Journal Club- January 2023
Combined Periodontal and Orthodontic Treatment of Severely Compromised Teeth in Stage IV Periodontitis Patients: How Far Can We Go? Aimetti M, Garbo D, Vidotto C, Bongiovanni L, Citterio F, Mariani GM, Baima G, Romano F. Int J Periodontics Restorative Dent. 2022 Nov-Dec;42(6):731-738. doi: 10.11607/prd.6247. PMID: 36305924.
Periosteum Classification and Flap Advancement Techniques Around the Mental Foramen. Urban IA, Sommer C, Wang IC, Wang HL. Int J Periodontics Restorative Dent. 2022 Nov-Dec;42(6):753-759. doi: 10.11607/prd.5921. PMID: 36305927.
Wound healing dynamics, morbidity, and complications of palatal soft-tissue harvesting. Tavelli, L, Barootchi, S, Stefanini, M, Zucchelli, G, Giannobile, WV, Wang, H-L. Periodontol 2000. 2022; 00: 1- 30. doi: 10.1111/prd.12466
Accidental ingestion of a dental object during periodontal surgical procedure on IV sedated patient: case management. Dastouri, E, Heck, TY, Wang, HL. Clin Adv Periodontics. 2022; 00: 00- 00. doi:10.1002/cap.10225
Evaluation of biologic width re-establishment using CHU aesthetic gauges in crown lengthening cases- a clinical study. Rani et al. Journal of Oral Biology and Craniofacial Research 13 (2023) 138-145. doi: 10.1016/j.jobcr.2022.12.006
Comparison of the effectiveness of Gingival Unit Transfer and Free Gingival Graft in the management of localized Gingival recession – A systematic review. Chetana et al. Journal of Oral Biology and Craniofacial Research 13 (2023) 130-137. doi: 10.1016/j.jobcr.2022.11.007
The Effects of Injectable Platelet-Rich Fibrin on Implant Stability. Güvenç S, Durmuşlar MC, Ballı U. Int J Oral Maxillofac Implants. 2022 Nov-Dec;37(6):1145-1150. doi: 10.11607/jomi.9629. PMID: 36450019.
Survival of Dental Implants Placed Pre-Radiotherapy Versus Post-Radiotherapy in Native Bone: A Systematic Review. Atanásio Pitorro TE, de Araújo Reis NT, Paranhos LR, Ferreira Soares PB. Int J Oral Maxillofac Implants. 2022 Nov-Dec;37(6):1100-1109. doi: 10.11607/jomi.9756. PMID: 36450015.
Implant failure and associated risk factors of transcrestal sinus floor elevation: A retrospective study. Li N, Jiang Z, Pu R, Zhu D, Yang G. Clin Oral Implants Res. 2023 Jan;34(1):66-77. doi: 10.1111/clr.14020. Epub 2022 Nov 17. PMID: 36346662.
Influence of the abutment height on marginal bone level changes around two-piece dental implants: Meta-analysis and trial sequential analysis of randomized clinical trials. Muñoz M, Vilarrasa J, Ruíz-Magaz V, Albertini M, Nart J. Clin Oral Implants Res. 2022 Dec 8. doi: 10.1111/clr.14025. Epub ahead of print. PMID: 36482067.
Individual “alveolar phenotype” limits dimensions of lateral bone augmentation. Quirynen M, Lahoud P, Teughels W, Cortellini S, Dhondt R, Jacobs R, Temmerman A. J Clin Periodontol. 2022 Dec 27. Epub ahead of print. PMID: 36574768.
Retrospective cohort assessment of survival and complications of zygomatic implants in atrophic maxillae. Vrielinck L, Moreno-Rabie C, Coucke W, Jacobs R, Politis C. Clin Oral Implants Res. 2022 Dec 21. Epub ahead of print. PMID: 36541107.
American Academy of Periodontology Best evidence consensus statement on the use of biologics in clinical practice. Avila-Ortiz G, Ambruster J, Barootchi S, Chambrone L, Chen CY, Dixon DR, Geisinger ML, Giannobile WV, Goss K, Gunsolley JC, Heard RH, Kim DM, Mandelaris GA, Monje A, Nevins ML, Palaiologou-Gallis A, Rosen PS, Scheyer ET, Suarez-Lopez Del Amo F, Tavelli L, Velasquez D, Wang HL, Mealey BL. J Periodontol. 2022 Dec;93(12):1763-1770. doi: 10.1002/JPER.22-0361. Epub 2022 Oct 24. PMID: 36279407.
Clinical outcomes of retention of the buccal root section combined with immediate implant placement: a systematic review of longitudinal studies. Kotsakis GA, Nguyen TT, Siormpas K, Pikos MA, Pohl S, Tarnow D, Mitsias M; Root Membrane Group. Clin Implant Dent Relat Res. 2022 Nov 4. doi: 10.1111/cid.13150. Epub ahead of print. PMID: 36331494.
Treatment of periodontitis and C-reactive protein: A systematic review and meta-analysis of randomized clinical trials. Luthra, S., Orlandi, M., Hussain, S. B., Leira, Y., Botelho, J., Machado, V., Mendes, J. J., Marletta, D., Harden, S., & D’Aiuto, F. Journal of Clinical Periodontology, 50(1), 45– 60. 2023.
Risk factors for tooth loss and progression of periodontitis in patients undergoing periodontal maintenance therapy. Siow DSF, Goh EXJ, Ong MMA, Preshaw PM. J Clin Periodontol. 2023;50(1):61-70. doi:10.1111/jcpe.13721
Topic: Combined Perio/ orthodontic therapy
Title: Combined Periodontal and Orthodontic Treatment of Severely Compromised Teeth in Stage IV Periodontitis Patients: How Far Can We Go?
Source: Int J Periodontics Restorative Dent. 2022 Nov-Dec;42(6):731-738
Type: Retrospective study
Keywords: periodontitis, complications, diagnostic imaging, therapy, retrospective studies, tooth loss.
Purpose: to analyze radiographic and clinical effect of combined periodontal and orthodontic therapy.
Methods: records from patients who were treated for stage IV periodontitis and pathologic tooth migration (PTM) were obtained (January 1999 up to November 2017). Treatment procedures included orthodontic tooth movement (OTM), active periodontal therapy (APT), and supportive periodontal care (SPC).
Before the start of OTM, patients received APT. Sites that did not respond were planned for surgery to obtain PD≤4mm with no BOP. 3 to 6 months after APT, OTM began on patients with full mouth plaque score and bleeding <20%.
Patients were treated with a full fixed appliance and bonded brackets. Light force was utilized (10 to 15g per tooth). Reactivation was done every 8 to 10 weeks and professional prophylaxis was carried out every 2 months. Once treatment was finished, patients received a lingual bonded retainer. After completion of OTM, patients underwent FMX and placed on supportive therapy with individualized intervals.
Orthodontic treatment goals
Change molar and canine relationships to a Class I
To close anterior tooth spacing
Correct overbite and overjet
To reestablish stable occlusion
Results: The files of 40 patients were reviewed (age between 44 and 73 years). OTM treatment lasted on average 17.3±8.5 months. Supportive therapies were scheduled at 2-3-4 months intervals. All patients were compliant with SPC recommended. APT resulted in statistically significant clinical improvement (FMPS and FMBS remained low 20%). Probing depth reduction of 1.5mm, CAL gain of 0.9mm and recession increase of 0.6mm were achieved. Overall, the alveolar bone level slightly increased, but the average root length decreased. A total of 130 teeth were lost during the study period (baseline number 901), representing a mean general loss of 2.8±1.8 teeth per patient. Most affected were multirooted teeth (64.3%) compared to single-rooted teeth (35.7%)
Light smokers 12.5%
Class I or mild Class II malocclusion with migrated and extruded anterior teeth
Increased overjet up to 10mm
Increased overbite up to 9mm
Spacing, extrusion and crowding of mandibular incisors
Lip catching or soft tissue impingement.
Conclusion: The study found that orthodontic movement therapy may be performed safely in patients previously treated for stage IV periodontitis. Nevertheless, the treatment plan must be individualized to meet the patient needs. OTM have no major effects on reduced but healthy periodontium of patients enrolled in a strict SPC.
Topic: Mental foramen/ Flap surgery
Title: Periosteum Classification and Flap Advancement Techniques Around the Mental Foramen
Source: Int J Periodontics Restorative Dent. 2022 Nov-Dec;42(6):753-759.
Keywords: bone regeneration, humans, mental foramen, periosteum, surgery, surgical flaps.
Purpose: to present the flap advancement classification based on periosteum and soft tissue quality
Discussion:Previous surgical interventions will influence the quality and elasticity of the soft tissue at the surgical site. It’s important to assess clinically the area that will receive the procedure in order to stablish a proper surgical plan and anticipated outcome.
The buccal advancement flap in the posterior mandible is a critical step performed to achieve tension free primary closure. Different aspects are important to consider, such as anatomy, incision design, the periosteal scoring incision, and its depth.
|Anatomy||Inferior alveolar nerve. Mental nerve emerges facially from the mental foramen.
Branches innervate the skin of the chin, skin and mucosa of the lower lip, and vestibular gingiva in the MF area.
|Incision Design||Full thickness crestal incision (from retromolar pad to most distal tooth)
Oblique vertical releasing incision (distal and buccal within the retromolar pad)
Distance from grafted site: two teeth anterior
Its recommended a 3-4mm realizing incision at the mesiolingual line angle of the most distal tooth
|Periosteal Scoring incision (PSI)||First identify the MF location (via CBCT)
Using a wet gauze, expose the roof of the MF (correlated to the amount of vertical height of the alveolar ridge). In a ridge with minor vertical deficiency the distance of MF could be up to 15mm from the coronal margin.
Curved PSI around MF (dome-shaped incision)
|Depth of periosteal scoring||As shallow as 0.5mm (Periosteum histologic thickness 0.38mm).
Microscopically the periosteum has two layers. An outer dense fibrous layer that provides mechanical stability; and an inner layer with progenitor cells + fibers anchored to the bone.
Periosteum classification and proposed flap management
Class I. Periosteum with no scar tissue (no history of pathologies). This flap can be performed in two steps. PSI should me made apical to the mucogingival line and perpendicular to the periosteum (1mm deep, extended in one continuous motion). Then, a blunt dissection is used to separate elastic fibers (periosteo-elastic technique). Finally, the scalpel is rotated 45 to 90 degrees to cut the subperiosteal bundles in order to facilitate flap mobility. A second PSI can be made parallel but that usually is not required.
Class II. Mildly fibrotic Periosteum (fibrous tissue has occurred within the soft tissue). When this happens the thickness of periosteum needs to be undermined to reestablish the elasticity of the flap. PSI will be through the fibrotic tissue and a more extensive debundling is done using the blade in 45 degrees. Once finished, the periosteo-elastic technique is performed.
An alternative approach can be made by multiple periosteal scoring incisions + periosteo-elastic technique.
Class III. Difficult flap management due to the presence of thick, fibrotic periosteum (pronounced scarring and foreign substances embedded). Need multiple PSI that penetrate the elastic fibers and muscles and requires a partial or complete removal of the scarred tissue (maintaining a minimum of 1mm thickness). A minimum distance of 3mm from mental foramen is needed. After dissecting the subperiosteal bundles, the fibers are separated with semi-blunt instruments by a repeated pulling motion until the flexibility is reestablished.
Conclusion: Overall the flap advancement classification based on periosteum and soft tissue quality, provides surgical approaches for tissue management to achieve passive, tension-free flap advancement.
Topic: Harvesting autogenous soft tissue
Title: Wound healing dynamics, morbidity, and complications of palatal soft-tissue harvesting.
Source: Periodontol 2000. 2022; 00: 1- 30.
Keywords: biologic agents, morbidity, pain, photobiomodulation, tissue grafts, treatment errors
Purpose: To: 1) evaluate wound healing following palatal harvesting, 2) review clinical errors and complications involved with palatal harvesting, and 3) discuss techniques for minimizing morbidity.
Discussion: Wounds within the oral cavity tend to demonstrate accelerated wound closure and re-epithelialization when compared with skin wounds. Recent histological studies have shown that the transcriptional regulatory network within the basal layer of unwounded, activated oral keratinocytes with reduced differentiation was the major mechanism responsible for promoting accelerated wound repair within oral wounds. When comparing wound healing between a SCTG harvest that heals via primary intention to an FGG harvest healing by secondary intention there are some key differences. Sites healing via primary intention demonstrate re-epithelization within a few hours after injury, thereby sealing the injury within 24-48 hrs, resulting in formation of a new multilayer of oral mucosa by day 5. In contrast, wounds healing by secondary intention require more time due to the larger tissue deficit and more necrotic debris and fibrin that must be removed before epithelialization can take place—which is completed in about 3-5 weeks. The main systemic factors that have been found to delay palatal soft-tissue healing include: increased age, nutritional deficiencies (proteins, carbohydrates, vitamin A, C, E, Mg, copper, Zn, and iron), obesity, alcohol use, smoking, diabetes, and stress. Various biologic agents have been proposed to accelerate palatal wound healing, including topical erythropoietin, hyaluronic acid, and platelet-rich fibrin. There is conflicting evidence between RCTs when comparing palatal healing with the adjunctive use of PRF to no tx at the donor site, with one RCT reporting improved post-op symptoms and another study reporting no difference in morbidity. After reviewing various RCTs that evaluated the use of adjunct biologic modifiers at donor sites it was found that none of the tx protocols obtained complete re-epithelialization after 1 wk, but all sites (regardless of protocol or nontreatment) demonstrated complete re-epithelialization by 4 wks—with ozone therapy, cyanoacrylate tissue glue, and photobiomodulation generating more complete epithelization than spontaneous healing within the first month. In regard to the timing for re-harvesting soft tissue from the same donor site, a minimum of 9 weeks has been recommended to allow for tissue maturation, however studies have shown it may take up to 6 months for palatal connective tissue to regain its presurgical tissue volume and regenerative capabilities. Aside from direct injury to the GPA, increased post-op bleeding can be associated with harvesting technique. The trap door incision technique has been associated with 4x more “leakage” compared to the FGG technique due to injury of larger vessels deeper within the connective tissue. Additionally, more bleeding/leakage is commonly seen in palates with a thin mucosa or shallow vault. Improved hemostasis has been seen with the use of cyanoacrylate, with a mean bleeding time of 1.65min associated with cyanoacrylate alone compared to a bleeding time of 3.18 min when using wet gauze compression, and the combination of PRF + cyanoacrylate resulting in a 0.57min bleeding time.
Conclusion: Significant evidence exists to support the use of hemostatic agents and wound-healing enhancers for managing post-op morbidity following palatal soft-tissue harvesting procedures. Cyanoacrylate tissue adhesive- alone or with a hemostatic collagen sponge—platelet concentrates, hyaluronic acid, photobiomodulation, and ozone therapy can diminish post-op morbidity. The findings from this study support the use of FGG harvesting from the palate or tuberosity (as opposed to the conventional SCTG harvest approach) in several clinical scenarios.
Topic: Ingestion of a foreign object
Title: Accidental ingestion of a dental object during periodontal surgical procedure on IV sedated patient: case management.
Source: Clin Adv Periodontics. 2022; 00: 00- 00.
Type: Case report
Keywords: foreign bodies/diagnostic imaging, radiography, respiratory aspiration/etiology, dental offices, emergencies, deglutition
Purpose: To report a case in which a dental bur was accidentally ingested and to describe how this incident was successfully managed.
Case report: 72 y/o female received EXT/immediate implant placement under IV sedation with Midazolam. During the procedure, the bur detached from the handpiece and dropped into the patient’s oropharynx. The patient immediately coughed and then was instructed to forcibly cough several more times in attempt to expel the bur. After thoroughly examining the oral cavity the bur was not found, so the procedure was stopped immediately, 0.15mg of Flumazenil was administered to reverse the sedation and the pt was immediately escorted to the ER for a chest and abdominal xray. The imaging revealed the presence of the bur within the pt’s abdominal cavity and medical professionals recommended to monitor the pt for several days to see if the bur would be expelled. It was found that after 9 days the bur had still not been expelled, which may have been attributed to the patient’s uniquely elongated colon. Therefore a colonoscopy was performed and the carbide bur was successfully retrieved without incident with no signs or symptoms during the 3-month f/u period.
Background: Foreign objects lost within patient’s oropharynx are ingested 92.5% of the time, and while most of these incidents (90%) pass through the GI tract without complications, 10-20% of these objects require endoscopic removal, and 1% require surgical removal. Ingestion of a dental material should be considered a life-threatening emergency indicating immediate referral to a specialist due to the risk of GI perforation (<1%). The most common site for esophageal impaction is the cricopharyngeal muscle and the most common site of perforation is the ileocecal valve. Random inhalation of dental objects is also considered a medical emergency, with 7.7% of foreign body inhalations being dental-related. Symptoms may not present until days after the incident and may include: breathlessness, wheezing, coughing, fever, right-sided chest pain, and hypoxia. If left untreated, the foreign body inhalation may result in: esophageal erosion, non-resolving pneumonia, atelectasis (collapsed lung), unilateral lung hyperinflation, localized bronchiectasis, and other serious conditions. Aspirations in adults tend to end up in the right lower lobe bronchus due to the larger diameter and less severe branching.
Conclusion: This case illustrates the importance of proper management of dental foreign body aspirations/ingestions, particularly in IV sedated patients. Clinicians should minimize the risks of these complications by using floss ligatures, throat packs, rubber dams, and confirming burs and tools are properly connected to the handpieces and drivers prior to use on patient. In the event of accidental ingestion/inhalation of a foreign object, this should be considered a medical emergency and the patient should receive immediate medical evaluation.
Topic: Biologic Width
Title: Evaluation of biologic width re-establishment using CHU aesthetic gauges in crown lengthening cases- a clinical study
Source: Journal of Oral Biology and Craniofacial Research 13 (2023) 138-145.
Type: Clinical Study
Keywords: Crown lengthening, esthetics, osteotomy, periodontal prosthesis
Background: The Chu Aesthetic Gauge is a plastic color coded tool that helps practitioners perform crown lengthening in a step by step procedure based on tooth width-to-length ratios.
Purpose: To assess the biologic width relocation by performing aesthetic crown lengthening with the help of Chu aesthetic gauges.
Methods: 192 teeth from 17 patients were included. Crown lengthening was performed on 64 maxillary anterior teeth. 128 teeth sharing a proximal surface with the surgical site were used as controls. PI, GI, FGM, CAL, bone sounding, biologic width, and PD were measured at baseline plus three and six months post-op using a custom grooved acrylic stent.
Results: PI and GI showed a significant difference at all intervals, as did FGM and CAL at baseline to three and six months. However, FGM, CAL, bone sounding, biologic width, and PD all showed a non-significant difference at 3 to 6 months.
Conclusion: Using the Chu Aesthetic gauge may help better remove soft and hard tissues and predict final biologic width. This may allow for final prosthesis delivery at just three months post-operative. More studies are needed with larger populations.
Topic: Gingival Unit Transfer
Title: Comparison of the effectiveness of Gingival unit transfer and free Gingival graft in the management of localized Gingival recession – A systematic review
Source: Journal of Oral Biology and Craniofacial Research 13 (2023) 130-137
Keywords: Autograft, gingival unit transfer, FGG, gingival recession
Background: Allen introduced a newer modification of the free gingival graft in 2004, where a palatal graft is taken including marginal gingiva and interdental tissue: Gingival Unit Graft/Transfer.
Purpose: to study and compare the use of Gingival Unit Graft/Transfer (GUG/GUT) (palatal graft including the marginal gingiva and papillae) and FGG in the management of GR.
Methods: Various online databases and journals were searched for RCTs and NRCTS covering the treatment of Miller class I, II, and III defects by GUG. Primary outcome variables included complete and mean root coverage, and vertical recession depth. Secondary outcomes included keratinized tissue width gain, CAL, and PD. All studies had to have at least 6 months follow-up.
Results: Three RCTs were included, all of which studied mandibular incisors, canines, and premolars with vertical recession ≥ 2 mm. Though both techniques had SS improvements in outcomes, GUG showed a greater percentage complete root coverage and vertical recession depth reduction versus traditional FGG. The three RCTs reported 50%, 11%, and 13% CRC for GUG but none for FGG. GUG also had SS greater KT width gain than FGG in all three studies.
Conclusion: More research is needed to fully compare GUG with FGG, but it does appear to be a predictable technique in achieving root coverage. Patient satisfaction and aesthetics also need to be evaluated.
Topic: Platelet-Rich Fibrin
Title: The Effects of Injectable Platelet-Rich Fibrin on Implant Stability
Source: int J Oral Maxillofac Implants. 2022 Nov-Dec;37(6):1145-1150.
Type: Clinical Study
Keywords: Primary implant stability, Injectable platelet-rich fibrin, resonance frequency analysis
Background: injectable platelet–rich fibrin is a liquid platelet concentration with no anticoagulant within the plastic tubes. I-PRF has a significantly higher concentration of platelets, leukocytes, monocytes and granulocytes and prolongs the release of growth factors (ie. TFF-β, PDGF, VEGG) that modulate the immune system, stimulate angiogenesis, increase stem cell adhesion and epithelial mitogenesis. Studies found that I-PRF is more effective compared to PRP in stimulating human osteoblast migration, proliferation and differentiation.
Purpose: The purpose of this study is to determine if injectable platelet-rich fibrin (I-PRF) influences early implant stability
Material and methods: In this study, 15 patients with mandibular edentulous areas were planned for 40 BEGO Sernados RS/RSX implants to be surgically placed at the Zonguldak Bulent Excevit University Oral and Maxilllofacial Surgical clinic. Patients were randomly assigned to 2 groups. In the control group, implants were placed following the BEGO implant system protocol. In the study group, after the osteotomy was prepared, a sterile syringed was used to apply I-PRF into the socket and on the implant surface. Resonance frequency analysis was used to measure implant stability and the implant stability quotient (ISQ) was recorded immediately after the implant was placed, at the 1st, 2nd and 4th week. Statical analysis of all data was completed.
Results: All 40 implants were successfully placed in the patients. The study found that there was no statistically significant difference in the average ISQ values between the study and control group during the time of operation, at 1 week, 2 week and 4 weeks. However, the mean ISQ value statistically decreased between the operation time and 1st week in the control group. In the study group, there was a statistically significant increase in the mean ISQ value between the operation and 2nd week and 4th week.
Conclusions: In conclusion, I-PRF is beneficial for early implant stability and had a positive effect on the implant stability quotient values. This study found that I-PRF can promote bone healing around implants
Topic: Implants and Radiotherapy
Title: Survival of Dental Implants Placed Pre-Radiotherapy Versus Post-Radiotherapy in Native Bone: A Systematic Review
Source: Int J Oral Maxillofac Implants. 2022 Nov-Dec;37(6):1100-1109
Type: Systematic Review
Keywords: Head and neck cancer, radiotherapy, dental implant, survival rate,
Background: Ionizing radiation as a treatment for head and neck cancer can cause irreversible hypervascularity, hypoxia and hypocellularity of the bone, endothelium, periosteum and connective tissue, negatively affecting bone turnover and healing ultimately altering the osseointegration of dental implants.
Purpose: The purpose is to quantify the survival rate of implants placed pre-radiotherapy and post-radiotherapy compared to no radiotherapy in patients with head and neck cancer.
Material and methods: Observational studies, randomized controlled trials, case series and quasi-experimental studies related to the survival rate of dental implants in patients with a history of head and neck cancer receiving radiotherapy were manually and electronically searched from 10 databases. The risk of bias was assessed using the Joanna Briggs Institute critical appraisal tool.
Results: Sixteen studies were included in this study, 4 of which had a high risk of bias, 7 with a moderate risk of bias and 5 studies which had a low risk of bias. Results revealed that there was a median 60-month follow-up period. There is an 80-100% dental implant survival rate when placed post-radiotherapy, 89.4-97% survival rate when placed pre-radiotherapy and 92.2-100% survival rate when placed without radiotherapy. One study showed a statistically higher survival rate for implants placed without radiotherapy compared to implants placed post-radiotherapy. The other 15 studies showed that there was no significant difference between pre-radiotherapy, post-radiotherapy and no radiotherapy. However, all studies showed that there is a higher survival rate of implants in patients who did not receive radiotherapy.
Conclusions: In conclusion, dental implants surgically placed pre-radiotherapy and post-radiotherapy have high survival rates despite the effects of ionizing radiation on peri-implant tissue. Although the survival rates of implants placed in patients receiving radiotherapy are lower in patients that never received radiotherapy, it was not found to be statistically significant and can be considered a relatively safe procedure to help improve the quality of life of these patients. More research with heterogeneity in the survival rates, less bias and better study designs is required.
Topic: Transcrestal sinus elevation
Title: Implant failure and associated risk factors of transcrestal sinus floor elevation: A retrospective study
Source: Clin Oral Implants Res. 2023 Jan;34(1):66-77
Keywords: Implant failure, risk factors, survival rates, transcrestal sinus floor elevation
Purpose: To retrospectively study survival rates of implants placed in transcrestal sinus floor elevation (TSFE) sites to identify potential risk factors
Material and methods: The study included patients who underwent TSFE with simultaneous implant placement in the posterior maxilla. Patients were healthy, had no surgical complications, and had primary stability >15 Ncm. TSFE was completed through greenstick fractures via sequential osteotomes and sinus floor elevation with a mallet. Sites were grafted with Bio-Oss and left submerged for 3+ months.
Results: A total of 803 patients with 976 implants were included. The average follow-up was 48.2 months. The 3-year cumulative survival rate was 96.9%. There were 36 implants lost in 36 patients. Twelve of these failed before or at abutment connection (61 days to 7 months); 2 failed due to early infection, 7 had mobility at uncovery, and 3 were lost at the final impression appointment. The other 24 had late implant failure; 16 failed due to peri-implantitis and 8 due to mechanical complications. The only variables significantly associated with early implant loss were “bone grafting” and “lack of experience of the operator.” Those significantly associated with late implant loss were: residual bone height (RBH) 6mm or less, male gender, and certain implant brands (Nobel and Straumann had significantly higher survival rates than other brands). The interaction between bone grafting and RBH showed a significant synergistic effect.
Conclusions: TSFE with simultaneous implant placement is predictable. Grafting materials and less experienced clinicians may increase the risk of the early implant failures, while low RBH, male patients, and certain brands may increase the risk of late implant failures. Authors recommend allowing implants placed with grafting and TSFE to heal for at least 5 months before uncovering.
Topic: Abutment height
Title: Influence of the abutment height on marginal bone level changes around two-piece dental implants: Meta-analysis and trial sequential analysis of randomized clinical trials.
Source: Clin Oral Implants Res. 2022 Dec 8
Keywords: dental implants, height abutment, marginal bone loss
Purpose: To compare the effect of abutment height (<2mm vs. 2+mm) on marginal bone level
Material and methods: The following PICOS question, “In systemically healthy individuals with at least one implant, what is the efficacy of long (2+mm) compared to short (<2mm) shoulder height abutments in peri-implant marginal bone level (MBL) changes reported by randomized controlled clinical trials?” All implants supported a screw-retained restoration. Only randomized controlled trials with a minimum of 6 months follow-up and 10 patients were included.
Results: A total of 6 studies met the inclusion criteria, three studies included smokers. Results differentiated MBL as <1 and 1+ year. At <1 year, interproximal MBL changes ranged 0.06-0.84mm in the 2+mm group and 0.12-0.83mm in the <2mm group. Abutments 2+mm had significantly lower MBL changes (213 patients). At 1+year, interproximal MBL ranged 003-0.36mm in the 2+mm group and 0.06-0.95mm in the <2mm group. Again, abutments 2+mm had significantly lower MBL changes (253 patients). Additionally, subcrestal implant placement minimized MBL changes to -0.16mm, favoring 2+mm abutments. The authors note that initial mean vertical soft tissue width was not reported in these studies.
Conclusions: Authors cautiously conclude that two-piece implants with 2+mm abutments may have a protective role against changes in MBL at <1 and 1+year. A subcrestal implant position may reduce the abutment height’s effect on MBL changes.
Topic: Lateral Bone Augmentation
Title: Individual “alveolar phenotype” limits dimensions of lateral bone augmentation
Source J Clin Periodontol. 2022 Dec 27. Epub ahead of print. PMID: 36574768.
Type: Retrospective study
Keywords: GBR; alveolar bone; alveolar crest dimensions; bone augmentation; bone resorption; graft resorption; guided bone regeneration; lateral bone augmentation; vertical bone augmentation.
Purpose: To examine the volume stability post lateral augmentation by using three- dimensional reconstruction and superimposed CBCT information compared to the contralateral non-augmented ridge dimensions.
Background: Patients looking to acquire dental implants often have alveolar ridge dimension lacking adequacy due to trauma. To achieve correct 3-D positioning of dental implants, various techniques have been suggested for alveolar ridge reconstruction: guided bone regeneration (GBR), block grafting, shell technique, distraction osteogenesis, transplantation of autologous bone, alveolar ridge splitting, and the use of narrow diameter implants. Implants placed in lateral bone augmentation sites seem to have similar clinical outcomes to implants placed in well preserved bone. Factors that appear to affect the predictability of lateral GBR are defect morphology, biologic principles, technique, and biomaterial placed. There is currently a lack of information regarding the impact of individual phenotypic dimensions or individual natural alveolar crest contour and its limiting of anatomical boundaries for alveolar bone augmentation.
Materials and methods: Patients who previously underwent GBR participated. The patients had to have had a pre-operative cone-beam CT, a CBCT taken immediately following GBR, one or more CBCT scans taken greater than or equal to 6 months after surgery, intact contralateral alveolar bone dimension and a relatively symmetrical maxillary arch. Mimics software was used and the SBCT scans from various points in time were imported. The contra lateral side of augmentation was super imposed onto the site of augmentation. Post standardization, pre-processing and segmentation of all CBCTs, the different jaw segments from the various points in time were imported into Mimics software as STL files, and were color coded based on timepoint to facilitate measurements. Multiplanar reconstructions performed. Linear measurements performed on medical display, and linear measurements performed on axial slices. Eres (mirrored registered site) and Lres (bony envelope following late resorption) were measured over time with relation to IPD (individual phenotypical dimension of the alveolar crest) which was in 2D per mm apically from the alveolar crest in the center of the GBR and in 3D which was the GBR as a whole, 2mm away from the mesial, distal and apical border for standardization. 17 patients participated with 23 lateral bone augmentation sites. 3 different data sets were available. Group A were patients with CBCT pre-GBR, post- GBR, and after 6-8 months of healing to evaluate the mirrored registered site. Group B: patients with a CBCT pre-GBR, post GBR, and a CBCT from >/= 1 year follow up post implant loading in order to estimate the total impact of the mirrored registered site + the bony envelope following late resorption. And Group C were patients with a CBCT pre-GBR, post GBR, 6-8 months post GBR and a CBCT from >/= 1.5 year post GBR.
Results: Group A had an initial horizontal bone gain average of 5.0mm, the grafts reached an average of 2.0mm past the individual phenotypical dimensions of the alveolar crest. After 6-8months it shrank (Eres) to an average of 3.7mm with 0.7mm being outside the IPD. Group B had an initial horizontal bone gain average of 4.7mm, the grafts reached an average of 2.1mm past the individual phenotypical dimensions of the alveolar crest and then after 18months it shrank (Eres+ Lres) to an average of 2.4mm with 0.2mm being inside the IPD. Group C had an initial horizontal bone gain average of 4.8mm, the grafts reached an average of 2.1mm outside the individual phenotypical dimensions of the alveolar crest. After 6-8 months it shrank (Eres) to an average of 3.8mm with 1.0mm being outside the IPD. more than 1 year later (Eres+Lres) it reduced to 2.5mm with the graft outline now being .3mm inside the IPD
Conclusion: The study shows that individual phenotypic dimensions of a person’s bony envelope could potentially be a predictor of how much regeneration of bone can be achieved buccally when using the GBR technique.
Topic: Zygomatic Implants
Title: Retrospective cohort assessment of survival and complications of zygomatic implants in atrophic maxillae
Source: Clin Oral Implants Res. 2022 Dec 21. Epub ahead of print. PMID: 36541107.
Type: Retrospective Cohort Study
Keywords: complication; dental implants; maxillary atrophy; survival; zygoma; zygomatic implants.
Purpose: To explore the survival rate of implants placed in the zygoma and secondly to determine the prevalence of complications, the point in time at which complications occur and the risk factors correlated with implant loss.
Background: An atrophic edentulous maxilla creates a big challenge for rehabilitation. Restoring the arch with conventional implants haslimitations. To avoid grafting technics, zygomatic implants are often considered as a rehabilitation option, which leads to more predictable outcomes and increased acceptance by patients. Literature has documented higher success rates with zygomatic implants versus grafting procedures. Placement of zygomatic implants is prone to certain risks due to the proximity of delicate anatomical structure it is surrounded by. Furthermore, it is a complicated surgery with a steep learning curve.
Materials and methods: This study was a retrospective cohort study. Patients who received zygomatic implants from 1998-2020 were included. Data taken from the file of the patient: age, gender, presence of systemic disease, treatment scheme, number and characteristics of the zygomatic implant, surgical technique, grafting material, type of surgical guide, presence and time point of complications, follow up time, type of prosthesis, and if necessary- the date of implant removal. 302 adults participated, 940 zygomatic implants- 781 rough, 159 machined, 454 immediate loading, 486 delayed loading- and 451 standard implants- 195 rough, 256 machined, 58 immediate loading, 393 delayed loading- were placed. Complications were grouped by: infectious/noninfectious biological and mechanical. Statistical analysis then took place.
Results: 84 standard implants in 38 patients failed and 95 zygomatic implants in 65 patients failed, all of which required removal and caused 28 prostheses to be lost. The average time between placement and removal of the implants was 4.5 years for the zygomatic implants and 4.4 years for the standard implants. 64% of the failed zygomatic implants failed during the first 5 years post placement: 12 were lost in the first 6 months, 9 in the first 7-12 months, 13 during the second year, 14 during the third year, 8 during the fourth year, 5 during the fifth year, 19 between 6-10 years, 11 between 10-15 years and 4 between 15-20 years. 23% of Zygomatic implants with a machine surface were lost. 7% of TiUnite implants were lost. Prosthetic delayed loading had a 15% implant loss rate and immediate loading had a 5% implant loss rate.
The most reported biological infectious complication was sinusitis and occurred at an average of 4.5 year follow up time. The second most common complication was soft tissue infection and it occurred at a 3.2 year average follow up time. Other complications were peri-zygomatic infection, oroantral communications, permanent intraoral dehiscence, peri-implantitis of standard implant, permanent oroantral communication, orbital region infection and fracture of the zygomatic bone. Noninfectious biological complications consisted of transient hypesthesia of the infraorbital nerve, prosthesis dissatisfaction, permanent infraorbital hypoesthesia, intraorbital hematoma and temporomandibular joint dysfunction. Mechanical complications included prosthetic screw loosening, suprastructure fracture, zygomatic bone perforation, prosthetic tooth fracture, zygomatic implant fracture, multiunit abutment fractures and superstructure misfit. Risk factors that predispose zygomatic implants to implant loss: presence of head and neck radiation, hemimaxillectomy, a mixed treatment scheme when compared to a quad scheme, an intrasinusal in comparison to a sinus slot technique, delayed implant loading, the absence of grafting material and the use of static guiding when placing the zygomatic implants. Complications associated with significant occurrence before the implant was lost: zygomatic region infection, sinusitis, perizygomatic infection, permanent oroantral communication and misfit of suprastructure.
Conclusion: Zygomatic implants provide a survival rate of 89.9% for rehabilitation of the maxilla that is severely atrophied. Most implant loss occurred within the first five years of implant placement. The most common complication was sinusitis.
Authors: Avila-Ortiz G, Ambruster J, Barootchi S, Chambrone L, Chen CY, Dixon DR, Geisinger ML, Giannobile WV, Goss K, Gunsolley JC, Heard RH, Kim DM, Mandelaris GA, Monje A, Nevins ML, Palaiologou-Gallis A, Rosen PS, Scheyer ET, Suarez-Lopez Del Amo F, Tavelli L, Velasquez D, Wang HL, Mealey BL
Title: American Academy of Periodontology Best evidence consensus statement on the use of biologics in clinical practice
Source: J Periodontol. 2022 Dec;93(12):1763-1770
Type: consensus statement
Keywords: alveolar ridge preservation, biologics, implant site development, periodontal plastic surgery, periodontal regeneration, periodontal therapy
Purpose: The purpose of this paper is to give a best evidence consensus on biologics which are agents with biological activity used to enhance regenerative or reparative effects. It included autologous blood derived products (ABPs), enamel matrix derivative (EMD), recombinant human platelet-derived growth factor BB (rhPDGF-BB), and recombinant human bone morphogenetic protein 2 (rhBMP-2).
Material and methods: An expert panel was convened to address three focused clinical questions. Systematic reviews were done for each question. The three questions were:
- What is the effect of using biologics on the outcomes of root coverage and gingival augmentation therapy?
- What is the effect of using biologics on the outcomes of surgical therapy of infrabony defects?
- What is the effect of using biologics on outcomes of alveolar ridge preservation or reconstruction (ARP/ARR) and tooth extraction and implant site development (ISD)?”
Results: The first focused question addressed the use of biologics in root coverage gingival augmentation therapy. Current evidence shows biologics used with CAFs for root coverage had statistically and clinically significant improvements. The use of PRF or EMD with CAF resulted in less root coverage compared to subepithelial connective tissue graft with CAF. This should still be considered the gold standard in root coverage. Experts concluded that biologics enhance initial healing and there are no therapeutic downsides to their use. The use of soft tissue graft substitutes and biologics combined may be consider when an autogenous graft is not selected.
The second focused question addressed the use of biologics in surgical therapy of infrabony defects. Current evidence shows that biologics enhance the clinical and radiographic outcomes with rhRDGF-BB and PRF biologics and allogenic and xenogenic bone grafts having superior results. If graft containment is feasible, then a membrane should be avoided as it may prevent some of the benefits of the biologic. The best combination therapy is xenogeneic bone grafts with rhPDGF-BB or PRF. Experts concluded that biologics are safe and effective in use of infrabony defects and can be used with conventional or minimally invasive flap approaches.
The third focused question addressed the use of biologics in ARP/ARR and ISD. There is little current evidence on the use of biologics in these procedures but the use of them had favorable histomorphometric outcomes with mineralized tissue formation observed. Experts concluded that biologics in these cases are safe, but the use of rhBMP-2 has been associated with localized swelling. Biologics may enhance osteogenesis when used with biocompatible/biodegradable scaffolds and the benefits will increase with and increase in defect complexity.
Conclusions: Evidence shows that biologics are safe for use, but the benefits and risks vary based on the biologic’s properties and patient factors. There is evidence showing it is effective in specific indications such as root coverage therapy and infrabony defects, but evidence is limited in other indications such as gingival augmentation therapy, ARP/ARR, and ISD. Expert opinion concludes that biologics do provide added benefits such as reduced surgical time and those benefits are increased with complexity of the defect. Meticulous planning should still be done with consideration of all aspects of the case.
Topic: partial extraction therapy
Title: Clinical outcomes of retention of the buccal root section combined with immediate implant placement: a systematic review of longitudinal studies
Source: Clin Implant Dent Relat Res. 2022 Nov 4
Type: systematic review
Keywords: alveolar ridge resorption, immediate implant placement, partial extraction therapy, PDL-mediated implant placement, periodontal ligament, root-membrane, socket-shield
Purpose: The purpose of this study was to do a systematic review of longitudinal studies evaluating the marginal bone level changes of immediate implant placement with strategic buccal root retention. The socket-shield technique was introduced in 2010 as a method for biological ridge preservation via retention of the PDL. The PDL is linked to resorption and retention of the buccal root portion can eliminate post-extraction resorption. Other techniques included in this review were the root membrane technique and the modified socket-shield technique.
Material and methods: A database search was done for articles published from September 2010 to January 2021. The PICO question being addressed was “In adults undergoing implant treatment (P), does immediate implant placement in conjunction with strategic buccal root retention (I), as compared to conventional immediate implant placement with total extraction (C) lead to improved clinical and radiographic outcomes (O) in clinical trials or cohort studies (S).” Studies included at least 10 participants per group and a minimum of 1 year follow-up.
Results: This review included 10 articles: seven cohort studies and three clinical trials. The success and survival rates of implants of both procedures were comparable. A meta-analysis showed there was less bone dimensional changes in groups with strategic root retention. Across studies, marginal peri-implant bone loss and buccal plate changes were reduced with PDL-mediated implant placement.
Conclusions: Retention of the buccal root section and PDL in select single-rooted teeth can provide dimensional ridge stability and reduce marginal peri-implant bone loss compared to conventional techniques.
Title: Treatment of periodontitis and C-reactive protein: A systematic review and meta-analysis of randomized clinical trials
Source: Journal of Clinical Periodontology, 50( 1), 45– 60
Type: Systematic review and meta-analysis
Keywords: periodontitis, non-surgical periodontal therapy, biomarkers, C-reactive protein
Purpose: To provide an updated assessment of all evidence regarding effects of periodontal treatment on systemic inflammation
Material and methods: Electronic database search to answer, “what is the effect of treatment of periodontitis on circulating CRP levels compared to no treatment after at least 6 months?” Following the PICO format: P, subjects >18 years old; I, non-surgical periodontal therapy (NSPT), NSPT with or without adjunctive therapy; C, no treatment versus supragingival or community dental care; O, primary: circulating CRP levels after 6 months, secondary: changes in other inflammatory biomarkers.
Results: Twenty-six studies were included in this review, including 2941 patients ages 24 to 68. Studies revealed that treatment of periodontitis can reduce levels of several inflammatory biomarkers (WBC, fibrinogen, ICAM-3, ADMA, TNF-α, E-selectin, IL-6, IL-8, and IL-10). All studies reported a decrease in percent BOP.
Majority of the studies found that treatment of periodontitis, in systemically healthy patients, had significant reduction in CRP levels after 6 months. However, no significant reduction in patients with cardiovascular disease. NSPT had statistically significant reduction in CRP levels after 6 months compared to delayed treatment. There was significant reduction in CRP, regardless of severity of periodontitis. Those with higher baseline values of CRP showed greater reduction after treatment. Antibiotics in adjunct to NSPT significantly reduced CRP levels.
Conclusion: There is evidence that suggest non-surgical periodontal treatment can reduce systemic inflammation when evaluating serum CRP levels.
Topic: Risk factors
Title: Risk factors for tooth loss and progression of periodontitis in patients undergoing periodontal maintenance therapy
Source: J Clin Periodontol. 2023;50(1):61-70.
Type: Retrospective study
Keywords: risk factors, tooth loss, disease progression, periodontitis
Purpose: to assess patient- and tooth-level factors to predict tooth loss and periodontitis progression in patients that completed at least 5 years of periodontal maintenance
Material and methods: Retrospective study evaluating patients that had completed both active periodontal therapy (APT) and periodontal maintenance for at least 5 years were examined. Maintenance included oral hygiene instructions, scaling and polishing, and re-instrumentation of residual pockets. Recall intervals were individually assessed for each patient by the clinician. Data was collected from the patients at baseline, after completion of APT, and recall at least 5 years after initial maintenance.
Results: This study included data from 135 subjects, ages 29-75. Majority of patients were diagnosed as Stage III or IV periodontitis. Most patients underwent non-surgical periodontal therapy, 6 patients were prescribed systemic antibiotics, 22 patients had flap surgery, and 17 patients, guided tissue regeneration. Frequency of recall visits ranged from every 3.30 to 16.74 months, with length of maintenance period of 5.09 to 8.65 years.
During the observation period, 7.81% of all teeth were lost, 3.61% of them were loss due to periodontitis. Of the Stage IV periodontitis patients, 76.92% of patients lost at least one tooth due to periodontitis during maintenance and 34.04% for Stage III. Parameters for patient-level risk factors on tooth loss included stage, smoking, diabetes status, sites with PD ≥5 mm, and frequency of maintenance. The tooth level factors associated with tooth loss included PD ≥7 mm at end of APT, Grade 1 and 2 furcation involvement, Grade 1, 2, and 3 mobility, and maximum CAL ≥6 mm.
In regard to periodontitis progression, patient-level risk factors include gender, bleeding scores, compliance, maintenance frequency, and sites with PD ≥5 mm; with significant factors being male gender and maintenance frequency of 5-6 months. The tooth level factors residual PD 5-6 mm at end of APT, Grade 1, 2, and 3 furcation involvement, and maximum CAL of 6 mm. Above 3 mm, each 1 mm increase in PD and CAL was highly associated with increased risk of tooth loss and disease progression.
Conclusion: Stage IV periodontitis, presence of PD ≥5 mm after therapy, residual PD ≥7 mm at end of APT are risk factors for tooth loss. Teeth with PD ≥5 mm at the end of APT are at risk of periodontal disease progression or tooth loss.