Letter to the Editor: Re: The Clinical Effect of Scaling and Root Planing and the Concomitant Administration of Systemic Amoxicillin and Metronidazole: A Systematic Review; Re: Effectiveness of Systemic Amoxicillin/Metronidazole as Adjunctive Therapy to Scaling and Root Planing in the Treatment of Chronic Periodontitis: A Systematic Review and Meta‐Analysis; Re: Effectiveness of Systemic Amoxicillin/Metronidazole as an Adjunctive Therapy to Full‐Mouth Scaling and Root Planing in the Treatment of Aggressive Periodontitis: A Systematic Review and Meta‐Analysis