Risk factors for tooth loss and progression of periodontitis in patients undergoing periodontal maintenance therapy.

AIM: The aim of this study was to investigate patient- and tooth-level factors that may predict tooth loss and periodontitis progression in patients who have undergone at least 5 years of periodontal maintenance. MATERIALS AND METHODS: In this retrospective cohort study, 135 patients were examined after active periodontal therapy (APT) and periodontal maintenance for 5.09-8.65 years (mean 6.16 ± 0.74 years). Regression models were applied to identify risk factors associated with tooth loss and disease progression. RESULTS: Stage IV periodontitis (incidence rate ratio [IRR] = 4.61; 95% confidence interval, CI [2.97-7.18], p < .001), the presence of ≥5 sites with probing pocket depth (PPD) ≥5 mm at the end of APT (IRR = 2.04; 95% CI [1.32-3.20], p < .01), and residual PPD ≥7 mm at the end of APT (odds ratio [OR] = 3.01; 95% CI [1.14-7.94], p < .05) were risk factors for tooth loss. Residual PPDs of 5 mm (OR = 2.02; 95% CI [1.20-3.40], p < .01) and 6 mm (OR = 2.41; 95% CI [1.22-4.76], p < .05) at the end of APT were risk factors for disease progression. Above 3 mm, each 1 mm increase in maximum PPD/clinical attachment loss was associated with an increased risk of tooth loss and disease progression. CONCLUSIONS: Stage IV periodontitis is associated with an increased risk of tooth loss. Teeth with PPD ≥5 mm at the end of APT are at risk of periodontitis progression or tooth loss.

Metagenomic sequencing provides new insights into the subgingival bacteriome and aetiopathology of periodontitis.

"Open-ended" molecular techniques such as 16S rRNA sequencing have revealed that the oral bacteriome of subgingival plaque is more diverse than originally thought. 16S rRNA analysis has demonstrated that constituents of the overall bacterial community are qualitatively similar in health and disease, differing mainly in their relative proportions with respect to each other. Species in low abundance can also act as critical species, leading to the concept of global community dysbiosis which relates to shifts in community structure, rather than shifts in membership. Correlation analysis suggests that coordinated interactions in the community are essential for incipient dysbiosis and disease pathogenesis. The subgingival bacteriome also provides biomarkers that are useful for disease detection and management. Combined with clinical and biological parameters, these may assist clinicians in developing and implementing effective treatment strategies to restore microbial homeostasis and monitor disease. Identification of higher risk groups or poor responders to treatment using unique subgingival bacteriome signatures may also lead to early intervention.

Influence of maintenance care in periodontally susceptible and non-susceptible subjects following implant therapy.

OBJECTIVES: To compare the periodontal and peri-implant conditions of periodontally susceptible and periodontally healthy subjects under maintenance care for a period of at least 3 years. MATERIAL AND METHODS: Sixty periodontally susceptible patients (PSP) and 56 periodontally non-susceptible subjects (PHS) were treated with dental implants in the National Dental Centre Singapore (NDCS) and were maintained in a regular supportive periodontal care program for a mean of 6 years. Full mouth bleeding on probing (BoP), full mouth probing pocket depths (PPD), implant loss, and absence of crestal bone loss were recorded at the time of prosthesis delivery and following a mean follow-up of 6 years 2 months. RESULTS: Although there were significant differences in the BoP and the percentage of subjects with tooth probing pocket depth ≥5 mm between PSP and PHS at the time of implant prosthesis installation (T0 ), there were no significant differences between the two subject groups in the various parameters assessed at the follow-up visit (T1 ) (total number of teeth, percentage of subjects with implant probing pocket depth ≥5 mm, percentage of subjects with implant probing pocket depth ≥ 6 mm, absence of crestal bone loss, implant loss). CONCLUSION: Owing to a rigid regular SPT program, implants placed in PSP perform equally well when compared to implants installed in PHS over a mean period of 6-year follow-up.

Patient-reported outcome measures after routine periodontal and implant surgical procedures.

OBJECTIVES: To compare patient-reported outcome measures (PROMs) after different dental surgical procedures over a 1-week post-surgical period and in relation to duration of the surgery, and periosteal releasing incisions. To evaluate the prevalence of post-surgical complications. MATERIAL & METHODS: Four hundred and sixty-eight healthy dental patients requiring surgeries, such as crown lengthening (CL), open flap debridement (OFD) and implant installation (IMP) in the National Dental Centre, Singapore (2009-2011), were consecutively recruited. PROMs on bleeding, swelling, pain and bruising were obtained using Visual Analogue Scales (VAS) on days 0, 3, 5 and 7 post-operatively. RESULTS: On the day of surgery, the IMP procedure gave the lowest median VAS for all four PROM parameters. After a week, OFD still had a significantly higher VAS for swelling, pain and bruising. Patients who underwent procedures lasting more than 60 min. had higher VAS for all parameters except bleeding. After considering other important confounders, type of surgery procedure was no longer associated with the VAS score for any of the parameters. Time after surgery, male gender and shorter surgery duration reduced post-operative VAS for one or more of the parameters. Longer surgeon experience helps reduce VAS scores only for bleeding. Prevalence for tenderness to palpation was 11.6%, 8.9% and 12.2% for IMP, CL and OFD, respectively, 1-week post-operatively. Swelling and suppuration occurred rarely. CONCLUSIONS: The median VAS scores for all PROM parameters were generally low and reduced to near zero over a week following all three surgical procedures tested. Time after surgery and shorter surgery duration were associated with lower VAS scores in all the PROM parameters in this cohort of patients. Surgery type was not associated significantly with VAS after adjustment with other important confounders. Low prevalences of post-surgical complications were reported.

Anatomical, microbiological, and genetic considerations in treatment of Chinese periodontal patients.

The aim of the present narrative review was to highlight considerations when treating Chinese patients with periodontal diseases. These considerations can be broadly categorized into anatomical, microbiological, and genetic considerations. Anatomical considerations are tooth-related factors causing site-specific issues, and these include incisal palatal groove, root concavities, three-rooted permanent mandibular first molar, furcation entrance dimensions, cervical enamel projections, root trunk length, and molar root fusion. Aggregatibacter actinomycetemcomitans was found to be commensal in the oral flora of Chinese. The association between a single gene polymorphism and periodontal disease has not been unequivocally proven in Chinese populations. Despite these subtle differences compared to other ethnic populations, studies of Chinese participants from various geographic regions have demonstrated that periodontal disease in this particular ethnic group can be successfully treated.

Gingival profiles in a select Asian cohort: A pilot study.

AIM: The aim of the present study was to determine the facial gingival profiles of teeth with a healthy periodontium in an Asian population. METHODS: A total of 51 patients with a healthy periodontium were examined. Gingival thickness (GT) and gingival width (GW) were assessed at the maxillary and mandibular incisors to the first molars. GT was measured by transgingival probing (GT-TGP), and probe visibility through the marginal gingiva (GT-TRAN) was assessed. Results between groups (anterior and posterior, tooth types) were analyzed using one-way analysis of variance and t-test. RESULTS: The mean age was 30.3±11.4 years, with 27 females and 24 males. The mean GT-TGP was 1.39±52 mm, while the mean GW was 4.59±1.34 mm. Considerable intra-individual and interindividual variation in GT (TGP and TRAN) was noted. GT increased from the anterior to posterior, and was thinnest at the mandibular centrals to the first premolars and maxillary canines. GT-TGP and GW were influenced by tooth type, plaque, recession, and TRAN, but not age, sex, or ethnicity. GW were recorded lowest at the mandibular canines and all premolars. Thin gingiva was recorded at 63.8%-92% (GT-TGP<1.5 mm) and 75%-90% (GT-TRAN) of the anterior teeth. CONCLUSION: A high percentage of anterior teeth had thin marginal gingiva. There was poor agreement between GT-TGP and GT-TRAN.

Use of a collagen matrix for recession coverage in patients who received orthodontic therapy: a case series.

AIM: The aim of the present study was to determine the percentage of recession coverage achieved following surgery with a collagen matrix, and patient-reported outcome measures. METHODS: Five healthy adults who had completed orthodontic therapy with a gingival recession defect were recruited. Gingival recession coverage was performed using a two-layer, xenogeneic collagen matrix (Mucograft). During the first 2 weeks, the patients charted their perceptions on bleeding, swelling, pain, and bruising using a visual analog scale (VAS). Post-surgical complications were assessed clinically at 1 week, 2 weeks, and 1 month post-surgery. Recession dimensions were examined at 1, 3, 6, and 12 months. RESULTS: At 1 year, an average of 67% root coverage was achieved. The amount of recession coverage achieved was stable from 3 months. The results were maintained at 1 year. There were no post-surgical complications. All VAS parameters decreased to almost zero by day 14. From day 1, bleeding and pain decreased over time. However, there were peaks on days 2 and 3 for swelling and bruising, respectively, followed by a subsequent decrease. CONCLUSIONS: The use of Mucograft for recession coverage is effective and safe, with low morbidity and no post-surgical complications. Recession coverage achieved at 3 months remained stable in the 1-year follow-up period.

Effects of enamel matrix derivative and transforming growth factor-ß1 on connective tissue growth factor in human periodontal ligament fibroblasts.

BACKGROUND: Enamel matrix derivative (EMD) is suggested to stimulate transforming growth factor-ß (TGF-ß) production. Connective tissue growth factor (CTGF) is a downstream mediator of TGF-ß. This study explores the effects of EMD and TGF-ß1 on CTGF in periodontal ligament (PDL) fibroblasts and their interactions in PDL proliferation and development. METHODS: Human PDL cells were stimulated with EMD. To explore the effects of EMD and TGF-ß1 on CTGF expression, cells were treated with and without TGF-ß inhibitor, and CTGF protein levels were assayed by Western blot analysis. To study the role of CTGF in PDL development, cells were treated with CTGF inhibitor. DNA synthesis was analyzed by bromodeoxyuridine enzyme-linked immunosorbent assay. Reverse-transcription polymerase chain reaction was performed to examine messenger RNA expression of PDL osteoblastic differentiation markers: type I collagen, alkaline phosphatase, and osteocalcin. RESULTS: EMD induced a concentration-dependent increase of CTGF protein expression in PDL cells. EMD- and TGF-ß1-stimulated CTGF expression was significantly reduced in the presence of TGF-ß inhibitor. CTGF inhibition downregulated both EMD- and TGF-ß1-induced DNA synthesis. The effect of CTGF and EMD on osteoblastic mRNA expression in PDL cells is not obvious. CONCLUSIONS: EMD stimulates CTGF expression in human PDL cells, a process modulated by the TGF-ß pathway. CTGF can affect EMD- and TGF-ß1-induced PDL cell proliferation, but its effects on PDL with regard to osteoblastic differentiation remain inconclusive. The results provide novel insights into EMD-CTGF interaction in PDL cells.

Principles and implications of site preservation for alveolar ridge development.

The extraction of a tooth normally results in the loss of ridge height and width. Often, clinicians are faced with the management of edentulous sites that are less than optimal for prosthetic rehabilitation and implant restoration due to considerable alveolar ridge collapse after tooth removal. Site preservation using bone grafts or substitutes with and without a membrane maintain ridge dimensions and contours. However, some clinicians believe that such procedures are over-treatment. This paper reviews the concepts and indications for site preservation following tooth extraction for the purpose of facilitating implant placement and conventional prosthetic restoration.

Periodontic and orthodontic treatment in adults.

The purpose of this article is to provide an update of the interrelationship between periodontics and orthodontics in adults. Specific areas reviewed are the reaction of periodontal tissue to orthodontic forces, the influence of tooth movement on the periodontium, the effect of circumferential supracrestal fiberotomy in preventing orthodontic relapse, the effect of orthodontic treatment on the periodontium, microbiology associated with orthodontic bands, and mucogingival and esthetic considerations. In addition, the relationship between orthodontics and implants (eg, using dental implants for orthodontic anchorage) is discussed.