A randomized multi-centre study on the effectiveness of non-surgical periodontal therapy in general practice.

AIM: To evaluate the effectiveness of two non-surgical treatment protocols for periodontitis patients in general dental practice. MATERIALS AND METHODS: Ninety-five dental hygienists (59 dental clinics) were randomly assigned to one of two treatment protocols: (i) establishment of adequate self-performed oral hygiene prior to a single session of ultrasonic instrumentation (guided periodontal infection control [GPIC]) or (ii) conventional non-surgical therapy (CNST) including patient education and scaling and root planing integrated in multiple sessions. Residual pockets at 3 months were retreated in both groups. The primary outcome was pocket closure (probing pocket depth ≤ 4 mm) at 6 months. Multilevel models were utilized. RESULTS: Based on data from 615 patients, no significant differences with regard to clinical outcomes were observed between treatment protocols. Treatment-related costs (i.e., chair time, number of sessions) were significantly lower for GPIC than CNST. Smoking and age significantly affected treatment outcomes. CONCLUSIONS: No significant differences between the two approaches were observed in regard to clinical outcomes. GPIC was more time-effective. Patient education should include information on the detrimental effects of smoking. CLINICALTRIALS: gov (NCT02168621).

Patient-reported experiences and outcomes following two different approaches for non-surgical periodontal treatment: a randomized field study.

CONTEXT: The current report is part of a prospective, multi-center, two-arm, quasi-randomized field study focusing on the effectiveness in general praxis of evidence-based procedures in the non-surgical treatment of patients with periodontitis. OBJECTIVE: The specific aims were to (i) evaluate patient-reported experience and outcome measures of treatment following a guided approach to periodontal infection control (GPIC) compared to conventional non-surgical therapy (CNST) and to (ii) identify potential predictors of subjective treatment outcomes and patient's adherence to self-performed infection control, i.e. adequate oral hygiene. METHODS: The study sample consisted of 494 patients treated per protocol with questionnaire- and clinical data at baseline and 6-months. The GPIC approach (test) comprised patient education for adequate oral hygiene prior to a single session of full-mouth ultra-sonic instrumentation, while the CNST approach (control) comprised education and instrumentation (scaling and root planing) integrated at required number of consecutive appointments. Clinical examinations and treatment were performed by Dental Hygienists, i.e. not blinded. Data were processed with bivariate statistics for comparison between treatment groups and with multiple regression models to identify potential predictors of subjective and clinical outcomes. The primary clinical outcome was gingival bleeding scores. RESULTS: No substantial differences were found between the two treatment approaches regarding patient-reported experiences or outcomes of therapy. Patients' experiences of definitely being involved in therapy decisions was a significant predictor for a desirable subjective and clinical outcome in terms of; (i) that oral health was considered as much improved after therapy compared to how it was before, (ii) that the treatment definitively had been worth the cost and efforts, and (iii) adherence to self-performed periodontal infection control. In addition, to be a current smoker counteracted patients' satisfaction with oral health outcome, while gingival bleeding scores at baseline predicted clinical outcome in terms of bleeding scores at 6-months. CONCLUSIONS: The results suggest that there are no differences with regard to patient-reported experiences and outcomes of therapy following a GPIC approach to periodontal infection control versus CNST. Patients' experiences of being involved in therapy decisions seem to be an important factor for satisfaction with care and for adherence to self-performed periodontal infection control. Registered at: ClinicalTrials.gov (NCT02168621).

Peri-implant tissue healing at implants with different designs and placement protocols: An experimental study in dogs.

OBJECTIVES: To compare the peri-implant tissue response to subcrestal or crestal placement of implants with or without "platform-switched" implant/abutment connections. MATERIAL AND METHODS: On each side of the mandible in six Labrador dogs, two "platform-switched" (PS) implants and two implants with matching implant/abutment diameters (PM) were placed in a crestal or a 1.5 mm subcrestal position. Sulcus formers/abutments were connected, baseline radiographs obtained and the distance between the abutment-fixture junction (A/F) and the marginal bone level (B) was determined. Five months later, radiographic and clinical examinations were repeated and biopsies were obtained and processed for histological analysis. RESULTS: The radiographic analysis showed that marginal bone level changes occurred during the first observation period (13 weeks). PS-implants showed minor marginal bone level alterations during the full observation period (20 weeks), regardless of placement depth. For PM-implants, placement had a significant impact on bone level changes; crestal placement resulted in a mean bone loss of 0.4 mm and subcrestal placement in a 1.5 mm bone loss. The histometric measurements resulted in a distance A/F-B of 0.6 and 0.0 mm for PS implants, placed in a crestal or subcrestal position, respectively. The corresponding distance at PM-implants was 1.5 mm irrespective of placement protocol. The peri-implant mucosa was thicker at subcrestally placed implants as compared to a crestal placement. CONCLUSIONS: Bone remodeling occurred within the early healing phase. During the full 20 weeks of observation, PS-implants demonstrated significantly less crestal bone loss compared to PM-implants.

Placement of two-part implants in sites with different buccal and lingual bone heights.

BACKGROUND: Recipient sites for implants often exhibit a vertical discrepancy between the buccal and lingual bone crest. The potential to preserve the lingual bone when placing the implant within the dimension determined by the buccal bone in such sites remains to be evaluated. METHODS: Five dogs were included in this study. The premolars were extracted on one side of the mandible, and a buccal defect was prepared by the resection of a 2-mm-high portion of the buccal bone wall. Three months later, two test (surface modification on the shoulder part of the implant) and two control implants were placed within the area of the buccal bone defect. Following placement, the implant margin at the buccal side coincided with the buccal bone crest, whereas the implant margin at the lingual side was in a subcrestal position. Regular abutments with a turned surface were connected to the control implants, whereas experimental abutments with a modified surface were connected to the test implants. A plaque-control program was initiated. Four months later, biopsies were obtained and prepared for histologic analysis. RESULTS: The marginal bone level was located at a more coronal position at the lingual aspect than at the buccal aspect of the test implants, whereas the buccal and lingual bone levels were similar at control implants. CONCLUSION: It is suggested that different marginal bone levels are obtainable at the lingual and buccal aspects when two-part implants with suitable surface characteristics are placed in sites with different buccal and lingual bone heights.

Subcrestal placement of two-part implants.

OBJECTIVE: The aim of the present experiment was to study the healing around two-part implants that were placed in a subcrestal position. MATERIAL AND METHODS: Five mongrel dogs, about 2 years old, were included. The mandibular premolars and the first, second and third maxillary premolars were extracted. Three months later two test and two control implants (OsseoSpeed, 3.5 mm x 8 mm) were placed in one side of the mandible. The implants were placed in such a way that the implant margin was located 2 mm apical to the bone crest. In the test implants, the surface modification extended to the implant margin and, thus, included the shoulder part of the implant. Regular abutments with a turned surface (Zebra) were connected to the control implants, while experimental abutments with a modified surface (TiOblast) were connected to the test implants. A plaque control program that included cleaning of implants and teeth every second day was initiated. Four months later the dogs were euthanized and biopsies were obtained and prepared for histological analysis. RESULTS: The marginal bone level at the test implants was identified in a more coronal position than that at the control implants. In 40% of the test implants, the bone-to-implant contact extended coronal of the abutment/fixture (A/F) border, i.e. in contact with the abutment part of the implant. The connective tissue portion of the peri-implant mucosa that was facing the test abutments contained a higher density of collagen and a smaller proportion of fibroblasts than that at the control sites. CONCLUSION: It is suggested that osseointegration may occur coronal to the A/F interface of two-part implants. Such a result, however, appears to depend on the surface characteristics of the implant components.

The mucosal barrier at implant abutments of different materials.

OBJECTIVE: The aim of the present study was to analyze the soft tissue barrier formed to implant abutments made of different materials. MATERIAL AND METHODS: Six Labrador dogs, about 1 year old, were used. All mandibular premolars and the first, second and third maxillary premolars were extracted. Three months later four implants (OsseoSpeed, 4.5 x 9 mm, Astra Tech Dental, Mölndal, Sweden) were placed in the edentulous premolar region on one side of the mandible and healing abutments were connected. One month later, the healing abutments were disconnected and four new abutments were placed in a randomized order. Two of the abutments were made of titanium (Ti), while the remaining abutments were made of ZrO(2) or AuPt-alloy. A 5-months plaque control program was initiated. Three months after implant surgery, the implant installation procedure and the subsequent abutment shift were repeated in the contra-lateral mandibular region. Two months later, the dogs were euthanized and biopsies containing the implant and the surrounding soft and hard peri-implant tissues were collected and prepared for histological analysis. RESULTS: It was demonstrated that the soft tissue dimensions at Ti- and ZrO(2) abutments remained stable between 2 and 5 months of healing. At Au/Pt-alloy abutment sites, however, an apical shift of the barrier epithelium and the marginal bone occurred between 2 and 5 months of healing. In addition, the 80-mum-wide connective tissue zone lateral to the Au/Pt-alloy abutments contained lower amounts of collagen and fibroblasts and larger fractions of leukocytes than the corresponding connective tissue zone of abutments made of Ti and ZrO(2). CONCLUSION: It is suggested that the soft tissue healing to abutments made of titanium and ZrO(2) is different to that at abutments made of AuPt-alloy.

Healing at implants placed in an alveolar ridge with a sloped configuration: an experimental study in dogs.

PURPOSE: To study healing around implants placed in an alveolar ridge with a sloped lingual-buccal configuration. MATERIALS AND METHODS: Six Labrador dogs were used. Buccal bone defects were prepared in the mandible after extraction of premolars. Three months later, two test implants with a sloped marginal design and two control implants were placed in the chronic defect area with a sloped lingual-buccal configuration of each premolar region. The test implants were placed in such a way that the buccal margin of the implant coincided with the buccal bone crest. The lingual margin of the control implants was placed to a similar depth as the lingual margin of the test implants. Abutments were connected to the implants in the right mandibular premolar region and flaps were sutured around the neck of the abutments. In the left side of the mandible, cover screws were placed and the flaps were sutured to cover the implants. Biopsies were obtained 4 months later and prepared for histological examination. RESULTS: It was demonstrated that healing around implants placed in an alveolar ridge with a sloped lingual-buccal configuration resulted in the preservation of a vertical discrepancy between the lingual and buccal marginal bone levels around implants with either a regular cylindrical outline or a modified marginal portion that matched the slope of the alveolar ridge. CONCLUSION: As the marginal buccal portion of the control implants with a regular design had no bone support, it is suggested that implants with a modified marginal portion may be considered in recipient sites with a sloped lingual-buccal configuration.

Morphogenesis of the peri-implant mucosa: an experimental study in dogs.

PURPOSE: The objective of the present experiment was to study the morphogenesis of the mucosal attachment to implants made of c.p. titanium. MATERIAL AND METHODS: All mandibular premolars were extracted in 20 Labrador dogs. After a healing period of 3 months, four implants (ITI Dental Implant System) were placed in the right and left sides of the mandible. A non-submerged implant installation technique was used and the mucosal tissues were secured to the conical marginal portion of the implants with interrupted sutures. The sutures were removed after 2 weeks and a plaque control program including daily cleaning of the remaining teeth and the implants was initiated. The animals were sacrificed and biopsies were obtained at various intervals to provide healing periods extending from Day 0 (2 h) to 12 weeks. The mandibles were removed and placed in the fixative. The implant sites were dissected using a diamond saw and processed for histological analysis. RESULTS: Large numbers of neutrophils infiltrated and degraded the coagulum that occupied the compartment between the mucosa and the implant during the initial phase of healing. At 2 weeks after surgery, fibroblasts were the dominating cell population in the connective tissue interface but at 4 weeks the density of fibroblasts had decreased. Furthermore, the first signs of epithelial proliferation were observed in specimens representing 1-2 weeks of healing and a mature barrier epithelium occurred after 6-8 weeks of healing. The collagen fibers of the mucosa were organized after 4-6 weeks of healing. CONCLUSION: It is suggested that the soft-tissue attachment to implants placed using a non-submerged installation procedure is properly established after several weeks following surgery.