque sample was obtained from the mesial aspect of the 6 Ramfjord teeth by the use of the paper-point method. The samples were processed and analyzed according to standardized procedures. The periodontal condition of the subjects was examined clinically and included assessment of plaque, gingivitis, probing pocket depth and probing attachment level. The results showed that 81% of the subjects were positive for Campylobacter rectus, 80% for Fusobacterium nucleatum, 77% for Streptococcus sanguis, 72% for Streptococcus mitis, 66% for Eikenella corrodens, 58% for Prevotella intermedia, 32% for Capnocytophaga, 27% for Selenomonas, 25% for Actinobacillus actinomycetemcomitans, 14% for Porphyromonas gingivalis and 13% for Streptococcus mutans. Small differences in the periodontal conditions were observed between subjects harboring P. gingivalis, A. actinomytecomitans or > 5% P. intermedia and the rest of the sample. Similarly small differences in the clinical parameters were revealed when the subjects were grouped according to proportions of disease-associated and health-associated species in their subgingival samples.

Subgingival irrigation systems for the control of oral infections

The use of subgingival irrigation systems for the control of oral infections is an attractive possibility. The main advantage would seem to be that it would provide a means of delivering therapeutic agents to sites otherwise inaccessible to the effects of mouthrinses. Much research has therefore concentrated on the methods of delivery and the agents so delivered. The effects of various trials on individuals with good and poor oral hygiene and using a variety of different agents is reviewed.

Evaluation of a radiographic partial recording system assessing the extent and severity of periodontal destruction

The purpose of the present study was to evaluate the validity and reliability of a partial radiographic bivariate index system (PESI-2). The principles of the index were applied to data from a random sample of 192 industrial employees aged 30-65 yr. Estimates of Extent and Severity of radiographic bone loss provided by the PESI-2, as well as adjusted estimates by means of simple regression models, were compared to values obtained by a full mouth radiographic examination. It was shown that the values provided by the PESI-2 were of rather high validity and reliability. The use of the adjusting models resulted in increased validity of the severity estimates and enhanced reliability of both components of the bivariate. The results verified the applicability of the PESI-2 in epidemiologic research of destructive periodontal disease.

Extent and Severity Index based on assessments of radiographic bone loss

The purpose of the present study was to develop a partial recording system based on the principles of the Extent and Severity Index, aiming at describing the degree of radiographic alveolar bone loss on a population level. The data analyzed were derived from a subject sample comprising 531 individuals aged 25-75 yr. In these subjects alveolar bone level (ABL) was radiographically assessed at all approximal tooth surfaces. An ABL value of greater than 2 mm was required for a tooth site to be included in the computation of a full mouth bivariate Extent and Severity Index (FESI). A partial recording index (PESI-2) based on 18 ad hoc selected tooth sites depicted in one periapical and one vertical bitewing radiograph was evaluated in comparison with the FESI as well as with partial recording indices based on the 9 and 18 tooth sites which displayed the highest correlation with full mouth scores (PESI-9 and PESI-18, respectively). It was shown that all three partial recording systems generated values reasonably close to the full-mouth scores. However, the fitness of all partial indices varied with age. The potential of the partial indices to predict full-mouth scores could be further enhanced via simple regression models. Such an evaluation should, ideally, be carried out in an independent subject sample.

The angular bony defect as indicator of further alveolar bone loss

The aim of the present retrospective study was to evaluate alterations of the alveolar bone level over a 10-year period at tooth sites with "angular" and "even" patterns of bone loss, in subjects who were not exposed to systematic periodontal therapy. A further objective was to evaluate whether the presence of an angular defect can serve as a predictor of additional bone loss. 201 subjects in ages 25-70 years were examined radiographically on 2 occasions 10 years apart. 194 were dentate on the 2nd examination. The radiographic bone height at the mesial and distal aspect of all teeth was assessed by measuring the distance between the cemento-enamel junction and the bone crest. The morphologic pattern of alveolar bone loss at baseline was assessed for each tooth site. Angular defects were classified as degree 1, 2 and 3, according to increasing defect depth. The change in periodontal bone height over the 10-year period was calculated for each site. The results demonstrated an increased frequency of tooth loss among teeth showing presence of an angular bony defect at baseline; whereas 13% of the teeth with an even pattern of bone loss were lost between the 2 examinations, this proportion was 22%, 46% and 68% for teeth with an angular defect of degree 1, degree 2 and degree 3, respectively. Longitudinal bone loss of greater than or equal to 2 mm occurred more often among sites showing an angular defect when compared to sites with an even alveolar bone morphology.(ABSTRACT TRUNCATED AT 250 WORDS)

Periodontal treatment needs assessed by the use of clinical and radiographic criteria

The aim of the present study was to use a decision making model in order to assess the periodontal treatment needs of a random sample of employees in a large Swedish industrial corporation. The model used provided data on critical bone loss limits for different tooth types and ages, beyond which treatment must be initiated, in order to fulfill the goal of maintaining all teeth in a functional state throughout life. A sample comprising 192 subjects belonging to four age strata (31-35 yr, 41-45 yr, 51-55 yr, and 61-65 yr) was involved. From each subject, a full mouth series of intra-oral radiographs were available. The radiographic bone height was assessed at the mesial and distal aspect of all teeth by measuring the distance between the cementoenamel junction and the bone crest. The clinical examination included assessments of plaque, gingivitis, probing pocket depth, and probing attachment level. The results revealed that (i) only 3.1% of all approximal tooth sites exhibited radiographic bone loss exceeding the critical limit, (ii) all individuals and 70% of the approximal tooth sites were in need periodontal treatment when presence of gingival inflammation (bleeding on probing) was employed as the single criterion for therapeutic intervention, (iii) the proportion of individuals and tooth sites requiring treatment amounted to 98% and 27%. respectively, when a probing pocket depth of at least 4 mm was included as an additional criterion, and 54% and 4.1%, respectively, if a probing depth threshold of 6mm was used, while (iv) the use of bleeding on probing in combination with radiographic bone loss beyond the critical limits disclosed a need of treatment in 40% of the subjects and 2.5% of the approximal tooth sites.

A model for decision making regarding periodontal treatment needs

The aim of this study was to present a tentative model for decision making regarding periodontal treatment needs, based on the amount of remaining periodontal bone support. In the model presented, a maintained alveolar bone height of one third of the root length at the age of 75 years was regarded to be a reasonable goal. The data analyzed were derived from a patient sample of 194 dentate individuals aged 25-70 years from whom 2 full mouth series of intraoral radiographs, approximately 10 years apart, were available. For teeth present at both examinations, the radiographs were evaluated with respect to alveolar bone levels at the mesial and distal aspect of the teeth, i.e., the distance between the cemento-enamel junction and the most coronal level of the bone support. Longitudinal alveolar bone level change was determined for each tooth site and the alteration in alveolar bone height per 5-year interval between 25 and 75 years of age was described. Based on the calculated mean bone loss data, a rate factor was determined for each tooth site and used in the final description of the alveolar bone level for each particular tooth site at ages 30, 35, 40, ..., and 70 years, depicting the amount of bone loss beyond which therapeutic intervention has to be made in order to meet the defined goal of the tentative model. The relevance of the model and its applicability are discussed.

The significance of the width and thickness of the gingiva in orthodontic treatment

The results of the studies reviewed have shown that, while the apico-coronal width of the gingiva is unlikely to affect the development of a recession defect, the thickness of the marginal soft tissue may be essential for the prevention of soft tissue recession in conjunction with orthodontic therapy. The clinical implication of these findings is that tooth movement--particularly tooth movement in facial/lingual direction--should be preceded by careful examination of the dimensions of the tissues covering the "pressure side" of the teeth to be moved. As long as the tooth can be moved within the envelope of the alveolar process, the risk for harmful side-effects in the marginal soft tissue is minimal, irrespective of dimensions or quality of the soft tissue. If, however, the tooth movement is expected to result in the establishment of an alveolar bone dehiscence, the volume (thickness) of the covering soft tissue must be considered as a factor which may influence the development of soft tissue recessions during, as well as after, the phase of active orthodontic therapy. A thin gingiva may serve as a locus minorus resistentiae to developing soft tissue defects in the presence of bacterial plaque. This means that in tooth regions with a thin covering soft tissue, the patient must be encouraged to carry out effective but at the same time non-traumatic plaque control measures. If surgical intervention is considered in order to reduce the risk for development of soft tissue recession following orthodontic therapy, this should aim at increasing the thickness of the covering tissue (e.g. by the use of connective tissue grafts) and not the apico-coronal width of gingiva.

A 10-year retrospective study of periodontal disease progression. Clinical characteristics of subjects with pronounced and minimal disease development

The present study reports on some characteristics of 2 groups of subjects, chosen from a sample of 191 dentate individuals who had been exposed to full-mouth intraoral radiographic examinations in 1975 and 1985. The 1st group, which comprised 14 subjects, had experienced pronounced loss of periodontal bone support during a 10-year period (mean longitudinal bone loss of 4.13 mm (S.D. 1.4]. The 2nd group of 14 subjects had suffered no or minimal periodontal disease progression (mean longitudinal bone gain of 0.35 mm (S.D. 0.7]. A clinical examination was performed in conjunction with the radiographic examination in 1985 and included assessment of plaque, gingivitis, bleeding on probing from the base of the pocket, probing depth and probing attachment loss. Information regarding the oral hygiene habits of the subjects as well as the amount of dental and periodontal therapy received between 1975 and 1985 was obtained through a questionnaire. The results revealed that the 14 subjects who had experienced pronounced progression of periodontal disease had more plaque and gingivitis, deeper pockets and more attachment loss than the 14 subjects with minimal periodontal disease progression. Over the 10-year period, subjects in the "high rate" group had lost a mean of 6.8 teeth (S.D. 5.0) as compared to 4.1 teeth (S.D. 4.4) in the "low rate" group. The radiographic assessments of alveolar bone loss were strongly correlated with the assessments of probing attachment loss (r = 0.80, p = 0.0001). In 92% of the tooth sites examined, the difference between the radiographic and the clinical assessment was within 2 mm.(ABSTRACT TRUNCATED AT 250 WORDS)

Radiographic and clinical assessments of destructive periodontal disease

191 subjects, aged 35-80 years, were examined for periodontal disease using radiographic and clinical means. At all approximal tooth surfaces, assessments were made of (i) the distance on radiographs between the cementoenamel junction and the most coronal level of the alveolar bone, and (ii) probing attachment loss. The results revealed that (i) a strong correlation existed between the radiographic and the clinical assessments (r = 0.80, p = 0.0001), (ii) the difference between the 2 types of assessments was within 2 mm in 92% of the tooth sites examined, (iii) the degree of agreement between the 2 methods was similar, irrespective of tooth type and tooth surface, but (iv) the agreement was poor at sites with severe periodontal tissue breakdown.

A 10-year retrospective study of periodontal disease progression

The purpose of this study was to record the rate of periodontal disease progression over a 10-year period with respect to individual subject, age and tooth type. 283 subjects, who had undergone a full-mouth radiographic examination in 1974-76 and at that time were 25-70 years old, were randomly selected from a larger patient sample for a new radiographic examination in 1985-86. 201 subjects (71%) agreed to participate. For each respondent, tooth loss over the 10-year period was calculated. The radiographic bone height at the mesial and distal aspect of all teeth was assessed by measuring the distance between the cemento-enamel junction and the bone crest. Difference in periodontal bone height between the 2 examinations was calculated for each tooth site. The results revealed that the mean number of teeth lost over the 10-year period was 3.8 (SD 4.6). Tooth mortality, expressed as a % of the no. of teeth present at the initial examination, increased with age and varied between 2.9%-28.5%. In all age groups, molars had the highest and canines the lowest rate of tooth mortality. The frequency of subjects with loss of greater than 10 teeth was highest for the initially 45-year old individuals (20%). 7 individuals (3%) had become edentulous. The mean annual reduction of alveolar bone height varied between 0.07-0.14 mm in the age groups 25-65 years. The initially 70-year old subjects showed a statistically significant higher annual rate of bone loss (0.28 mm).(ABSTRACT TRUNCATED AT 250 WORDS)

Development of gingiva following surgical exposure of a facially positioned unerupted incisor

A case with a facially positioned, unerupted maxillary incisor is presented as an illustration of the potential of the periodontal tissues to establish a zone of gingiva following surgical intervention. Despite the fact that the tooth had an erupting position entirely within the area of the alveolar mucosa, a zone of keratinized gingiva developed following surgical exposure of the crown of the tooth. This healing potential should be considered when selecting the treatment for facially positioned, unerupted teeth.

Mouthrinses in "experimental gingivitis" studies

The experimental gingivitis study design is a frequently used clinical model for the evaluation of the effects of antimicrobial agents on developing plaque and gingivitis. In individuals who at the start of the experiment have clean teeth and healthy gingivae and who use a mouthrinse containing the test agent as the only tooth cleaning measure during a period of 14-21 days, the anti-plaque and anti-gingivitis potential of the agent can be properly evaluated. The present paper describes different designs of experimental gingivitis studies for the evaluation of chemotherapeutic agents used to control supragingival plaque formation. Findings reported in the literature with respect to the effects obtained by various antimicrobial compounds are also reported.

Periodontal status in relation to age and tooth type. A cross-sectional radiographic study

The purpose of the present study was to assess by radiographic means the pattern of destructive periodontal disease within the dentition of individuals of different ages. Full-mouth series of intra-oral radiographs from 531 dentate individuals aged 25-75 years were examined with respect to number and type of remaining teeth, location of the alveolar bone in relation to the cemento-enamel junction and presence of angular bony defects. The assessments of alveolar bone levels and angular bony defects were performed at the approximal surfaces of all teeth present. The results showed that although most individuals had experienced a reduction in alveolar bone height with age, only a small number of subjects had developed advanced breakdown of the periodontium. Hence, pronounced bone loss was observed in only 11% of the subjects and was non-existent in ages below 35 years. 23% of the individuals accounted for 3/4 of the total number of sites with bone level values (bone loss) of greater than or equal to 6 mm. Out of the total number of tooth sites examined, 28% showed no bone loss, while 13% demonstrated pronounced periodontal tissue breakdown. Angular bony defects were found at 8% of all teeth examined and were most frequent at the maxillary first premolars. Teeth in the incisor regions consistently showed the highest frequency of advanced alveolar bone loss and the lowest frequency of normal tissue support, while corresponding figures for teeth in the molar regions were found to be the opposite. However, molars were the most frequently missing teeth.

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.

Periodic subgingival antimicrobial irrigation of periodontal pockets. II. Microbiological and radiographical observations

The purpose of this study was to evaluate the microbiological effects of repeated subgingival irrigation of deep periodontal pockets as a single measure of treatment as well as combined with mechanical debridement, and to study the concomitant radiographical changes of the alveolar bone. 2-3 interproximal sites per jaw quadrant in 10 patients showing a probing depth of greater than or equal to 6 mm and bleeding on pocket probing were selected for the study. The pockets in the various quadrants were randomly assigned to professionally performed subgingival irrigation with 0.2% chlorhexidine gluconate, 3% hydrogen peroxide or saline or to non-irrigation. During a first phase of treatment, the pockets were periodically irrigated (every 2nd-3rd day during weeks 1-2 and 5-6) and no subgingival mechanical debridement was performed. During a second phase, subgingival scaling and root planning were carried out with adjunctive subgingival irrigation of the pockets. During the entire trial, the patients' plaque control was carefully supervised. Sampling of the subgingival microflora was performed before and after the first and second treatment phases and 3 months after the termination of the active treatment. Dark-field assessment and cultivation of the bacterial samples were performed. The radiographical examination was carried out at the start of each treatment phase and 3 months after the termination of phase II and the radiographs were analysed by the use of a subtraction technique. The results demonstrated that periodic subgingival antimicrobial irrigation per se had only limited and transient effects on the subgingival microflora.(ABSTRACT TRUNCATED AT 250 WORDS)

Periodic subgingival antimicrobial irrigation of periodontal pockets (I). Clinical observations

The present investigation was undertaken to study the clinical effect of professionally performed periodic subgingival irrigation per se and as an adjunct to scaling and root planing. 10 patients suffering from moderate-severe periodontal disease participated in the study. Following an initial 3-month period of supervised supragingival plaque control, a total of 102 periodontal sites with probing pocket depth greater than or equal to 6 mm and "bleeding on probing" were selected and subjected to a Baseline examination comprising assessments of oral hygiene and gingival conditions, probing depths and probing attachment levels. The pockets in the various jaw quadrants were randomly assigned to one of the following treatment groups: (1) periodic subgingival irrigation with hydrogen peroxide, (2) periodic subgingival irrigation with chlorhexidine, (3) periodic subgingival irrigation with saline and (4) no subgingival treatment. During the first part of the study (baseline-32 weeks), no mechanical debridement of the subgingival area was performed. The irrigation treatment was carried out by the operator 3 times per week during weeks 1 + 2 and 5 + 6 of the trial. In the 2nd part of the trial (32-52 weeks), the sites were subjected to scaling and root planing combined with professional irrigation during weeks 32-38. The previously non-irrigated control sites were not subjected to adjunctive irrigation when mechanically debrided. During the entire study, the patients were recalled for professional tooth cleaning once every 4 weeks. Re-examinations were carried out at 4, 6, 32, 40 and 52 weeks. The results revealed that repeated professional irrigation of unscaled periodontal pockets with chlorhexidine or hydrogen peroxide resulted in a temporarily reduced frequency of bleeding sites, but not in any clinically significant changes in probing assessments. A similar improvement of bleeding scores was observed in the saline-irrigated control group. Scaling and root planing, in combination with an optimal supragingival plaque control, resulted in a marked resolution of the clinical symptoms of periodontal disease. Adjunctive irrigation with chlorhexidine or hydrogen peroxide did not improve the healing result above and beyond that obtained after mechanical debridement alone or in combination with saline irrigation. Hence, the study failed to demonstrate that professionally performed periodic subgingival irrigation with chlorhexidine or hydrogen peroxide, used alone or in combination with thorough mechanical debridement, has a significant therapeutic effect.

Lack of association between width of attached gingiva and development of soft tissue recession. A 5-year longitudinal study

The purpose of this study was to longitudinally monitor changes in the position of the soft tissue margin at 26 buccal sites surgically deprived of all gingival tissue. A baseline examination carried out 6 months after treatment revealed that the sites to be monitored were lacking or had only a minimal zone (less than 1 mm) of regenerated attached gingiva. 12 control sites with an "adequate" width of attached gingiva (greater than 1 mm) were also examined. Assessments of oral hygiene and gingival conditions, probing pocket depths, probing attachment levels, position of the soft tissue margin, and gingival width were carried out at baseline and after 5 years. The results revealed that in the test sites, a slight increase of the width of the gingiva occurred during the observation period. 7 out of the 26 areas showed a coronal regrowth of the soft tissue margin, while 2 sites showed a further apical displacement of the soft tissue margin. In the control areas, 3 sites developed recession accompanied by a reduction in the width of the gingiva. Hence, it appears that in patients maintaining a proper plaque control, the lack of an "adequate" zone of attached gingiva does not result in an increased incidence of soft tissue recessions.