The number of peer-reviewed journals covering the various aspects of dentistry is huge, certainly too big for busy dental practitioners to keep up with. As a special service to our readers, World Dental Reporter brings a selection of literature abstracts, chosen by our editorial board as being particularly worthy of attention.

Periodontics

De novo bone formation following the sinus lift procedure.
The primary objective of this study was to use histomorphometric techniques to evaluate the concept that the new bone formed in the maxillary sinus lift procedure emanates from the endosteum of the sinus floor. In addition, the effect of residual crest vertical dimension on graft outcome is described. The assessment of osteoclast numbers as an indirect measure of a connection between the crest and the graft compartment is reported.
After grafting the maxillary sinus with irradiated allogenic bone, thirty seven intact vertical bone cores of 2.7 mm in diameter were trephined at right angles to the crest. Quantitative measures were derived from histomorphometric analysis of new bone and residual graft particles at contiguous zones along the long axis of the cores. Mean and median data were analysed for associations with distance from the sinus floor, dimensions of the residual crest, and other descriptive variables. A parallel series of TRAP-stained sections were evaluated for osteoclast counts.
New bone formation ranged from 24.3% to 30.2%. A statistically significant gradient of graft particle area combined with this uniform distribution of new bone resulted in a false impression of less consolidation with distance from the floor. There was no significant relationship between distance from the sinus floor or dimension of residual crest and graft result. Osteoclast counts revealed a statistically significant difference (p< 0.001) between the residual crest and the graft compartment with increased counts in the graft. Histologically, the new bone-forming process resembled a combination of de novo appositional and intramembraneous ossification. The findings suggest a passive role for graft material and implicate the ingrowth of vascular and perivascular tissues as the most logical source of osteogenic capacity.
Price AM, Nunn M, Oppenheim FG, Van Dyke TE. J Periodontol 2011 Jan 14.

Systemic antimicrobials adjunctive to a repeated mechanical and antiseptic therapy for aggressive periodontitis: a 6-month randomised controlled trial.
The additional benefit of systemic antimicrobials versus placebos was compared with  a repeated mechanical instrumentation combined with a comprehensive local chemical plaque control for the periodontal treatment of generalised aggressive periodontitis (GAP). This was a 6-month randomised, double-blinded, placebo-controlled clinical trial. All GAP patients received “full-mouth disinfection” followed by staged scaling and root planing without (placebo, n=17) or with (test, n=18) systemic antimicrobials (amoxicillin 500mg, AMX + metronidazole 250mg MET, t.i.d. for 10 days). Clinical parameters were measured at baseline, 3 and 6 months post-therapy. Statistically significant differences between groups at baseline were anaylsed by Mann-Whitney test, whereas comparisons over time were examined by GLM for repeated measurements. Both groups demonstrated similar improvements in most parameters over time. The test group presented greater mean PD reduction and CAL gain at sites with initially moderate PD at 6 months (p<0.03). No differences were seen between groups regarding mean reduction and mean gain respectively for PD and CAL initially ≥7mm. The test group had a higher percentage of sites which improved by ≥2mm and ended up with PD ≤4mm or a lower percentage of sites which worsened by ≥2mm, and remained with PD >4mm at 3 months (p<0.01). No differences were noticed between groups for those parameters at 6 months. Thus AMX + MET bring additional clinical effects to the repeated mechanical and antiseptic treatment of GAP, at very short time (3 months); the effect was not necessarily sustained over time
(6 months).
Varela VM, Heller D, Silva-Senem MX, Torres MC, Colombo AP, Feres-Filho EJ.J Periodontol 2011 Jan 14.

Adjunctive effect of a water-cooled Nd:YAG laser in the treatment of chronic periodontitis.
This study tested whether the use of a water-cooled Nd:YAG laser adjunctive to supra- and subgingival debridement (SRP) with hand and ultrasonic instruments results in greater clinical improvement than SRP alone. Another objective was to investigate the reduction in the number of microorganisms as a result of the treaments. The study was an examiner-blind, randomised and controlled clinical trial using a split-mouth design. Nineteen subjects with moderate-to-severe generalised periodontitis were selected. Immediately following SRP in two randomly chosen contra-lateral quadrants, all pockets greater than 4 mm were additionally treated with the Nd:YAG laser (1064 nm, 6 W, 400 mJ). Clinical assessments (Plaque index, bleeding on pocket probing, probing pocket depth) were performed pre-treatment and at 3 months post-treatment. In each quadrant, one site was sampled for microbiological evaluation at pre-treatment, immediately post-instrumentation and 3 months post-treatment.
At the 3-month visit, the clinical parameters had significantly improved for both regimens. No significant differences between treatment modalities were observed for any of the clinical parameters at any time. Immediately following instrumentation, the total colony forming units for both groups were significantly reduced as compared with pre-instrumentation. No significant differences between treatment modalities were observed.
Three months after SRP, no additional advantage was achieved with the additional use of the Nd:YAG laser. Microbiological findings reflected these clinical results.
Slot DE et al. J Clin Periodontol 2011 Jan 11.

Association between periodontal infection and obesity: results of the Health 2000 Survey.
This study investigated the role of periodontal infection in obesity in an adult population. The study was based on a subpopulation of the Health 2000 Survey that included dentate and non-diabetic subjects, aged 30-49 years (n=2784). Obesity was measured using the body mass index (BMI), body fat percentage (BF%) and waist circumference (WC). The extent of periodontal infection was measured using the number of teeth with deepened (4 mm deep or deeper) periodontal pockets and was categorised into four categories (0, 1-3, 4-6, 7 or more).
The number of teeth with deepened periodontal pockets was found to be associated with BMI in an exposure-response manner among the total study population. The association was found among men and women, and also among never-smokers. The number of teeth with deepened periodontal pockets was also associated with BF% and WC among never-smokers.
Periodontal infection measured by means of the number of teeth with deepened periodontal pockets appears to be associated with obesity. However, no inferences about causality can be made and further studies are needed to clarify the possible role of periodontal infection in obesity.
Saxlin T, Ylöstalo P, Suominen-Taipale L, Männistö S, Knuuttila M. J Clin Periodontol. 2010 Dec 27.

Endodontics

Revitalisation of tooth with necrotic pulp and open apex by using platelet-rich plasma: a case report.
A growing body of evidence is demonstrating the possibility of regeneration of tissues within the pulp space and continued root development in teeth with necrotic pulp and open apexes. The purpose of this case report is to add a regenerative endodontic case to the existing literature regarding the use of platelet-rich plasma (PRP).
An 11-year-old boy whose maxillary second premolar tooth had been accidently extracted and immediately replanted developed pulpal necrosis and symptomatic apical periodontitis. After preparing an access cavity, its necrotic pulp was removed. The canal was irrigated with 5.25% NaOCl solution and dried with paper points. A triple antibiotic mixed with distilled water was packed in the canal and left for 22 days. Twenty millilitres of whole blood was drawn from the patient’s forearm for preparation of PRP. After removal of the antibiotic mixture, the PRP was injected into the canal space up to the cementoenamel junction level. Three millimetres of grey mineral trioxide aggregate was placed directly over the PRP clot. Three days later, the tooth was double-sealed with permanent filling materials.
Clinical examination 5 1/2 half months later revealed no sensitivity to percussion or palpation tests. Radiographic examination of this tooth showed resolution of the periapical lesion, further root development and continued apical closure. Sensitivity tests with cold and an electric pulp test elicited a positive response similar to those found in the first premolar tooth.
On the basis of short-term results of the present case, it appears that regeneration of vital tissues in a tooth with necrotic pulp and a periapical lesion is possible; PRP is potentially an ideal scaffold for this procedure
Torabinejad M, Turman M. J Endod. 2011 Feb;37(2):265-8.

Efficacy of sonic and ultrasonic activation for removal of calcium hydroxide from mesial canals of mandibular molars: a microtomographic study.
The purpose of this study was to use micro-computed tomography (micro-CT) scanning to evaluate the efficacy of sonic and passive ultrasonic irrigation (PUI) on calcium hydroxide (CaOH2) removal and to measure the volume and percentage of CaOH2 remaining in the root canal system.
The root canals of 46 extracted human mandibular molar teeth, prepared with rotary instruments, were randomly assigned to two experimental groups (n = 40); positive and negative controls (n = 6) were also included. In each experimental group, 20 teeth were assigned to each irrigation protocol: either sonic or passive ultrasonic irrigation. All experimental teeth and the positive controls were filled with CaOH2, whereas the negative control teeth did not receive CaOH2. All teeth were scanned using micro-CT to determine the dressing volume. After 7 days, the CaOH2 was removed in the experimental groups using rotary instrumentation only, and the teeth were again scanned using micro-CT to calculate volume and percentage of CaOH2 removed. Positive control teeth were not subjected to rotary instrumentation. Experimental samples were then irrigated using either sonic or passive ultrasonic and the volume of remaining CaOH2 was calculated using micro-CT.
Remnants of CaOH2 were found in all experimental groups. No CaOH2 was found in the negative controls, whereas a mean of 8.7 mm3 of CaOH2 was recorded in the positive controls. Rotary plus passive ultrasonic irrigation removed significantly more CaOH2 (85.7%) than rotary plus sonic irrigation (71.5%) (p < 0.001).
The combination of rotary instrumentation and passive ultrasonic activation for 3 periods of 20 seconds results in significantly lower amounts of CaOH2 remnants in the canal compared with sonic irrigation
Wiseman A, Cox TC, Paranjpe A, Flake NM, Cohenca N, Johnson JD. J Endod 2011 Feb;37(2):235-8.
A high-resolution Computed Tomographic study of changes in root canal isthmus area by instrumentation and root filling.
The aim of this study was to obtain a three-dimensional analysis of the isthmus area of the mesiobuccal root canal system in mandibular molars. High-resolution micro-computed tomography (μ-CT) scanning was used to measure the amount of debris and root filling material in the isthmus after instrumentation/irrigation and root filling.
Mandibular molars with two separated mesial root canals (10 teeth) were scanned by using the Skyscan 1172 μ-CT system (Skyscan, Aartselaar, Belgium) before and after instrumentation and after filling using the Thermafil root filling technique. An isthmus was defined as the ribbon-shaped or thin connecting structure between two root canals after instrumentation. The characteristics of the isthmuses were quantitatively monitored during the whole treatment and the images were segmented and quantified. The surface area of the isthmus, volume of debris after rotary instrumentation and volume of the filled space in the isthmus after obturation were evaluated.
Of the seven mesial roots, two had isthmus/anastomoses somewhere along their length in the apical 5 mm, and five had an isthmus that was continuous all the way from the coronal part to the apical part. The average percentage of isthmus surface area and isthmus volume after instrumentation was 21.4% and 9.4% of the whole root canal system, respectively. About 35.2% of the isthmus volume was filled with apparently hard tissue debris after instrumentation/irrigation. The average percentage of volume of filling material in the isthmus areas was significantly lower (57.5%) than in the main root canals (98.5%, p < 0.001).
A considerable amount of dentin debris is produced and packed into the isthmus area during rotary instrumentation of mesial canals of lower molars despite continuous irrigation during and after instrumentation. The debris may partly prevent penetration of the filling material and sealer into the isthmus area.
Endal U, Shen Y, Knut A, Gao Y, Haapasalo M. J Endod. 2011 Feb;37(2):223-7.

The response of subcutaneous connective tissue to newly developed calcium phosphate-based root canal sealers.
This study evaluated the histopathologic biocompatibility of two new calcium phosphate-based sealers (CPS-1 & CPS-2) with a commercially available calcium hydroxide-based sealer (Acroseal).
Polyethylene tubes were filled with freshly mixed sealers and implanted subcutaneously in the dorsal connective tissue of rats. Empty tubes were used as controls. Histopathological examinations were conducted at 7, 15, 30, 60 and 90 days after the implantation procedure. The presence of inflammation and predominant cell types were analysed statistically with Mann-Whitney U and Kruskal-Wallis non-parametric tests. Fibrous connective tissue thickness adjacent to each sample was recorded. Differences were tested for significance using anova and ‘Duncan’s’ multiple comparison test (P <0.05).
The CPS-1 sealer was associated with severe inflammation and remained an irritation throughout the 90-day implantation period; the tissue reaction pattern was stromal fibrosis. The control, CPS-2 and Acroseal sealers had similar patterns of irritation, which were more severe initially and diminished with time creating a thin fibrous capsule around the implant with a complete absence of inflammatory cells. There was no difference in tissue reaction between the control, CPS-1, CPS-2 and Acroseal groups in the first two observation periods (P > 0.05). However, there was a highly significant difference between the same groups at the last two observation periods (P < 0.01). There were also highly significant differences between the observation periods within all four groups at 7, 15, 30, 60 and 90 days (P < 0.01).
CPS-1 sealer was not biocompatible. CPS-2 sealer and Acroseal had a favourable biocompatibility level based on the histological findings.
Khashaba RM, Moussa MM, Chutkan NB, Borke JL.Int Endod J. 2011 Jan 28.

Orthodontology

Accidental ingestion of a fractured twin-block appliance.
Orthodontic appliances that become dislodged can cause problems in the airway or the gastrointestinal tract. Accidental ingestion of an appliance during a chair-side procedure or because of inadequate retention of the appliance can create a medical emergency with potentially serious complications, including death from aspiration of the foreign body. This article reports on the accidental ingestion of a fractured twin-block appliance. This paper discusses the ease with which removable appliances can become dislodged if retention is inadequate and describes some serious complications that can arise. Precautions the orthodontist can take to prevent such accidents are presented.
Rohida NS, Bhad WA. Am J Orthod Dentofacial Orthop. 2011 Jan;139(1):123-5.
Efficient usage of implant anchorage to treat overerupted maxillary first molar and mesially inclined mandibular molars.
This case report demonstrates the efficient use of implant anchorage in a patient with mesially inclined mandibular molars and an overerupted maxillary molar. A 14-year-old girl had an overerupted maxillary right first molar, possibly because of severely inclined mandibular right molars. Two-step use of miniplate anchorage in the right zygomatic process was proposed. As a first step, the overerupted maxillary first molar was intruded with elastic chains from the miniplate for 10 months. The maxillary right molars were then distalised using the miniplate to correct the Class II molar relationship. In the mandible, the first molar was extruded with intermaxillary elastics applied from the miniplate to the molar for 7 months after the uprighting of the mandibular right second molar. The results suggest that the use of 2-step implant anchorage is efficient for intrusion and distalisation of maxillary molars and extrusion and uprighting of mandibular inclined molars.
Ohura R, Kuroda S, Takahashi T, Tomita Y, Tanaka E. Am J Orthod Dentofacial Orthop. 2011 Jan;139(1):113-22.

Static frictional force and surface roughness of various bracket and wire combinations.
During sliding mechanics, frictional resistance is an important counterforce to orthodontic tooth movement, which must be controlled to allow application of light, continuous forces. This study investigated the static frictional resistance between three modern orthodontic brackets: ceramic with gold-palladium slot; ceramic and stainless steel; as well as 4 archwires (0.019 × 0.025-in):stainless steel; nickel-titanium; titanium-molybdenum alloy (TMA) and low-friction coloured TMA.
All tests were carried out in a dry state on a universal testing machine. Surface topography of bracket slots and archwires was studied by using a scanning electron microscope and quantified by using a surface roughness testing machine (profilometer).
In the scanning electron microscope measurements, the smoothest surface was the ceramic gold-palladium bracket and stainless steel wire. The profilometer quantified the surface roughness, which was also lowest for the ceramic gold-palladium bracket and stainless steel wire. The ceramic bracket with the gold-palladium slot showed the least frictional values in all combinations and could be a promising method of solving the problem of friction. Frictional values for coloured TMA were comparable with stainless steel wires and might be a good alternative during space closure in sliding mechanics.
Ceramic with gold-palladium slot bracket and coloured TMA archwire appears to be a good alternative to stainless steel in space closure with sliding mechanics.
Doshi UH, Bhad-Patil WA. Am J Orthod Dentofacial Orthop. 2011 Jan;139(1):74-9.

The monitoring of gingival crevicular fluid volume during orthodontic treatment: a longitudinal randomised split-mouth study.
This randomised split-mouth study aimed at evaluating whether an orthodontic appliance per se or orthodontic tooth movement can induce detectable changes in gingival crevicular fluid (GCF) volume, and thus whether GCF volume is a predictable biomarker for tissue remodelling incident to orthodontic tooth movement.
Sixteen healthy orthodontic patients (7 females and 9 males; mean age, 17.7 years; range, 13-27 years) with the need for extraction of the first upper premolars were enrolled. One randomly chosen maxillary canine was subjected to a distalising force by a 0.017 × 0.025 inch titanium-molybdenum alloy archwire and was considered as the test tooth (TT). The contralateral canine, which was not subjected to any force but was included in an orthodontic appliance, was used as a control (CT). GCF sampling was performed at both mesial and distal sites of the CTs and TTs at baseline, immediately before applying the orthodontic appliance, and after 1 hour, 24 hours, and 7, 14, and 21 days. A Periotron was used to measure the GCF volume.
A modest but significant increase in the GCF volume over time was seen in both the CTs (mesial sites) and the TTs (both mesial and distal sites) with no differences between the experimental teeth. Subclinical tissue inflammation consequent to the placement of the orthodontic appliance might be responsible for these GCF volume changes. Thus the GCF volume does not appear to be a reliable biomarker for tissue remodelling during orthodontic treatment.
Drummond S, Canavarro C, Perinetti G, Teles R, Capelli J Jr. Eur J Orthod. 2011 Jan 27.

Left/right asymmetries and open/closed differences of interdental forces in the mandible.
This investigation studied the variation in interdental forces between mandibular canines and lateral incisors of 19 volunteers (9 males and 10 females) aged 20-26 years for four configurations (mandible open/closed and left/right side). These forces were derived by pulling a stainless steel matrix strip between these teeth, six times per configuration, and registering the time variation with a high-resolution transducer. The repeated median smoothing algorithm was applied to find the maximum of each curve and a bootstrap method estimated the 95 per cent confidence intervals (CIs) for all 76 configurations.
Seventy-six percent of all paired force differences were found to be significant. Asymmetry phenomena were observed: the interdental forces differed significantly between the left and right sides and also between the open and closed position of the mandible. The interdental forces (4-21 N) showed a pattern modulated by volunteer-specific features: in 91 per cent of the configurations, the interdental forces were larger when the mouth was open. This observed pattern contributes to the instability observed in clinical practice, which necessitates permanent fixed lower retainer wear.
Jonke E, Manschiebel W, Freudenthaler JW, Bantleon HP, Prossinger H. Eur J Orthod. 2011 Jan 27.

Pediatric dentistry

Comparison of the remineralising potential of child formula dentifrices.
Although child formula fluoridated dentifrices can be used safely by young children, their remineralising capability remains questionable. This study evaluated the remineralising potential of child formula dentifrices on primary teeth via an in vitro single-section technique utilising a 7 days pH-cycling model.
Primary teeth were placed in demineralising solution for 96 h to produce artificial carious lesions 100 μm deep, cut longitudinally into 50 sections 100-150 μm thick and randomly assigned to five groups. Sections in Groups A to D were treated with dentifrices containing 500 ppm AmF, 500 ppm MFP, 500 ppm MFP and xylitol, or 500 ppm NaF, respectively. Group E sections were treated with a nonfluoridated dentifrice. Lesions were evaluated using polarised light microscopy and microradiography.
Group D (500 ppm NaF) sections exhibited a significant decrease in lesion depth, whereas those in Group E (nonF) showed a significant increase in depth (P < 0.05, paired t-test). Decrease in lesion progression was observed in Groups A, B and C.
The 500 ppm NaF dentifrice demonstrated remineralisation of carious lesions with a significant decrease in lesion depth, whereas dentifrices that contained AmF, MFP and MFP with xylitol decelerated the progression of demineralisation
Ekambaram M, Itthagarun A, King NM. Int J Paediatr Dent. 2010 Dec 2.

Clinicians’ preventive strategies for children and adolescents identified as at high risk of developing caries.
Clinicians handle diagnosis and treatment planning of caries in different ways, and the underlying factors leading to management of risk and choice of treatment strategies are poorly understood. The aim of this study was to investigate dentists’ and dental hygienists’ choices of preventive strategies for children and adolescents identified as at high risk of developing caries.
Using dental records, 432 out of a total of 3372 children aged 3-19 years in a Swedish county were identified to be at high risk of developing caries. Records were randomly selected for analysis in the study. Information of importance for the therapists’ choice of caries management strategies were obtained from the dental records.
The results showed that therapists considered tooth brushing instruction and fluoride treatment at the clinic to be of primary importance; this was the treatment given in 60% of the cases. Fluoride treatment at home and diet counselling were both chosen in half of the cases. Fissure sealant therapy was used in 21% of the cases, and 15% of the patients did not receive any preventive treatment at all. The results also showed that girls more often received fluoride treatment, tooth brushing instruction and oral hygiene information than boys.
In the majority of the children and adolescents, several preventive measures were provided. The more background factors included in the risk assessment, the more preventive measures were given. The differences between the treatments given to girls and the boys need to be investigated further.
Sarmadi R, Gahnberg L, Gabre P. Int J Paediatr Dent. 2010 Oct 21.

Tooth replantation as an alternative to dental implantology in adolescent patients.
A 16-years old female patient was referred to us in July 2006, 14 days after an accident, with traumatic intrusive luxation of the right upper central incisor. This caused a nasal floor and buccal cortical bone fracture. While the extraoral examination revealed traumatic lesions of the upper lip, the intraoral examination revealed intrusive luxation, pain and high mobility of the tooth, with bleeding of the adjacent oral tissue. The treatment protocol consisted of surgical buccal bone removal, tooth extraction, retrograde root-canal filling and tooth repositioning in occlusion with a resilient splinting. After 8 weeks the splinting was removed, and clinical and radiological examinations were taken at 3, 6, 9, 12, and 24 months after surgery. At the 24 months follow-up the root showed no radiographic signs of inflammation, resorption or ankylosis, and the function of the replanted tooth was fully maintained.
Tooth replantation can be considered an effective alternative to a dental implant whenever the latter is contraindicated in a young patient with incomplete skeletal development. The long-term success of such a procedure will probably require a multidisciplinary approach.
Ferrazzano GF, Orlando S, Ingenito A, Tia M, Sammartino G.Eur J Paediatr Dent. 2010 Dec;11(4):216-8.

Implantology

Evidence-based techniques to assess the performance of dental implants.
One of the most expensive treatments in dentistry is the use of dental implants to rehabilitate partially and fully edentulous patients. Due to the high costs of treatments and the ever increasing varieties of dental implants becoming available, clinicians are often faced with challenging situations to decide the best prostheses for their patients. As with other orthopaedic implants, dental implants need to be evaluated for their long-term efficacy in vivo before they can be considered clinically acceptable. In order to help clinicians make patient-oriented decisions, evidence-based techniques are becoming increasingly popular. These can be a very useful for translating research findings into clinical practice, thus narrowing the gap between research and clinical dentistry. This article discusses ways in which evidence-based techniques can help dental surgeons analyse and make informed clinical decisions about dental implant treatments.
Kashi A, Saha S.J Oral Implantol. 2010 Dec 27.

Implant treatment software planning and guided flapless surgery with immediate provisional prosthesis delivery in the fully edentulous maxilla. A retrospective analysis of 15 consecutively treated patients.
The clinical outcome of 15 consecutive patients (5 males and 10 females) with a mean age of 52 years (range 40 to 70), with edentulous arches and who were treated with implant-supported cross-arch bridges was evaluated. Two CT scans were performed, the first with the patient wearing the denture/radiographic guide and the radiographic index, and the second with the denture alone. The guided flapless surgical procedure was performed under local anaesthesia. Ninety implants were placed; the implant lengths ranged from 10 to 13 mm and the implant diameter was either 4.3 or 5 mm. All implants were immediately loaded with screw-retained provisional acrylic prostheses prepared in advance and delivered immediately after surgery. Clinical and radiographic follow-up visits were scheduled at 6, 12 and 18 months from surgery; implant survival rate, marginal bone levels, patient satisfaction and any complications were recorded.
After the follow-up period of 18 months, two patients each lost one implant. After 18 months, patients lost, on average, 1.6 mm of peri-implant marginal bone. A patient satisfaction questionnaire at 18 months revealed a very high level of satisfaction with the treatment. Although limited by the number of patients, this study showed that software- and CT-guided surgical planning for completely edentulous arches provides reliable results with high success rates.
Meloni SM et al. Eur J Oral Implantol. 2010 Autumn;3(3):245-51.
Outcome of dental implants in patients with and without a history of periodontitis: a 5-year pragmatic multicentre retrospective cohort study of 1727 patients.
This study evaluated the outcome of dental implants placed in patients with a history of periodontitis. Patients with no or mild history of periodontitis served as controls. A total of 1727 patients were divided into three groups according to their initial periodontal status: 630 patients were in the severe periodontitis (SP) group, 839 in the moderate periodontitis (MP) group, and 258 had no periodontitis (NP). Patients requiring periodontal treatment were treated prior to implantation. Various implant systems and procedures were used. In total, 3260 implants and 1707 implant-supported prostheses were placed in the SP group, 2813 implants and 1744 implant-supported prostheses in the MP group, and 647 implants and 424 implant-supported prostheses in the NP group. Outcome measures were prosthesis and implant survival.
Two-hundred and fifty patients were lost to follow-up 5 years after loading. Regarding prosthesis failures, 13 prostheses could not be placed or failed in 13 patients of the SP group (0.8%), 11 prostheses could not be placed or failed in 9 patients of the MP group (0.7%), and 3 prostheses failed in 3 patients of the NP group (0.9%). For implant failures, 130 (4.5%) implants failed in the SP group, 74 (3.1%) implants failed in the MP group, and 15 (3.0%) implants failed in the NP group. Most of the implant failures (90%) occurred before implant loading. There were no statistically significant differences between the three PSR groups (P > 0.05). A previous history of periodontal disease may thus not have a significant impact on implant failures up to 5 years after loading.
Gianserra R et al. Eur J Oral Implantol. 2010 Winter;3(4):307-14.